Tag Archives: lab

Oregon Cannabis Lab Accreditation Program Gets Help, Problems Addressed

By Aaron G. Biros
No Comments

Last week, news of problems facing Oregon’s cannabis laboratory accreditation program surfaced, leading some to speculate about possible delays for the recreational cannabis market. According to The Register-Guard, ORELAP administrator Gary Ward believed the program was “on the precipice of collapse.”

oha_logo_lrgAccording to Jonathan Modie, spokesman for the Oregon Health Authority (OHA), the Oregon Environmental Laboratory Accreditation Program (ORELAP) was anticipating over 30 cannabis laboratories applying for accreditation and they doubled their staff from two to four to prepare for the uptick in applications.

In June, the agency had zero labs applying for accreditation but within two months, 37 labs applied. However, the Oregon Department of Environmental Quality (DEQ) just provided three additional staff members on Monday to help with the application process, says Modie.

Some believe the issues could mean the state may not have enough accredited labs by October 1st, when the recreational cannabis market is expected to go into full swing. “It is difficult to say exactly how many labs we can accredit by October 1,” says Modie. “We have seven labs today which would bring it to nine labs waiting for assessment, but our goal is to get as many labs assessed and hopefully accredited as soon as possible.”

With the additional staff members, Modie is hopeful this will jumpstart the program. “We really appreciate our collaboration with the DEQ and look forward to boosting our capacity a bit to help us get through this busy time,” says Modie.

Part of the reason some laboratories might have trouble meeting prerequisites is simply because the requirements are very strict. “The process involves submitting a quality manual, standard operating procedures, method validation, submitting proficiency testing data and finally undergoing an ORELAP assessment by our staff, so it is a very rigorous process,” says Modie. “This speaks to our concern for making sure they have the right systems in place so public health is protected.” Modie said there were at least three labs that did not pass the assessment.

Roger Voelker
Roger Voelker, lab director at OG Analytical

Bethany Sherman, chief executive officer of OG Analytical, believes the hardest part of the process involves getting accredited for testing pesticides. OG Analytical, based in Eugene, Oregon, has already received their accreditation, one of the first to do so. “The pesticide testing requires our most expensive instrumentation and the sample preparation for testing pesticides is the most time consuming,” says Sherman. “Not only does it require very specific instrumentation, it also requires a real know-how and expertise to ensure we are cleaning samples appropriately, minimizing background noise and looking at the pesticides in trace quantities.” According to Sherman, laboratories are also left to their own devices to develop methodologies specifically for the cannabis matrix, adding to the difficulties.

Rodger Voelker, Ph.D., lab director at OG Analytical, seems confident that the state will be able to handle it. “It is a relief they were able to get some resources from the DEQ and I think the state will not allow a program with this kind of importance to fall apart,” says Voelker. He believes after this initial phase of putting the program in place, the workload will go down. “It is easier to maintain a program than it is to implement,“ adds Voelker. In his eyes, it is crucial for the program to require rigorous science. “People are forced to reconcile that there is a tremendous amount of controls to be considered to produce legally defensible data and I think it is great that the requirements are so strict.”

The OHA’s job is to essentially safeguard public health and they do not want to leave any stone unturned when it comes to potential contamination, says Modie. “This is not just about getting as many labs accredited as possible, this is about protecting public health.”

amandarigdon
The Nerd Perspective

‘Instant’ Cannabis Potency Testing: Different Approaches from Different Manufacturers

By Amanda Rigdon
5 Comments
amandarigdon

This is the first piece of a regular column that CIJ has been so kind to allow me to write for their publication. Some readers might recognize my name from The Practical Chemist column in this publication. Since the inception of that column, I’ve finally taken the plunge into the cannabis industry as chief technical officer of Emerald Scientific. Unlike The Practical Chemist, I will not spend the entire first article introducing the column. The concept is simple: while I find the textbook-esque content of The Practical Chemist scintillating, I have a feeling that the content is a little too heavy to spring on someone who is looking for engaging articles over their precious coffee break. Instead, The Nerd Perspective will consist of less-technical writing focusing on my experience and insights for the cannabis industry as a whole. But don’t worry – I’m sure I will not be able to refrain from technical jargon altogether.

To kick off the column, I want to talk about instrumentation for ‘instant’ cannabis potency testing. At this point, it’s common knowledge in the cannabis analytics industry that the most accurate way to test cannabis potency is through extraction then analysis by HPLC-UV. I agree wholeheartedly with that sentiment, but HPLC analyses have one drawback: they can be either inexpensive or fast – not both. There are some instruments entering the market now that– while not as directly quantitative as HPLC-UV – promise to solve the inexpensive/fast conundrum. During my most recent trip to California, I was able to spend some quality time with two well-known instrument manufacturers: SRI Instruments and PerkinElmer, both of whom manufacture instruments that perform fast, inexpensive cannabis potency analyses. From my previous home at the heights of The Ivory Tower of Chromatography: Home of the Application Chemists, SRI and PE couldn’t be more different. But as seen through the eyes of a company who deals with a wide range of customers and analytical needs, it turns out that SRI and PE are much the same – not only in their open and honest support of the cannabis industry, but also in terms of their love of all things technical.

