Determination of capsaicin, dihydrocapsaicin, and nonivamide in self-defense weapons by liquid chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry.

Sensitive and selective liquid chromatography-mass spectrometry (LC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS-MS) methods for the analysis of capsaicin, dihydrocapsaicin, and nonivamide in pepper spray products have been developed. Chromatographic separation of the capsaicinoid analogues was achieved using a reversed-phase HPLC column and a stepwise gradient of methanol and distilled water containing 0.1% (v/v) formic acid. Identification and quantification of the capsaicinoids was achieved by electrospray ionization single-stage mass spectrometry monitoring the protonated molecules of the internal standard (m/z 280), capsaicin (m/z 306), dihydrocapsaicin (m/z 308), and nonivamide (m/z 294) or by tandem mass spectrometry monitoring the appropriate precursor-to-product-ion transitions. The plot of concentration versus peak area ratio was linear over the range of 10-750 ng/ml using LC-MS and 10-500 ng/ml using LC-MS-MS. However, to accurately quantify the capsaicinoids in the pepper spray products calibration curves between 10 and 1000 ng were constructed and fit using a weighted quadratic equation. Using the quadratic curve, the accuracy of the assay ranged from 91 to 102% for all analytes. The intra-assay precision (RSD) for capsaicin was 2% at 25 ng/ml, 10% at 500 ng/ml, and 3% at 800 ng/ml. The inter-assay precision (RSD) for capsaicin was 6% at 25 ng/ml, 6% at 500 ng/ml, and 9% at 800 ng/ml. Similar values for inter- and intra-assay precision were experimentally obtained for both dihydrocapsaicin and nonivamide. The analysis of selected pepper spray products demonstrated that the capsaicinoid concentration in the products ranged from 0.7 to 40.5 microg/microl.

The effects of collection methods on oral fluid codeine concentrations.

The use of a variety of alternative biological specimens such as oral fluid for the detection and quantitation of drugs has recently been the focus of considerable scientific research and evaluation. A disadvantage of drug testing using alternative specimens is the lack of scientific literature describing the collection and analyses of these specimens and the limited literature about the pharmacokinetics and disposition of drugs in the specimen. Common methods of oral fluid collection are spitting, draining, suction, and collection on various types of absorbent swabs. The effect(s) of collection techniques on the resultant oral fluid drug concentration has not been thoroughly evaluated. Reported is a controlled clinical study (using codeine) that was designed to determine the effects of five collection techniques and devices on oral fluid codeine concentrations. The collection techniques were control (spitting), acidic stimulation, nonacidic stimulation, and use of either the Salivette or the Finger Collector (containing Accu-Sorb) oral fluid collection devices. Preliminary data were collected from two subjects using the Orasure device. The in vitro drug recovery was also evaluated for the Salivette and the Finger Collector devices. With the exception of a single time point, codeine concentrations in specimens collected by the control method (spitting) were consistently higher than concentrations in specimens collected by the other methods. The control collection concentrations averaged 3.6 times higher than concentrations in specimens collected by acidic stimulation and 1.3 to 2.0 higher than concentrations in specimens collected by nonacidic stimulation or collection using either the Salivette or the Finger Collector devices. When calculated using oral fluid codeine concentrations from the clinical study, the elimination rate constant, t(1/2), AUC and the peak oral fluid concentrations demonstrated device differences. The slope of the elimination curve for codeine using the acidic collection method exceeded that of the other four methods. As a result, the t(1/2) for the acidic method was significantly less than that of the control method (1.8 vs. 3.0 h, respectively). Oral contamination contributed to the control method having higher AUC than that calculated using the other methods. There was considerable variation in peak codeine concentrations between devices and between individuals within each collection method. When samples were collected simultaneously with the Salivette and the Finger Collector, the mean codeine concentrations were similar. We were able to recover > or = 500 microL of oral fluid from 81.8% of the clinical samples collected with the Salivette. However, we were able to recover this volume from only 25.5% of the samples collected with the Finger Collector. In addition, the in vitro drug recoveries were lower using the Finger Collector. When oral fluid was collected nearly simultaneously by the control method and by use of the Salivette, mean control codeine concentrations were 2.3 times higher, but the duration of detection was similar for both methods.

Validation of twelve chemical spot tests for the detection of drugs of abuse.

Validation procedures are described for 12 chemical spot tests including cobalt thiocyanate, Dille-Koppanyi, Duquenois-Levine, Mandelin, Marquis, nitric acid, para-dimethylaminobenzaldehyde, ferric chloride, Froehde, Mecke, Zwikker and Simon's (nitroprusside). The validation procedures include specificity and limit of detection. Depending on the specificity of each color test, between 28 to 45 drugs or chemicals were tested in triplicate with each of the 12 chemical spot tests. For each chemical test, the final colors resulting from positive reactions with known amounts of analytes were compared to two reference color charts. For the identification of unknown drugs, reference colors from the Inter-Society Color Council and the National Bureau of Standards (ISCC-NBS) and Munsell charts are included along with a description of each final color. These chemical spot tests were found to be very sensitive with limits of detection typically 1 to 50 microg depending on the test and the analyte.

Factors other than iodine deficiency contributing to the endemicity of goitre in Darfur Province (Sudan).

One thousand six hundred and four children in nine schools in five villages of Darfur Province were examined for goitre. The incidence in Kas, Tawaila and Nyala was 75, 55, 13 (girls) 46, 35 and 10 (boys) per cent). Dietary survey showed the proportion of energy derived from millet to be 73.6, 66.7 and 37.1 per cent. Factors contributing to the high incidence of goitre in the province are discussed, and include low iodine intake, high Na, K and Fe in water, low vitamin A in the diet and poor nutritional status. A goitrogenic factor present in millet may account for the differences between villages.