title: Construction of a microprocessor-controlled pulsed quench-flow apparatus for the study of fast chemical and biochemical reactions.
abstract: The construction and operation of a microprocessor-controlled quenched-flow machine are described. Two sets of syringes are moved by high-torque stepping motors to achieve any desired mixing scheme. The dead time of the instrument is pulsed quench-flow operation is of the order of 10 ms. The fastest possible reaction time is 12 ms with the reaction chamber used here; this might be extended downward with other reaction chambers. The reactant volume required is low; 1 ml of solution for each reactant is sufficient for more than 40 kinetic measurements. The machine is tested by alkaline hydrolysis of 2,4-dinitrophenylacetate and used in the investigation of the reaction mechanism of the EcoRI restriction endonuclease and of GTPase activity of ribosomes.
mesh_terms: D001671:Biochemistry / Q000295:instrumentation; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation; D004262:DNA Restriction Enzymes / Q000378:metabolism; D004279:DNA, Viral / Q000378:metabolism; D015246:Deoxyribonuclease EcoRI; D004581:Electronics; D020558:GTP Phosphohydrolases / Q000378:metabolism; D006868:Hydrolysis; D008838:Microcomputers; D010648:Phenylacetates; D012212:Rheology; D012270:Ribosomes / Q000201:enzymology
chemical_list: D004279:DNA, Viral; D010648:Phenylacetates; C026869:2,4-dinitrophenylacetic acid; D004262:DNA Restriction Enzymes; D015246:Deoxyribonuclease EcoRI; D020558:GTP Phosphohydrolases