BACKGROUND: : Many different methods have been used to assay amylase activity, using nitrophenylated oligosaccharides as substrate; however, the hydrolysis steps in these methods are complex. METHODS: : We developed a new continuously monitoring assay for amylase activity in biological fluids, using 2-chloro-4-nitrophenyl-4-O-beta-D-galactopyranosylmaltoside (GalG2CNP) as the substrate; this assay was used with anti-human salivary amylase monoclonal antibodies for specific determination of the pancreatic isoenzyme. Amylase converted GalG2CNP into beta-D-galactopyranosylmaltose and 2-chloro-4-nitrophenol, which was measured at 405 nm. RESULTS: : GalG2CNP was cleaved between 2-chloro-4-nitrophenol and beta-D-galactopyranosylmaltose and did not undergo transfer reactions. The within-assay CVs (n = 20) for total amylase (T-AMY) and pancreatic amylase (P-AMY) were 0.6-1.6% and 0.5-2.5%, respectively; and day-to-day CVs (n = 10) for T-AMY and P-AMY were 0.8-3.7% and 0.6-4.1%, respectively. T-AMY and P-AMY activities in serum or urine obtained by the proposed method correlated well with those determined by the 2-chloro-4-nitrophenyl 4-O-beta-D-galactopyranosyl-beta-maltotetraoside method or the modified IFCC method. CONCLUSIONS: : This novel assay for T-AMY and P-AMY measures both activities stoichiometrically, directly, and easily, and may be suitable for routine procedures.
BACKGROUND: : Many different methods have been used to assay amylase activity, using nitrophenylated oligosaccharides as substrate; however, the hydrolysis steps in these methods are complex. METHODS: : We developed a new continuously monitoring assay for amylase activity in biological fluids, using 2-chloro-4-nitrophenyl-4-O-beta-D-galactopyranosylmaltoside (GalG2CNP) as the substrate; this assay was used with anti-human salivary amylase monoclonal antibodies for specific determination of the pancreatic isoenzyme. Amylase converted GalG2CNP into beta-D-galactopyranosylmaltose and 2-chloro-4-nitrophenol, which was measured at 405 nm. RESULTS: : GalG2CNP was cleaved between 2-chloro-4-nitrophenol and beta-D-galactopyranosylmaltose and did not undergo transfer reactions. The within-assay CVs (n = 20) for total amylase (T-AMY) and pancreatic amylase (P-AMY) were 0.6-1.6% and 0.5-2.5%, respectively; and day-to-day CVs (n = 10) for T-AMY and P-AMY were 0.8-3.7% and 0.6-4.1%, respectively. T-AMY and P-AMY activities in serum or urine obtained by the proposed method correlated well with those determined by the 2-chloro-4-nitrophenyl 4-O-beta-D-galactopyranosyl-beta-maltotetraoside method or the modified IFCC method. CONCLUSIONS: : This novel assay for T-AMY and P-AMY measures both activities stoichiometrically, directly, and easily, and may be suitable for routine procedures.
Authors: Susanne Proksch; Thorsten Steinberg; Constantin Keller; Martin Wolkewitz; Margit Wiedmann-Al-Ahmad; Guenter Finkenzeller; Christian Hannig; Elmar Hellwig; Ali Al-Ahmad Journal: Clin Oral Investig Date: 2011-01-19 Impact factor: 3.573
Authors: E P Almeida; A C Almeida; F F Almeida; J Montessi; C A Gomes; L E V V C Ferreira Journal: Braz J Med Biol Res Date: 2015-07-10 Impact factor: 2.590