Separation of cannabinoids for clinical use

PrepChrom C-700: Isolation of cannabidiol (CBD) and tetrahydrocannabinol (THC) from other cannabinoids extracted from cannabis

PrepChrom WordPressThe separation of cannabinoids is an important process which is necessary for clinical studies. The aim of these studies is to investigate the effect of the isolated cannabinoids on patients suffering from chronic illnesses and side effects caused by chemotherapy. The relaxation of laws concerning medical use of cannabis all around the world, especially the United States, has increased the interest in determining the effect of cannabinoids on the human body. Clinical studies require large amount of highly pure separated cannabnnoids. This can easily be achieved with the PrepChrom C-700.


Cannabis is an extremely versatile plant and has been used for many purposes throughout history. Some specific sorts are used for fibers in the textile and paper industry because of their long stems. It is a useful source of foodstuffs, such as hemp oil and seed. Due to the cannabinoids, cannabis is also a popular recreational drug. These substances can cause mental and physical effects when consumed. The impact of the cannabinoids on the human body is of great interest for the pharmaceutical sector. The research emphasis lies in treating the side effects of chemotherapy, inflammatory diseases like multiple sclerosis or degenerative illnesses such as Parkinson’s disease.[3] AI FAME GmbH, a Swiss company, is a pioneering company to extract the plant-based active substances and make them water-soluble for improved, further processing.

Here, we aim to separate three cannabinoids, i.e. cannabidiol, tetrahydrocannabinol and tetrahydrocannabinolic acid in high purity from the extract.


Equipment: PrepChrom C-700

Sample: Water-soluble cannabis extract. Cultivated, extracted and provided by AI FAME GmbH

Preparation: The chromatographic separation is performed with 1 mL of the water-soluble cannabis extract diluted in 1 mL methanol : water (1:1)

Separation: Method parameters
Column:  Sepacore® C-18 80 g
Particle size:  40-63 μm
Flow rate:  40 mL/min
Sample loop:  2 mL
Detection:  253, 270 nm and SCAN 200-600 nm

Gradient: methanol (A) : water(B)
50 % – 90 % methanol (A) in 20 min
90 % – 90 % methanol (A) in 10 min
90 % – 95 % methanol (A) in 5 min
95 % – 95 % methanol (A) in 10 min


Cannabidiol (CBD) bearing a 1,3-diol functional group on its benzene ring, is the first substance to be eluted when applying reversed phase conditions (Figure 1), hence, is the most polar cannabinoid in the sample. The second compound, eluting after 27 minutes, is tetrahydrocannabinol (THC). The last substance to be eluted is tetrahydrocannabinolic acid (THCA), a form of cannabinoid which easily decarboxilates in to THC when exposed to light or heat. Assignment of the signals and identification was done by comparison with reference HPLC data provided by AI FAME GmbH.

Cannabinoide SN finalFigure 1: Methanol : water separation of the extracted cannabinoids using the PrepChrom C-700. Detection at 270 nm, 254 nm, and 200-600 nm SCAN.




The three cannabinoids extracted by AI FAME GmbH could easily be separated and separately collected with the PrepChrom C-700.

The water-solubility of the extract enables the use of aqueous solvents that have inherent economic and ecologic advantages over common organic solvents.

The growing interest in the clinical use of cannabinoids is unbreakable. Furthermore, cannabis is decriminalized and it is allowed to exploit the potential of its valuable substances. BUCHI offers straight forward solutions to separate and purify small to large size batches of the precious extracts.


AI FAME GmbH, Switzerland, is thanked for providing the extract and for the fruitful analytical discussion.


[1] Sutton, IR. Daeniken, P. (2006). Cannabinoids in the management of intractable chemotherapy-induced nausea and vomiting and cancer-related pain. The Journal of Supportive Oncology.

[2] State Medical Marijuana Laws. National Conference of State Legislatures. (16.3.2015).

[3] Kogan, NM. Mechoulam, R. (2007) Cannabinoids in health and disease. Dialogues Clin Neurosci. 2007 Dec; 9(4): 413–430.

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EPA compliant sample preparation for environmental analysis

Current regulatory developments in the US market have led to increased use of the BUCHI Syncore in contract labs

Environmental_landscape lr

Industrialization, globalization, economic growth and an expanding green conscience demand a qualitative and quantitative leap in environmental protection and analysis. This development is widely supported, globally accepted, and increasingly impacts local as well as global regulation and law. Numerous countries have implemented strict regulations or have tightened their demand for an environmentally sustainable economy during recent years.

