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aflatoxin, AOAC

Southern Section AOAC Meeting

By Wendy Rasmussen

From April 11-12, Pickering attended the Southern Section AOAC Meeting in Atlanta, Georgia. 

The meeting was well attended, and we enjoyed some good talks with current and future customers as well as long-time friends in the industry. 


In preparation for our Vendor Seminar (see below), I did some research about the southern states, and Georgia in particular. In the process, I learned a couple of interesting facts about Georgia.  For example, even though Georgia is nicknamed the Peach State, they’re only the 3rd largest producer of peaches. Turns out the state is known for its Quality rather than the quantity of the fruit. According to the internet, Georgia produces A LOT of poultry & eggs (Georgia is ranked 1st in the US for production of broilers*),  but also peanuts as well as cotton and tobacco.

We presented a Vendor Seminar at the meeting about our Aflatoxin Analysis products. We opted for a “show & tell” approach in which we brought in the key components to the method: 

UVE Photochemical Reactor

 

AflaClean Immunoaffinity Columns


and the AcceCLEAN Automated Sample Handling Workstation

The combination of these products was later demonstrated at the Mid West AOAC Workshop in Lincoln, NE



More about Georgia:
http://georgiainfo.galileo.usg.edu/gaecon.htm
http://en.wikipedia.org/wiki/Georgia_%28U.S._state%29


*Broiler: A young chicken bred for meat
chromatographic specialties, wctow

Western Canada Trace Organic Workshop

By Wendy Rasmussen

Held in Edmonton, Alberta, from May 9-11. Rebecca Smith and I attended the 46th Annual WCTOW. The meeting is a place where scientists can meet and present their work, and to learn about new challenges, applications, and methods.

We have attended this workshop in the last couple of years so that we could support our distributor in Canada, Chromatographic Specialties, but also to meet and get to know our current and future customers in western Canada. 

Some highlights included the measurement of antibiotics excreted by cattle and how antibiotics in manure spread on the ground as fertilizer can ultimately run off into the drinking water. Another interesting topic, especially for Alberta, is the question of identification of napthenic acids in water and soil to determine whether is naturally occurring or whether it is due to environmental contamination by oil refineries.

After the meeting, we had to good fortune to visit a few laboratories in Edmonton and Calgary.
Amino Acid Analysis, Chromatography Quiz

Chromatography Quiz No. 7

Chromatography Quiz #6 Results
We would like to congratulate the grand prize winners of our last newsletter’s Aflatoxins Analysis Chromatography Quiz: Matthew Hartz and Keena Njoroge from Underwriters Laboratories, Steven Moser from the Oklahoma Dept of Agriculture, Food & Forestry, and Holger Franz from Dionex Germany! 
They have won, and will shortly be receiving: a gift basket stuffed with Starbucks coffee, tea, and treats!  Additionally, for this quiz all of our participants will each be receiving a $20 gift card from Starbucks! Again, we would like to thank you all for your submissions.  
The correct answer for the modified Aflatoxins chromatogram: The Aflatoxins G1 and B1 must be derivatized in order to achieve maximum sensitivity.  The derivatization is achieved either by reaction with Iodine, or with a photochemical reactor.  In this case, we achieved the modified chromatogram by turning off the UVE prior to injection.  The same chromatogram would be noticed if the Iodine reagent was not pumping.  
Thank you! 
Pickering Labs
Chromatography Quiz #7:
Identify the error made when running the Amino Acids 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 31st 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).  
Amino Acid Analysis of Protein Hydrolysate  
Pickering Standard: 012506H, 10 μL injected of 0.25 μmole/mL standard in both chromatograms
Pickering Analytical Column: 1154150 High-Efficiency Sodium Cation-Exchange Column (4.0 x 150 mm)
Pickering GARDTM Column Protection System: 1700-3102
Normal Operating Conditions: (for reference only, condition changes may be reflected in chromatogram)
Column Temperature: 48 °C
Flow rate: 0.40 mL/min
Eluent Gradient:
TIME
1700-0112 %
Na740 %
RG011 %
0
100
0
0
12
100
0
0
34
0
100
0
53
0
100
0
53.1
0
0
100
55
0
0
100
55.1
100
0
0
67
100
0
0
Post-column conditions for amino acid analysis:
Reagent 1: Trione
Reactor 1: 130 °C, 0.5 mL
Reagent flow rate: 0.3 mL/min
Detection: UV-Vis Detector, 570 nm for primary amino acids, 440 nm for secondary amino acids
Amino Acids Chromatogram to Troubleshoot:
Amino Acids Reference Chromatogram:


