RESUMO
Water-soluble gadofullerides exhibited high efficiency as magnetic resonance imaging (MRI) contrast agents. In this paper, we report the conjugation of the newly synthesized gadofulleride, Gd@C82O6(OH) 16(-)(NHCH2CH2COOH)8, with the antibody of green fluorescence protein (anti-GFP), as a model for "tumor targeted" imaging agents based on endohedral metallofullerenes. In this model system, the activity of the anti-GFP conjugate can be conveniently detected by green fluorescence protein (GFP), leading to in vitro experiments more direct and facile than those of tumor antibodies. Objective-type total internal reflection fluorescence microscopy revealed that each gadofulleride aggregate conjugated on average five anti-GFPs, and the activity of anti-GFPs was preserved after conjugation. In addition, the gadofulleride/antibody conjugate exhibited higher water proton relaxivity (12.0 mM (-1) s (-1)) than the parent gadofulleride aggregate (8.1 mM (-1) s (-1)) in phosphate buffered saline at 0.35 T, as also confirmed by T1-weighted images of phantoms. These observations clearly indicate that the synthesized gadofulleride/antibody conjugate not only has targeting potential, but also exhibits higher efficiency as an MRI contrast agent.
Assuntos
Anticorpos/química , Meios de Contraste/síntese química , Gadolínio/química , Imageamento por Ressonância Magnética/métodos , Biotina/química , Fenômenos Químicos , Físico-Química , Proteínas de Fluorescência Verde/imunologia , Indicadores e Reagentes , Conformação Molecular , Peso Molecular , Soroalbumina Bovina/química , Solubilidade , Espectrometria de Fluorescência , Estreptavidina/química , ÁguaRESUMO
A new method for analyzing the ingredients of a pair of optic isomers in ephedra, nor-ephedrine and nor-pseudo-ephedrine, using hyphenated high-efficiency thin layer chromatography (TLC) and surface-enhanced Raman spectroscopy (SERS) techniques, is reported. The results show that the characteristic spectral bands of nor-ephedrine and nor-pseudo-ephedrine can be obtained from the TLC spot with 8 microg sample of about 2.0 mm in diameter. The difference between the SERS and solid spectra was found. Spectral bands at 1004 cm(-1) and 1605 cm(-1) were found greatly enhanced. Molecule was absorbed in surface silver sol by pi electrons in ring. Under similar experimental conditions the spectral information of Levo-nor-ephedrine ramifications TLC-SERS is rich with strong credibility, whereas dextral-nor-ephedrine ramifications show a relatively strong fluorescence backdrop with less spectral information and weak credibility. The effective combination of TLC and SERS can be used to analyse the chemical ingredients with high sensitivity.