One of the latest and most prominent examples for tightened legislation is the United States Environmental Protection Agency (US EPA). The US EPA has not only lowered the threshold values for numerous harmful emissions for both industry and research, but has also started to tightly regulate laboratories responsible for testing such emissions. This has created quite a significant environmental testing industry, mostly consisting of customer contract laboratories specialized in testing various environmental samples in accordance to US EPA regulations. Recent news from several US states indicate that the agency has started to enforce those regulations and closely monitor affected institutions. This has already led to several substantial and publicly released monetary fines in 2014. The main point of interest of the US EPA is the organic solvent balance of affected companies. Solvents purchased and used by companies must be accounted for upon disposal, discrepancies are attributed to loss of solvent to the atmosphere. Among other factors, organic solvent emissions are a critical influence on air pollution and the greenhouse effect. Companies which fail to verify their solvent turnover are subject to further EPA investigations.

This situation becomes important once contract labs have reached a certain size. With dozens or hundreds of mandatory solvent exchanges and evaporations every day, the solvent emission factor becomes a serious aspect for every company in this segment.

For more than 75 years the family owned Swiss company, BÜCHI Labortechnik AG, has been known as a leading provider for solutions in rotary and parallel evaporation. Sustainability is one of BUCHI’s core values, a creed that has resulted in many environmentally friendly innovations and products which aim to conserve energy and water resulting in the smallest possible impact on the environment. One such product is the Syncore® Analyst, a highly productive parallel evaporator combined with the latest SVR (solvent vapor recovery system) technology, which allows simultaneous drying or concentration of up to 12 samples to a pre-defined residual volume at low temperatures while applying gentle vacuum conditions.

The Syncore® is tailored to the demands of modern high-throughput environmental laboratories. High analyte recoveries, even of sensitive compounds such as SVOCs, are obtained by means of a chilled zone at the bottom of each sample vessel. When used in combination with the programmable BUCHI vacuum controller and the individual sample sealing work quality is increased by automating processes to produce reproducible results and eliminate the chance of samples going to dryness or being cross-contaminated. High analyte recoveries are further obtained using a chilled Flushback module. The Flushback module partially condenses the solvent vapor at the top part of the sample vessel generating a continuous rinsing along the glass wall. Thus, adsorption of analytes at the glass wall is avoided.

The solvent vapor is condensed at the primary condenser and collected, a post-pump secondary condenser makes sure no solvent vapors escape the evaporation system. As a result, solvent recoveries greater than 95% are achieved. This not only eliminates harmful solvent emissions inside the laboratory, it is also beneficial to the environment and saves money as the recovered solvent can be reused.

Automated parallel sample concentration with high analyte and solvent recovery is achieved with the Syncore® Analyst. The Syncore® technology reduces manual labor and is fully compliant with the latest amendments to the regulations by the US EPA Solvent Emission Program, yielding solvent recoveries greater than 95%.

Current regulatory developments in the US market have therefore led to increased use of the BUCHI Syncore in these contract labs. This increased popularity of the Syncore not only proves that the combination of fast parallel evaporation, low cost per sample, and high solvent recovery is unrivaled, but also that the instrument is fully compliant with the latest emission regulations.

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Voice of the customer:
“If you’re looking to take your laboratory to a better level of quality, efficiency, and environmental friendliness, the Syncore Analyst is the way to go”
>> Download Case Study

Lionel Thomas, Laboratory Manager,
Accutest Laboratories, NJ

Solutions for alcoholic beverages

From raw material to the drinks you taste

Different alcoholic drinksIn this modern, digital world consumer product experiences are rapidly communicated to a global audience. More than ever before, the value of a brand is reflected in the quality and consistency of every single product introduced into the marketplace despite the possible variation in the raw material quality or the production process. The production of alcoholic beverages with consistent taste and quality requires experience and quality control at all stages of production, from raw material inspection to final product analysis.

BUCHI understands how to assist the manufacturers of alcoholic beverages in meeting your goals and offers solutions for the entire production cycle.

