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Multi-analyte Configuration for Cannabis Testing Services

Managing Cannabis Testing Lab Workflows using LIMS

By Dr. Susan Audino
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Multi-analyte Configuration for Cannabis Testing Services

With the state led legalization of both adult recreational and medical cannabis, there is a need for comprehensive and reliable analytical testing to ensure consumer safety and drug potency. Cannabis-testing laboratories receive high volumes of test requests from cannabis cultivators for testing quantitative and qualitative aspects of the plant. The testing market is growing as more states bring in stricter enforcement policies on testing. As the number of testing labs grow, it is anticipated that the laboratories that are now servicing other markets, including high throughput contract labs, will cross into cannabis testing as regulations free up. As the volume of tests each lab performs increases, the need for laboratories to make effective use of time and resource management, such as ensuring accurate and quick results, reports, regulatory compliance, quality assurance and many other aspects of data management becomes vital in staying competitive.

Cannabis Testing Workflows

To be commercially competitive, testing labs offer a comprehensive range of testing services. These services are available for both the medical and recreational cannabis markets, including:

  • Detection and quantification of both acid and neutral forms of cannabinoids
  • Screening for pesticide levels
  • Monitoring water activity to indicate the possibility of microbiological contamination
  • Moisture content measurements
  • Terpene profiling
  • Residual solvents and heavy metal testing
  • Fungi, molds, mycotoxin testing and many more

Although the testing workflows differ for each test, here is a basic overview of the operations carried out in a cannabis-testing lab:

  1. Cannabis samples are received.
  2. The samples are processed using techniques such as grinding and homogenization. This may be followed by extraction, filtration and evaporation.
  3. A few samples will be isolated and concentrated by dissolving in solvents, while others may be derivatized using HPLC or GC reagents
  4. The processed samples are then subjected to chromatographic separation using techniques such as HPLC, UHPLC, GC and GC-MS.
  5. The separated components are then analyzed and identified for qualitative and quantitative analysis based on specialized standards and certified reference materials.
  6. The quantified analytical data will be exported from the instruments and compiled with the corresponding sample data.
  7. The test results are organized and reviewed by the lab personnel.
  8. The finalized test results are reported in a compliant format and released to the client.

In order to ensure that cannabis testing laboratories function reliably, they are obliged to follow and execute certain organizational and regulatory protocols throughout the testing process. These involve critical factors that determine the accuracy of testing services of a laboratory.

Factors Critical to a Cannabis Testing Laboratory 

  • Accreditations & Regulatory Compliance: Cannabis testing laboratories are subject to regulatory compliance requirements, accreditation standards, laboratory practices and policies at the state level. A standard that most cannabis testing labs comply to is ISO 17025, which sets the requirements of quality standards in testing laboratories. Accreditation to this standard represents the determination of competence by an independent third party referred to as the “Accreditation Body”. Accreditation ensures that laboratories are adhering to their methods. These testing facilities have mandatory participation in proficiency tests regularly in order to maintain accreditation.
  • Quality Assurance, Standards & Proficiency Testing: Quality assurance is in part achieved by implementing standard test methods that have been thoroughly validated. When standard methods are not available, the laboratory must validate their own methods. In addition to using valid and appropriate methods, accredited laboratories are also required to participate in appropriate and commercially available Proficiency Test Program or Inter-Laboratory Comparison Study. Both PT and ILC Programs provide laboratories with some measure of their analytic performance and compare that performance with other participating laboratories.

