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carbamate, Chromatography Quiz, glyphosate

Chromatography Quiz No.14

Chromatography Quiz #13 Results

We would like to congratulate our grand prize winners of our last newsletter’s Carbamate Analysis Chromatography Quiz: Irene Taylor from Orange County Utilities, Jim Balk from DHHS Public Health Environmental Laboratory, Narjes Ghafoori from LA County Environmental Toxicology Laboratory, Helene Lachance from Shur-Gain Nutreco, and Jamie Palmer and Matthew Hartz from Underwriters Laboratories!!!

laser chess 1They have each won and will be receiving: a Laser Board Game from laser chess 2Sharper Image!  (This strategy-based board game is similar to chess and features an 80-square Egyptian themed grid.  The goal is to protect your game pieces while eliminating your opponent’s by bouncing eye-safe lasers at them through the maze of mirrors you’ve constructed.)

We would like to thank all of you for your submissions!

The correct answer for the modified Carbamate chromatogram: Reagent #2 (CB910, OPA, and Thiofluor) was partially oxidized.  The peak heights of Carbaryl and 1-Naphthol have significant diagnostic importance in regard to the OPA reagent system. Since 1-Naphthol naturally fluoresces, we can eliminate the fluorescence detector as the problem.  Though smaller peak sizes can reflect problems with Reagent #1, since the Carbaryl peak is full-sized, we can deduce that hydrolysis has occurred (Carbaryl naturally fluoresces after hydrolysis).

Particularly astute observation yields additional details about our troubleshooting chromatogram – slightly shifting retention times towards the end of the run could indicate a problem with HPLC hardware, such as a proportioning valve.

Thank you!

Pickering Labs

 Chromatography Quiz #14:

Complete the cross word puzzle below and win a prize!  Simply email your answer (copy of completed puzzle or list answers with clues) as well as your full contact information to Rebecca at rlsmith@pickeringlabs.com by December 15, 2013 in order to win.  You will receive email confirmation that your submission has been received.  The answer to the puzzle and winner congratulations will be published in the next issue (to be anonymous, please notify Rebecca in submission).

Carbamate/Glyphosate Analysis: Cross Word Puzzle

crossword

Uncategorized

34th America’s Cup

By Wendy Rasmussen

OTUSA and ETNZ

Before the America’s Cup came to San Francisco, I never paid much attention to the event. It doesn’t get much press here in the US, and being a native of a land-locked state, sailing was not something I grew up with.

But after living in San Francisco for many years, I learned to sail and gradually my awareness of the America’s Cup increased, and I gained an appreciation of the event and the hard work that goes into designing and sailing the boats.The Cup

Those who wish to race for the cup become Challengers.  If multiple teams are challenging, they must duel it out to decide who will then face the Defender in the America’s Cup Finals.  This series of races became known as the Luis Vuitton Cup. From the America’s Cup Website:

In 1970, more than one yacht club interested in challenging for the America’s Cup, so for the first time, a competition was staged to determine the single Challenger that would face the Defender, the New York Yacht Club.

The French malletier Louis Vuitton became involved with the America’s Cup in 1983, supporting the Challenger Selection Series that came to be known as the Louis Vuitton Cup. The idea was twofold; to develop and identify the strongest possible challenger for the America’s Cup and ensure that they were sufficiently battle-tested through tough competition to beat the Defender.

(Be sure to check out www.americascup.com for information, videos, history, race results and more).

This year, Emirates Team New Zealand (ETNZ) ETNZ low reswon the Luis Vuitton Cup to become the Challenger, sailing against the Defender, Oracle Team USA (OTUSA).

Living in San Francisco, I had the wonderful opportunity to watch several of the races, to meet many of the sailors, and to watch the teams ready themselves for the “big day”. The teams were in town for several months before the regattas to practice. The AC72s were (are) an amazing site to see, both from land and from the water.OTUSA They are truly a sight to behold, especially when foiling at speeds of up to 45kts*

The 34th America’s Cup finals proved to be the longest in history due to several postponements due to wind conditions.  In fact, the official end date for the regatta was September 21; the final race was on September 25th. But perhaps the most amazing feat of this regatta was the comeback made by OTUSA:

In order to win the Cup, a team must earn nine points. Ordinarily, this would mean winning 9 races (1pt per win). But before the regatta began, Oracle were penalized two points due to an infraction in an earlier series. And so while ETNZ needed to win 9 races, OTUSA had to 11. 

The comeback began on Sept 19, 2013. ETNZ were ONE race away from winning the Cup. OTUSA still need to win EIGHT.  For days on end, we all said, “Well, this is it. Kiwi’s are going to take home the cup.” But then OTUSA continuously surprised us all. In the end, they won an unprecedented EIGHT RACES IN A ROW! in order to come back and win the regatta. Click here for the Results.

