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Pickering Laboratories at the Florida Pesticide Residue Workshop

By Wendy Rasmussen

Last month we participated in the Florida Pesticide Residue Workshop, held in St. Pete’s Beach in Florida from July 18-21. It was a very interesting meeting from many aspects: talks, posters, mix of attendees and exhibitors, current topics. There were talks on mycotoxins and veterinary drugs as well as policy and risk assessment.

Pickering presented a Vendor breakfast session on Wednesday July 21, titled “Keys to an Analytical Method: Focus on Mycotoxins” We decided to highlight our Mycotoxin analysis product line which we are distributing from our German partners, LCTech GmbH

The weather was unusually cool for Florida in July, hovering in the mid-90s (35°C). The water temperature in the Gulf was surprisingly refreshing at “only” 89°F (32°C). The usual thunderstorms were present, although fewer in number. Mother Nature provided us with some very impressive lightning storms just off shore in the evenings.

The meeting was much larger this year, both in terms of attendance and exhibitors. Not only were there more attendees, but there was a very large number of First-time attendees, as well as a greater contingency of international attendees from Europe, Asia, Australia, and South America. There were 226 attendees and 25 exhibiting companies.

One of the hot topics of discussion at the meeting was the Deepwater Horizon spill in the Gulf. No oil
has reached that part of the Florida coast, and so the beaches were open, but inside there was much debate about the testing of the seafood for PAHs, the cleanup of the spill, and the environmental impact, both on marine human life. There was a great deal of discussion about using the NOAA method for PAHs (which involves GPC Cleanup), as well as testing for the alkyl homologs present in the oil and potential screening methods to speed up the analysis time.

GPC cleanup remains very effective at cleaning up fatty and complex matrices, and it’s still part of the official methods. GPC Quattro would be an excellent choice for this. With 4 individual channels, each with their own pump and lines, and with rugged, easily repackable columns, a lab would get 4 times the productivity of a single column system: GPC Quattro

Links for info on the Gulf:
There is an abundance of websites, news, and general information about the oil spill. Here are a few links I found to be interesting:

The FDA has approved an HPLC-FLD screening method for the PAHs, which will still need confirmatory testing, but this will decrease the initial testing time down from 4-5 days to 48hrs.
For FDA’s latest updates:

It’s been proposed that we should be looking at Alkyl Homologs of PAHs. Ed Overton gives a pretty good overview of these compounds and the composition of oil spills in general: Overton perspective

Restek recently analyzed some of the oil via GCxGC-TOFMS: ChromaBLOGraphy

(This is not meant to be a comprehensive list, nor is there any endorsement intended or implied)

Please Re-submit Your Answers to Amino Acid Quiz (No. 2)

Due to an unfortunate set of circumstances, all submitted answers to the previous Chromatography Quiz on Amino Acid Analysis have been lost. We sincerely apologize for the inconvenience to everyone who submitted an answer, and ask for all entries to be resubmitted. As we genuinely regret our technical difficulties, Rebecca will be sending prizes to all submissions, and grand prizes to everyone with the correct answer. Please resend your email, or resubmit your answer to Rebecca will send you confirmation via email that she has received your submission. All entries will be reviewed on June 11th, and prizes will be sent at that time. You can review the quiz at: Again, our apologies, and if you have any questions please contact Wendy or Rebecca at 650-694-6700.

Chromatography Quiz No. 1: Carbamate Analysis for US EPA 531.1

Chromatography Quiz No. 1:

Special Note: This is the first Quiz included with our newsletter. For each issue, we’ll choose a chromatogram from a different application or industry. So if Carbamates don’t apply to your lab this round, stay tuned!

To Win:
Simply email your answer and your full contact information by December 1st to Rebecca Smith at email Rebecca Smith

The troubleshooting answer and winner congratulations will be published in the next issue.

Chromatography Quiz
Identify the error made when running the Carbamate chromatogram below and win a prize!

Pickering Standard: 1700-0063 Carbamate Test Mix, 2.5 µg/mL, inject 10 µL
Pickering Column: 1846150 Carbamate Column, C18, 4.6 x 150 mm

Normal Operating Conditions (for reference only, condition changes may be reflected in chromatogram):

Column Temperature: 42 °C
Flow rate: 1 mL/min
Eluent Gradient:

Normal Operating Conditions


Post-column conditions for pesticide analysis:
Reagent 1: Hydrolysis reagent CB130
Reagent 2: 100 mg of OPA, 2 g Thiofluor™ in 950 mL of CB910Reactor 1: 100 °C, 0.5 mL
Reactor 2: ambient. 0.1 mL
Reagent flow rates: 0.3 mL/min
Detection: Fluorometer ex 330 nm, em 465 nm

Post-column conditions for pesticide analysis