My first stop was SRI Instruments. They are a relatively small company located in an unassuming building in Torrance, CA. Only a few people work in that location, and I spent my time with Hugh Goldsmith (chief executive officer) and Greg Benedict (tech service guru). I have worked with these guys for a few years now, and since the beginning, I have lovingly referred to them as the MacGyvers of chromatography. Anyone familiar with SRI GCs knows that what they lack in aesthetics, they make up for in practicality – these instruments truly reflect Hugh and Greg’s character (that’s meant as a compliment).

SRI specializes in relatively inexpensive portable and semi-portable instruments that are easy to set up, easy to operate, and most importantly – engineered for a purpose. It’s actually really hard to manufacture an instrument that meets all three of these criteria, and the folks at SRI accomplish this with their passionate and unique approach to problem solving. What I love about these guys is that for them, nothing is impossible. Here’s an example: the price of the portable GC-FID instruments SRI builds is inflated because the instruments require separate – and pricey – hydrogen generators. That’s a big problem – hydrogen generators are all pretty much the same, and none of them are cheap. This didn’t faze SRI: they just decided to design their own super small on-board hydrogen generator capable of supplying hydrogen to a simple GC macgyversystem for six hours with just 20mL of distilled water from the grocery store! I’m not kidding – I saw it in action on their new Model 420 GC (more on that in some future pieces). Was the final product pretty? Not in the least. Did it work? Absolutely. This kind of MacGyver-esque problem solving can only be done successfully with a deep understanding of the core principles behind the problem. What’s more, in order to engineer instruments like these, SRI has to have mastery over the core principles of not only chromatographic separation, but also of software development, electrical engineering, and mechanical engineering – just to name a few. These quirky, unassuming guys are smart. SRI is a company that’s been unapologetically true to themselves for decades; they’ll never be a contender for beauty queen, but they get the job done.

On the surface, PerkinElmer (PE) contrasts with SRI in almost every way possible. With revenue measured in billions of dollars and employees numbering in the thousands, PE is a behemoth that plays not only in the analytical chemistry industry but also in clinical diagnostics and other large industries. Where SRI instruments have a characteristic look of familiar homeliness, PE instruments are sleek and sexy. However, PerkinElmer and SRI are more alike than it would seem; just like the no-frills SRI, the hyper-technical PE instruments are engineered for a purpose by teams of very smart, passionate people.

DoogieWith its modest price tag and manual sample introduction, the SRI Model 420 is engineered for lower throughput users to be a fast, simple, and inexpensive approach to semi-quantitative process control. The purpose of the instruments manufactured by PE is to produce the highest-quality quantitative results as quickly as possible for high-throughput labs. PE instruments are built using the best technology available in order to eke out every last ounce of quantitative accuracy and throughput possible. Fancy technology is rarely inexpensive, and neither is rigorous product development that can last years in some cases. In a way, PE is Doogie Howser to SRI’s MacGyver. Like MacGyver, Doogie is super smart, and his setting is a sterile hospital rather than a warzone.

I had a wonderful conversation with Tim Ruppel, PE’s headspace-GC specialist, on the sample introduction technology incorporated into the TurboMatrix Headspace Sampler, where I also learned that the basic technology for all PerkinElmer headspace-GC instruments was designed by the men who wrote The Book on headspace gas chromatography: Bruno Kolb and Leslie Ettre**. Later, I was able to get a much-needed lesson on FT-IR and the Spectrum Two IR Spectrometer from Brian Smith, PE’s spectroscopy expert, who actually wrote the book on quantitative spectroscopy***. Tim and Brian’s excitement over their technology mirrored that of Hugh and Greg. It turns out that SRI and PerkinElmer are more alike than I thought.

These two instrument manufacturers have addressed the fast/inexpensive conundrum of cannabis potency testing in two different ways: SRI’s instrument is extremely inexpensive, easy to operate, and will provide semi-quantitative values for THC, CBD, and CBN in just a few minutes; PE’s instrument is more expensive up front, but provides quantitative (though not directly quantitative) values for all of the major cannabinoids almost instantly, and requires almost no maintenance or consumables. These two instruments were designed for specific uses: one for inexpensive, easy use, and the other for more comprehensive results with a higher initial investment. The question consumers have to ask themselves is “Who do I need to solve my problem?” For some, the answer will be MacGyver, and for others, Doogie Howser will provide the solution – after all, both are heroes.


