The drug carrier function of single protein nanoparticles,i.e.,each individual protein molecule covered by a very thin,porous and few nanometer thick polymer layer,has been investigated.This layer around protein molec...The drug carrier function of single protein nanoparticles,i.e.,each individual protein molecule covered by a very thin,porous and few nanometer thick polymer layer,has been investigated.This layer around protein molecule is very thin,about 3-5 nm thick and highly porous,thus it does not reduce seriously the enzymatic function of protein molecule.The spatial structure of encapsulated protein molecule,which is essential in its function,can be stabilized by this polymer layer.Bovine serum albumin was used as protein drug molecule and it was encapsulated with acrylamide-bisarylamide random copolymer.The polymerization,starting from the modified sites of the surface of bovine serum albumin molecules was initiated by TEMED(tetramethylethylenediamine).These single albumin nanoparticles were painted with fluorescein isothiocyanate.This material was then injected into the inferior vena cava of rats.The treated rats were decapitated after 1 to 10 minutes and its brain was investigated by fluorescent microscopy.It was proved that bovine serum albumin molecules as drugs encapsulated in polymer nano-layer with a reduced size(about 10 nm)can pass through the blood brain barrier.The results suggest that this method is capable of transformation of biomacromolecules to access the brain tissue via the blood.展开更多
文摘The drug carrier function of single protein nanoparticles,i.e.,each individual protein molecule covered by a very thin,porous and few nanometer thick polymer layer,has been investigated.This layer around protein molecule is very thin,about 3-5 nm thick and highly porous,thus it does not reduce seriously the enzymatic function of protein molecule.The spatial structure of encapsulated protein molecule,which is essential in its function,can be stabilized by this polymer layer.Bovine serum albumin was used as protein drug molecule and it was encapsulated with acrylamide-bisarylamide random copolymer.The polymerization,starting from the modified sites of the surface of bovine serum albumin molecules was initiated by TEMED(tetramethylethylenediamine).These single albumin nanoparticles were painted with fluorescein isothiocyanate.This material was then injected into the inferior vena cava of rats.The treated rats were decapitated after 1 to 10 minutes and its brain was investigated by fluorescent microscopy.It was proved that bovine serum albumin molecules as drugs encapsulated in polymer nano-layer with a reduced size(about 10 nm)can pass through the blood brain barrier.The results suggest that this method is capable of transformation of biomacromolecules to access the brain tissue via the blood.
