All posts by Pickering Laboratories

Latin-American Pesticide Residue Workshop 2017

Pickering at the LAPRW 2017

This year, David Mazawa and Rebecca Smith traveled to and participated in The 6th Latin-American Pesticide Residue Workshop: Food and Environment (LAPRW 2017), which took place from May 14-17 in San Jose, Costa Rica. The location was perfect for discussing the global impact of environmental residues: Costa Rica protects over a quarter of all its land in national parks, wildlife refuges and reserves. And the country boasts nearly 6% of the entire world’s biodiversity!

Costa Rica is home to Macaws and hundreds of other beautiful birds.

This workshop continued building on the success of the previous five LAPRW workshops by keeping scientists and regulators informed about the advances in pesticide residue regulation in food and the environment, methodologies of analysis, instrumentation, risk analysis, monitoring, and quality control assurance of laboratories.

Three toed sloth, hanging out.

Pickering Laboratories, Inc. is proud to sponsor and support this great conference. We would like to thank the organizers: Centro de Investigación en Contaminación Ambiental (CICA) and different units of the Universidad de Costa Rica (UCR) and the Servicio Fitosanitario del Estado (SFE) of the Ministerio de Agricultura y Ganadería de Costa Rica (MAG). Their hard work and dedication really showed in the quality of the conference and this workshop wouldn’t have been possible without them.

David at the Pickering Booth, reviewing the exciting technical program!

After an exciting week of technical talks and networking with scientists from around the world, we came back to the lab with great contacts, and several new ideas for how to best serve our international customers.

We look forward the next LAPRW workshop at Iguazu Falls, Brazil!

Pittcon and Presenting Product Testing!

Pickering Laboratories exhibited at the 67th Pittcon annual conference, which was held March 5-9 in Chicago this year. Pittcon is the leading exhibition for laboratory science and new technology in food safety, life science and emerging markets.  As we have for the last 30 years, Pickering Laboratories exhibited as the leader in Post-Column applications and technology.

As perhaps an unexpected addition, we splashed Pittcon with the introduction of our Pickering Test Solutions product line.  The varied audience of Pittcon was ideal for the diverse applications of our product testing solutions and we received a warm reception.  Thank you to everyone who stopped by the booth for more information!

To celebrate our artificial perspiration Pittcon debut, we worked up a sweat by raffling a Fitbit Flex twice daily.  (Congratulations again to the winners of the Fitbits!)  Our sweat themed giveaways of exercise towels and workout headbands made a nice complement to our classic post-column rulers, and overall we felt we informed and entertained our fellow attendees.

As mentioned, the Pickering Test Solutions product line was of active interest to many of the Pittcon attendees. Among the industries interested in these product test solutions were: tobacco, electronics, surgical instruments, materials science, pharmaceutical dissolution testing and others.

Our product testing solutions include:

  • Artificial Perspiration
  • Artificial Saliva
  • Artificial Urine
  • Artificial Sebum
  • Artificial Cerumen

If you don’t see what you need, just ask!  Customer requests for specific regulation or standard formulations of an artificial body fluid often result in new additions to the product line. We also produce numerous proprietary formulations that are custom made for our customers’ in-house needs, which you won’t find in our publicly available catalog.

Our core post-column business is still going strong.  New and highlighted applications included:

  • Theanine in Tea
  • Glyphosate in Foods
  • Carbamates in Foods
  • Formaldehyde
  • Amino Acids in Pharmacopoeia 8.0

Glyphosate testing is a major focus of our research initiatives this year as the activity surrounding Glyphosate worldwide has increased. The application note MA 211 Glyphosate Analysis in Foods  addresses concerns that Glyphosate has been found in the finished food products available to consumers, and corresponding to media attention resulting in the FDA considering testing for Glyphosate in finished foods.

Pickering Laboratories is an active participant in the AOAC method development and has been for many years. Our latest collaboration MA 378 Analysis of L-Theanine in Tea by HPLC with Post-Column Derivatization was approved by the Expert Review Panel as an AOAC First Action Official Method for the analysis of Theanine.  The method can be implemented by laboratories for analysis of a wide range of complex green tea-containing dietary supplements in forms of powders, tablets, tinctures, gelcaps, softgels and capsules. This official method has been published in the Journal of AOAC International.

