Tag Archives: high performance liquid chromatography

Shimadzu Launches Cannabis Analyzer for Potency

By Aaron G. Biros
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On Monday, March 6th, Shimadzu Scientific Instruments, a leading laboratory analytical instrumentation manufacturer, announced the launch of a new product focused on cannabis, according to a press release. Their Cannabis Analyzer for Potency is essentially a high-performance liquid chromatograph (HPLC) packaged with integrated hardware, software, workflows and all the supplies. The supplies include an analytical column, guard columns, mobile phase and a CRM standard mixture.canAnalyzerImg1

The instrument is designed to test for 11 cannabinoids in less time and with greater ease than traditional HPLC instruments. In the press release, they claim “operators are now able to produce accurate results with ease, regardless of cannabis testing knowledge or chromatography experience.” One very unique aspect of the instrument is the lack of experience required to run it, according to Bob Clifford, general manager of marketing at Shimadzu. “We have our typical chromatography software [LabSolutions] with an overlay that allows the user to analyze a sample in three simple steps,” says Clifford. Those in the cannabis industry that have a background in plant science, but not analytical chemistry, could run potency analyses on the instrument with minimal training. “This overlay allows ease of use for those not familiar with chromatography software,” says Clifford.

An overlay of a flower sample with the standards supplied in the High-Sensitivity Method package.
An overlay of a flower sample with the standards supplied in the High-Sensitivity Method package.

The instrument can determine cannabinoid percentages per dry weight in flower concentrates and edibles. “Once you open the software, it will get the flow rate started, heat the column up and automatically begin to prep for analysis,” says Clifford. Before the analysis begins, information like the sample ID number, sample name, sample weight, extraction volume and dilution volume are entered. After the analysis is complete all the test results are reported for each sample.

Because laboratories wouldn’t have to develop quantitative testing methodology, they argue this instrument would save a lot of time in the lab. “After one day of installation and testing, users are equipped with everything they need to obtain cannabis potency results,” states the press release. According to Clifford, method development for potency analysis in-house can take some labs up to three months. “We can bring this instrument to the lab and have it ready for testing almost immediately,” says Clifford. “The methods for this instrument were developed by a team of twenty scientists working on different platforms at our Innovation Center and was tested for ruggedness, repeatability and quantitative accuracy.”

Screenshots from the software on the instrument
Screenshots from the software on the instrument

The instrument’s workflow is designed to meet three methods of analysis depending on testing needs. The High Throughput method package can determine quantities of ten cannabinoids with less than eight minutes per sample. The method was developed in collaboration with commercial testing laboratories. The High Sensitivity method package adds THCV to that target analyte list with ten minutes per analysis. The method provides the sharpest chromatographic peaks and best sensitivity. The High Resolution method package offers full baseline resolution for those 11 cannabinoids in less than 30 minutes per analysis and the ability to add cannabinoids to that target list if regulations change.

The press release states the interface should allow users to reduce the number of steps needed in the analysis and simplify the workflow. The instrument comes with a three-year warranty, preventative maintenance plan and lifetime technical support.

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
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Quality From Canada

Near Infrared, GC and HPLC Applications in Cannabis Testing

By Tegan Adams, Michael Bertone
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When a cannabis sample is submitted to a lab for testing there is a four-step process that occurs before it is tested in the instrumentation on site:

  1. It is ground at a low temperature into a fine powder;
  2. A solution is added to the ground powder;
  3. An extraction is repeated 6 times to ensure all cannabinoids are transferred into a common solution to be used in testing instrumentation.
  4. Once the cannabinoid solution is extracted from the plant matter, it is analyzed using High Pressure Liquid Chromatograph (HPLC). HPLC is the key piece of instrumentation in cannabis potency testing procedures.

