Computer interfaced stopped-flow kinetics

Stopped-flow kinetics is a method in which two reactants are forced into a mixing chamber and their flow abruptly stopped. The progress of the reaction is monitored at an observation window, a short distance from the chamber along the flow path. Traditionally, data from the stopped-flow has been collected on film from a storage oscilloscope. Points were then measured from the photograph and results tabulated by hand. With the computer now available at a reasonable cost, this method of data acquisition is unacceptable.

Presented in this work is an 8085-based, single board microcomputer system to acquire and store data from the stopped-flow apparatus. The system is user friendly, allowing the operator to set parameters such as rate, point total, and window of transmittance. The data once acquired, can be displayed at the work station or transmitted to a host computer for later manipulation.

Data from a Beer's law investigation and from the well-documented FeCl3- KSCN reaction will be presented as a system evaluation.