Production cycle step Sample matrix Analyte Analysis technology
Raw material e.g. barley, hops, grapes Moisture, protein, nitrogen, alpha and beta bitter acid, storage index NIRSolutions
Malting, fermentation,
wine pressing,
Malt, grains Total nitrogen, soluble nitrogen, moisture, acid, alcohol, starch NIRSolutions
Final product Wine, beer, spirits Alcohol, ethyl carbamate, volatile acids, sulfur dioxide, protein Steam distillation, Kjeldahl,
solid phase extraction (SPE)

For more than 50 years, BUCHI has been developing ingenious solutions for direct steam distillation and Kjeldahl applications. Our solutions include innovative products for the entire process workflow, customized application support, practical apps, and professional maintenance. Tailor-made hardware, software support, and precalibrations underpin the NIRSolutions concept.

Explore BUCHI’s solutions covering

  • the broadest range of applications for steam distillation (alcohol, SO2, volatile acids, protein)
  • more than 50 years of experience in protein determination according to Kjeldahl
  • combined parallel solid phase extraction (SPE) and parallel evaporation for the determination of ethyl carbamate
  • the multi-component quality check of raw materials and final products applying the NIR technology
  • the real-time in-line process monitoring enabled by NIR, VIS and camera sensors

By collaborating closely with our customers, we do everything in our power to make our products, systems, solutions, applications and services as sustainable as possible for people and the environment.

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Voice of the customer:
“The solution for Kjeldahl as well as sulfur dioxide determination in one single instrument is excellent. Moreover the support for application development is very much appreciated.”

Dr. S.S. Marwaha, Chief Executive Officer,
Punjab Biotechnology Incubator, India.

Best@BUCHI #43: Determination of Pear Content in Apple Juice

Best@BUCHI #43: Determination of Pear Content in Apple Juice

Best@BUCHI #43: Determination of Pear Content in Apple Juice

This Best@BUCHI #43 study describes a method for determining of the pear content in fruit (Apple) juices.

By means of the SPE-cartridge module Syncore® Analyst parallel evaporator the number of samples analyzed per day can be increased by three times. The method was assessed successfully with 17 samples, the analytical results of which are detailed and evaluated.

As cider pears have a lower market value than cider apples, it is frequently suspected that apple juice is diluted with the cheaper pear juice. According to Swiss law, apple juice can contain a maximum 10% of pear juice and pear juice a maximum 10% of apple juice. For any other ratios a different designation, e.g. sweet must or fruit juice has to be used, so that the composition is clear for the consumer.

The question posed is how to check that such a regulation has been followed. To ensure the purity of a fruit juice, the SLMB (Swiss Handbook for Food) suggests the analysis of proline.

According to these guidelines, a pure apple juice should contain <15 mg/l of proline, whereas pear juice has a proline content of 30 – 250 mg/l. Additionally, according to the SLMB, pear juice contains higher amounts of sorbitol (averaged 15g/l vs. 4g/l) and higher amounts of citric acid (0.1 – 4 vs. 0.05 – 0.2 g/l) compared to apple juice.

Our own analyses have shown increased concentrations of proline and sorbitol in apple juice, indicating the presence of excess pear juice, but the parameters are unreliable for a quantitative assessment of the actual contents.

The reason for this is that although these compounds are present in both apples and, in higher concentrations, in pears, the natural deviations are relatively high. Thus, these parameters only allow for a more or less qualitative conclusion concerning the actual pear content.

Another group of compounds used for the determination of fruit juice concentrations are the phenolic glycosides. Schieber et. al. describe a method to detect any addition of pear juice by determining the presence of isorhamnetin-3-glucoside. Furthermore Spanos and Wrolstad show that the phenolic profiles of apple and pear juices differ most obviously when comparing the content of 4-hydroxyphenyl-ß-D-glucopyranoside, trivially named arbutin. During subsequent years, other research groups drew the same conclusion. As to the analytic proof, the advantage of arbutin compared to other phenolic glycosides is the fact that the molecule is acid-resistant.

Best@Buchi #55: Determination of PBDEs in Sediment Samples

Best@Buchi #55: Determination of PBDEs in Sediment Samples

Best@Buchi #55: Pressurized Solvent Extraction for PBDEs

This study describes the process of determining PBDEs in sediment samples using pressurized solvent extraction and automated soxhlet extraction. Please download Best@Buchi #55 and review the many other Best@Buchi studies available online.

The efficiency of pressurized solvent extraction (PSE) was investigated by comparing PSE with automated Soxhlet extraction. Sediment samples containing polybrominated diphenylethers (PBDEs) were processed in the Speed Extractor E-914 for PSE and in the Extraction System B-811 for automated Soxhlet extraction. Quantification of PBDEs was performed by GC-MS.

