Category Archives: 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

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

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!

Pickering Laboratories in 2013

By Wendy Rasmussen

In recent years, we have released several new products and applications, and with still more on the horizon, it occurred to me that now would be a great time to summarize the Pickering of today – our mindset and our wide variety of products & applications.

Acai Berries
Acai Berries

No longer are we simply the “Post-Column Company”. We are the “Automated-Sample Antioxidants” company.  Think of us as the new “super fruit.” The Acai berry, or perhaps the new Chia Seeds (incidentally, we do have a post-column application for the identification & quantitation of  Antioxidants in a variety of matrices).

We are still very active, and we as a company plan to be here for many years to come. We are still the company founded on chemistry and a desire to to teach, to spread our technical expertise, to support our customers.

It’s been a few years now since Pickering began distributing and supporting our LCTech Product line.  The products have shown an ever increasing interest here in the US and in Canada (our official Sales Territory for this product line). We are very proud to offer these products and we hope we can develop it further in the future.

Historically, we have provided the back-end of an analysis (post-column derivatization). Nowadays, we can provide the front-end of analysis as well (the sample-cleanup).

In thinking about our product offerings, I realized that a simple list does not effectively show the scope of the products we have to offer in 2013 – primarily because we have a lot of overlap between products and product lines.  We’re not a vertical company in that regard.  I suppose one could say our product offerings are more circular in that many do not fall into a single distinct category.  I am a very visual person, and for me, a Venn diagram and our overall “product scale” really helped to understand and clarify our products:

Venn Diagram of Pickering Laboratories
Venn Diagram of Pickering Laboratories
General "Product Scale" for Pickering Offerings
General “Product Scale” for Pickering Offerings
For those of who like lists, you can find one Here, on Pickering’s website, and on LCTech’s Website

For any Questions, please feel free to contact us:

Pickering Laboratories, Inc.
Mountain View, California
Email: sales@pickeringlabs.com
Phone: (direct) 650-694-6700 or (toll-free) 800-654-3330

 

Image of Acai Berries:  http://acaiberryeducation.com/

Chromatography Quiz No. 13

Chromatography Quiz #12 Results

We would like to congratulate our grand prize winners of our last newsletter’s Amino Acid Analysis Chromatography Quiz: Luiz Paulo Mousinho from Chemetric in Brazil, Helene Lachance from Shur-Gain Nutreco in Canada, and Narjes Ghafoori from the LA County Environmental Toxicology Laboratory!!!

They have each won and will be receiving: a $100 gift card from Amazon.com!  We would like to thank all of you for your submissions.

The correct answer for the modified Amino Acids chromatogram: the back pressure regulator on the outlet of the detector stopped functioning properly.  This was indeed another hardware troubleshooting quiz!  The pattern of noise seen in the customer’s baseline is characteristic to this problem, and a new back pressure regulator eliminated the noise.

Thank you!
Pickering Labs

Chromatography Quiz #13:
Identify the error made when running the Carbamate chromatogram below and win a prize!  Simply email your answer as well as your full contact information to Rebecca at rlsmith@pickeringlabs.com by August 30, 2013 in order to win.  You will receive email confirmation that your submission has been received.  The troubleshooting answer and winner congratulations will be published in the next issue (to be anonymous, please notify Rebecca in submission).

Carbamate Analysis for US EPA Method 531.1

Pickering Standard: 1700-0063 Carbamate Test Mixture, 2.5 µg/mL, 10 µL injection

Pickering Column: 1846250 Carbamate Column, C18, 4.6 x 250 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:

TIME

WATER

MeOH %

0

85

15

1

85

15

44

25

75

44.1

0

100

49

0

100

49.1

85

15

57

85

15

 

Post-column conditions:

Reagent 1: Hydrolysis reagent CB130

Reagent 2: 100 mg of OPA, 2 g Thiofluor™ in 950 mL of CB910

Reactor 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

Troubleshooting Chromatogram:

Troubleshooting chromatogram_CarbamateReference Chromatogram:

Reference chromatogram_Carbamate

Pickering Exhibits at Pittcon 2013

This year’s Pittcon was held in Philadelphia, Pennsylvania from March 17-21, 2013.

view of philly from the museum On display were Pinnacle PCX, EluVAC, and a video of the FREESTYLE Automated Sample Preparation Instrument.  The video was a new technique for us, and it was well received.

The video in our booth was a combination of the separate videos for each module of the FREESTYLE Automated Sample Preparation Instrument. You can view the originals here (they are very informative, and we highly recommend them): FREESTYLE VIDEOS

Wendy, Mike and David enjoyed visiting with existing and future customers, as well as our distributors from around the world, including our Canadian distributor, Chromatographic Specialties.

Before the show opened, we had the opportunity to explore the city.  Philadelphia is one of our oldest cities and is full of history and landmarks. Some of this editor’s favorites include Independence Hall and the surrounding neighborhoods, and the Art Museum (see more below).  On this trip, we explored Reading Terminal Market, and sampled that famous cuisine, the Philly Cheese steak Sandwich. I’m told it is not truly a Philly Steak sandwich unless you have it with Cheez Whiz. Any type of real cheese doesn’t count. I made that mistake on my first trip to Philadelphia, and the man behind the counter let me know it!  I wasn’t about to make that mistake again:

philly cheesesteak

The Philadelphia Museum of Art is known for its amazing collection of artwork (viewed on a previous visit), but is also made famous by the scene of Sylvester Stallone running up the stairs in the movie Rocky.  Since the author of this entry happened to be training for a race, she decided that a little cold wasn’t going to stop her. So she put on her iPod (Rocky Theme playing, of course), and ran from the hotel to the top of the steps and back (total distance: about 2.8miles).

view from the bottom

wendy philly top of steps

wendy rockyOn the return to the hotel, I came across a version of the LOVE sculpture, by American Artist Robert Indiana. I always thought it was was much bigger…

love sculpture

 

For those of you interested in learning more about the sculpture, click HERE

If you’re ever in Philadelphia, the Philadelphia Museum of Art is definitely worth a visit.

But if you can’t make the trip to Philadelphia, you could also stay home and watch Rocky…

Aflatoxins in Edible Oils Collaborative Study Published

Pickering Laboratories, Inc was one of several laboratories who participated in a collaborative study, the results of which were published in the November-December issue of Journal Of AOAC International.

Here is the reference:

Determination of Aflatoxins B1, B2, G1, and G2 in Olive Oil, Peanut Oil, and Sesame Oil using Immunoaffinity Column Cleanup, Post Column Derivatization and Liquid Chromatography/Fluorescence Detection: Collaborative Study.

Authors: Bao, Lei; Liang, Chengzhu; Trucksess, Mary W.; Xu, Yanli; Lv, Ning; Wu, Zhenxing; Jing, Ping; Fry, Fred S.

Source: Journal of AOAC International, Volume 95, Number 6, November-December 2012, pp. 1689-1700(12)

Participating laboratories could use Photochemical Derivatization or electrochemical derivatization.  The sample clean-up was performed using Immunoaffinity clean-up columns.

Pickering has many great tools for the analysis of Aflatoxins, including the UVE Photochemical Reactor, our Pinnacle PCX, immunoaffinity clean-up columns, HPLC columns, and column handling equipment such as the FREESTYLE SPE, AcceCLEAN, and EluVac.