Surface-modified with tetraethoxysilane (TEOS) Superparamagnetic Nanoparticles (SNPs) were successfully synthesized to enhance their hydrophobicity and bio-affinity for an esterase. The obtained SNPs possessed large surface area, high conductivity and improved antimicrobial activity. An esterase from Bacillus pumilus was efficiently immobilized on silane functionalized SNPs and its successful binding was confirmed by both FTIR and FE-SEM. The low Michaelis Menten constant (K-m) (similar to 12% lesser than free enzyme) of the SNPs-immobilized/bounded esterase (SNPs-Est) suggested its preeminent compatibility for the substrate (p-nitrophenyl acetate) than the free esterase. SNPs-Est retained half of its original activity even after 11.3 h of incubation and remained vigorous over 14 cycles of repetitive use at 45 degrees C. SNPs-Est was also checked out for successful synthesis of ethyl pyruvate (96% conversion of pyruvic acid into ethyl pyruvate), a flavor ester using High Performance Liquid Chromatography (HPLC) and( 1)H-Nuclear Magnetic Resonance (H-1-NMR) studies.