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amino acid, amino acids, Chromatography Quiz

Chromatography Quiz #9

Chromatography Quiz #8 Results
We would like to congratulate the grand prize winners of our last newsletter’s Carbamates Analysis Chromatography Quiz: Mary Benzinger from North Coast Laboratories, and Keena Njoroge and Matthew Hartz from Underwriters Laboratories!!!
They have won, and will shortly be receiving: Wine Hourglasses courtesy of Uncommongoods.com! Additionally, all participants will be receiving a $20 gift card from Jamba Juice!  Again, we would like to thank all of you for your submissions.  

The correct answer for the modified Carbamates chromatogram: the noisy baseline is due to the HPLC pump having excessively large pulsations (or pressure variations).  Post-column systems containing reciprocating pumps can also cause noisy pulsations in the baseline, and the frequency of the sine waves should be evaluated to determine which pump is causing the noise.

This problem is most often caused by one of the following: bad pump seals, bad check valves, scratched or damaged pump pistons, faulty pulse dampener, or problems with connections to the pump. 

This problem can also be caused by dirty reagents or eluents, however in this case the pulsations would be accompanied by the elevation of the background signal. 

We had a lot of excellent responses to this quiz! 

Thank you! 
Pickering Labs

Chromatography Quiz #9:

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.comby May 15th 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 Physiological Fluid

Pickering Standard: 1700-0180 Native Sample Standard, acidics and neutrals, in 0.1 N HCl, 2.5 µmole/mL, 10 µL injection

Pickering Column: 0354100T High Efficiency Lithium Cation-exchange Column, 4.0 x 100 mm

Normal Operating Conditions: (for reference only, condition changes may be reflected in chromatogram)
Column Temperature: 36 °C

Flow rate: 0.35 mL/min

Eluent Gradient:

TIME
Li275 %
Li750 %
RG003 %
0
100
0
0
12
100
0
0
48
65
35
0
90
0
100
0
95
0
100
0
120
0
94
6
122
0
94
6
122.1
100
0
0
140
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
An example of a good chromatogram can be found here: Standard Lithium Chromatogram
AcceCLEAN, aflatoxin, Amino Acid Analysis, amino acids, antioxidants, artificial perspiration, carbamate, clean-up, deoxynivalenol, dietary supplements, elisa, eluvac, ergot alkaloid, freestyle, glyphosate, GPC, immunoaffinity cleanup, Multi-residue Mycotoxin Analysis, mycotoxin, natural toxins, Ninhydrin, ochratoxin, paralytic shellfish toxin, pinnacle pcx, post-column derivatization, psp, syringe pump, Trione, UVE, vomitoxin

Pickering Products

1 Comment

Mycotoxins: Clean-up Columns, ELISA Kits, Post-Column Derivatization Instruments & Methods, SPE manifolds (manual & automated) for the analysis of:

Aflatoxins
Ochratoxin A
DON
Nivalenol
Fumonisin FB1, FB2
Zearalenone
Ergot Alkaloids

Post-Column Derivatization: Pinnacle PCX, Vector PCX, UVE Photochemical Reactor, Columns, Reagents, Eluants for the analysis of:

Antioxidants
Mycotoxins (individual and multi-residue)
Amino Acids
Biogenic Amines
Paralytic Shellfish Toxin
Polyether Antibiotics
Hexavalent Chromium
Vitamins
Sugars
Nitrate/Nitrite
Bromate
Carbamate Pesticides
Glyphosate Herbicide
NDELA
Formaldehyde

Sample Preparation (clean-up) Instruments:

FREESTYLE for SPE, GPC, online-concentration
FREESTYLE ThermELUTE for Aflatoxin analysis (direct inject onto HPLC)
AcceCLEAN for SPE (incl. Immunoaffinity columns)
EluVAC vacuum manifold for SPE (incl. Immunoaffinity columns)
GPC QUATTRO for manual GPC Cleanup
DECS System for the cleanup of samples for Dioxin analysis

Chemistry Products:

Artificial Perspiration
Artificial Saliva
High Purity Water

Stand-Alone OEM Syringe Pump:

For any applications requiring an inert flow path, volumes up to 70mL, and pressures up to 500psi