    Multi-analyte Configuration for Cannabis Testing Services
    CloudLIMS Cannabis Testing LIMS: Multi-analyte Configuration for Cannabis Testing Services
  • Real-time Collaboration: Testing facilities generate metadata such as data derived from cannabis samples and infused products. The testing status and test results are best served for compliance and accessibility when integrated and stored on a centralized platform. This helps in timely data sharing and facilitates informed decision making, effective cooperation and relationships between cannabis testing facilities and growers. This platform is imperative for laboratories that have grown to high volume throughput where opportunities for errors exist. By matching test results to samples, this platform ensures consistent sample tracking and traceability. Finally, the platform is designed to provide immediate, real-time reporting to individual state or other regulatory bodies.
  • Personnel Management: Skilled scientific staff in cannabis-testing laboratories are required to oversee testing activities. Staff should have experience in analytical chromatography instruments such as HPLC and GC-MS. Since samples are often used for multi-analytes such as terpenes, cannabinoids, pesticides etc., the process often involves transferring samples and tests from one person to another within the testing facility. A chain of custody (CoC) is required to ensure traceability and ‘ownership’ for each person involved in the workflow.

LIMS for Laboratory Automation

Gathering, organizing and controlling laboratory-testing data can be time-consuming, labor-intensive and challenging for cannabis testing laboratories. Using spreadsheets and paper methods for this purpose is error-prone, makes data retrieval difficult and does not allow laboratories to easily adhere to regulatory guidelines. Manual systems are cumbersome, costly and lack efficiency. One way to meet this challenge is to switch to automated solutions that eliminate many of the mundane tasks that utilize valuable human resources.. Laboratory automation transforms the data management processes and as a result, improves the quality of services and provides faster turnaround time with significant cost savings. Automating the data management protocol will improve the quality of accountability, improve technical efficiency, and improve fiscal resources.

cloudlims screenshot
Real Time Test Status in CloudLIMS

A Laboratory Information Management System (LIMS) is a software tool for testing labs that aids efficient data management. A LIMS organizes, manages and communicates all laboratory test data and related information, such as sample and associated metadata, tests, Standard Operating Procedures (SOPs), test reports, and invoices. It also enables fully automated data exchange between instruments such as HPLCs, GC-FIDs, etc. to one consolidated location, thereby reducing transcription errors.

How LIMS Helps Cannabis Testing Labs

LIMS are much more capable than spreadsheets and paper-based tools for streamlining the analytical and operational lab activities and enhances the productivity and quality by eliminating manual data entry. Cloud-enabled LIMS systems such as CloudLIMS are often low in the total cost of acquisition, do not require IT staff and are scalable to help meet the ever changing business and regulatory compliance needs. Some of the key benefits of LIMS for automating a cannabis-testing laboratory are illustrated below [Table 1]:

Key Functionality Benefit
Barcode label designing and printing Enables proper labelling of samples and inventory

Follows GLP guidelines

Instant data capture by scanning barcodes Facilitates quick client registration and sample access
3600 data traceability Saves time and resources for locating samples and other records
Inventory and order management Supports proactive planning/budgeting and real time accuracy
Custodian management Promotes overall laboratory organization by assigning custodians for samples and tests

Maintains the Chain-of-custody (CoC)

Test management Accommodates pre-loaded test protocols to quickly assign tests for incoming samples
Accounting for sample and inventory quantity Automatically deducts sample and inventory quantities when consumed in tests
Package & shipment management Manages incoming samples and samples that have been subcontracted to other laboratories
Electronic data import Electronically imports test results and metadata from integrated instruments

Eliminates manual typographical errors

Report management Generates accurate, customizable, meaningful and test reports for clients

Allows user to include signatures and additional sections for professional use

21 CFR Part 11 compliant Authenticates laboratory activities with electronic signatures
ISO 17025 accreditation Provides traceable documentary evidence required to achieve ISO 17025 accreditation
Audit trail capabilities Adheres to regulatory standards by recording comprehensive audit logs for laboratory activities along with the date and time stamp
Centralized data management Stores all the data in a single, secure database facilitating quick data retrieval
Workflow management Promotes better data management and resource allocation
High-configurability Enables modification of screens using graphical configuration tools to mirror testing workflows
State compliance systems Integrates with state-required compliance reporting systems and communicates using API
Adheres to regulatory compliance Creates Certificates of Analysis (CoA) to prove regulatory compliance for each batch as well as batch-by-batch variance analysis and other reports as needed.
Data security & confidentiality Masks sensitive data from unauthorized user access