aflatoxin, Chromatography Quiz

Chromatography Quiz No. 6

Chromatography Quiz #5 Results
We would like to congratulate the grand prize winner of our last newsletter’s Carbamate Chromatography Quiz: June Black from the Pennsylvania Department of Environmental Protection! 
She has won, and will shortly be receiving, an extensive California Wines Gift Basket!  Additionally, for this quiz all of our participants will each be receiving a $25 gift card from Bevmo! Again, we would like to thank you all for your submissions.  
The correct answer for the modified Carbamate chromatogram: The system was improperly equilibrated at a higher percentage of methanol (50:50 Water:Methanol) prior to injection.  After injection, the gradient program began with normal starting conditions (85:15 Water:Methanol). For the less retained compounds, the improper conditions on the column at the time of injection will push them through faster, causing coelutions.  Longer retained compounds are less affected by starting conditions of the column, and impacted more by the gradient (which was correct) so you see less of an effect on the later part of the chromatogram. 
Thank you! 
Pickering Labs
Chromatography Quiz #6:
Identify the error made when running the Aflatoxins chromatogram below and win a prize!  Simply email your answer as well as your full contact information to Rebecca at rlsmith@pickeringlabs.com by March 31st 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). 

Aflatoxins Analysis by AOAC Official Method 2005.08
LCTech Standard: 0.25 ng B2, G2 and 1.0 ng B1, G1 injected on-column in both chromatograms
LCTech Analytical Column: 150 x 4.6 mm; RP C18 (P/N 10522)
LCTech Guard Column: 8 x 4 mm (P/N 10523; holder P/N 10750)
Normal Operating Conditions: (for reference only, condition changes may be reflected in chromatogram)
Column Temperature: 36 °C
Mobile Phase: Water/methanol/acetonitrile 55/30/15
Isocratic Flow rate: 1.3 mL/min
Post-column conditions:
Photochemical Derivatization: 254nm UV low pressure lamp (LCTech UVE derivatizer, Pickering P/N 1100-3347)
Detection: Fluorometer:  ex 365 nm, em 460 nm

maintenance, parts, pinnacle pcx

Pinnacle Preventative Maintenance

Keep your Pinnacle in good condition and minimize downtime by performing annual maintenance. Performing Preventative Maintenance on your Pinnacle PCX is easy to accomplish with the Kits and Instruction we provide. Refer to the Maintenance Section of the Pinnacle Manual for details on performing the maintenance. Contact Pickering Laboratories Technical Support with any questions. 800-654-3330, 650-694-6700, or email support@pickeringlabs.com
Below you can find a general maintenance schedule. Your maintenance schedule will depend on usage. If you use the Pinnacle PCX 24×7, you may want to perform the Preventative Maintenance more often.

Maintenance Schedule

Routine Maintenance

–         Check for leaks every day
–         Replace Flush and Piston Wash reservoirs every week
–         Record operating pressures in a daily log book

Preventative Maintenance

–         Replace Valve and Pump Seals every 12 months
–         Replace the 10um Reagent Frits every 3 months
–         Change the tubing every 24 months

Part Numbers

1000-1003               Kit, PM Service, Pinnacle Single Pump (Pump seals, Valve seals, and replacement filter)
1000-1004               Kit, PM Service, Pinnacle Dual Pump (Pump seals, Valve seals, and replacement filter)
1100-0500               Tubing Kit, Pinnacle Dual Pump
1100-0501               Tubing Kit, Pinnacle Single Pump
1452-0122               Pump Seal Kit, Pinnacle
1452-0200               Valve Seal Tool, Pinnacle (Tool only)
1452-0201               Valve Seals kit, Pinnacle (Seals only)
1452-0202               Valve Maintenance Kit, Pinnacle (seals and tool)
3102-9040               Replacement Reagent 10um Filter
1452-0200               Valve Seal Tool

Parts Lookup

Please try our Parts Lookup on our website if you ever need to find a part number. The Parts Lookup is located on our website. Start at http://www.pickeringlabs.com/
Select Parts Lookup under the Service & Support menu
Or, you can also find the Parts Lookup under the Products menu.
Select the Parts Lookup from the Replacement Components menu on the left side of the page.
Next, choose which instrument you are using.
Once you are in the Parts Lookup, simply click on a part or drag you mouse over the part of interest to see the part numbers.

