Stability of drugs of abuse in urine samples stored at -20 degrees C.
J Anal Toxicol
; 18(7): 391-6, 1994.
Article
en En
| MEDLINE
| ID: mdl-7861752
Isolated studies of the stability of individual drugs of abuse have been reported. However, few have evaluated stability in frozen urine samples stored for 12 months. We have determined the stability of 11-nor-9-carboxy-delta 9-tetrahydrocannabinol (9-COOH-THC), amphetamine, methamphetamine, morphine, codeine, cocaine, benzoylecgonine, and phencyclidine in 236 physiological urine samples. Following the initial quantitative analysis, the samples were stored at -20 degrees C for 12 months and then reanalyzed. All drug concentrations were determined by gas chromatographic-mass spectrometric methods with cutoff concentrations of 5 ng/mL for 9-COOH-THC and phencyclidine and 100 ng/mL for each of the other drugs. The average change in the concentrations of these drugs following this long-term storage was not extensive except for an average change of -37% in cocaine concentrations.
Buscar en Google
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Drogas Ilícitas
/
Criopreservación
Límite:
Humans
Idioma:
En
Revista:
J Anal Toxicol
Año:
1994
Tipo del documento:
Article
Pais de publicación:
Reino Unido