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S M Wallace

Publications and source records attributed to S M Wallace.

42 records · Page 3Linked to original sources

Uptake of acetazolamide by human erythrocytes in vitro.

The binding of acetazolamide to human erythrocytes was studied in vitro. Blood and plasma samples were analyzed by electron-capture GLC. At 37 degrees, drug equilibrated between plasma and erythrocytes in approximately 40 min. The effect of plasma concentration on the steady-state level of drug within the erythrocytes was examined. Erythrocyte accumulation of acetazolamide appeared to be a composite of two processes: a nonlinear, saturable process and a linear, diffusion-controlled process. By appropriate linear transformation of the data, estimates of the data, estimates of the erythrocyte binding capacity and the dissociation constant for the drug were obtained.

Acetazolamide↗

The determination of isoniazid and its metabolites acetylisoniazid, monoacetylhydrazine, diacetylhydrazine, isonicotinic acid and isonicotinylglycine in serum and urine.

1. A solvent system was devised for the extraction of isoniazid and its metabolites acetylisoniazid, monoacetylhydrazine, diacetylhydrazine, isonicotinic acid and isonicotinylglycine from serum and urine. 2. Specific chemical and fluorimetric methods were developed for the determination of the extracted isoniazid and acetylisoniazid, and chemical methods for the determination of monoacetylhydrazine, diacetylhydrazine, isonicotinic acid and isonicotinylglycine. 3. When applied to serum, these methods were capable of measuring concentrations of down to about 0.005mug of isoniazid/ml, 0.05mug of acetylisoniazid/ml, 0.2mug of monoacetylhydrazine/ml, 0.2mug of diacetylhydrazine/ml, 0.02mug of isonicotinic acid/ml and 0.1mug of isonicotinylglycine/ml. 4. In urine, these methods were capable of measuring concentrations of down to about 0.05mug of isoniazid/ml, 0.2mug of acetylisoniazid/ml, 1mug of diacetylhydrazine/ml, 0.1mug of isonicotinic acid/ml and 0.2mug of isonicotinylglycine/ml. 5. The stability of these compounds was studied in serum and urine and a method devised to decrease their decomposition in serum.

Acetates↗

Monitoring saliva concentrations of methaqualone, codeine, secobarbital, diphenhydramine and diazepam after single oral doses.

A preliminary investigation was undertaken to determine the feasibility of monitoring saliva levels of drugs for forensic purposes. Single oral doses of the title compounds were administered to healthy volunteers. Plasma and saliva levels were measured and ratios calculated for all drugs except diazepam. Saliva/plasma ratios for methaqualone, diphenhydramine and secobarbital were all less than one and reasonably consistent between collection times and subjects. The saliva/plasma ratios for codeine were more variable, but always greater than one. Although more detailed investigation is necessary, saliva may be a useful medium for forensic monitoring of drug ingestion.

Administration, Oral↗