** B. Kolb, L. Ettre, Static Headspace-Gas Chromatography: Theory and Practice, John Wiley & Sons, Hoboken, NJ, 2006.

*** Brian C. Smith, Quantitative Spectroscopy: Theory and Practice, Elsevier, Boston, MA, 2002.

teganheadshot
Quality From Canada

The Devil is in the Detail – Changes to Canada’s Cannabis Regs to Encourage Patient Independence and Business Competition

By Tegan Adams, Elfi Daniel-Ivad MSc
No Comments
teganheadshot

Canada’s new ACMPR was launched late last month on August 24th. The key change that most notice is that Canadians may now again grow their own cannabis at home for medical purposes. In addition, more strict guidelines for product testing and labeling requirements for Licensed Producers (LPs) were released.health-canada-logo

Short term pain for long term gain. While the combination of allowing patients to grow at home and more strict regulations for LPs may at first seem like a business disadvantage; overtime LPs will be thankful for the combination switch. Health Canada’s new requirements encourage a leveling of the playing field globally between LPs and large scale product manufacturers of pharmaceuticals, therapeutics and natural health products. The steps Health Canada is taking to regulate our producers, is exactly what they need to get ready for mass production that will be necessary for recreational markets, scheduled for release in Spring 2017.

Picture rows of Tylenol bottles on the shelf at your favorite pharmacy. Now picture rows of cannabis bottles on the shelf beside them. This is what medical cannabis will look like in Canada perhaps as early as 2018, if not sooner. With just under forty LPs on the map and a projected sales volume of modest billions, Canada’s LPs’ eyes are widening with dollar signs as they lube up their oil production and more to see what shelves in Canada will hold.

Curious to know more? Our regulatory department manager Elfi Daniel-Ivad is an expert in regulatory change. She has worked on close to 150 submissions for cannabis licensees in Canada and beyond. Here are a few key changes from her department’s overview to better understand.

MMPR ACMPR (Updated)
No personal production or designated production available to patients (aside from that grandfathered in by MMAR). Personal production and designated production available. Patients may grow 5 indoor plants OR 2 outdoor plants at any given time per gram prescribed to them.
Licensed Producers were not required to label THC or CBD amounts in dried cannabis, though most producers did for sales and educational purposes. Oils had to be labeled with THC and CBD amounts. Licensed Producers must label their percent THC and CBD for dried and fresh cannabis products.
For the labelling of oils, the total quantity of THC, CBD and oil in a container had to be shown. Restrictions on THC allowed no more than 10mg/mL THC per capsule and no more than 30mg/mL THC per mL oil to be distributed. In addition, oil labels must now include information on “carrier” oil and allergen information. Containers must be labelled with number of capsules, the net weight and volume of each capsule. .
No reference to validation of analytical testing methods. Analytical testing must be completed using validated testing methods; confirming reliability and consistency in results for   contaminants, disintegration, residues and THC, THC-A, CBD and CBD-A
Accredited labs can only test products as received from Licensed Producers. In addition to Licensed Producers, patients growing their own or having a designated grower growing for them may also test their products at an accredited lab.

In addition to these changes, it is important to note that if an individual or company has an MMPR proposal already submitted they can now revise it to include oil production (previously, it was first dried bud only). If a company submits a new ACMPR proposal, they can include oil production on their application right away. Interested in submitting your own application? Or need help with one in the USA? Our regulatory department would be happy to answer any questions you might have about the process.

The Practical Chemist

Building the Foundation of Medical Cannabis Testing – Understanding the Use of Standards and Reference Materials – Part 1

By Joe Konschnik
No Comments

In previous articles, you may recall that Amanda Rigdon, one our contributing authors, stated that instrument calibration is the foundation of all data quality. In this article, I would like to expand on that salient point. A properly calibrated instrument will, in fact, produce reliable data. It is the foundation we build our data upon. All foundations are comprised of building blocks, and our laboratory is no exception. If we take this analogy further, the keystone to the laboratory foundation, the stone that all data relies upon, is the analytical reference material. Proper calibration means that it is based on a true, accurate value. That is what the reference material provides. In this article, I would like to expand on the use and types of reference materials in analytical testing.

To develop sound analytical data, it is important to understand the significance of reference materials and how they are properly used. The proper selection and use of reference materials ensures the analytical certainty, traceability and comparability necessary to produce scientifically sound data. First, let’s take a moment to define the types of commonly used reference materials. According to the International Vocabulary of Metrology (VIM), a Reference Standard (RS) is something that is reused to measure against, like a balance or a set of weights. A Reference Material (RM) is a generic term. It is described as something that is prepared using a RS that is homogeneous, stable and is consumed during its use for measurement. An example of an RM is the solutions used to construct a calibration curve, often referred to as calibration standards, on your GC or LC. Due to the current state of cannabis testing, reference materials can be hard to find and, even more critical, variable in their accuracy to a known reference standard. Sometimes this is not critical, but when quantifying an unknown, it is paramount.

RMs can be either quantitative or qualitative. Qualitative RMs verify the identity and purity of a compound. Quantitative RMs, on the other hand, provide a known concentration, or mass, telling us not only what is present, and its purity, but also how much. This is typically documented on the certificate that accompanies the reference material, which is provided by the producer or manufacturer. The certificate describes all of the properties of the starting materials and steps taken to prepare the RM. For testing requirements, like potency, pesticides, etc., where quantitation is expected, it is important to use properly certified quantitative RMs.