 

Cloud-based LIMS encrypts data at rest and in-transit while transmission between the client and the server

Global accessibility Cloud-based LIMS provides real-time access to laboratory data from anytime anywhere
Real-time collaboration Cloud-based LIMS enhances real-time communication within a laboratory, between a laboratory and its clients, and across a global organization with multiple sites

Table 1. Key functionality and benefits of LIMS for cannabis testing laboratories

Upon mapping the present day challenges faced by cannabis testing laboratories, adopting laboratory automation solutions becomes imperative. Cloud-based LIMS becomes a valuable tool for laboratory data management in cannabis testing laboratories. In addition to reducing manual workloads, and efficient resource management, it helps labs focus on productive lab operations while achieving compliance and regulatory goals with ease.

For more information on this, check out a webinar here: Webinar: How to Meet Cannabis Testing Standards and Regulatory Requirements with LIMS by Stephen Goldman, laboratory director at the State of Colorado certified Cannabis testing facility, PhytaTech.

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EVIO Labs: The First Accredited Cannabis Lab in Florida

By Lauren Masko
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EVIO Logo

EVIO Labs recently became the first cannabis laboratory in Florida to obtain ISO 17025 accreditation. Perry Johnson Laboratory Accreditation, Inc. (PJLA), an organization that provides third-party assessments to ISO/IEC 17025, accredited EVIO Labs. The assessment process that lead to ISO 17025 accreditation for EVIO Labs included a thorough review of their quality management system, their capability to perform potency and contaminant testing for cannabis products.

Tracy Szerszen, president and operations manager at PJLA, encourages this international standard for laboratories to provide confidence to end-users that the test results they receive are reliable. She says laboratories that achieve this accreditation are showing they have the proper tools, equipment and staff to provide accurate testing. “It is a very critical component of the industry, and becoming accredited provides the assurance that laboratories are performing to the highest standard,” says Szerszen. “EVIO Labs has taken the right step in their commitment towards meeting this standard and providing clean and safe cannabis for the patients of Florida.”

PJLAEVIO Labs provides cannabis testing for cannabinoid and terpene profiles, microbiological and pesticides contamination, residual solvent, heavy metals, mycotoxins, water activity and moisture content. Chris Martinez, co-founder and president of EVIO Labs Florida explains that the Florida Department of Health mandates that an independent third-party laboratory tests medical cannabis to ensure that these products are safe for human consumption. Martinez says their first priority is the safety of their patients, and ensuring that EVIO Labs provides clean and safe cannabis for Florida.

Chris Martinez
Chris Martinez, co-founder and president of EVIO Labs Florida

Martinez launched their laboratory with some help from Shimadzu last year. “Our Broward lab is powered by Shimadzu with over $1.2M in the latest testing equipment utilizing LCMS technology with the world’s fastest polarity switching time of 5 m/sec and scan speeds of 30,000 u/sec with UF Qarray sensitivity 90 times that of previously available technologies,” says Martinez. According to Martinez, their licensing agreement with EVIO Labs (OTC:SGBYD) marked a first for the publicly traded company with exclusivity in the Florida market. The agreement includes proprietary testing methodologies, operating procedures, training and support.

Every certificate of analysis is reviewed by a lab director with over 20 years of experience operating in FDA regulated labs. Martinez says that EVIO has some of the most advanced technology in the industry, which provides them the opportunity to quickly provide results, frequently as fast as a 24-hour period. Martinez and his team are currently building a 3,300 square-foot laboratory in Gainesville, which is expected to be running by March of this year.

Growing Pains a Month Into California’s Market Launch

By Aaron G. Biros
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For about a month now, California’s adult use market has been open for business and the market is booming. About thirty days into the world’s largest adult use market launch, we are beginning to see side effects of the growing pains that come with adjusting the massive industry.

