Method Description

Adulterants Survey:

All results are measured using spectrophotometry at wavelengths specified by the reagent manufacturer. The use of a refractometer may also be used in the specific gravity measurement.(Package inserts: Specimen Validity Test Creatinine. Roche Diagnostics; V3.0, 08/2015; Specimen Validity Test Nitrite. Roche Diagnostics; V3.0, 08/2018, Specimen Validity Test Oxidant. Roche Diagnostics; V 3.0, 08/2018; Specimen Validity Test pH Roche Diagnostics; V3.0, 02/2019, Specimen Validity Test Specific Gravity. Roche Diagnostics; V4.0, 08/2022)

Pain Clinic Survey 10:

The amphetamines, barbiturates, benzodiazepines, cocaine, methadone metabolite, opiates, phencyclidine, and tetrahydrocannabinol metabolite assays are based on the kinetic interaction of microparticles in a solution as measured by changes in light transmission. In the absence of sample drug, soluble drug conjugates bind to antibody-bound microparticles causing the formation of particle aggregates. As the aggregation reaction proceeds in the absence of sample drug, the absorbance increases. When a urine sample contains the drug in question, this drug competes with the drug derivative conjugate for microparticle-bound antibody. Antibody bound to sample drug is no longer available to promote particle aggregation, and subsequent particle lattice formation is inhibited. The presence of sample drug diminishes the increasing absorbance in proportion to the concentration of drug in the sample. Sample drug content is determined relative to the value obtained for a known cutoff concentration of drug.(Package inserts: AMPS2. Roche Diagnostics; V 10.0, 09/2018; BARB. Roche Diagnostics; V 13.0, 09/2021; THC2. Roche Diagnostics; V 13.0, 03/2022; BNZ2. Roche Diagnostics; V 2.0, 04/2024; COC2. Roche Diagnostics; V 9.0, 03/2019; OPI2. Roche Diagnostics; V 16.0, 01/2022; PCP. Roche Diagnostics; V 13.0, 09/2021; EDDP Specific Urine Enzyme Immunoassay, Immunalysis Corp; 09/2018)

Oxycodone Screen:

Oxycodone and its metabolite, oxymorphone, are analyzed via immunoassay. The assay uses specific antibodies that can detect oxycodone and oxymorphone without any significant cross-reactivity to other opiate compounds. The assay is based on the competition between a drug labeled with glucose-6-phosphate dehydrogenase (G6PD) and free drug from the urine sample for a fixed amount of specific antibody binding sites. In the absence of free drug from the sample, the specific antibody binds the drug labeled with G6PD and causes a decrease in enzyme activity. This phenomenon creates a direct relationship between the drug concentration in urine and enzyme activity. The enzyme activity is determined spectrophotometrically at 340 nm by measuring the conversion of nicotinamide adenine dinucleotide (NAD) to NADH.(Package insert: OXY. Roche Diagnostics; V3.0, 08/2023)