I won’t speculate here as to why OTUSA made such an amazing comeback, or why ETNZ lost in the end. I will only say that it was so exiting to be a part of that historic moment, in an amazing city with an amazing natural venue for watching the races. And most importantly for me, the members of both teams handled themselves with an incredible amount of dignity and sportsmanship. The members of both teams were all under an incredible amount of pressure, and yet they still managed to greet and sign a few autographs for their fans  — yes, this fan included.

*45kts = 51.8mph. By comparison, our sailboat at it’s fastest will do about 12kts, or 13.8mph

Amino Acid Analysis, AOAC, china, Ninhydrin, pickering laboratories, pinnacle pcx, post-column derivatization, Trione, Whey proteing

Calculation of Whey Protein Fraction in Milk-Based Infant Formula

A method for the calculation of whey protein fraction in milk-based formula products was developed and validated by a group of researchers from Abbott Nutrition, Covance Laboratories and AOAC International. The method is based on calculating the ratio of (Asx + Ala)/(Pro+Phe) determined from the amino acid profile of the hydrolyzed sample.

The method was approved as AOAC Official First Action Method 2012.07 and is appropriate for accessing compliance with whey content requirements of GB 10765-2010 (National Food Safety Standard Infant Formula)*. It is applicable to finished products containing both intact and partially hydrolyzed whey proteins.

According to this method, the Amino Acid Profile of hydrolyzed samples is determined using cation-exchange chromatography with post-column derivatization and UV/Vis detection. The researchers used Pickering Laboratories post-column derivatization system, our patented Trione Ninhydrin reagent and Pickering Sodium analytical column and buffers.

The method performance was evaluated using non-fat dry milk and products with whey levels from 32% to 63%, including NIST Infant Formula Standard Reference Material. The repeatability ranged between 0.3 and 2.5 %, while intermediate precision were between 2.6 and 3.4%. Average recoveries ranged from 97 to 100%.

The unmatched accuracy and precision of amino acid analysis by HPLC with post-column derivatization allowed the researches to develop a robust mathematical model for calculating whey protein fraction that can be successfully applied to a wide range of products. This proved once again that post-column derivatization analysis of amino acids is still a method of choice for laboratories that require highly accurate results.

Pickering Laboratories offers a total solution for amino acids analysis, including post-column derivatization systems, reagents, columns, buffers and standards.

The reference to the published study is below. The First Action Official Method 2012.07 can also be found online at http://www.eoma.aoac.org/.

Calculation of Whey Protein Fraction in Milk-Based Infant Formula: First Action 2012.07

Authors: Wesley Jacobs, Paul Johns, Phillip Haselberger, Joseph J. Thompson, Darryl Sullivan, Steve Baugh.

Source: Journal of AOAC International, Volume 96, No. 3, 2013, pp. 502-507

 

(*) this is a Chinese Standard

amino acid, Amino Acid Analysis, pickering laboratories, pinnacle pcx, Post-column, post-column derivatization, Trione

Amino Acid Analysis of Cell Culture Media

We have a new Method Abstract! MA371, Amino Acid Analysis of Cell Culture Media

Cell cultures are widely used to produce biopharmaceuticals and other biologically active compounds. The composition of the cell culture media affects the yield and structure of the desired products and must be carefully optimized. Cell culture media is typically composed of mixtures of amino acids, vitamins, carbohydrates, inorganic salts as well as different peptides, proteins and other compounds. As the cells grow, they consume nutrients and release target biopharmaceuticals as well as waste products.

Amino Acids serve as the building blocks of proteins, as well as intermediates in many metabolic pathways. Amino Acids are typically added to cell culture media to provide nutritional requirements for the cells. Monitoring and adjusting Amino Acid composition is an essential part of optimizing the manufacturing process to ensure high quality and optimum yield of the final product.

Amino Acid Analysis using cation-exchange chromatography with post-column Ninhydrin derivatization allows for easy determination of Amino Acid concentrations in many complex matrices, including cell culture media. The post-column method is very sensitive, reproducible and rugged. It has been and continues to be a method of choice for laboratories running biological samples, protein, peptides and foods analysis. Most chemical compounds present in the media do not interfere with analysis, so the majority of samples only need diluting with citric buffer and filtering before analysis. If serum is added to the media, then the proteins need to be precipitated using either Seraprep™ solution or ultrafiltration.

Pickering Laboratories, Inc. offers the complete solution for Amino Acid Analysis, including post-column derivatization instruments, columns, eluants, reagents and standards. The Pinnacle PCX derivatization system has a programmable column oven to allow for shorter run times and easy method optimization.

YChromatograms of Cell Culture Mediaou can download this application note, and many others from our website: www.pickeringlabs.com

METHOD
Analytical conditions
Column: High-efficiency Lithium cation-exchange column, 4.6 x 75 mm, Catalog Number 0354675T
Flow Rate: 0.55 mL/min
Mobile Phase: See method in Table 1

Post-Column Conditions
Post-column System: Pinnacle PCX
Reactor Volume: 0.5 mL
Reactor Temperature: 130 °C
Flow Rate: 0.3 mL/min
Detection: UV/VIS 570 nm for primary amino acids, 440 nm for secondary amino acids
Injection Volume: 10-50 uL

gradient table for AAA

AOAC, HPLC, pickering laboratories, pinnacle pcx, post-column derivatization

Polyether Antibiotics in Animal Feed

Our updated Method Abstract 264 describes the analysis of Monensin, Salinomycin, Narasin, & Lasalocid in Animal Feeds.