Consumers are also feeling sticker shock as the new taxes add up to a 40% increase in price.While the regulatory and licensing roll out has been relatively smooth, some municipalities are slower than others in welcoming the adult use cannabis industry. It took Los Angeles weeks longer than other counties to begin licensing dispensaries. Meanwhile, retailers in San Diego say the first month brought a huge influx of customers, challenging their abilities to meet higher-than-expected demand.

Businesses are struggling to deal with large amounts of cash, but California State Treasurer John Chiang may have a solution in store. Yesterday, his department announced they are planning to create a taxpayer-backed bank for cannabis businesses.

Reports of possible supply shortages are irking some businesses, fearing that the state hasn’t licensed enough growers and distributors to handle the high demand. Consumers are also feeling sticker shock as the new taxes add up to a 40% increase in price.

CA cannabis testing chart
California’s plan for phasing in testing requirements.

In the regulatory realm, some are concerned that a loophole in the rules allows bigger cultivation operations to squeeze out the competition from smaller businesses. The California Growers Association filed a lawsuit against the California Department of Food and Agriculture to try and close this loophole, hoping to give smaller cultivators a leg up before bigger companies can dominate the market.

The Bureau of Cannabis Control (known as just “The Bureau”) began holding meetings and workshops to help cannabis businesses get acquainted with the new rules. Public licensing workshops in Irvine and San Diego held last week were designed to focus on information required for licensing and resources for planning. The Bureau also held their first cannabis advisory committee meeting, as well as announcing new subcommittees and an input survey to help the Bureau better meet business needs.

On the lab-testing front, the state has phased in cannabinoids, moisture content, residual solvent, pesticide, microbial impurities and homogeneity testing. On July 1, the state will phase in additional residual solvent and pesticide testing in addition to foreign material testing. At the end of 2018, they plan on requiring terpenoids, mycotoxins, heavy metals and water activity testing as well.

PA Approves First Two Cannabis Labs

By Aaron G. Biros
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According to a PennLive article, Pennsylvania’s Department of Health approved the first two cannabis laboratories for their medical cannabis program. ACT Laboratories of Pennsylvania LLC and Keystone State Testing LLC are the companies that were approved to perform analytical testing for safety and quality in cannabis products.

Both laboratories expect to be operational before the end of 2017, according to the PennLive article. Those labs are required to test for CBD and THC content, pesticides, moisture content, residual solvents and microbiological contaminants.

The temporary lab testing regulations are somewhat comprehensive, detailing lab reporting, licensing, sampling protocols and ownership stipulations, among other rules. ACT and Keystone, the labs that were approved by the Department of Health, have their approval for two years and can renew their license after.

While the state still expects the program to be fully implemented by 2018, Health Secretary and Physician General Dr. Rachel Levine said last week they are hoping to launch the program sometime next year, according to a press release. December 2017 will mark a full year since the state opened applications for licensing businesses.

January 2018 has long been the goal for the full implementation of the program. “We have made significant progress in getting this program off the ground since Governor Wolf signed the Medical Marijuana Act into law last year,” says Dr. Levine. “These proposed regulations for patients and caregivers to participate are one of the final pieces we need to have in place to launch the program sometime next year.”

Chris English
The Practical Chemist

Accurate Detection of Residual Solvents in Cannabis Concentrates

By Chris English
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Chris English

Edibles and vape pens are rapidly becoming a sizable portion of the cannabis industry as various methods of consumption popularize beyond just smoking dried flower. These products are produced using cannabis concentrates, which come in the form of oils, waxes or shatter (figure 1). Once the cannabinoids and terpenes are removed from the plant material using solvents, the solvent is evaporated leaving behind the product. Extraction solvents are difficult to remove in the low percent range so the final product is tested to ensure leftover solvents are at safe levels. While carbon dioxide and butane are most commonly used, consumer concern over other more toxic residual solvents has led to regulation of acceptable limits. For instance, in Colorado the Department of Public Health and Environment (CDPHE) updated the state’s acceptable limits of residual solvents on January 1st, 2017.

