| 摘要 |
An apparatus and method to measure the concentration of certain chemical substances in clear, turbid or colored solutions, suspensions or emulsions by two micro pH electrodes connected in series with microbore tubing. Sampling is made by a microdialysis fiber or by dilution in a mixing chamber with specifically formulated buffer systems. The reaction of interest can be started by chemically immobilized or physically confined reagents in a reactor tubing interposed between the two pH electrodes, or by standard mixing techniques. The concentration of an analyte is calculated from the formula: <MATH> where FCAL is a calibration factor experimentally determined and DeltapH0, DeltapH1, are the difference in pH before and after a given chemical reaction producing or absorbing protons has occurred. Substances like glucose, fructose, sucrose, lactate, ascorbate, citrate, acetate, malate, CO2, bicarbonate, creatinine, urea, triglicerides, proteins, enzymes (lypases, proteases, cholinesterases, Glucose-6-Phosphate -dehydrogenase (G6PD), alkaline phosphatase, urease and others) or enzyme inhibiting substances such as antibiotics and organophosphorous pesticides can be rapidly detected in body fluids, hemodialysis ultrafiltrate, milk, beverages (wine, beer, vegetable juices), surface and waste waters, cell suspensions and the like. <IMAGE> |