We always enjoy visiting with our customers, distributors and other Pittcon attendees though the show.  Thank you again for your visits and for your business over the years!

Cannabis Research and Resulting Poster and Application Note

Broader acceptance of medical cannabis use increases the need for analytical methods capable of determining the active compounds of cannabis as well as for methods to detect contaminations, such as pesticide residues, mycotoxins and traces of organic solvents. Cannabinoids are a class of terpenophenolic compounds that are associated with the pharmacological activity of cannabis. Cannabinoids exist in the plant mainly as carboxylic acids that are not physiologically active. They are converted to neutral analogs by light and heat while in storage or during the preparation of edible products. Acids are also converted to neutral analogs during GC analysis, which often causes differences in results when comparing with HPLC methods.

We developed a new post-column derivatization method to analyze cannabinoids in cannabis plants as well as in cannabis-containing edible products. This post-column method is based on reaction with Fast Blue Salt reagent under basic conditions, a well-known color-forming reaction that is used in drug tests to detect cannabinoids via test-tube methods and thin-layer chromatography. Detection at 475 nm is performed using a UV/Vis detector.

Our method implements a simple extraction with acidified water/acetonitrile followed by QuEChERS sample clean-up. The same procedure is applicable to both plant materials and edible products containing cannabis. The method is suitable for analysis of the major neutral cannabinoids such as THC, CBD, CBN and CBG as well cannabinoid acids THCA-A and CBDA with high sensitivity and selectivity of detection.

Chromatography Quiz #27: Only AMPA

Chromatography Quiz #26: Shifting Retention Times – Carbamates — Results

Pickering Labs would like to congratulate the winners of our last newsletter’s Shifting Retention Times–Carbamates Quiz: David Green from Pepperdine University, Jeff Fan from Cumberland Valley Analytical Services, Karissa Scroggins from North Coast Laboratories, Jim Balk from Nebraska DHHS Public Health Environmental Laboratory, Narjes Ghafoori from LA County Agricultural Commissioner Weights & Measure Environmental Toxicology Lab, Tom Schneider from Suffolk County Water Authority, and Ms. Widchuda Meeim from Thailand Bureau of Quality Control of Livestock Products.

They have each won and will shortly receive a Williams Sonoma BBQ Tools Set! Included in a stainless-steel case for easy storage, these sleek grilling tools are perfect for those upcoming summer cookouts!

Congrats to our quiz winners and happy grilling!

Thank you all for your submissions! 

The correct answer to the Sifting Retention Times – Carbamate Quiz:

Leaking proportioning valve. The leaking proportioning valve improperly mixed the method gradient and didn’t have enough methanol which caused the analytes to elute late.

Chromatography Quiz #27: Only AMPA

What is causing the bad chromatography in the example below?  Simply email your answer as well as your full contact information to Rebecca at by September 1, 2017 in order to win.  You will receive email confirmation that your submission has been received.  The answer to the quiz and winner congratulations will be published in the next issue (to be anonymous, please notify Rebecca in submission). 

Glyphosate Analysis – Only AMPA

Pinnacle or Vector PCX post-column instrument is being used, in a traditional HPLC setup as recommended by Pickering Laboratories. The quiz question: what is causing Glyphosate to disappear?  

Post-column conditions for carbamates analysis:

Reagent 1: GA116
Reagent 2: o-Phthalaldehyde and Thiofluor in GA104
Reactor: 36 °C, 0.5 mL
Reagent flow rate: 0.3 mL/min
Injection volume: 10uL

FLD Settings:

λex 330 nm
λem 465 nm

HPLC Flowrate: 0.4 mL/min
Column Temperature: 55°C


Good Chromatogram

Glyphosate Test Mix, 2.5ppm, 10µl Injection

Bad Chromatogram only shows AMPA peak. No Glyphosate peak can be detected.

