Chromatography Quiz No. 5 and Results from Quiz 4

Chromatography Quiz #4 Results
Congratulations to the grand prize winner of our last newsletter’s Amino Acid Chromatography Quiz: Matthew Hartz from Underwriters Laboratories!

He has won, and will shortly be receiving, a $150 gift card to Dick’s Sporting Goods! Additionally, for this quiz our other participants will each be receiving a $20 gift card from Amazon.com. Thank you all for your submissions!

The correct answer for the modified Amino Acid chromatogram: the guard column has been contaminated with proteins. The dirty guard causes poor peak shape and loss of resolution on key pairs of amino acids. Replacing the guard will restore the chromatography.

Thank you!
Pickering Labs

Chromatography Quiz #5:

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 December 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).

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

For an example of a Good Carbamate Chromatogram, Click Here