For More Information visit:

www.pickeringlabs.com

or email: sales@pickeringlabs.com

antioxidants, post-column derivatization

Antioxidants Are No Accident

Recently we learned about a paper published by a team in Poland describing their work on the analysis of anti-oxidants. We wanted to share this work with the AHPA community.
Barbara Kusznierewicz and her colleagues from Gdansk University of Technology have developed a method to analyze antioxidants in complex mixtures by HPLC with post-column derivatization and UV/Vis detection. The authors studied three well-known reagents routinely used in colorimetric assays to measure antioxidant activity. They determined that Diammonium 2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and Folin-Ciocalteu reagent (FCR) were best suited for post-column derivatization of antioxidants after they were separated on reversed-phase HPLC column.
Photo from FoodProductDesign.com

Researches optimized HPLC conditions as well as post-column parameters such as concentration of post-column reagent, duration of derivatization reaction and reaction temperature. Trolox and 20 other phenolic compounds were investigated and scientists were able to demonstrate good correlation between Trolox equivalent antioxidant capacity (TEAC) determined by HPLC with post-column derivatization and standard colorimetic assay. This method was successfully applied to analysis of extracts from sloe fruits and mirabelle plums and allowed to calculate concentration of individual antioxidants as well as TE antioxidant capacity.


Pickering Laboratories strives to provide new post-column applications, and the instruments and chemistry to support these applications. It is our philosophy to provide a complete solution and customer support. We plan to follow-up this interesting research with some development of our own to see if we can optimize the post-column technique further. 
The full version of the paper can be found in the Wiley online library:
REFERENCE:
Kusznierewicz, B., Piasek, A., Bartoszek, A., Namiesnik, J., “The Optimisation of Analytical Parameters for Routine Profiling of Antioxidants in Complex Mixtures by HPLC Coupled Post-column Derivatization,” Phytochemical Analysis, 22, 392-402 (2011)

AOAC, clean-up, freestyle, GPC, lctech, New Products, pickering laboratories, spe

New! FREESTYLE Series Instrumentation

Pickering Laboratories introduced the Freestyle™ Sample Clean-up workstation from LCTech at this year’s AOAC International meeting in New Orleans.  Building on the success of the GPC Ultra product line of Gel Permeation Chromatography systems,  the FREESTYLE™Series  is an innovative design adding new time saving features to the automated sample clean-up work flow.

The Freestyle™ begins with:

  • FREESTYLE™ Basic, which has an XYZ robotic arm for automated liquid handling; dilutions, additions, mixing, extraction, dispensing, and other operations.
  • Add the GPC module for GPC processing of up to 4 GPC columns. 
  • Add to this the SPE module to enable SPE processing. 
  • Add the EVA module for programmable evaporation and solvent exchange for a completely automated in-line evaporation instrument.
Flexibility of the system starts with the suspended rack design. The system can handle multiple vial shapes from 1mL to 1000mL.

The FREESTYLE™software is drag and drop to program multiple sample parameters and able to handle exceptions to insert into the workflow. Graphical reporting and full audit logs round out the robust software.

The FREESTYLE™ automation of sample clean-up saves time, improves consistency and protects your staff from potentially harmful chemical exposure.

Send us an email or give us a call to find out how FREESTYLE™ can solve your sample clean-up challenges. 

Email: sales@pickeringlabs.com
Phone: Toll-free: 800-654-3330, Direct: 650-694-6700

ameritech, bceia, china, shanghai, tegent, tianjin

Pickering Participates in BCEIA 2011 in Beijing, China

By David Mazawa
Beijing, outside of Exhibition Center
The Beijing Conference and Exhibition on Instrumental Analysis was held on October 12-15, 2011 at the Beijing Exhibition Center. This biennial exhibition is sponsored by the China Association for Instrumental Analysis and supported by the Ministry of Science and Technology of China. The BCEIA is 3 days long, because it will take you a full three days to cover all 17,000m² of exhibition space. 

The Beijing Exhibition Center became a bustling city of exhibitors and guests from all over the world showcasing instruments from the fields of Electron Microscopy & Material Sciences, Mass Spectrometry, Optical Spectroscopy, Chromatography, Magnetic Resonance, Electroanalytical Chemistry, Analytical Techniques in Life Science and Environmental Analysis.

BCEIA Exhibition Hall

David and Ameritech in Tianjin City
David and Tegent
I traveled to China to support our distributors that represented Pickering Laboratories at the BCEIA. I gave training to Ameritech in their Tianjin office and to Tegent in their Shanghai office. 
Both distributors have been working with Pickering Laboratories for many years and are completely capable of supporting our post-column instruments and applications. Their hospitality was incredible and I look forward to visiting them again in the near future.