Now, the pinnacle of reference materials is the Certified Reference Material (CRM). VIM defines a Certified Reference Material (CRM) as an RM accompanied by documentation issued by an authoritative body and provides one or more specified property values, with associated uncertainties and traceability using valid procedures. A CRM is generally recognized as providing the highest level of traceability and accuracy to a measurement – the strongest keystone you can get for your foundation. It is also important to recognize that the existence of a certificate does not make a reference material a CRM. It is the process used in manufacturing that makes it a CRM, and these are typically accreditations earned by specific manufacturers who have invested on this level of detail.

Now that we understand the types of reference materials we can choose, in the next article of this series we will describe what a CRM provider must do to ensure the material and how we can use them to develop reliable data. Without properly formulated and prepared CRMs, instrument calibration and the use of internal standards are less effective at ensuring the quality of your data.


If you have any questions please contact me, Joe Konschnik at (800) 356-1688 ext. 2002 by phone, or email me at joe.konschnik@restek.com.

amandarigdon
The Practical Chemist

Internal Standards– Turning Good Data Into Great Data

By Amanda Rigdon
2 Comments
amandarigdon

Everyone likes to have a safety net, and scientists are no different. This month I will be discussing internal standards and how we can use them not only to improve the quality of our data, but also give us some ‘wiggle room’ when it comes to variation in sample preparation. Internal standards are widely used in every type of chromatographic analysis, so it is not surprising that their use also applies to common cannabis analyses. In my last article, I wrapped up our discussion of calibration and why it is absolutely necessary for generating valid data. If our calibration is not valid, then the label information that the cannabis consumer sees will not be valid either. These consumers are making decisions based on that data, and for the medical cannabis patient, valid data is absolutely critical. Internal standards work with calibration curves to further improve data quality, and luckily it is very easy to use them.

So what are internal standards? In a nutshell, they are non-analyte compounds used to compensate for method variations. An internal standard can be added either at the very beginning of our process to compensate for variations in sample prep and instrument variation, or at the very end to compensate only for instrument variation. Internal standards are also called ‘surrogates’, in some cases, however, for the purposes of this article, I will simply use the term ‘internal standard.’

Now that we know what internal standards are, lets look at how to use them. We use an internal standard by adding it to all samples, blanks, and calibrators at the same known concentration. By doing this, we now have a single reference concentration for all response values produced by our instrument. We can use this reference concentration to normalize variations in sample preparation and instrument response. This becomes very important for cannabis pesticide analyses that involve lots of sample prep and MS detectors. Figure 1 shows a calibration curve plotted as we saw in the last article (blue diamonds), as well as the response for an internal standard added to each calibrator at a level of 200ppm (green circles). Additionally, we have three sample results (red triangles) plotted against the calibration curve with their own internal standard responses (green Xs).

Figure 1: Calibration Curve with Internal Standard Responses and Three Sample Results
Figure 1: Calibration Curve with Internal Standard Responses and Three Sample Results

In this case, our calibration curve is beautiful and passes all of the criteria we discussed in the previous article. Lets assume that the results we calculate for our samples are valid – 41ppm, 303ppm, and 14ppm. Additionally, we can see that the responses for our internal standards make a flat line across the calibration range because they are present at the same concentration in each sample and calibrator. This illustrates what to expect when all of our calibrators and samples were prepared correctly and the instrument performed as expected. But lets assume we’re having one of those days where everything goes wrong, such as:

  • We unknowingly added only half the volume required for cleanup for one of the samples
  • The autosampler on the instrument was having problems and injected the incorrect amount for the other two samples

Figure 2 shows what our data would look like on our bad day.

Figure 2: Calibration Curve with Internal Standard Responses and Three Sample Results after Method Errors
Figure 2: Calibration Curve with Internal Standard Responses and Three Sample Results after Method Errors

We experienced no problems with our calibration curve (which is common when using solvent standard curves), therefore based on what we’ve learned so far, we would simply move on and calculate our sample results. The sample results this time are quite different: 26ppm, 120ppm, and 19ppm. What if these results are for a pesticide with a regulatory cutoff of 200ppm? When measured accurately, the concentration of sample 2 is 303ppm. In this example, we may have unknowingly passed a contaminated product on to consumers.

In the first two examples, we haven’t been using our internal standard – we’ve only been plotting its response. In order to use the internal standard, we need to change our calibration method. Instead of plotting the response of our analyte of interest versus its concentration, we plot our response ratio (analyte response/internal standard response) versus our concentration ratio (analyte concentration/internal standard concentration). Table 1 shows the analyte and internal standard response values for our calibrators and samples from Figure 2.

 

Table 1: Values for Calibration Curve and Samples Using Internal Standard
Table 1: Values for Calibration Curve and Samples Using Internal Standard

The values highlighted in green are what we will use to build our calibration curve, and the values in blue are what we will use to calculate our sample concentration. Figure 3 shows what the resulting calibration curve and sample points will look like using an internal standard.