This study shows that both techniques are comparable in terms of accuracy, recovery and reproducibility and confirms that PSE is a much faster technique consuming much less solvent than automated Soxhlet extraction.

PBDEs are organobromine compounds used as flame retardants to improve fire safety in domestic and commercial applications. The production of PBDEs has increased rapidly over the last 30 years due to the growing popularity of personal computers and other electronic equipment.

By 2004, penta- and octa-BDEs were phased out of production by manufactures in the United States and Europe, but deca-BDE continues to be used in high amounts worldwide. PBDEs are non-covalent additives and leach from items through use, volatilization or abrasion and enter the environment. Because of their persistence and lipophilicity, PBDEs enter the food chain and accumulate in biologic tissues. They have been found in the air, soil, oceans, lakes, and in animal tissues throughout the world with increasing levels over time. In humans, contamination was observed in blood, breast milk and fat tissues.

Animal studies show that exposure to PBDEs causes endocrine disrupting effects, affects reproductive processes, reduces immune system performance, and there is also evidence of neurotoxicity.

Best@Buchi 46: Spray Dried Biodegradable Polymers for Controlled Drug Delivery

Best@Buchi 46: Spray Drying Polymers for Controlled Drug Delivery

Spray Dried Biodegradable Polymers for Controlled Drug Delivery

Biodegradable polymers based on polylactide (PLA) and its co-polymers polylactide-co-glycolide (PLGA) were successfully spray dried with the Buchi Mini Spray Dryer B-290. Process parameters are found to prepare spherical particles with a smooth or structured surface.

A literature review demonstrates the feasibility to encapsulate different drugs in biodegradable microspheres for controlled drug delivery systems. Spray dried microparticles have a suitable size and shape for new application fields in pulmonary therapy, cancer treatment or medical devices.

Spray drying is a successfully employed method in pharmaceutical technology to prepare microspheres for controlled drug delivery systems.

Other common methods to produce microspheres are emulsification solvent evaporation, emulsification solvent extraction, or phase separation.

Comparing these methods, spray drying is a simple, rapid, reproducible and easy to scale-up technique. It is a one stage process, allowing mild temperature conditions. The spray drying technique is less dependent on the solubility of the drug (e.g. hydro solubility) and the polymer.

In the last two decades, polymers based on lactic acid and glycolic acid and their copolymers have attracted much interest as carriers in the preparation of different medical devices and drug delivery systems. These polymers meet the necessary criteria of excellent biocompatibility, biodegradability, and non-toxicity in humans – either in surgery or in drug delivery systems.

In pulmonary applications, biodegradable polymers are interesting for inhalation therapy, where the particles sizes have to be smaller than 5.8 microns in aerodynamic diameter. Spray drying has shown its potential use to achieve such small particle sizes.

Please check out all our Best@Buchi studies and also company and product videos on YouTube.

Best@BUCHI #57: Laboratory Scale Spray Drying of Lactose

Lab Scale Spray Drying of Lactose Study

Lab Scale Spray Drying of Lactose

Spray drying is a commonly practiced method to prepare inhalable powders. This study reviews recently published scientific work in the field of lactose spray drying for inhalable applications using Buchi laboratory scale spray dryers. The generations of the Mini Spray Dryer; B-190, B-191 and B-290 models and the new Nano Spray Dryer B-90 are included in the study.

Please contact Buchi for more information on our laboratory scale spray dryers and to download this study.

Spray drying has been applied to a variety of substances, such as peptides, antibiotics, vaccines and biodegradable carrier particles.
The described delivery technology can be used for lung-specific applications to treat cystic fibrosis, asthma, chronic pulmonary infections, lung cancer or tuberculosis.

Lactose is one the most common excipients used for dry powder lung delivery and is approved by the Food and Drug Administration (FDA) for pulmonary delivery, and so, widely applied in aerosolization. This is due to its non-toxic, readily degradable properties after administration. Lactose also has the advantageous material property of a low stickiness behaviour compared to other sugars.

The conclusions include that spray drying is able to produce stable, efficient and inhalable dry lactose powder systems for respiratory delivery with adequate particle size and shape for deep lung deposition.

The Nano Spray Dryer B-90 provides a novel spray drying technique in laboratory scale to prepare submicron particles for pulmonary delivery dry powder formulations.

BÜCHI Labortechnik AG thanks all scientists listed in the references of the study for the remarkable research carried out on BÜCHI spray dryers.