Kinetic aspects of analytical chemistry

Kinetic response of an ammonia-selective electrode evaluated for quantitation of ammonia

“…For the concentrations examined here, half-lives vary from 3 to 12. 0 Computed over data range of 176 s. 6 Average of six runs. c Average of four runs.…”

“…The initial-rate and fixed-time kinetic methods in common use (5) have not been attractive for applications with ISE's because they tend to have much larger error coefficients than steady-state (equilibrium) methods (6). However, in recent years a general approach to kinetic determinations has been developed (7)(8)(9) that combines the high speed of kinetic methods with the lower error coefficients of steady-state methods.…”

Design principles of a computer controlled multiplexed absorptiometer for reaction rate analysis

“…The 'steady state' methods normally employed in analytical machines are for the most part too time consuming to suit an emergency system; the need is to make measurements in a matter of thirty seconds or so, a requirement which can be met by using reaction kinetics. The merits of kinetic methods have been reviewed by Pardue [1 ], Malmstadt et al [2] and Moss [3l and the measurement in blood plasma of a number of substances, other than enzymes, using such methods have been described; creatinine, (Cook [4] and Fabiny et al [5]), cholesterol, (Hewitt et al [6]), glucose, (Kadish [71), urea, (Hallett et al [8]), thyroxin-eiodine, (Areq et al [9]) and amylase, (Shipe et al [10]). …”

“…Reviews of the kinetic aspects of analytical chemistry [2] and of the applications of enzymes in analytical chemistry [3] indicate the need for absorptiometers which are able to monitor reactions continually over increasingly long periods of time. The performance of current instrumentation, however, is limited [4]; either the time during which reactions are followed must be limited in order to maintain an acceptable sample throughput, or the sample throughput restricted in order to obtain suitable reaction times.…”

Automation in clinical chemistry: developments and recent trends

“…Ingenuity has allowed both principles to be applied to difficult techniques such as radioimmunoassay, but though kinetic measurements are possible using continuous flow, there is no doubt that in this area discrete analysis systems offer far more scope. It is becoming realised that for many assays, kinetic measurements covering either short of long periods, offer considerable advantages over end-point measurements (Greinke and Mark, 1978), and it could be that an increasing need for kinetic monitoring will lead in the future to a general movement in favour of discrete analysers. Many companies now sell reagents to use with their machines, and increasingly the choice of chemistry for a particular assay has tended to move from the operator to the instrument manufacturer.…”