Figure 3: Calibration Curve and Sample Results Calculated Using Internal Standard Correction
Figure 3: Calibration Curve and Sample Results Calculated Using Internal Standard Correction

We can see that our axes have changed for our calibration curve, so the results that we calculate from the curve will be in terms of concentration ratio. We calculate these results the same way we did in the previous article, but instead of concentrations, we end up with concentration ratios. To calculate the sample concentration, simply multiply by the internal standard amount (200ppm). Figure 4 shows an example calculation for our lowest concentration sample.

Figure 4: Example Calculation for Sample Results for Internal-Standard Corrected Curve
Figure 4: Example Calculation for Sample Results for Internal-Standard Corrected Curve

Using the calculation shown in Figure 4, our sample results come out to be 41ppm, 302ppm, and 14ppm, which are accurate based on the example in Figure 1. Our internal standards have corrected the variation in our method because they are subjected to that same variation.

As always, there’s a lot more I can talk about on this topic, but I hope this was a good introduction to the use of internal standards. I’ve listed couple of resources below with some good information on the use of internal standards. If you have any questions on this topic, please feel free to contact me at amanda.rigdon@restek.com.


Resources:

When to use an internal standard: http://www.chromatographyonline.com/when-should-internal-standard-be-used-0

Choosing an internal standard: http://blog.restek.com/?p=17050

A2LA, Americans for Safe Access Announce Cannabis-Specific Lab Accreditation

By Aaron G. Biros
2 Comments

The American Association for Laboratory Accreditation (A2LA) and Americans for Safe Access (ASA) announced yesterday a collaboration to develop a cannabis-specific laboratory accreditation program based upon the requirements of ISO/IEC 17025 and ASA’ s Patient Focused Certification (PFC) Program. AccreditationPFC logo for PR under this program will offer the highest level of recognition and provide the most value to the laboratory and users of the products tested, according to a press release published yesterday. ASA is the largest medical cannabis patient advocacy group in the United States. “A2LA is pleased to partner with ASA to offer a cannabis testing laboratory accreditation program to ISO/IEC 17025 as well as the additional laboratory requirements from ASA’s Patient Focused Certification Program,” says Roger Brauninger, biosafety program manager at A2LA.

PFC-A2LA
Pictured left to right: Kristin Nevedal, Program Manager, PFC at ASA;
Jahan Marcu, Ph.D Chief Scientist, PFC at ASA;
Roger Brauninger, BioSafety Program Manager, A2LA;
Michelle Bradac, Senior Accreditation Officer, A2LA

The program affirms that cannabis laboratories are compliant with state and local regulations and ensures that they adhere to the same standards that are followed by laboratories used and inspected by the Environmental Protection Agency (EPA), the United States Department of Agriculture (USDA), and the U.S. Consumer Product Safety Commission (CPSC) among other regulatory bodies. The two non-profit organizations will offer their first joint training course at A2LA’s headquarters in Maryland from July 11th to the 15th. During this course, participants will receive training on PFC’s national standards for the cultivation, manufacture, dispensing, and testing of cannabis and cannabis products, combined with ISO/IEC 17025 training.

The guidelines for cannabis operations that serve as the basis for this accreditation program were issued by the American Herbal Products Association (AHPA) Cannabis Committee, an industry stakeholder panel, and have already been adopted by sixteen states. “We are very excited to see the PFC program join the ISO/IEC 17025 accreditation efforts to help fully establish a robust and reliable cannabis testing foundation,” says Jeffrey Raber, chief executive officer of The Werc Shop, a PFC-certified cannabis testing laboratory. “It is a great testament to ASA’s commitment to quality in their PFC program by partnering with a world-renowned accrediting body to set a new standard for cannabis testing labs.”A2LA logo

According to Kristin Nevedal, program director of PFC, this is an important first in the industry. “This new, comprehensive accreditation program affirms laboratory operations are meeting existing standards and best practices, adhering to the ISO/IEC 17025 criteria, and are compliant with state and local regulations,” says Nevedal. “This program is the first of its kind developed specifically for the cannabis industry, giving confidence to patients as well as regulators that their test results on these products are accurate and consistent.”

“The program will combine the expertise and resources of the country’s largest accreditation body with the scientific rigor and knowledge base of the nation’s largest medical cannabis advocacy group, benefitting the myriad of laboratories tasked with analyzing cannabis products,” says Nevedal. According to Brauninger, a cannabis-specific accreditation program is vital to the industry’s constantly shifting needs. “The ability to now offer a cannabis testing laboratory accreditation program that is tailored to address the unique concerns and issues of the industry will help to add the necessary confidence and trust in the reliability and safety of the cannabis products on the market,” says Brauninger. “Those laboratories that gain accreditation under this program will be demonstrating that they adhere to the most comprehensive and relevant set of criteria by their compliance to both the underlying framework of the internationally recognized ISO/IEC 17025:2005 quality management system standard and the specific guidelines issued by the AHPA Cannabis Committee.” This type of collaboration could represent a milestone in progress toward achieving a higher level of consumer safety in the cannabis industry.

