On the absorption and metabolism of 35S-ampicillin.
An aqueous solution of 35S-ampicillin and polyethylene glycol (PEG 4000, unabsorbable marker) was administered orally to 6 healthy subjects with gastrointestinal tubes. The minimal absorption of radioactive material, as shown by urinary excretion of label, differed markedly between subjects and averaged 44% (25-67). As the mean cumulative uptake in the proximal jejunum was 31% (24-45), it appeared that some of the radioactivity had been taken up in more distal parts of the gastrointestinal tract. Chromatographic fractionation of gastrointestinal aspirates indicated that more than 95% of the label usually remained attached to the parent compound. The corresponding figure for radioactive material recovered from urine was about 80-85%. A similar degree of decomposition was also found for label excreted in the urine of an additional subject who received 35S-ampicillin intravenously. In this experiment the urine contained 87% of the administered radioactivity.
D000284:Administration, Oral; D000328:Adult; D000667:Ampicillin / Q000008:administration & dosage / Q000378:metabolism*; D002854:Chromatography, Paper; D002855:Chromatography, Thin Layer; D006207:Half-Life; D006801:Humans; D066298:In Vitro Techniques; D007275:Injections, Intravenous; D007408:Intestinal Absorption; D008297:Male; D008875:Middle Aged; D013462:Sulfur Radioisotopes
D013462:Sulfur Radioisotopes; D000667:Ampicillin