Detection of Cocaine in Seized Drug Samples by Capillary Electrophoresis Tandem Mass Spectrometry
A methodology using capillary electrophoresis with tandem mass spectrometry detection (CE-MS/MS) was developed, and applied to determine the cocaine content of seized drugs. The cocaine separation among other concomitants by capillary electrophoresis was achieved in just 4.0 minutes using 30 mM ammonium formate, pH 6.5, as a background electrolyte (BGE). The correlation coefficient of the calibration curve in the range of 0.02 to 1 μg/mL was upper 0.999, and the limits of detection (LOD) and limits of quantification (LOQ) were 0.003 μg/mL and 0.01 μg/mL, respectively. The relative standard deviation repeatability (intraday and interday) was less than 6.5% (peak area). The analysis of seized suspected illegal drugs revealed the presence of cocaine in 93% of samples (n = 11), in amounts ranging from 0.04 to 429 mg/g, showing a high variability of concentrations of cocaine. The user can change the provider and, due to the large variability of concentration, be lead to an accidental overdose.
Quality of cocaine seized in 1997 in the street-drug market of São Paulo city, Brazil
Teores de cocaina e adulterantes bem como varios diluentes foram determinados em 389 amostras de po branco apreendidas na cidade de Sao Paulo, no ano de 1997. Cocaina e seus adulterantes foram analisados por cromatografia em camada delgada, cromatografia em fase gasosa (detetor de ionizacao de chama) e cromatografia em fase gasosa acoplado a espectrometria de massa (CG/MS). Diluentes foram analisados atraves de "spot tests" e da cromatografia em camada delgada. Foram obtidos os seguintes resultados: em 4,4% das amostras nao foram detectados cocaina e adulterantes; de todas as amostras positivas para cocaina, 14% nao continham mais que 200 mg/g de po; em 70% a pureza da cocaina variou de 201 a 550 mg/g e em 16% nao foi maior que 700 mg/g. Os anestesicos locais lidocaina e procaina foram detectados em 19 amostras em concentracoes que variaram de 10 a 602 mg/g de po. Cafeina foi encontrada em duas amostras. Os principais diluentes detectados foram: carbonatos e bicarbonatos, silicatos, acucares, amido, borato e sulfatos. Contaminantes (produtos secundarios) originarios do refino da pasta de coca ou de processos de decomposicao nao foram analisados.
Investigations on the rôle of organic matter in plant nutrition
1. As the result of decomposition of green manure in a swamp soil, the coarse fractions (including coarse and fine sand) of the surface layer (first 3 inches) decreased by 11·2 per cent. while the fine ones (silt+clay) increased by 9·8 per cent. in the course of 43 days. The effect was less pronounced in the manured soil maintained at 60 per cent. saturation, while no alteration was to be noticed in the case of the unmanured specimens. 2. Treatment with dilute hydrochloric acid prior to dispersion had no appreciable effect on the estimates of mechanical composition obtained in the different cases. Loss in solution was also comparatively small. 3. The silica-sesquioxide ratio increased slightly as the result of decomposition of green manure in swamp soil. The composition of the fine fractions was also altered, the total percentages of the oxides of iron, aluminium and silicon increasing from 90·5 to 99·3 in the course of 71 days. 4. The practical significance of the above and related observations has been discussed.