 
Feel free to contact either Ameritech or Tegent for sale inquiries in China.


The Great Wall of China



David Mazawa

Technical Support Chemist
Pickering Laboratories, Inc.
1280 Space Park Way
Mountain View, CA 94043 USA
Phone: 650-694-6700 ext 710
Fax: 650-968-0749
carbamate, Chromatography Quiz, post-column derivatization

Chromatography Quiz

Chromatography Quiz #7 Results
 

We would like to congratulate the grand prize winner of our last newsletter’s Amino Acid Analysis Chromatography Quiz: Jaime Lee Palmer from Underwriters Laboratories!!!

She has won, and will shortly be receiving: a gift card for Barnes and Noble!  Additionally, for this quiz all our participants will each be receiving a Smiley Face Sampler Box courtesy of The Popcorn Factory!  Again, we would like to thank all of you for your submissions. 
 
The correct answer for the modified Amino Acids chromatogram: the Trione reagent is oxidized.  Either the reagent has been improperly stored (not under Nitrogen), or has been in extended contact with air. 

Thank you! 
Pickering Labs

Chromatography Quiz #8:

Identify the error made when running the Carbamates chromatogram below and win a prize!  Simply email your answer as well as your full contact information to Rebecca at rlsmith@pickeringlabs.com by January 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). 

Carbamate Analysis for US EPA Method 531.1

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

Sample: Actual customer’s 531.1 standard at 10ppb

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

Column Temperature: 42 °C

Flow rate: 1 mL/min

Eluant 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

Full Chromatogram:

 





 

 Enlarged View:

 




 
Further Enlarged View:
  

For an example of a Good Carbamate Chromatogram, click here

dietary supplements, herbal products, natural products, supplyside

SupplySide West Expo 2011

By Mike Gottschalk

Laszlo Torma inside the Venetian Hotel & Casino

The Supplyside West Conference is a very important Herbal Supplement Industry event. It provides important educational and networking opportunities to this $29 billion market. Since the FDA set out required current good manufacturing practices (cGMP) in 2007, the Herbal Supplement producers are working to meet the new requirements before the FDA audits. These regulations are intended to insure the quality, purity and safety of the Herbal Supplement products available today.  


The show is held in Las Vegas, Nevada, October 19-23. Pickering Laboratories exhibited at the show. We introduced our instruments, and methods to the industry. Of primary concern are Mycotoxins and Amino Acids, but also pesticides. Our GPC Clean-up and post-column instruments are well-suited to these applications. 

In addition to the literature and instruments in the booth, we presented two posters:

“Immunoaffinity Clean-up and  Analysis of Aflatoxins and Ochratoxin A in Herbs & Spices using HPLC with Post-column Photochemical Derivatization”

The production of herbal supplements and spices is a fast growing industry. There are numerous reports on the presence of Mycotoxins in commercially available herbs and spices such as chamomile, black and white tea leaves, ginkgo leaves, paprika and cumin. We developed a simple, sensitive and robust HPLC-Post Column Derivatization method for analyzing Aflatoxins B1, B2, G1, G2 and Ochratoxin A in herbs and spices. AflaOTAClean Immunoaffinity columns contain antibodies specific for both classes of Mycotoxins and allow for fast and efficient sample clean-up. We used the AcceClean automated workstation, which processes three samples simultaneously.


“Accelerated Amino Acids using HPLC with Post-Column Derivatization”

We developed an accelerated amino acids analysis method for Physiological and Protein Hydrolysate samples that utilizes temperature and eluant gradients. Protein Hydrolysates can be analyzed in 48min (inject-to-inject). Amino Acid Analysis is an important step in the Quality Control and R&D of dietary supplements, sports drinks, pharmaceuticals and in any type of sample where the amino acid content is of importance. The objective of the study was to reduce the total run time of Amino Acid Analysis by implementing both a column temperature gradient and a linear buffer gradient using HPLC with Post-column derivatization.
If you would like a copy of either or both of these posters or any additional information  about our products, please feel free to send us an email or give us a call:

Phone: Toll-free: 800-654-3330 Direct: 650-694-6700

Dinner on the canal in “Venice”