All posts by Pickering Laboratories

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.

NACRW 2017 Student Scholarships

The deadline is April 21, 2017

We are pleased to announce that NACRW will again be offering five student stipends—where undergraduate and graduate students can apply, and, if chosen, will receive a $500 stipend for travel to the NACRW 2017 conference.

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If you have any questions, please contact Sareeta Nerkar (organizing committee member for NACRW) at sareetan@pickeringlabs.com.

Information to submit an abstract and register for the workshop are now available online at www.nacrw.org.

  • Advanced detection techniques
  • Advanced sample preparation
  • Novel and Emerging Food Contaminants
  • Veterinary Drugs and Anti-microbial Resistance
  • Residue Analyses in Aquaculture Products
  • Mass Spectrometry Forum: MS applications, challenges 
  • and solutions
  • General Topics
  • Natural Products, Supplements, and Cannabis
  • Updates from USA State/Federal government: agricultural, environmental and health laboratories

For more inforation, please click here.

 

 

A Legacy of Guaranteed Chemistry

By Rebecca Smith, Director of Operations

As most of you have already learned from Jim Murphy in his earlier notifications, our founder and friend Dr. Michael Pickering has passed away.  He is survived by his wife, Judy Pickering, who will now assume ownership of the company.  Michael also leaves behind four children and six grandchildren. 

At the lab, Michael leaves a legacy of another kind.  Pickering Laboratories is a unique place to work, bonded by a strong family feeling and staffed by dedicated employees.  Michael was always the chemist behind the company and from early on he created an unprecedented industry standard: he set out to provide Guaranteed Chemistry. 

Michael started the lab with a background in Amino Acid Analysis and a fantastic improvement on the traditional Ninhydrin reagent.  Our flagship product TRIONE® kicked off the company, but Michael soon expanded into post-column instrumentation kits and other applications.  As his reputation developed as the post-column expert, he began receiving calls from other labs trying to fix different post-column methods.  And Michael loved being challenged by technical problems, so from there our environmental applications were born.  Michael set out to understand the impossibilities with the early EPA methods for Carbamates and Glyphosate, and improve the functionality (and solubility!) of those methods for chemists around the country.  Eventually Michael and his early customers succeeded in updating EPA methods 531 and 547, and a new generation of chemists was grateful (myself included).

When I was originally hired by Pickering Labs, it was as Michael’s research assistant.  And as I try to think of personal anecdotes to share, what I am mostly struck by is that every single person who conversed with Michael has a personal anecdote.  He was a charming and enthusiastic conversationalist.  Michael was both a brilliant chemist and a lover of art, books, food and film.  In any given workday, I would be as likely researching a new sulfonation of a potential reagent as I would be looking up an old Marlon Bando movie (and adding it to my Netflix queue).  We talked about Salvador Dali exhibits he’d seen and about longstanding friendships he cultivated with chemists around the world.  Michael genuinely bonded with everyone he encountered – and I can hazard a guess that if you’d ever had Michael in your lab troubleshooting, I’ve heard about you, your family, your favorite book, what your analytical problem was and how he fixed it.  Michael told great stories, and I hope you had the opportunity to hear one or two from him over the years.

As 2017 marks our 35th year in business, we are striking out on perhaps our most difficult chapter as Michael’s absence will be poignantly felt.  But we hope to heal through our work and honor his legacy by building relationships and solving technical problems for decades to come.  

Please do us the great favor of raising a glass and toasting to a wonderful man.  We celebrate Michael and the years of joy and memories he gave us.

Cheers,
The Pickering Labs Team

 

Chromatography Quiz #26

Chromatography Quiz #25 – B@$eL!nE Noise! — Results

Pickering Labs would like to congratulate the winners of our last newsletter’s Baseline Noise Quiz: Joel Fray from Colorado Analytical Laboratories, Jim Balk from Nebraska DHHS Public Health Environmental Laboratory, Narjes Ghafoori from LA County Environmental Toxicology Lab, Hossein Hajipour from Texas Dept. of Health Services Laboratories, and Tom Schneider from Suffolk County Water Authority.

They have each won and will shortly receive a decadent Chocolate Dream Gift Basket! Created by Cherry Moon Farms, this lovely basket is the ultimate assortment of chocolate sweets that will surely delight! Congrats to our quiz winners and enjoy the goodies!

Thank you all for your submissions! 

The correct answer to the Amino Acids Baseline Noise Quiz:

The zoomed baseline exhibited sine wave with regular oscillations at frequency of about 6 sec. This type of pattern is characteristic to HPLC pump noise as reciprocating HPLC pump moves to deliver the flow of eluants through the column.  If pump is operating normally, the oscillations are very small and will not show as baseline noise. But if the pump has dirty/bad check valves or old/poorly installed seals, the noise increases. In our case, the HPLC pump check valves were bad and needed replacement. 

Chromatography Quiz #26: Shifting Retention Times – Carbamates

What is causing the retention time shift in the chromatogram below?  Simply email your answer as well as your full contact information to Rebecca at rlsmith@pickeringlabs.com by May 1st, 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). 

Carbamates Analysis – Shifting Retention Times

Pinnacle PCX post-column instrument is being used, in a traditional HPLC setup as recommended by Pickering Laboratories. The quiz question: what is causing the shifting retention times? 

