| dc.description.abstract | Biosensor combines the selectivity of biological recognition element and the sensitivity of the transducer. The application of biosensor as blood glucose measurer for diabetes mellitus patients uses purified enzyme as biological sensor. The substitution of purified enzyme with the microbial cells producing enzymes as biological sensor is carried out to overcome the weaknesses of purified enzyme such as the low stability of the enzyme activity and the high cost. This research was carried out to measure the activity of glucose dehydrogenase (GDH)–the enzyme reacting specifically with glucose as substrate and binding with both pyrolloquinoline quinone (PQQ) and Mg2+ ion as prosthetic group and activator respectively-which is exhibited by escherichia coli, using electrochemical methods Design of experiments only to optimalization the activity of GDH bacterial cells of e. coli is a method of surface response. Optimum conditions of activity of GDH derived cells of e. coli bacteria in the absence of a matrix of nanocomposite zeolite on the process of immobilization is the temperature of 30°C, pH 6, concentration of glucose 15 mM, the concentration of PQQ 3,050 μM. As for the optimum conditions for the activity of GDH bacterial cells of e. coli with matrix nanocomposite zeolite is the temperature of 30°C, pH 6, glucose concentration of 15 mM, the concentration of PQQ 3,050 μM, and nanocomposite zeolite 137,50 mg. The reaction catalyzed by GDH kinetics of Glucose Kinetics equation follows the Lineweaver-Burk. The value of KM app bacterial cells of e. coli with the larger of nanocomposite zeolite mM compared to 1,4580 without nanocomposite of zeolite matrix 0,720 mM. This shows that affinity GDH e. coli immobilization of glucose substrate without nanocomposite zeolite is greater compared to the matrix nanocomposite zeolite.GDH activity stability of bacterial cells is not much different compared with no matrix nanocomposite zeolite. | en |
