Double Enzyme Activity Of Gold Nanoparticles Supported By Porous Silicon Particles

Natural enzymes usually have high catalytic activity and substrate specificity under mild conditions.In the past decades,researchers have paid a lot of attention to simulating the complex structure and function of natural enzymes,or modifying natural enzymes to improve their stability and tolerance.In recent years,due to the development of nanotechnology,it has been found that many nanomaterials can be used in catalytic reactions,and even nanozyme has been widely used in the treatment of diseases.Nanozyme is a new type of mimic enzyme,it is based on the basis of the nanoparticles,combine nanotechnology and enzymology,because of some characteristics of the nanoparticles?small size effect,quantum effect,surface effect,etc.?and some more advantages,for the design and development of high catalytic activity and stability of the biological system provides a new opportunity,to become the forefront of research topic in recent years.Among them,the gold nanoparticles with good optical and electronic properties,good biocompatibility,and a variety of biological functionalization of usability,also has a wide application in the field of enzymology,but because of the gold nanoparticles are prone to gather,stability is low,and cannot be recycled,etc,its application in the field of enzymology still has a lot of restrictions.This article aims to connect the gold nanoparticles synthesis in porous silicon nanoparticle surface,making the classes with gold nanoparticles enzyme activity,gathered together,and are less able to after the catalytic reaction through the centrifugal recycle and reuse.Due to the large pore volume and large surface area of porous silicon,there are many nano-enzyme catalytic sites and good catalytic activity.Experiments show that the porous silicon load of gold nanoparticles?Si@Au NPs?has a good kind of peroxidase activity,and the classes of hydrogen peroxide enzyme activity,and both enzyme activity of pH and temperature there is a certain degree of dependency,which kind of peroxidase activity of optimum pH=4 in acidic condition,the optimum temperature for 45 ?,steady-state kinetics determination results showed that Si@Au NPs class peroxidase catalytic mechanism for ping-pong mechanism,and₈)=0.65 mM,₈)²²=2.24 mM,K_cat=119 min^–1;The optimal pH of catalase was11,and the optimal temperature was 35 ?,K_m=0.62 mM,and K_cat=1.67 min^-1 under strong alkaline conditions.From the steady-state kinetic capacity,I can prove that we have successfully obtained a nano-enzyme catalytic system with better catalaytic activity.