Post-column conditions for carbamates analysis:

Reagent 1: CB130
Reagent 2: CB910/Thiofluor/OPA
Reactor: 100 °C, 0.5 mL
Reagent flow rate: 0.3 mL/min
Injection volume: 10uL

FLD Settings:

λex 330 nm
λem 465 nm

HPLC Flowrate: 1.0 mL/min
Column Temperature: 42 °C

Good Chromatogram

Bad Chromatogram

 

Glyphosate Testing Updates

1-cornBack in May, we reported on new developments in food testing and the beginning of FDA (Food and Drug Administration) participation in testing for Glyphosate residues in food.  This new FDA directive was in line with growing international concern over the safety of Glyphosate, and increased domestic pressure from consumer groups, academics and testing laboratories.  Pickering Laboratories has been excited to assist our Glyphosate-testing environmental customers with learning the new food matrices, and our food testing customers with learning a new Glyphosate application.

During the September 2016 AOAC International meeting in Dallas, Pickering Laboratories presented an improved post-column method for Glyphosate analysis in foods with simplified sample preparation procedure. This method was successfully applied to Glyphosate analysis in oats, wheat flour, eggs, milk, soybeans, corn and beer. The method is capable of analyzing Glyphosate at levels well below legal limits with high precision and accuracy. Our poster generated a lot of interest among AOAC meeting attendees. We received inquiries from laboratories doing pesticides testing as well as other attendees who, despite not being involved in Glyphosate analysis, expressed concerns at the indications of presence of Glyphosate in common foods, especially cereals. A copy of our application note can be found on our webpage.

Legal tolerances for Glyphosate vary widely from country to country. For example, the limits for oatmeal range from 0.1 ppm in Australia to 15-20 ppm in Canada, Europe and United States. In May 2016, Taiwan recalled close to 62,000 kg of Quakers Oats products due to Glyphosate contamination with up to 1.8 ppm present. Other reports also indicate that Glyphosate contamination of oat-containing and wheat-containing cereals is commonly found at levels close to and above 1 ppm. These findings are not surprising considering prevalence of Glyphosate use as a pre-harvest desiccant for many crops (including oats and wheat). Though 1-2 ppm levels of Glyphosate are well below the legal tolerances within the United States, the amount of cereals commonly consumed by people, including young children, range from 50-100 grams per day. Those quantities easily bring a person’s daily exposure to Glyphosate to almost 0.2 mg, and that is just from breakfast.

In light of mounting evidence of the pervasive presence of low levels of Glyphosate in a wide variety of common foods, we find it unfortunate that the FDA reportedly has halted the testing of Glyphosate in food products, citing the need to develop consistent methods amongst the different FDA laboratories. On the other hand, the European Food Safety Authority (EFSA) reported proposing to extend their pesticide residue monitoring program, with special attention to Glyphosate monitoring, including mandatory analysis of Glyphosate in crops such as soy beans, rapeseeds (Canola) and barley. We certainly hope the FDA would follow suit and Glyphosate food testing will soon resume. We believe Pickering Laboratories’ method would be a perfect candidate for the Glyphosate monitoring program.

2016 AOAC International

aoac-2016The 130th Meeting of AOAC International was held in Dallas, Texas from September 18-21, 2016. Pickering Laboratories is a long time corporate sponsor and very active participant in the expert panels and laboratory collaboration groups that characterize the spirit of the AOAC members.  Maria Ofitserova attended to present our validated post-column derivatization method for Theanine Analysis in Tea, Dietary Ingredients and Supplements, and her Monday morning session drew a large audience of interested attendees. This Theanine method was approved as AOAC First Action Official Method 2016.10 in August 2016 and has just been published together with the Single-Laboratory Validation results in the November-December issue of Journal of AOAC International.

Pickering continued to be closely involved in AOAC Standards development work by participating in several Stakeholders Panels. As a member of the SPIFAN Expert Review Panel (ERP), Maria attended the meeting and focused on reviewing candidate methods for nutrients and trace elements in infant formula and adult nutritionals. The ERP discussed methods for B vitamins, Carotenoids, fructants and galacto-oligosaccharides. She also attended the meeting of Stakeholder Panel for Dietary Supplements (SPDS), where three new working groups were launched! These working groups are tasked with developing Standard Method Performance Requirement for the analysis of free amino acids, vitamins K1 and K2 as well as active compounds in ginger.  

Among the new application notes we introduced at the show was the updated Application Note MA211 Glyphosate Analysis in Foods, which generated interest for a number of attendees.  Please read our Glyphosate testing update in this newsletter to find out more!

The SupplySide International Trade Shows & Conferences

1-supplmentThe SupplySide International Trade Shows & Conferences brings together global dietary supplement, food and cosmeceutical companies and ingredient suppliers. The shows represent the largest exhibitions of raw materials and services for the nutraceutical and functional food industries. The Supply Side West 2016 took place in Las Vegas from October 4 to 8 and focused on the new dietary ingredient notification process. This focus strengthened the importance of Good Manufacturing Practices and labelling procedures. Some controversial supplements included Aloe, Hemp and Cannabis, which were discussed in length related to confusion in definitions, plant parts used and classification of active ingredients.  The American Herbal Products Association website (https://bsh.ahpa.org/HomePage.aspx) has more information regarding these topics and the website also includes The Botanical safety handbook. This handbook together with the Dietary Supplement Fact sheets (https://ods.od.nih.gov/) helps consumers make educated decisions regarding supplements. Pickering Laboratories interest in this growing industry is to provide support and options to analytical methods using post-column technology. Our post-column derivatization instruments (Pinnacle PCX and Vector PCX) combined with the relevant kits ( analytical column, mobile phase, reagent) can be used to analyze contaminants such as pesticides (Carbamates), herbicides (Glyphosate) and mycotoxins that are harmful to consumers and active ingredients such as amino acids. Details for these methods can be found at https://www.pickeringlabs.com/library/.