Water-soluble phosphate-functionalized polyfluorene as fluorescence biosensors toward cytochrome c  

作　　者：QIN ChuanJiang TONG Hui WANG LiXiang 

机构地区：[1]State Key Laboratory of Polymer Physics and Chemistry,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China

出　　处：《Science China Chemistry》2009年第6期833-839,共7页中国科学（化学英文版）

基　　金：Supported by the National Natural Science Foundation of China (Grant Nos. 20574067 & 50633040);the Science Fund for Creative Research Groups (Grant No. 20621401);the 973 Project (Grant No. 2002CB613402)

摘　　要：An anionic water-soluble polyfluorene derivative, poly(9,9-bis(6′-phosphatehexyl)fluorene-alt-1,4-pheny lene) sodium salt (PFHPNa), was synthesized by Suzuki coupling reaction in DMF/water. Polymer PFHPNa was well soluble in water with a strong blue fluorescence emission. Effect of the side chain length on fluorescence sensory properties was studied by comparing quenching efficiencies toward different quenchers of PFHPNa with a reported polymer poly(9,9-bis(3′-phosphatepropyl)fluorene-alt-1,4-phenylene) sodium salt (PFPPNa), which have different side chains in length. For small molecular quenchers (methylviologen, MV2+) and meso-5,10,15,20-tetrakis-(N-methyl-4-pyridyl)porphine (TMPyP4), polymer PFHPNa had lower sensitivity due to the much longer side chain length. The positively charged metalloprotein cytochrome c could quench fluorescence of conjugated polymers via energy transfer and electron transfer. Moreover, polymer PFHPNa showed higher fluorescence quenching toward large biomolecules than PFPPNa. The corresponding Stern-Volmer (Ksv) value of polymer PFHPNa was determined to be 2.1×108 M-1 for cytochrome c. It could be used as a sensitive and selective fluorescence sensor for protein cytochrome c.An anionic water-soluble polyfluorene derivative, poly(9,9-bis(6′-phosphatehexyl)fluorene-alt-1,4-phenylene) sodium salt (PFHPNa), was synthesized by Suzuki coupling reaction in DMF/water. Polymer PFHPNa was well soluble in water with a strong blue fluorescence emission. Effect of the side chain length on fluorescence sensory properties was studied by comparing quenching efficiencies toward different quenchers of PFHPNa with a reported polymer poly(9,9-bis(3′-phosphatepropyl)fluorene-alt-1,4-phenylene) sodium salt (PFPPNa), which have different side chains in length. For small molecular quenchers (methylviologen, MV2+) and meso-5,10,15,20-tetrakis-(N-methyl-4-pyridyl)porphine (TMPyP4), polymer PFHPNa had lower sensitivity due to the much longer side chain length. The positively charged metalloprotein cytochrome c could quench fluorescence of conjugated polymers via energy transfer and electron transfer. Moreover, polymer PFHPNa showed higher fluorescence quenching toward large biomolecules than PFPPNa. The corresponding Stern-Volmer (K sv) value of polymer PFHPNa was determined to be 2.1×108 M?1 for cytochrome c. It could be used as a sensitive and selective fluorescence sensor for protein cytochrome c.

关 键 词：CONJUGATED polymer FLUORESCENCE sensor WATER-SOLUBLE side chain 

分 类 号：O657.1[理学—分析化学]