An Enzymatic Experiment for the Undergraduate Laboratory Utilizing Commercially Available Material

Applications in chemistry that lead to real world function increase the interest in applied science. For the chemistry student, the reaction between lactose and lactase provides an opportunity to study enzyme kinetics using materials obtained from everyday sources. The effectiveness of the purification of lactose from powdered milk and the efficiency of Lactaid to break down lactose was tested using a glucometer. First enzyme kinetics were established using a known concentrations of lactose. Then, lactose was purified from powdered milk using both centrifugation and crystallization techniques. This purified lactose was mixed with the lactase enzyme from Lactaid and the rate of the reaction was monitored by the Ascencia Contour glucometer. It was found that glucometers can be used to monitor the enzymatic reaction of Lactaid using a lactose substrate purified from powdered milk.