Quantitative Detection Limit Research Articles

Quantitative detection limit in histochemistry. II

Quantitative detection limit in histochemistry. II

Cherry gum: C. L. Butler and Leonard H. Cretcher ( Journal of the American Pharmaceutical Association, 1932, 21, 24–30)

A gas chromatographic method is described for the determination of chloroacetyl chloride (CAC) in air in the presence of monochloroacetic acid (MCA). Air containing CAC was bubbled through a reactant solution of 2,4,6-trichlorophenol (TCP) and pyridine in toluene to produce the derivative 2,4,6-trichlorophenyl chloroacetate (TCPC). Excess TCP was removed by extractions with 1 N sodium hydroxide, and TCPC was determined via electron capture gas chromatography. An average recovery of 76 ± 4% (mean ±S.D.) was obtained when CAC was added directly to the reactant solution. When air samples containing CAC were scrubbed and analyzed, recoveries averaged 70 ± 5% (mean ±S.D.). The quantitative detection limit (2.5 × noise) was 1 ng CAC/ml in the extracted organic layer [1 ppb1 in air for a 5-1 sample]. The general applicability of this method for volatile acid halides was also explored.

Spinasterol: Merrill C. Hart and Frederick W. Heyl ( Journal of Biological Chemistry, 1932, 95, 311–315)

A gas chromatographic method is described for the determination of chloroacetyl chloride (CAC) in air in the presence of monochloroacetic acid (MCA). Air containing CAC was bubbled through a reactant solution of 2,4,6-trichlorophenol (TCP) and pyridine in toluene to produce the derivative 2,4,6-trichlorophenyl chloroacetate (TCPC). Excess TCP was removed by extractions with 1 N sodium hydroxide, and TCPC was determined via electron capture gas chromatography. An average recovery of 76 ± 4% (mean ±S.D.) was obtained when CAC was added directly to the reactant solution. When air samples containing CAC were scrubbed and analyzed, recoveries averaged 70 ± 5% (mean ±S.D.). The quantitative detection limit (2.5 × noise) was 1 ng CAC/ml in the extracted organic layer [1 ppb1 in air for a 5-1 sample]. The general applicability of this method for volatile acid halides was also explored.