Studies On Tumor-Targeting Probes For Electron Paramagnetic Resonance Imaging And Fluorescent Imaging

Electron paramagnetic resonance(EPR) is the most effective method to detect and analysis some materials with unpaired electron. Based on the introduction of spin markers, EPR imaging(EPRI) is widely used in biological medicine such as the imaging detect ment and diagnosis some diseases of organs or tissues in vivo. Currently, the EPRI spin probes, such as 2,2,6,6-tetrmethyl-1-piperidinoxy(TEMPO) and 5-carboxy-1,1,3,3-tetramethylisoindolin-2-yloxyl(CTMIO), are all low molecular weight compounds, which have short retention time in vivo, no targeting property and nonspecific distribution to tumors, and then cannot show the good enhanced imaging in tumors. Thus a series of tumor-targeting EPRI spin probes were synthesized and studied to overcome these insufficiencies in this thesis. The main contents of this thesis were summarized as follows:The research progresses of nitroxides, porphyrins, fullerenol, Glypican-3 monoclonal antibody(GPC3-mAb) and naphthalimide were reviewed briefly. The principle and application of EPR technique were described in detail.A series of porphyrins containing isoindoline nitroxides were synthesized by the reaction between 5-phenyldipyrromethane, 5-(4’-nitrophenyl)-dipyrromethane and 5-formyl-1,1,3,3-tetramethylisoindolin-2-yloxyl(FTMIO) using improved Alder-Longo method. These spin labeled porphyrins included 5,10,15-trisphenyl-20-(1’,1’,3’,3’-tetramethylisoindolin-2’-yloxyl-5’-yl)porphyrin(TPTMIOP), 5,10-bisphenyl-15-nitrophenyl-20-(1’,1’,3’,3’-tetramethylisoindolin-2’-yloxyl-5’-yl)porphyrin(BPNPTMIOP), 5-phenyl-10,15-bisnitrophenyl 20-(1’,1’,3’,3’-tetramethylisoindolin-2’-yloxyl-5’-yl)porphyrin(PBNPTMIOP), 5,15-bisphenyl-10,20-bis(1’,1’,3’,3’-tetramethylisoindolin-2’-yloxyl-5’-yl) porphyrin(p-BPBTMIOP), 5,10- bisphenyl-15,20-bis(1’,1’,3’,3’-tetramethylisoindolin-2’-yloxyl-5’-yl)porphyrin(o-BPBTMIOP), 5-phenyl-15-nitrophenyl-10,20-bis(1’,1’,3’,3’-tetramethylisoindolin-2’-yloxyl-5’-yl)porphyrin(p-PNPBTMIOP), 5-phenyl-10-nitrophenyl-15,20-bis(1’,1’,3’,3’-tetramethylisoindolin-2’-yloxyl-5’-yl)porphyrin( o-PNPBTMIOP) and 5-phenyl-10,15,20-tris(1’,1’,3’,3’-tetramethylisoindolin-2’-yloxyl-5’-yl)porphyrin(PTTMIOP)and were further characterizated by FT-IR, UV and EI MS, respectively. The fluorescence, cyclic voltammetry and EPR properties of these spin labeled porphyrins were also evaluated herein. Compared to TMIO, these spin labeled porphyrins possessed similar EPR, electrochemical and redox properties. Meanwhile, the fluorescence-suppression and EPR characteristic of three line signals with resolvable superhyperfine splittings were observed.5,10,15-Tris(4’’-carboethoxymethyleneoxyphenyl)-20-(1’,1’,3’,3’-tetramethylisoindolin-2’-yloxyl-5’-yl)porphyrin(TECPTMIOP) was synthesized by the Lindsey cyclization reaction between 5-(4’-carboethoxymethyleneoxyphenyl)dipyrromethane and 5-formyl-1,1,3,3-tetramethylisoindolin-2-yloxyl(FTMIO) and further used to make a corresponding water-soluble 5,10,15-tris[(4’’-carboxymethyleneoxyphenyl]-20-(1’,1’,3’,3’-tetramethylisoindolin-2’-yloxyl-5’-yl)porphyrin(TCPTMIOP). Subsequently, TCPTMIOP was attached covalently to Glypican-3 monoclonal antibody(GPC3-mAb) to make a tumor-targeting EPRI spin probe(TCPTMIOP-GPC3-mAb). This spin probe was further characterizated by FT-IR, UV and EI MS. The fluorescence, cyclic voltammetry and EPR properties of the spin probe were also evaluated herein. The spin probe possessed similar electrochemical and redox properties as TMIO and similar fluorescent properties as TCPTMIOP.A tumor-targeting EPRI-fluorescence imaging probe mAb-GPC3-C60(OH)10-(TMIO)4-(Ni)3 was synthesized by the incorporation of 5-formyl-1,1,3,3-tetramethylisoindolin-2-yloxyl, Glypican-3 monoclonal antibody(GPC3-mAb) and naphthalimide into water-soluble fullerenol. This probe was further characterizated by FT-IR and EI MS. The fluorescence, cyclic voltammetry, particle size, electrophoresis and EPR properties of spin probe were also evaluated herein. The probe had similar electrochemical and redox properties as TMIO and similar fluorescent properties as naphthalimide. This probe can disperse homogeneously in aqueous solution and be potential to be used as a tumor-targeting EPRI-fluorescence imaging probe.