Sincerely,
David Mazawa
 
Technical Support Chemist
Pickering Laboratories, Inc.
1280 Space Park Way
Mountain View, California 94043 USA
Phone: 650-694-6700, ext. 710
Fax: 650-968-0749
echinacea, herbal products, Michael Pickering

Herbal Remedy

By Michael Pickering
Echinacea purpurea, often called a coneflower, has long been used to ameliorate the symptoms of upper respiratory problems caused by viruses and allergies.  The most common form available in the San Francisco Bay Area is in a tablet called Airborne®.  My wife and daughters always have it on hand.  However, if I ingest a tablet, it worsens my symptoms.  I reasoned that the effect was due to the residual incorporated plant material aggravating my hay fever.  So I decided to test the theory by making a tincture wherein the plant material could be categorically removed. 
When water is the extraction solvent, the product is called an infusion and is taken as a hot “tea.”  My solvent of choice for herbaceous tinctures is potable ethanol (190 proof), although as low as 60 proof may be used.  The Everclear® available in California is only 150 proof.  The same brand in Oregon and Nevada is 190 proof, so I had my Oregonian daughter get me some.  That allowed me to filter out the plant residue.  The experiment provided a useable form of Echinacea that is free of allergic side-effects.  My recommended dose is one teaspoon.  I share the extract with my coworkers, friends, and relatives, who all acclaim its efficacy.  One friend actually claims to be allergy-symptom free.
The flower is an annual which my wife and I cultivate in our garden.  Our two plants provide enough cones per season to make 2 liters of solution.  At Pickering Labs, we recently purchased some Echinacea from an herbal supply vendor as a sample for a multi-mycotoxin study, and rather than cones it was supplied as the plant root, called Black Sampson Root. 
Herbal Tincture Preparation:
–          Put 100 g dried herbs into a sufficiently sized jar.
–          Add 500 mL of 190 proof alcohol.
–          Seal, and place on shaker for three days.
o       Note: Longer contact time is recommended for lower proof alcohol.  Two weeks is recommended for 60 proof, for example.
–          Filter using a 0.45 μm filter.

Echinacea purpurea
Michael Pickering, silk

Silk Stockings

By Michael Pickering
Silk stockings were originally made of a single thread formed into a cylindrical tube.  They were handmade by a process then called tatting and now known as crocheting.  Unlike knitting, which uses two threads and two needles, crocheting only requires one tool, called a hook.  The hook size is scaled to the thread diameter.  In its simplest execution, the process produces a chain-like, continuous series of interlocking loops.  Lace, circular doilies, and rectangular antimacassars were made by creatively interconnecting the chain to form symmetrical patterns.   In the “men’s work – women’s work” divide, tatting fell under the women’s craft and so the products were always useful at home.
Grandma Pickering taught me to tat chains as a preschooler which kept me non-kinetic and silent as I marveled at the ever longer creations while I tried to out-do myself day after day.
 
To make a tube, a mandrill or tool is used with the hook.  The tool consists of a tube with projection pins at one end.  The diameter of the stocking (hose and the frequency of pins controls the symmetry and mesh size.  For each pair of stockings an appropriate length was cut off and knotted to prevent unraveling.  The toe was neatly tied off and a garter, i.e. non-stretchable holder, was sewn or tatted to the top. 
 
By grammar school, I made my own tube tool with a wooden thread spool and headless brads.  I don’t remember the hook, but I suspect it was made from a piece of wire hanger.
The larger ID reactors that Pickering Laboratories offers are made like stockings.  The mandrill has four pins.  The misnomer is that our literature calls them “knitted” because that is the most common description in print and conversation in our industry.  Describing them properly would only create a lot of idle questions.  The necessity for the crocheting is to minimize band spreading.  The post-column reaction occurs after the separation is complete, so when the peaks enter the reactor they are as far apart as they are going to be.  The torturous path eliminates the band spreading of longitudinal mixing by replacing it with radial mixing.

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