While there are many ways to test cannabis potency, HPLC is the most widely accepted and recognized testing instrumentation. Other instrument techniques include gas chromatography (GC) and thin layer chromatography (TLC). HPLC is preferred over GC because it does not apply heat in the testing process and cannabinoids can then be measured in their naturally occurring forms. Using a GC, heat is applied as part of the testing process and cannabinoids such as THCA or CBDA can change form, depending on the level of heat applied. CBDA and THCA have been observed to change form at as low as 40-50C. GC uses anywhere between 150-200C for its processes, and if using a GC, a change of compound form can occur. Using HPLC free of any high-heat environments, acidic (CBDA & THCA) and neutral cannabinoids (CBD, THC, CBG, CBN and others) can be differentiated in a sample for quantification purposes.

Near Infrared

Near infrared (NIR) has been used with cannabis for rapid identification of active pharmaceutical ingredients by measuring how much light different substances reflect. Cannabis is typically composed of 5-30% cannabinoids (mainly THC and CBD) and 5-15% water. Cannabinoid content can vary by over 5% (e.g. 13-18%) on a single plant, and even more if grown indoors. Multiple NIR measurements can be cost effective for R&D purposes. NIR does not use solvents and has a speed advantage of at least 50 times over traditional methods.

The main downfall of NIR techniques is that they are generally less accurate than HPLC or GC for potency analyses. NIR can be programmed to detect different compounds. To obtain accuracy in its detection methods, samples must be tested by HPLC on ongoing basis. 100 samples or more will provide enough information to improve an NIR software’s accuracy if it is programmed by the manufacturer or user using chemometrics. Chemometrics sorts through the often complex and broad overlapping NIR absorption.

Bands from the chemical, physical, and structural properties of all species present in a sample that influences the measured spectra. Any variation however of a strain tested or water quantity observed can affect the received results. Consistency is the key to obtaining precision with NIR equipment programming. The downfall of the NIR technique is that it must constantly be compared to HPLC data to ensure accuracy.

At Eurofins Experchem , our company works with bothHPLC and NIR equipment simultaneously for different cannabis testing purposes. Running both equipment simultaneously means we are able to continually monitor the accuracy of our NIR equipment as compared to our HPLC. If a company is using NIR alone however, it can be more difficult to maintain the equipment’s accuracy without on-going monitoring.

What about Terpenes?

Terpenes are the primary aromatic constituents of cannabis resin and essential oils. Terpene compounds vary in type and concentration among different genetic lineages of cannabis and have been shown to modulate and modify the therapeutic and psychoactive effects of cannabinoids. Terpenes can be analyzed using different methods including separation by GC or HPLC and identification by Mass Spectrometry. The high-heat environment for GC analysis can again cause problems in accuracy and interpretation of results for terpenes; high-heat environments can degrade terpenes and make them difficult to find in accurate form. We find HPLC is the best instrument to test for terpenes and can now test for six of the key terpene profiles including a-Pinene, Caryophyllene, Limonene, Myrcene, B-Pinene and Terpineol.

Quality Systems

Quality systems between different labs are never one and the same. Some labs are testing cannabis under good manufacturing practices (GMP), others follow ISO accreditation and some labs have no accreditation at all.

From a quality systems’ perspective some labs have zero or only one quality system employee(s). In a GMP lab, to meet the requirements of Health Canada and the FDA, our operations are staffed in a 1:4 quality assurance to analyst ratio. GMP labs have stringent quality standards that set them apart from other labs testing cannabis. Quality standards we work with include, but are not limited to: monthly internal blind audits, extensive GMP training, yearly exams and ongoing tests demonstrating competencies.

Maintaining and adhering to strict quality standards necessary for a Drug Establishment License for pharmaceutical testing ensures accuracy of results in cannabis testing otherwise difficult to find in the testing marketplace.

Important things to know about testing

  1. HPLC is the most recommended instrument used for product release in a regulated environment.
  2. NIR is the best instrument to use for monitoring growth and curing processes for R&D purposes, only if validated with an HPLC on an ongoing basis.
  3. Quality Systems between labs are different. Regardless of instrumentation used, if quality systems are not in place and maintained, integrity of results may be compromised.
  4. GMPs comprise 25% of our labour costs to our quality department. Quality systems necessary for a GMP environment include internal audits, out of specification investigations, qualification and maintenance of instruments, systems controls and stringent data integrity standards.