FLUOROMETRIC INVESTIGATION OF RECOMBINANT HUMAN GROWTH-HORMONE ADSORBED ON SILICA NANOPARTICLES

Since the introduction of recombinantly produced proteins (e.g., recom binant human growth hormone (rhGH)) for therapy, pharmaceutical compan ies have been searching for new techniques to investigate the solid su rface-protein interaction and subsequently increase the shelf life of these molecules. Deducing structural changes of proteins upon adsorpti on at a solid interface with fluorescence has been investigated to dat e mainly with total internal reflection fluorescence. Utilizing an unm odified spectrofluorimeter for investigation, the interaction of rhGH with hydrophilic silica nanoparticles (diameter 9 nm) is monitored thr ough the intrinsic fluorescence of the rhGH's single tryptophan. Gener al trends in the structural changes under different solvent conditions and different folded states are described.