Polyether Antibiotics are commonly used for preventing coccidiosis and other infections in poultry and for improving feed efficiency for beef cattle and swine. The use of Polyether Antibiotics is strictly regulated, with only specific ionophores approved for use in feeds intended for different animals.

Analysis of Polyether Antibiotics by HPLC with post-column derivatization and UV/Vis detection has been proven to successfully identify and quantify Monensin, Narasin and Salinomycin in medicated feeds, supplements and premixes as well as to determine trace contamination levels in non-medicated feeds [1, 2].

Post-column derivatization of Polyether Antibiotics is done using highly acidic Vanillin or DMAB reagents. The Pinnacle PCX derivatization system (Pickering Laboratories, Inc.) has an inert flow path and automated system wash capabilities that make it uniquely suitable for handling corrosive reagents. The two-pump system is recommended to extend reagent stability, but the single-pump system for this application is also available.

Adding a Fluorescence detector to the instrumentation allows for using the same extraction procedure and HPLC conditions to also determine Lasalocid, which doesn’t require post-column derivatization.

Chromatograms of Polyether AntibioticsMETHOD
Sample Preparation
To 25 g of finely ground feed sample, add 100 mL of extraction solution (90% Methanol – 10% water). Shake for 1 hour at high speed using a mechanical shaker. Let the solids settle and filter an aliquot of the extract for injection. Dilute with extraction solution if needed to fit the calibration curve. Use a 2.5 g portion when testing premixes.

Analytical conditions
Analytical Column: Polyether Column, C18, 4.6 x 250 mm, Catalog No 2381750
Temperature: 40 ºC
Flow Rate: 0.7 mL/min
Mobile Phase: 90% Methanol, 10% of 5% Acetic Acid solution in water, isocratic
Injection volume: 20 μL

Post-Column Conditions
Post-column System: Pinnacle PCX
Reactor Volume: 1.4 mL
Reactor Temperature: 90 °C
Reagent 1: Concentrated Sulfuric acid / Methanol (4:96 v/v)
Reagent 2: 60 g of Vanillin in 950 mL of Methanol
Reagent Flow Rate: 0.3 mL/min
Detection: UV/VIS 570 nm (for Lasalocid – FLD, Ex. 322 nm, Em. 370 nm)

Conclusion
Analysis of Polyether Antibiotics by HPLC with Post-column derivatization is a robust and sensitive method that utilizes standard equipment and could easily be adopted by testing laboratories. It allows for testing of different ionophores at wide range of concentrations,
including at trace levels. Using Pinnacle PCX post-column derivatization system, factory configured for the analysis, guarantees stable and reproducible results.

The full application note as well as our complete Product Catalog can be downloaded from our website: www.pickeringlabs.com

table for polyether antibiotics

carbamate, clean-up, eluvac, freestyle, glyphosate, GPC, NEMC, pinnacle pcx, post-column derivatization, Uncategorized

NEMC 2013

Pickering Laboratories participated in the National Environmental Monitoring Conference in San Antonio, Texas from August 4-8.

niosita low res
Old San Antonio

Rebecca and Wendy were on-hand to share Pickering’s products with the environmental laboratories involved with the conference.  On display were the new FREESTYLE sample clean-up system and the Pinnacle PCX.

Some highlights of the conference included a new product by InnovaPrep, which will rapidly concentrate pathogens in liquid samples, and the 2-D GCMS analysis of POPs in human milk. There were also several interesting discussions about pesticide extraction and analysis as well as the use of Hydrogen as a carrier gas in GC (instead of Helium, for which there is currently a shortage).

The meeting was held at the Hyatt in downtown San Antonio on the Riverwalk. This area of town is full of history and interesting architecture. We were also located directly across the plaza from the Alamo.

alamo low res
Remember the Alamo
aflatoxin, Amino Acid Analysis, amino acids, antioxidants, artificial perspiration, clean-up, deoxynivalenol, freestyle, glyphosate, GPC, immunoaffinity cleanup, mycotoxin, natural toxins, New Products, pickering, pickering laboratories, pinnacle pcx, post-column derivatization, Uncategorized

2013 Pickering Laboratories North American Catalog

Our latest Catalog for North America is now available!

Click on the link to download the latest product Catalog from Pickering Laboratories, Inc.

Pickering Catalog: http://pickeringlabs-retentiontimes.com/wp-content/uploads/2013/08/2013_PickeringLabs_Catalog_NorthAmerica_LowRes.pdf

Inside our catalog you will find a complete product listing for all instruments and consumables we currently have available. From Sample Cleanup to Post-Column Derivatization, to artificial Perspiration and Saliva, we hope you find something you will find useful!