Abstract: Disclosed are an agarase mutant with improved thermal stability and application thereof, belonging to the fields of genetic engineering technology and enzyme engineering. The present disclosure provides an agarase mutant, which is obtained by mutating the amino acid at the 86th site, the 373rd site, the 374th site, the 496th site, the 507th site, or the 747th site of agarase with an amino acid sequence as shown in SEQ ID NO. 1. The agarase mutant provided by the present disclosure improves the thermal stability and the hydrolytic activity of the agarase. Compared with the wild type enzyme, the mutant enzyme shows excellent heat resistance and can be industrially used at a relatively high temperature, so that the utilization rate of agar raw materials and the yield of oligosaccharides from agar are improved, and the mutant enzyme has a good industrial application prospect.

Abstract: A sensing device and method in detecting binding energy and binding kinetics between molecules; the sensing device has a sensor, a microfluidic chip and a measurement circuit. The sensor has multiple field effect transistors, and each field effect transistor adopts single-layer single crystal graphene as a conductive channel, thereby having extremely high sensitivity and stability; and the field effect transistors are arranged in an array and are provided with multichannel measurement circuits to detect the binding dynamics processes of different molecules or different copies of the same molecule in parallel so as to meet the high-throughput detection requirements. A compound that is non-covalently bound with the single-layer single crystal graphene as a medium to fix probe molecules on the surface of the conductive channel, thereby retaining the intrinsic structure of the graphene, and improving the signal-to-noise ratio and the sensitivity of the graphene field effect transistor.