Oxopentanedioic acid isonicotinoyl hydrazone (H_2L) and its five rare earth complexes were synthesized with a view to further investigating MRI activities of the polycarboxylic Schiff base complexes. The complexes wer...Oxopentanedioic acid isonicotinoyl hydrazone (H_2L) and its five rare earth complexes were synthesized with a view to further investigating MRI activities of the polycarboxylic Schiff base complexes. The complexes were characterized on the basis of elemental analyses, IR, UV, (()~1H) NMR spectra and thermal analyses. The general formula of the complexes is [Ln(HL)(H_2O)_2]Cl_2·H_2O (where Ln(Ⅲ)=La, Pr, Nd, Eu and Gd). In addition, the relaxivity ( R _1) of the Gd-complex was determined by INVREC Au program.展开更多
Synthesis and characterization of NMR T-1 relaxation properties of the title complexes and several transition metal-EDTA-bis[ tris(hydroxymethyl methylamide] complexes were performed for searching new contrast agents ...Synthesis and characterization of NMR T-1 relaxation properties of the title complexes and several transition metal-EDTA-bis[ tris(hydroxymethyl methylamide] complexes were performed for searching new contrast agents for magnetic resonance imaging(MRI). The ligands, abbr. to DTPA-BTris and EDTA-BTris, were obtained by modifying DTPA and EDTA with tris(hydroxymethyl) aminomethane. It was found that the relaxivities of solutions of the modified complexes in vitro are correspondingly greater than those of the parent complexes. For GdDTPA-BTris, MnEDTA-BTris, and FeEDTA-BTris, the relaxometry of lattice relaxation(R-1) is 5.4, 3.1, and 1.9 L.mmol(-1).s(-1) vs. 5.2, 2.8 and 1.7 L.mmol(-1).s(-1) for GdDTPA, MnEDTA, and FeEDTA, respectively. Additionally, the present complexes have the favorable properties such as high water solubility and chemical stability required of clinical useful contrast agent.展开更多
Gadolinium(Ⅲ)-based T_(1) contrast agents have been widely used in clinical MRI.In this study,salicylic acid-gadolinium chelate was prepared via directly coordination reaction of gadolinium ion and salicylic acid.The...Gadolinium(Ⅲ)-based T_(1) contrast agents have been widely used in clinical MRI.In this study,salicylic acid-gadolinium chelate was prepared via directly coordination reaction of gadolinium ion and salicylic acid.Then,three polyethylene glycols with different molecular weight were modified on the surface of salicylic acid-gadolinium by simple chemical coupling to construct three core-shell structural Gd based composites.The scanning electron microscopy(SEM)and transmission electron microscopy(TEM)characterization results show that the composite is a spherical particle with a diameter of about 100-200 nm.The longitudinal relaxation rate r_(1) of the Gal-PEG-2000 is 11.097(mmol/L)^(-1)/s,and the ratio of r_(2)/r_(1) is as low as 2.53.The composite shows good liver and intestines MRI performances after being used in in vivo imaging,showing a good prospect of biological application.展开更多
文摘Oxopentanedioic acid isonicotinoyl hydrazone (H_2L) and its five rare earth complexes were synthesized with a view to further investigating MRI activities of the polycarboxylic Schiff base complexes. The complexes were characterized on the basis of elemental analyses, IR, UV, (()~1H) NMR spectra and thermal analyses. The general formula of the complexes is [Ln(HL)(H_2O)_2]Cl_2·H_2O (where Ln(Ⅲ)=La, Pr, Nd, Eu and Gd). In addition, the relaxivity ( R _1) of the Gd-complex was determined by INVREC Au program.
文摘Synthesis and characterization of NMR T-1 relaxation properties of the title complexes and several transition metal-EDTA-bis[ tris(hydroxymethyl methylamide] complexes were performed for searching new contrast agents for magnetic resonance imaging(MRI). The ligands, abbr. to DTPA-BTris and EDTA-BTris, were obtained by modifying DTPA and EDTA with tris(hydroxymethyl) aminomethane. It was found that the relaxivities of solutions of the modified complexes in vitro are correspondingly greater than those of the parent complexes. For GdDTPA-BTris, MnEDTA-BTris, and FeEDTA-BTris, the relaxometry of lattice relaxation(R-1) is 5.4, 3.1, and 1.9 L.mmol(-1).s(-1) vs. 5.2, 2.8 and 1.7 L.mmol(-1).s(-1) for GdDTPA, MnEDTA, and FeEDTA, respectively. Additionally, the present complexes have the favorable properties such as high water solubility and chemical stability required of clinical useful contrast agent.
基金Project supported by the Natural Science Foundation of Gansu Province(20JR10RA511,2019B-084)。
文摘Gadolinium(Ⅲ)-based T_(1) contrast agents have been widely used in clinical MRI.In this study,salicylic acid-gadolinium chelate was prepared via directly coordination reaction of gadolinium ion and salicylic acid.Then,three polyethylene glycols with different molecular weight were modified on the surface of salicylic acid-gadolinium by simple chemical coupling to construct three core-shell structural Gd based composites.The scanning electron microscopy(SEM)and transmission electron microscopy(TEM)characterization results show that the composite is a spherical particle with a diameter of about 100-200 nm.The longitudinal relaxation rate r_(1) of the Gal-PEG-2000 is 11.097(mmol/L)^(-1)/s,and the ratio of r_(2)/r_(1) is as low as 2.53.The composite shows good liver and intestines MRI performances after being used in in vivo imaging,showing a good prospect of biological application.
