Two flow injection systems for detection of acid phosphatase (ACP) activity have been investigated. In both systems, monofluorophosphate (MFP) as a specific and inexpensive substrate for ACP and LaF(3) membrane-based ion-selective electrode as a potentiometric detector of fluoride ions released in the course of the biocatalytic hydrolysis of MFP were applied. The continuous-flow mode was modified to include a stopped-flow segment, with separate valve control, to increase reaction time and minimize dispersion while increasing system throughput.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
June 2003
Micellar electrokinetic chromatography with UV absorbance detection has been applied for fast and selective determination of creatinine in samples of postdialysate fluid. Optimization of the method was performed, with the best results being obtained using a 30 mM borate-100 mM sodium dodecyl sulphate background electrolyte, pH 9, with the detector set at 235 nm and an applied voltage of 17 kV across a fused-silica capillary of 67 cm/75 micro m I.D.
View Article and Find Full Text PDFThe pH is one of the most important parameters for char-acterizing the chemical properties of an aqueous solution. The glass eiectrode is by far the most commonly used pH sensor. The determination of pH in special situations, e.
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