Stable and efficient immobilization technique of aldolase under consecutive microwave irradiation at low temperature.

To establish a stable and efficient immobilization technique under microwave irradiation, a focused microwave reaction system was used, where the temperature was set appropriately in the microwave system and cooling module to produce consecutive microwave irradiation. 2-Deoxy-D-ribose-5-phosphate aldolase (DERA) was rapidly and efficiently immobilized in mesocellular siliceous foams (MCFs) under microwave irradiation. When the output power in the microwave system was set to 30W, after 3 min, 88.4% of the enzyme protein was coupled to the wall of the support pores and the specific activity of the immobilized enzyme was 2.24 U mg(-1), 149.2% higher than that of the free enzyme and 157.0% higher than that of the non-microwave-assisted immobilized enzyme. In catalysis, microwave-assisted immobilized DERA tolerated a wider range of both pH and temperature than other DERA preparations. The thermal and storage stabilities were also significantly improved. This focused: microwave-assisted immobilization technique has proven to be simple, stable and highly efficient. This technique could also be applied to other enzyme immobilizations. (C) 2010 Elsevier Lid. All rights reserved.