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Biomedical subjects

B S Finkle

Publications and source records attributed to B S Finkle.

47 records · Page 3Linked to original sources
PubMedDate not supplied

Gas chromatography-chemical ionization mass spectrometry of cocaine and its metabolites in biological fluids.

A gas chromatographic-chemical ionization mass spectrometric (GC-CIMS) method is described for the determination of cocaine, benzoylecgonine, and norcocaine. The procedure uses stable isotopes as internal standards and a mixture of methane-ammonia as chemical ionization reagent gas. Run-to-run and within-run coefficients of variation (%) are less than 10% and the method has a sensitivity of less than 5 ng/mL from 1 mL or 1 gram of sample. The procedure has been applied to a number of cases involving cocaine intoxication and analytical data from these are described.

Body Fluids↗
PubMedDate not supplied

Determination of methaqualone and its major metabolite in plasma and saliva after single oral doses.

A gas liquid chromatographic procedure for the determination of methaqualone and metabolite l (2-methyl-3(2-hydroxymethylphenyl)-4-(4H)-quinazoline) in plasma and saliva is described. The method requires 1.0 mL of sample and involves internal standard addition, extraction with butyl chloride, chromatography on a 1% SP-1,000 column packing using nitrogen phosphorous detectors. Within-run and day-to-day coefficient variations were less than 8% and the procedure has a sensitivity limit of 20 ng/mL. The method has been used to monitor both parent drug and metabolite in plasma and samples collected after a single oral dose.

Chromatography, Gas↗
PubMedDate not supplied

Plasma and urine disposition of 1-alpha-acetylmethadol and its principal metabolites in man.

The disposition of 1-alpha-acetylmethadol (LAAM) in plasma and urine was monitored by GC/CIMS following oral administration of 10 doses (0.73-1.5 mg/kg) over 42 days, to twelve human subjects. Plasma concentration-time course profiles fitted a two-compartment, first order kinetic model. Mean plasma t1/2 alpha for LAAM was 2.4 hours; t1/2 beta was 37.5 hours for the first dose and 46.8 hours for the last dose. The mean terminal half-life for nor-LAAM was 38.2 hours for first and 64.6 for last dose; for dinor-LAAM t1/2 beta was 168 hours, last dose. Drug accumulation occurred in some subjects, but within the study range, dosage was not related to maximum plasma levels nor to accumulation. In urine, the sum of LAAM, nor-LAAM, and dinor-LAAM represented 25% of the dose, and unconjugated methadol metabolites, 1.6-1.7%.

Adult↗
PubMedDate not supplied

Progress in forensic toxicology: beyond analytical chemistry.

The dominant role of analytical chemistry in applied forensic toxicology is described briefly from an historical perspective. It is argued, however, that obligations imposed on forensic toxicologists by the law, medicine, and society for understanding toxicity in an increasing variety of case problems is really the major challenge and obligation facing toxicologists today. Case examples and rationale are presented in support of this argument. Needs and possible solutions to redress the current professional imbalance are suggested; such as a program to monitor prospectively adverse drug actions and interactions, forensic toxicology reference centers, graduate training programs, and collaborative research involving analytical toxicologists and biomedical researchers, including pathologists. There is a need to develop an industrial, governmental, and professional partnership. These proposals are discussed and justified.

Chemistry Techniques, Analytical↗
PubMedDate not supplied

An HPLC method for the quantitation of quinidine and its metabolites in plasma: an application to a quinidine-phenytoin drug interaction study.

A rapid and simple method is described for the separation of quinidine (Q), its metabolites 3-hydroxyquinidine (30HQ) and 2'oxoquinidinone (QD) as well as the quinidine salt contaminant, dihydroquinidine (DHQ) in plasma by high pressure liquid chromatography (HPLC). A silica column was used with methanol: 1 N ammonium nitrate: 2 N ammonium hydroxide (28:1:1 v/v) as the mobile phase to separate the compounds and a fluorescence spectrophotometer for detection. Application of this method is demonstrated by the analysis of human plasma samples collected from a volunteer during a phenytoin-quinidine drug interaction study.

Chromatography, High Pressure Liquid↗
PubMedDate not supplied

Quantitative analysis of emetine and cephaeline by reversed-phase high performance liquid chromatography with fluorescence detection.

A versatile method for the quantitation of emetine and cephaeline in biological samples is described. Two milliliters of samples containing N-propylprocainamide as the internal standard are buffered to pH 9 and extracted with n-butyl chloride. After subsequent back extraction into 0.01 M hydrochloric acid, a portion of the acid layer is analyzed by reversed-phase high performance liquid chromatography with fluorescence detection. Routinely, the minimum level of detection for both drugs is 5 ng/mL and linearity is demonstrated from 5 to 2500 ng/mL.

Body Fluids↗
PubMedDate not supplied

Drugs in fatally injured young male drivers.

One or more drugs were detected in 81 percent of 440 male drivers, aged 15-34, killed in motor vehicle crashes in California; two or more drugs were detected in 43 percent. Alcohol, the most frequently found drug, was detected in 70 percent of the drivers, marijuana in 37 percent, and cocaine in 11 percent. Each of 24 other drugs was detected in fewer than 5 percent. Except for alcohol, drugs were infrequently found alone; typically, they were found in combination with high blood alcohol concentrations. The causal role of drugs in crashes was assessed by comparing drivers with and without drugs in terms of their responsibility for the crash. Alcohol was associated with increased crash responsibility; the role of other drugs could not be adequately determined.

Accidents, Traffic↗