Headspace Analysis

Figure 1: Shatter can be melted and dissolved in a high molecular weight solvent for headspace analysis (HS). Photo Courtesy of Cal-Green Solutions.

Since the most suitable solvents are volatile, these compounds are not amenable to HPLC methods and are best suited to gas chromatography (GC) using a thick stationary phase capable of adequate retention and resolution of butanes from other target compounds. Headspace (HS) is the most common analytical technique for efficiently removing the residual solvents from the complex cannabis extract matrix. Concentrates are weighed out into a headspace vial and are dissolved in a high molecular weight solvent such as dimethylformamide (DMF) or 1,3-dimethyl-3-imidazolidinone (DMI). The sealed headspace vial is heated until a stable equilibrium between the gas phase and the liquid phase occurs inside the vial. One milliliter of gas is transferred from the vial to the gas chromatograph for analysis. Another approach is full evaporation technique (FET), which involves a small amount of sample sealed in a headspace vial creating a single-phase gas system. More work is required to validate this technique as a quantitative method.

Gas Chromatographic Detectors

The flame ionization detector (FID) is selective because it only responds to materials that ionize in an air/hydrogen flame, however, this condition covers a broad range of compounds. When an organic compound enters the flame; the large increase in ions produced is measured as a positive signal. Since the response is proportional to the number of carbon atoms introduced into the flame, an FID is considered a quantitative counter of carbon atoms burned. There are a variety of advantages to using this detector such as, ease of use, stability, and the largest linear dynamic range of the commonly available GC detectors. The FID covers a calibration of nearly 5 orders of magnitude. FIDs are inexpensive to purchase and to operate. Maintenance is generally no more complex than changing jets and ensuring proper gas flows to the detector. Because of the stability of this detector internal standards are not required and sensitivity is adequate for meeting the acceptable reporting limits. However, FID is unable to confirm compounds and identification is only based on retention time. Early eluting analytes have a higher probability of interferences from matrix (Figure 2).

Figure 2: Resolution of early eluting compounds by headspace – flame ionization detection (HS-FID). Chromatogram Courtesy of Trace Analytics.

Mass Spectrometry (MS) provides unique spectral information for accurately identifying components eluting from the capillary column. As a compound exits the column it collides with high-energy electrons destabilizing the valence shell electrons of the analyte and it is broken into structurally significant charged fragments. These fragments are separated by their mass-to-charge ratios in the analyzer to produce a spectral pattern unique to the compound. To confirm the identity of the compound the spectral fingerprint is matched to a library of known spectra. Using the spectral patterns the appropriate masses for quantification can be chosen. Compounds with higher molecular weight fragments are easier to detect and identify for instance benzene (m/z 78), toluene (m/z 91) and the xylenes (m/z 106), whereas low mass fragments such as propane (m/z 29), methanol (m/z 31) and butane (m/z 43) are more difficult and may elute with matrix that matches these ions. Several disadvantages of mass spectrometers are the cost of equipment, cost to operate and complexity. In addition, these detectors are less stable and require an internal standard and have a limited dynamic range, which can lead to compound saturation.

Regardless of your method of detection, optimized HS and GC conditions are essential to properly resolve your target analytes and achieve the required detection limits. While MS may differentiate overlapping peaks the chances of interference of low molecular weight fragments necessitates resolution of target analytes chromatographically. FID requires excellent resolution for accurate identification and quantification.

emerald test retail

Analyzing The Emerald Test Results: Cannabis Labs Making Progress

By Aaron G. Biros
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emerald test retail

The Emerald Test advisory panel recently convened to review the results from the Fall 2016 round of the semi-annual Inter-Laboratory Comparison and Proficiency Test (ILC/PT), ahead of the third annual Emerald Conference just a few weeks away. After reviewing and analyzing the results, the panel noticed a significant improvement across the board over their Spring 2016 round of proficiency testing.rsz_emerald-scientific_letterhead-1

Emerald Scientific’s ILC/PT program is a tool laboratories use to check how accurate their testing capabilities are compared to other labs. A lab receiving The Emerald Test badge indicates their testing meets the criteria established by the panel to demonstrate competency. This means that they were within two standard deviations of the consensus mean for all analytes tested, according to Wes Burk, vice president of Emerald Scientific. He says the labs performed better than expected on both the microbial and pesticide tests.