amandarigdon
The Practical Chemist

Calibration Part II – Evaluating Your Curves

By Amanda Rigdon
No Comments
amandarigdon

Despite the title, this article is not about weight loss – it is about generating valid analytical data for quantitative analyses. In the last installment of The Practical Chemist, I introduced instrument calibration and covered a few ways we can calibrate our instruments. Just because we have run several standards across a range of concentrations and plotted a curve using the resulting data, it does not mean our curve accurately represents our instrument’s response across that concentration range. In order to be able to claim that our calibration curve accurately represents our instrument response, we have to take a look at a couple of quality indicators for our curve data:

  1. correlation coefficient (r) or coefficient of determination (r2)
  2. back-calculated accuracy (reported as % error)

The r or r2 values that accompany our calibration curve are measurements of how closely our curve matches the data we have generated. The closer the values are to 1.00, the more accurately our curve represents our detector response. Generally, r values ≥0.995 and r2 values ≥ 0.990 are considered ‘good’. Figure 1 shows a few representative curves, their associated data, and r2 values (concentration and response units are arbitrary).

Figure 1: Representative Curves and r2 values
Figure 1: Representative Curves and r2 values

Let’s take a closer look at these curves:

Curve A: This represents a case where the curve perfectly matches the instrument data, meaning our calculated unknown values will be accurate across the entire calibration range.

Curve B: The r2 value is good and visually the curve matches most of the data points pretty well. However, if we look at our two highest calibration points, we can see that they do not match the trend for the rest of the data; the response values should be closer to 1250 and 2500. The fact that they are much lower than they should be could indicate that we are starting to overload our detector at higher calibration levels; we are putting more mass of analyte into the detector than it can reliably detect. This is a common problem when dealing with concentrated samples, so it can occur especially for potency analyses.

Curve C: We can see that although our r2 value is still okay, we are not detecting analytes as we should at the low end of our curve. In fact, at our lowest calibration level, the instrument is not detecting anything at all (0 response at the lowest point). This is a common problem with residual solvent and pesticide analyses where detection levels for some compounds like benzene are very low.

Curve D: It is a perfect example of our curve not representing our instrument response at all. A curve like this indicates a possible problem with the instrument or sample preparation.

So even if our curve looks good, we could be generating inaccurate results for some samples. This brings us to another measure of curve fitness: back-calculated accuracy (expressed as % error). This is an easy way to determine how accurate your results will be without performing a single additional run.

Back-calculated accuracy simply plugs the area values we obtained from our calibrators back into the calibration curve to see how well our curve will calculate these values in relation to the known value. We can do this by reprocessing our calibrators as unknowns or by hand. As an example, let’s back-calculate the concentration of our 500 level calibrator from Curve B. The formula for that curve is: y = 3.543x + 52.805. If we plug 1800 in for y and solve for x, we end up with a calculated concentration of 493. To calculate the error of our calculated value versus the true value, we can use the equation: % Error = [(calculated value – true value)/true value] * 100. This gives us a % error of -1.4%. Acceptable % error values are usually ±15 – 20% depending on analysis type. Let’s see what the % error values are for the curves shown in Figure 1.

practical chemist table 1
Table 1: % Error for Back-Calculated Values for Curves A – D

Our % error values have told us what our r2 values could not. We knew Curve D was unacceptable, but now we can see that Curves B and C will yield inaccurate results for all but the highest levels of analyte – even though the results were skewed at opposite ends of the curves.

There are many more details regarding generating calibration curves and measuring their quality that I did not have room to mention here. Hopefully, these two articles have given you some tools to use in your lab to quickly and easily improve the quality of your data. If you would like to learn more about this topic or have any questions, please don’t hesitate to contact me at amanda.rigdon@restek.com.

derekpeterson

Terra Tech Expands, Maintains Quality: A Q&A with CEO Derek Peterson

By Aaron G. Biros
No Comments
derekpeterson
derekpeterson
Derek Peterson, chief executive officer of Terra Tech

Terra Tech, with the recent acquisition of Blum, a dispensary in Oakland, and the line of concentrates, IVXX, is sweeping the cannabis industry by setting standards for safety and quality. Terra Tech, publicly traded in the Over-The-Counter market, is well known as an agricultural company, with the subsidiary brand, Edible Garden, selling produce to Whole Foods, Wal-Mart and Kroger’s. In December of last year, we covered Terra Tech’s entrance into the cannabis marketplace and their experience with large-scale, sustainable agriculture. We sit down with Derek Peterson, chief executive officer of Terra Tech, to get an update on their progress and quality controls.

