高等学校化学研究 ›› 2014, Vol. 30 ›› Issue (4): 549-555.doi: 10.1007/s40242-014-4015-0
LIU Yun1, HUANG Yan1, BOAMAH Peter Osei1, ZHANG Qi1,2, LIU Yuanyuan1, HUA Mingqing1
LIU Yun1, HUANG Yan1, BOAMAH Peter Osei1, ZHANG Qi1,2, LIU Yuanyuan1, HUA Mingqing1
摘要:
Mn-TCPP-CSn(n=6, 11, 20) as a type of potential magnetic resonance imaging(MRI) contrast agents were synthesized via manganese(II) meso-tetra(4-carboxyphenyl) porphyrin(Mn-TCPP) modified with chitosan oligosaccharides(CSn). Experimental data of infared(IR), UV-Vis, MS, inductively coupled plasma-atomic emission spectrometer(ICP-AES) and size exclusion chromatography evidenced the formation of Mn-TCPP-CSn. The stability results show that Mn-TCPP-CSn in aqueous solution was stable enough to prevent Mn(II) ions from leaking. The magnetic properties in vitro indicate that Mn-TCPP-CS20 possesses higher longitudinal relaxivity(r1=10.38 L·mmol-1·s-1) in aqueous solution than unmodified porphyrin Mn-TCPPNa4[manganese(II) meso-tetra(4-carboxyphenyl) porphyrin, tetrasodium salt](r1=5.10 L·mmol-1·s-1) and the commercial contrast agent Gd-DTPA(r1=4.05 L·mmol-1·s-1). The preliminary T1-weighted flash image studies in vitro show that the contrast and the imaging signal of Mn-TCPP-CSn were superior to those of Mn-TCPPNa4 and Gd-DTPA under the same conditions. The 3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide(MTT) assay shows that Mn-TCPP-CSn has a good biocompatibility. In addition, the thermodynamical parameters(ΔH<0, ΔS<0, ΔG<0) of Mn-TCPP-CSn bound to bovine serum albumin(BSA) show that Mn-TCPP-CSn could bind to BSA spontaneously, where the binding complex was stabilized mainly by van der Waals interactions and hydrogen bonds. These results suggest that Mn-TCPP-CSn have the advantage of becoming a potential MRI contrast agent.