Wes Burk, vice president of Emerald Scientific.
Wes Burk, vice president of Emerald Scientific.

emerald test retailEach lab has access to raw, anonymized data including a consensus mean, z-scores and kernel density plots. This round measured how well 35 cannabis labs perform in testing for potency, pesticides, residual solvents and microbial contaminants such as E. coli, Salmonella, Coliform, yeast and mold.

The advisory panel includes: Robert Martin, Ph.D., founder of CW Analytical, Cynthia Ludwig, director of technical services at AOCS, Rodger Voelker, Ph.D., lab director, OG Analytical, Tammie Mussitsch, QA manager at RJ Lee Group, Shawn Kassner, senior scientist at Neptune & Company, Inc., Jim Roe, scientific director at Steep Hill Labs, Chris Hudalla, Ph.D., founder and chief scientific officer at ProVerde Labs, Sytze Elzinga, The Werc Shop and Amanda Rigdon, Chief Technical Officer at Emerald Scientific.

amandarigdon
Amanda Rigdon, chief technical officer at Emerald Scientific

According to Amanda Rigdon, chief technical officer at Emerald Scientific, the labs performed very well in potency, residual solvents and microbial testing PTs. This is the first year the proficiency testing includes pesticides. “All of the labs did a great job identifying every pesticide in our hemp-based PT, but some more work will most likely have to be done to bring quantitative results in line,” says Rigdon. “Since this was the first pesticide PT we had offered, we were pretty conservative when choosing analytes and their levels. For the most part, analytes and levels were taken from the Oregon pesticide list, which is widely recognized to be the most reasonable and applicable pesticide list out there to date.” They covered pesticides of high concern, like abamectin and Myclobutanil, but also included a wide range of other pesticides that labs are expected to encounter.

Shawn Kassner, senior scientist at Neptune
Shawn Kassner, senior scientist at Neptune & Company, Inc.

Shawn Kassner, senior scientist at Neptune & Company, Inc., believes microbial contamination proficiency testing should be a priority for improving public health and safety going forward. Although five participating labs did not receive badges for the microbial contamination PTs, panel members say the overall performance was really quite good. “Microbiology testing are essential analyses for all cannabis products and it’s just slower in regulatory implementation than potency testing,” says Kassner. “The risk of Salmonella and E. coli to an individual using a medical cannabis product could be very life threatening. Microbiology contamination is a huge concern for any public health agency, which is why we have seen that microbiology testing is usually the first analytical test required after potency.” Kassner notes that there were few outliers and with each Emerald PT program, he is seeing an improvement in overall laboratory performance.

For The Emerald Test’s next round, the panel hopes to make some improvements in the test’s robustness and consistency, like obtaining assigned values for all samples and comparing to a consensus mean. “We want to develop permanent badge criteria, streamline the appeals process and possibly implement a qualitative performance review in the pesticide PT,” says Burk. For the next round of pesticide PTs, they want to build a better list of pesticides to cover more states, allowing labs to pick a set based on their state’s regulations. Burk says they also want to collect data on whether or not matrix-matched curves were used for pesticides.

Rodger Voelker, Cynthia Ludwig and Shawn Kassner, all members of the advisory panel, will be speaking at the Emerald Conference, discussing some of their findings from this round of proficiency testing. The Emerald Conference will take place February 2nd and 3rd in San Diego, CA.

