title: 1-naphthyl phosphate: specifications for high-quality substrate for measuring prostatic acid phosphatase activity.
abstract: Ten lots of sodium 1-naphthyl phosphate were compared by spectrophotometry, high-performance liquid chromatography, and kinetic measurements of the activity of human prostatic acid phosphatase (EC 3.1.3.2) in serum. Two lots were readily identified as the 2-naphthyl phosphate salt by spectrophotometry and liquid chromatography. Four of the remaining eight lots of sodium 1-naphthyl phosphate met the following specifications: (a) sodium 1-naphthyl phosphate content greater than 80% by A286nm measurements (epsilon286nm1-NP = 5630 L.mol-1.cm-1) and by enzymic conversion to 1-naphthol (epsilon332nm1-N = 7560 L.mol-1.cm-1), (b) free 1-naphthol less than 3 mmol/mol, (c) inorganic phosphate less than 10 mmol/mol, and (d) the catalytic activity concentration greater than 98% maximum by absorbance assay and greater than 90% maximum by spectrofluorometric assay during simultaneous comparisons of several substrates. The need for detailed specifications and the testing of each batch of sodium 1-naphthyl phosphate is readily demonstrated by this study.
mesh_terms: D000135:Acid Phosphatase / Q000097:blood*; D006801:Humans; D008297:Male; D009281:Naphthalenes / Q000032:analysis / Q000592:standards*; D009943:Organophosphorus Compounds / Q000032:analysis / Q000592:standards*; D011467:Prostate / Q000201:enzymology*; D011786:Quality Control; D012016:Reference Values
chemical_list: D009281:Naphthalenes; D009943:Organophosphorus Compounds; C014694:naphthyl phosphate; D000135:Acid Phosphatase