IN THIS STUDY, FE3O4 MAGNETIC NANOPARTICLES (MNPS) WERE PREPARED BY CO-PRECIPITATION METHOD AND THIOL-FUNCTIONALIZED WITH (3-MERCAPTOPROPYL) TRIMETHOXYSILANE. THE SIZE AND STRUCTURE OF MNPS AND THIOL-FUNCTIONALIZED ONES WERE CHARACTERIZED BY SCANNING ELECTRON MICROSCOPE (SEM), BET SURFACE AREA AND FTIR. THE LOADING CAPACITY OF FUNCTIONALIZED MAGNETIC NANOPARTICLES AND ACTIVITY OF FREE AND IMMOBILIZED LIPASE WERE DETERMINED. UNDER EXPERIMENTAL CONDITIONS (T=25OC, PH=7), 82.1% OF THE AVAILABLE LIPASE WAS IMMOBILIZED ON THE FUNCTIONALIZED MNPS RESULTING A LIPASE LOADING CAPACITY OF 360 MG/ (G FUNCTIONALIZED MNPS). ENZYME ASSAYS REVEALED THAT LIPASE IMMOBILIZED ON THIOL-FUNCTIONALIZED MAGNETIC NANOPARTICLE DISPLAYED ENHANCED THE LIPASE THERMAL STABILITY IN COMPARISON WITH FREE LIPASE.

SULFUR HETEROCYCLES ARE IMPORTANT COMPOUNDS DUE TO THEIR UNUSUAL PHYSICAL PROPERTIES AND SIGNIFICANT AND VERSATILE BIOLOGICAL ACTIVITY. [1-3]IN 2TTHIS PROJECT AN 2TEFFICIENT METHOD FOR THE SYNTHESIS OF SOME NEW TETRA THIOL [14] ANNULENES WAS INTRODUCED BASE ON USING VINAMIDINIUM SALTS.THE REACTION PATHWAY TO SYNTHESIS OF THE TETRATHIOL [14] ANNULENE DERIVATIVES FROM CORRESPONDING VINAMIDINUM SALTS ARE SHOWN IN SCHEME 1.