The Practical Chemist

Appropriate Instrumentation for the Chemical Analysis of Cannabis and Derivative Products: Part 1

By Rebecca Stevens
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Election Day 2016 resulted in historic gains for state level cannabis prohibition reform. Voters in California, Maine, Massachusetts and Nevada chose to legalize adult use of Cannabis sp. and its extracts while even traditionally conservative states like Arkansas, Florida, Montana and North Dakota enacted policy allowing for medical use. More than half of the United States now allows for some form of legal cannabis use, highlighting the rapidly growing need for high quality analytical testing.

For the uninitiated, analytical instrumentation can be a confusing mix of abbreviations and hyphenation that provides little obvious information about an instrument’s capability, advantages and disadvantages. In this series of articles, my colleagues and I at Restek will break down and explain in practical terms what instruments are appropriate for a particular analysis and what to consider when choosing an instrumental technique.

Potency Analysis

Potency analysis refers to the quantitation of the major cannabinoids present in Cannabis sp. These compounds are known to provide the physiological effects of cannabis and their levels can vary dramatically based on cultivation practices, product storage conditions and extraction practices.

The primary technique is high performance liquid chromatography (HPLC) coupled to ultraviolet absorbance (UV) detection. Gas chromatography (GC) coupled to a flame ionization detector (FID) or mass spectrometry (MS) can provide potency information but suffers from issues that preclude its use for comprehensive analysis.

Pesticide Residue Analysis

Pesticide residue analysis is, by a wide margin, the most technically challenging testing that we will discuss here. Trace levels of pesticides incurred during cultivation can be transferred to the consumer both on dried plant material and in extracts prepared from the contaminated material. These compounds can be acutely toxic and are generally regulated at part per billion parts-per-billion levels (PPB).

Depending on the desired target pesticides and detection limits, HPLC and/or GC coupled with tandem mass spectrometry (MS/MS) or high resolution accurate mass spectrometry (HRAM) is strongly recommended. Tandem and HRAM mass spectrometry instrumentation is expensive, but in this case it is crucial and will save untold frustration during method development.

Residual Solvents Analysis

When extracts are produced from plant material using organic solvents such as butane, alcohols or supercritical carbon dioxide there is a potential for the solvent and any other contaminants present in it to become trapped in the extract. The goal of residual solvent analysis is to detect and quantify solvents that may remain in the finished extract.

Residual solvent analysis is best accomplished using GC coupled to a headspace sample introduction system (HS-GC) along with FID or MS detection. Solid phase microextraction (SPME) of the sample headspace with direct introduction to the GC is another option.

Terpene Profile Analysis

While terpene profiles are not a safety issue, they provide much of the smell and taste experience of cannabis and are postulated to synergize with the physiologically active components. Breeders of Cannabis sp. are often interested in producing strains with specific terpene profiles through selective breeding techniques.

Both GC and HPLC can be employed successfully for terpenes analysis. Mass spectrometry is suitable for detection as well as GC-FID and HPLC-UV.

Heavy Metals Analysis

Metals such as arsenic, lead, cadmium, chromium and mercury can be present in cannabis plant material due to uptake from the soil, fertilizers or hydroponic media by a growing plant. Rapidly growing plants like Cannabis sp. are particularly efficient at extracting and accumulating metals from their environment.

Several different types of instrumentation can be used for metals analysis, but the dominant technology is inductively coupled plasma mass spectrometry (ICP-MS). Other approaches can also be used including ICP coupled with optical emission spectroscopy (ICP-OES).

Rebecca is an Applications Scientist at Restek Corporation and is eager to field any questions or comments on cannabis analysis, she can be reached by e-mail, rebecca.stevens@restek.com or by phone at 814-353-1300 (ext. 2154)

An inductively coupled plasma torch used in MS reaches local temperatures rivaling the surface of the sun. Image by W. Blanchard, Wikimedia
An inductively coupled plasma torch used in Optical Emission Spectroscopy (OES) reaches local temperatures rivaling the surface of the sun. Image by W. Blanchard, Wikimedia