CannabisIndustryJournal: In January, Terra Tech announced revenue guidance of $20-22 million for 2016. Can you share some of your strategy going forward to meet your goals?

rsz_img_2343
Terra Tech is taking organic and GFSI-certified agricultural practices to growing cannabis

Derek Peterson: We have always played both a long game as well as a short game, meaning while we are building our longer term business, like in Nevada, we are also focusing on short term accretive acquisitions, like we did with Blum in Oakland. We want to make sure we capture short-term revenue growth while we plan our future revenue production. We feel confident about achieving those results.

CIJ: How big of a role does the acquisition of Blum and IVXX brand expansion play in meeting those goals?

Blumoakland
The Oakland location of Blum dispensary

Derek: Blum is a significant factor even though we are only capturing three quarters of revenue considering we closed the deal on March 31st of this year. So for the full year of 2017 we will have growth from this level considering we will be able to report a full year of Blum revenue. IVXX presents us with the best opportunity for growth in the coming years. As the market in California and Nevada grows we can continue to expand our IVXX footprint throughout the state. Being able to wholesale to thousands of other retail facilities affords us a significant opportunity to grow our sales.

CIJ: How do you think the brand of Edible Garden positions you well for expansion in the cannabis industry? 

Poinsettias ready for distribution at Edible Garden facility in Belvidere, New Jersey
Produce ready for distribution at Edible Garden facility in Belvidere, New Jersey

Derek: One of the reasons we were so successful in the Nevada market was because regulators and legislators felt a high degree of confidence in our abilities considering we are USDA organic, Kosher and GFSI-certified. Our traditional agricultural experience has been very synergistic with our cannabis division from both an optics and operational perspective.

CIJ: Could you give us an update on progress in Medifarm LLC in Nevada? And on your distribution plan for IVXX in California?

IVXXconcentrates
IVXX concentrates

Derek: We are continuing to expand our IVXX line throughout the state and increasing our sales force. In addition we will continue to develop new products to distribute into our existing supply chain, like we just did with our new pre filled cartridge line.

We are opening our Decatur location in Las Vegas in early July and Reno and Desert Inn towards the end of August. Our cultivation and extraction facilities should be complete no later than January 2017. We will have our entire infrastructure in place if the recreational bill passes in Nevada this November.

Blum Las Vegas location will open in July
Blum Las Vegas location will open in July

CIJ: Tell us about the role of laboratory testing in your business.

Derek: Laboratories play a significant role, as they are becoming a mandated step in most new legislation around the company. Independent lab testing is extremely important to maintain safe access for consumers and patients. We work primarily with Steep Hill Labs and CW analytics.

CIJ: Can you expand on your integrated pest management and your growing practices?

stickerscannabis
Platinum Cookies ready for packaging and labelling

Derek: Well we cannot say organic, however we do cultivate all naturally. We also cultivate traditional produce that we sell to major retailers. We are USDA organic-certified and we implement similar processes in our cannabis cultivation. Pest control is extremely challenging for any farmer but we rely primarily on bio control, meaning the good bugs eat the bad bugs. This has been very effective for us in the cultivation of all our products.

CIJ: How is your business different from the slew of other dispensaries and growers in California?

Consistency in quality standards requires meticulous SOPs
Consistency in quality standards requires meticulous SOPs

Derek: Service and consistency; we have over 42,000 registered patients and our operations team has over 19 years of experience in California. One of the reasons we have become one of the largest dispensaries in the state is because of that experience. In addition, consistency is extremely important. Consumers expect the same product in every other business and ours is no different. If they come in for our Platinum Cookies one month and the next month it has different characteristics you are going to lose patient confidence. So in the front of the house, we are focused on pairing patients’ needs with the correct product and in the back of the house we are focused on providing a meticulously cultivated product, produced at the highest standards.

CIJ: Can you delve into some of the processing for concentrates? How do you meet such rigorous quality standards?

IVXX processing
Extraction equipment in one of the processing facilities for IVXX

Derek: Through research and development, we have engineered a proprietary process in which our solvent profiles used under our proprietary conditions ensures solvent residual levels which are not detected by instrumentation at 3rd party testing agencies such as Steep Hill Labs. In addition, any good scientific method requires repetition and corroboration of results. In order to accomplish this we also rely on random routine testing in which we send out extracts out to other 3rd party testing labs. Proprietary conditions include, but are not limited to, heat, vacuum, agitation, etc. By utilizing the correct amalgamation of solvent profiles, extraction conditions, purging conditions, as well as rigorous quality control standards, we are able to ensure a product that is void of any residual solvents, without sacrificing potency or identity of the cannabinoids and terpenes. Cannabinoids and terpenes are of chief interest when extracting cannabis for patients so that they have access to these essential oils without any of the actual leaf and bud.

All solvents used are the highest grade available to us, which ensures a truly medical product for the patient. In addition, all of our extraction equipment is routinely cleaned and sterilized using medical grade cleaning agents.

teganheadshot
Quality From Canada

Secure Software Monitoring — Two Keys to Success

By Tegan Adams
No Comments
teganheadshot

We have two key software platforms at our laboratory that help us stay compliant with our standard operating procedures. Saif Al-Dujaili, quality manager at Eurofins-Experchem, oversees quality assurance in our laboratory. As we like to say, you are safe with Saif.