Glyphosate Test Mix, 2.5ppm, 10µl Injection


Pickering Laboratories presents new products at PITTCON 2017

Chicago, McCormick Convention center, March 5-9. Booth # 2625

Pickering Laboratories will be exhibiting at the 4-day event and meeting with customers and distributors to highlight new applications and products from the Product Testing Solutions and Post-Column Derivatization product lines.

New Post-Column Applications:

  • Theanine
  • Glyphosate in Foods
  • Carbamates in Foods
  • Formaldehyde
  • Amino Acids in Pharmacopoeia 8.0

Our Product Testing Solutions include artificial Body fluids manufactured testing made to official industry protocols:

  • Artificial Perspiration
  • Artificial Saliva
  • Artificial Urine
  • Artificial Sebum 
  • Artificial Cerumen

Also we are announcing our new Artificial Sebum and Sweat Emulsion product!

Twice-a-day raffle to win a Fitbit Flex – come to Booth 2625 and get into the game!


Glyphosate Banned in France and Labeled a Carcinogen in California

Events surrounding Glyphosate testing in foods continue to evolve with the latest stories “France banning Glyphosate sales in consumer nurseries” and “California requiring labeling Glyphosate as a carcinogen.” We also want to discuss the EU- wide petition to ban Glyphosate.

After an arm of the U.N.’s World Health Organization (WHO) identified the main ingredient in Monsanto’s popular weed killer Roundup as “probably carcinogenic to humans,” France has taken a step to limit sales of the herbicide.

A judge tentatively ruled that California can require Monsanto to label its popular weed-killer Roundup as a possible cancer threat despite an insistence from the chemical giant that it poses no risk to people.

The European commission says it has received a European Citizens’ Initiative (ECI) – essentially a petition put together by EU citizens – proposing a ban on the controversial pesticide Glyphosate. The proposal is being supported by a number of environmental groups, and according to the rules ECIs need to be submitted by a committee which includes representatives from at least seven EU member states. The initiative calls on the commission ‘to propose to member states a ban on Glyphosate, to reform the pesticide approval procedure, and to set EU-wide mandatory reduction targets for pesticide use’. Several environmental organizations, including Greenpeace and the Pesticide Action Network, have already voiced their support.

Here are links to our earlier posts, if you’d like to catch up on the backstory:

Pickering Laboratories’ Glyphosate testing in foods.

FDA halted the testing of Glyphosate in food products. No time given for resumption of the testing.

EFSA: Pesticide risk to consumers remains low.

The EPA was to hold public meetings Oct. 18-21, 2016 on the safety of Glyphosate. These meetings were postponed over industry objections to the panel members.

The EPA global risk assessment of Glyphosate has been removed from the website. Already two years late, the best estimate now for publication is April 2017 said an EPA spokesperson.

The European Food Safety Authority (EFSA) has tested 83,000 food samples for pesticides and reported that most were within safety standards for pesticides residues.


Post-column Method for Analysis of Theanine in Tea

Pickering Laboratories has reported earlier that we developed and validated a post-column method for analysis of Theanine in tea (Camellia sinensis) dietary ingredients and supplements. Theanine is the main naturally occurring amino acid found in tea and it is responsible for a number of health benefits of tea as well as for its savory pleasant taste. 

The analytical method was developed in response to call for methods issued by Stakeholders Panel for Dietary Supplements. The method implements a simple extraction procedure without any clean-up steps and uses cation-exchange chromatography and post-column derivatization with Ninhydrin reagent to separate and detect Theanine.

Pickering method was approved by Expert Review Panel as AOAC First Action Official method for analysis if Theanine and can be implemented by laboratories for analysis if wide range of complex green tea-containing  dietary supplements in forms of powders, tablets, tinctures, gelcaps, sofgels and capsules.

The method and validation results are published in Journal of AOAC International:

J AOAC Int. 2016 Nov 1, 99(6), 1470-1478.

Maria Ofitserova, Sareeta Nerkar

Analysis of Theanine in Tea (Camellia sinensis) Dietary Ingredients and Supplements by High-Performance Liquid Chromatography with Postcolumn Derivatization: Single-Laboratory Validation, First Action 2016.10.