Caprylic acid-induced impurity precipitation from protein A capture column elution pool to enable a two-chromatography-step process for monoclonal antibody purification.

This article presents the use of caprylic acid (CA) to precipitate impurities from the protein A capture column elution pool for the purification of monoclonal antibodies (mAbs) with the objective of developing a two chromatography step antibody purification process. A CA-induced impurity precipitation in the protein A column elution pool was evaluated as an alternative method to polishing chromatography techniques for use in the purification of mAbs. Parameters including pH, CA concentrations, mixing time, mAb concentrations, buffer systems, and incubation temperatures were evaluated on their impacts on the impurity removal, high-molecular weight (HMW) formation and precipitation step yield.

Investigation of nitrite adulteration on the immunoassay and GC-MS analysis of cannabinoids in urine specimens.

Nitrite ion has been identified as the active ingredient of two commercial adulterants that could cause discrepant results between the immunoassay screening and gas chromatographic-mass spectrometric (GC-MS) confirmation of 11-nor-delta9-tetrahydrocannabinol-9-carboxylic acid (THCCOOH) in urine. Procedures to chemically convert the nitrite ion at the beginning of sample preparation for GC-MS analysis may not overcome all nitrite adulteration cases because portions of the THCCOOH might have been lost between the time of sample collection and the time of analysis. This study was conducted to further investigate the influence of both urine sample matrix and the duration of nitrite exposure on nitrite interference of THCCOOH detection.

Determination of five abused drugs in nitrite-adulterated urine by immunoassays and gas chromatography-mass spectrometry.

The adulteration of urine specimens with nitrite ion hasseen shown to mask the gas chromatography-mass spectrometry (GC-MS) confirmation testing of marijuana use. This study was designed to further investigate the effect of nitrite adulteration on the detection of five commonly abused drugs by immunoassay screening and GC-MS analysis. The drugs tested are cocaine metabolite (benzoylecgonine), morphine, 11-nor-delta-tetrahydrocannabinol-9-carboxylic acid (THCCOOH), amphetamine, and phencyclidine.

ONTRAK TESTCUP: a novel, on-site, multi-analyte screen for the detection of abused drugs.

We developed a rapid, sensitive, and simple-to-use multi-analyte diagnostic device for the detection of drugs of abuse in urine: the ONTRAK TESTCUP. No sample or reagent handling is necessary with this device, and the device also serves as the sample collection cup. The TESTCUP contains immunochromatographic reagents that qualitatively and simultaneously detect the presence of benzoylecgonine, morphine, and cannabinoids (delta9-tetrahydrocannabinol [THC] in urine.