RESUMEN
Gd chelates have occupied most of the market of magnetic resonance imaging (MRI) contrast agents for decades. However, there have been some problems (nephrotoxicity, non-specificity, and low r1 ) that limit their applications. Herein, a wet-chemical method is proposed for facile synthesis of poly(acrylic acid) (PAA) stabilized exceedingly small gadolinium oxide nanoparticles (ES-GON-PAA) with an excellent water dispersibility and a size smaller than 2.0 nm, which is a powerful T1 -weighted MRI contrast agent for diagnosis of diseases due to its remarkable relaxivities (r1 = 70.2 ± 1.8 mM-1 s-1 , and r2 /r1 = 1.02 ± 0.03, at 1.5 T). The r1 is much higher and the r2 /r1 is lower than that of the commercial Gd chelates and reported gadolinium oxide nanoparticles (GONs). Further ES-GON-PAA is developed with conjugation of RGD2 (RGD dimer) (i.e., ES-GON-PAA@RGD2) for T1 -weighted MRI of tumors that overexpress RGD receptors (i.e., integrin αv ß3 ). The maximum signal enhancement (ΔSNR) for T1 -weighted MRI of tumors reaches up to 372 ± 56% at 2 h post-injection of ES-GON-PAA@RGD2, which is much higher than commercial Gd-chelates (<80%). Due to the high biocompatibility and high tumor accumulation, ES-GON-PAA@RGD2 with remarkable relaxivities is a promising and powerful T1 -weighted MRI contrast agent.
Asunto(s)
Gadolinio/química , Imagen por Resonancia Magnética , Nanopartículas/química , Neoplasias/diagnóstico por imagen , Tamaño de la Partícula , Resinas Acrílicas/química , Línea Celular Tumoral , Humanos , Nanopartículas/ultraestructuraRESUMEN
Diaminocyclohexane-Pt(ii)-phenalenyl complexes (1 and 2) showed an appropriate balance between efficacy and toxicity. Compound 2 showed nearly two-fold higher tumour growth inhibition than oxaliplatin in a murine NSCLC tumour model, when a combined drug development approach was used. The fluorescent properties of phenalenone were utilized to understand the mechanistic details of the drug.
Asunto(s)
Antineoplásicos/química , Diseño de Fármacos , Platino (Metal)/química , Profármacos/química , Células A549 , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Proliferación Celular/efectos de los fármacos , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Complejos de Coordinación/uso terapéutico , Cristalografía por Rayos X , Humanos , Ligandos , Liposomas/química , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Ratones , Conformación Molecular , Profármacos/farmacología , Profármacos/uso terapéutico , Trasplante HeterólogoRESUMEN
We report the synthesis of a single-walled carbon nanotube (SWNT) graft copolymer. This polymer was prepared by the functionalization of SWNTs with polyethyleneimine (PEI). We used this graft copolymer, SWNT-PEI, as a substrate for cultured neurons and found that it promotes neurite outgrowth and branching.