The　interactions　of　bovine　serum　albumin　(BSA)　with　five　novel　silicon　(IV)　phthalocyanines　(SiPc1-5)　axially　modified　by　nucleosides　(cytidine,　5-N-cytidine,　methyl　cytidine,　uridine　and　methyl　uridine)　derivatives　were　studied　by　fluorescence　spectroscopy.　The　results　show　that　there　are　strong　interactions　between　these　silicon　phthalocyanines　and　BSA　with　a　binding　constant　of　(4.90~83.18)×105　mol-1·L.　Therefore,　the　non-covalent　BSA　conjugate　of　bis(2＇,3＇-O-isopropyl-cytidine-oxy)　phthalocyaninatosilicon　(IV)　(SiPc1)　was　further　been　prepared.　The　molar　ratio　of　phthalocyanine　to　albumin　was　found　to　be　1:1　for　the　obtained　SiPc1-BSA　conjugate.　The　absorption　spectra　of　SiPc1　and　SiPc1-BSA　in　the　visible　region　have　no　significant　difference,　both　showing　an　Q-band　maximum　at　about　686　nm.　It　indicates　that　the　spectroscopic　characteristics　of　SiPc1　are　not　affected　by　binding　to　albumin.　The　SiPc1-BSA　conjugate　exhibits　high　photodynamic　activity　against　human　hepatoma　cell　line　HepG2　with　an　IC50　value　of　3.0×10-7　mol·L-1.　By　comparsion,　SiPc1-BSA　has　a　higher　photodynamic　activity　than　SiPc1　(in　PBS　formation,　IC50=7.0×10-7　mol·L-1),　which　can　be　attributed　to　its　higher　cellular　uptake.　©,　2014,　Science　Press.　All　right　reserved.