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USP <621> Chromatography HPLC PT Express for Liquids


PT Express for laboratories performing testing in accordance with USP <621> using High Pressure Liquid Chromatography HPLC on liquid pharmaceutical materials. read more


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Product Details

Product Details

AVAILABLE DECEMBER 1st 2021!  Qualitative and Quantitative Proficiency Test Express for laboratories performing HPLC Assay of liquid material by USP <621> or equivalent. Participants may report qualitative and/or quantitative results for their liquid material sample(s). Samples provided as a three sample panel. One of three samples will be positive for target analyte. Participants are asked to identify the positive sample by HPLC peak retention time match (ID Test). Determine the concentration (Assay) in milligrams per milliliter (mg/mL) of target analyte in the liquid sample per the USP monograph or equivalent. This product is available year-round as an on-demand proficiency test. It does not need to be ordered during an open PT Study.


Positive Sample: Caffeine Citrate Liquid Solution

Negative Samples: Citric Acid Liquid Solution

Caffeine (powdered solid) Reference Material Standard will be provided with the Proficiency Test Samples

USP PT Schedule

USP PT Schedule

Study Number Study Open Date Study Close Date
PH-0422 4/18/2022


Extended from 6/9/22

PH-0922 9/19/2022 11/18/2022
PH-0123 1/16/2023 3/17/2023
PH-0523 5/15/2023 6/14/2023