A Customized Sample Tracking System

Sample-tracking software consists of four main modules:

Tracking samples in our facility: When a sample is booked by our tracking system, a unique identification number is generated by the system and printed on a sticker, which is placed on the sample. When a sample is booked, department heads then have the ability to assign work orders to the analysts through the tracking system.

When testing is complete, results are entered by the analyst into the tracking system and reviewed by the quality assurance (QA) department. QA reviewers are responsible for approving results entered in the system before they are sent to the client. A certificate of analysis is then generated and e-mailed to the client for their review.

Controlling stability studies conducted in our facility: Stability studies are scheduled and controlled on different samples pulled for analysis. Within our facility’s sample-tracking system we have different chamber names with different conditions where products can be placed. Which chamber we place samples in depends on protocols and requests from our client. The software used also generates a unique study number for each stability study that occurs. The stability schedule that includes each study is reviewed every week by the stability coordinator to schedule what samples need to be pulled for testing.

Controlling methods used for tests: Methods are entered into the tracking system after department heads have reviewed them and it is approved by QA. The tracking system generates a unique ID number for each method as well as each sample. The method can now be tracked in our laboratory’s system. Within the software you can enter the name of the method, client name and effective date and any revisions applied to the method.

Controlling inventory of columns and electrodes: Sample tracking also helps us with our purchasing patterns to make sure we have supplies for our client’s testing needs. Every time that columns and electrodes are received, they are entered into our tracking system for inventory purposes.

REES Environmental Monitoring Software

REES is used to monitor the environmental conditions of our testing facility. Key inputs measured include temperature, humidity, differential pressure and elimination or intensity of light. REES is linked to the QA department’s computers. An audible alarm is sounded as well as e-mails sent to QA personnel to notify them if anything is out of specification. REES also phones related personnel’s cell phones to notify them of any alarms. No alarms are missed, even if they occur after working hours. Having a 24-hour environmental monitoring system in place helps Eurofins-Experchem ensure integrity in operations of stability, microbiological and other environmental conditions essential for accuracy in testing results.

amandarigdon
The Practical Chemist

Easy Ways to Generate Scientifically Sound Data

By Amanda Rigdon
1 Comment
amandarigdon

I have been working with the chemical analysis side of the cannabis industry for about six years, and I have seen tremendous scientific growth on the part of cannabis labs over that time. Based on conversations with labs and the presentations and forums held at cannabis analytical conferences, I have seen the cannabis analytical industry move from asking, “how do we do this analysis?” to asking “how do we do this analysis right?” This change of focus represents a milestone in the cannabis industry; it means the industry is growing up. Growing up is not always easy, and that is being reflected now in a new focus on understanding and addressing key issues such as pesticides in cannabis products, and asking important questions about how regulation of cannabis labs will occur.

While sometimes painful, growth is always good. To support this evolution, we are now focusing on the contribution that laboratories make to the safety of the cannabis consumer through the generation of quality data. Much of this focus has been on ensuring scientifically sound data through regulation. But Restek is neither a regulatory nor an accrediting body. Restek is dedicated to helping analytical chemists in all industries and regulatory environments produce scientifically sound data through education, technical support and expert advice regarding instrumentation and supplies. I have the privilege of supporting the cannabis analytical testing industry with this goal in mind, which is why I decided to write a regular column detailing simple ways analytical laboratories can improve the quality of their chromatographic data right now, in ways that are easy to implement and are cost effective.

Anyone with an instrument can perform chromatographic analysis and generate data. Even though results are generated, these results may not be valid. At the cannabis industry’s current state, no burden of proof is placed on the analytical laboratory regarding the validity of its results, and there are few gatekeepers between those results and the consumer who is making decisions based on them. Even though some chromatographic instruments are super fancy and expensive, the fact is that every chromatographic instrument – regardless of whether it costs ten thousand or a million dollars – is designed to spit out a number. It is up to the chemist to ensure that number is valid.

In the first couple of paragraphs of this article, I used terms to describe ‘good’ data like ‘scientifically-sound’ or ‘quality’, but at the end of the day, the definition of ‘good’ data is valid data. If you take the literal meaning, valid data is justifiable, logically correct data. Many of the laboratories I have had the pleasure of working with over the years are genuinely dedicated to the production of valid results, but they also need to minimize costs in order to remain competitive. The good news is that laboratories can generate valid scientific results without breaking the bank.

In each of my future articles, I will focus on one aspect of valid data generation, such as calibration and internal standards, explore it in practical detail and go over how that aspect can be applied to common cannabis analyses. The techniques I will be writing about are applied in many other industries, both regulated and non-regulated, so regardless of where the regulations in your state end up, you can already have a head start on the analytical portion of compliance. That means you have more time to focus on the inevitable paperwork portion of regulatory compliance – lucky you! Stay tuned for my next column on instrument calibration, which is the foundation for producing quality data. I think it will be the start of a really good series and I am looking forward to writing it.