Influence of pH and temperature on the activity of SnO2-bound α-amylase: a genotoxicity assessment of SnO2 nanoparticles.
Immobilization of biologically important molecules on a myriad of nanosized materials has attracted great attention due to their small size, biocompatibility, higher surface-to-volume ratio, and lower toxicity. These properties make nanoparticles (NPs) a superior matrix over bulk material for the immobilization of enzymes and proteins. In the present study, Bacillus amyloliquefaciens α-amylase was immobilized on SnO2 nanoparticles by a simple adsorption mechanism. Nanoparticle-adsorbed enzyme retained 90% of the original enzyme activity. Thermal stability of nanosupport was investigated by thermogravimetric and differential thermal analysis. Scanning electron microscopic studies showed that NPs have porous structure for the high-yield immobilization of α-amylase. The genotoxicity of SnO2-NPs was analyzed by pUC(19) plasmid nicking and comet assay and revealed that no remarkable DNA damage occurred in lymphocytes. The pH-optima was found to be the same for both free and SnO2-NPs bound enzyme, while the temperature-optimum for NPs-adsorbed α-amylase was 5°C higher than its free counterpart. Immobilized enzyme retained more than 70% enzyme activity even after its eight repeated uses.
a Department of Biochemistry , Faculty of Life Sciences, Aligarh Muslim University , Aligarh , India.
Mohd Jahir
MJ
Khan
Qayyum
Q
Husain
D000327:Adsorption; D001407:Bacillus / Q000737:chemistry; D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D020552:Comet Assay; D053938:DNA Fragmentation / Q000187:drug effects; D004800:Enzymes, Immobilized; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000737:chemistry* / Q000633:toxicity / Q000648:ultrastructure; D010957:Plasmids / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D017971:Tin Compounds / Q000737:chemistry* / Q000633:toxicity; D000516:alpha-Amylases / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology
D001426:Bacterial Proteins; D004800:Enzymes, Immobilized; D017971:Tin Compounds; D000516:alpha-Amylases; C045358:stannic oxide