Mariano Rodolfo Nicolás, Alberti Diego, Cutrin Juan Carlos, Geninatti Crich Simonetta, Aime Silvio
Department of Molecular Biotechnology and Health Sciences, University of Torino , via Nizza 52, Torino, Italy.
Mol Pharm. 2014 Nov 3;11(11):4100-6. doi: 10.1021/mp5002747. Epub 2014 Sep 29.
An amphiphilic Gd(III) complex has been efficiently loaded in polylactic-co-glycolic acid nanoparticles (PLGA-NPs) to yield a novel, high sensitive magnetic resonance imaging (MRI) contrast agent for imaging guided drug delivery applications. As the Gd(III) complex is soluble in organic solvents, the nanoparticles were prepared as oil/water emulsions. PLGA-NPs were stable, in buffer, for more than 1 week without any release of the incorporated agents. The millimolar relaxivity of the Gd(III) complex incorporated in the particles (140 nm diameter) was of 21.7 mM(-1) s(-1) at 21.5 MHz, a value that is about 5 times higher than that observed with the commercially available contrast agents used in clinic. The relaxometric efficiency of these particles resulted inversely proportional to the particle size measured by dynamic light scattering. The high stability and sensitivity of PLGA-NPs allowed their accumulation in vivo in murine melanoma xenograft as shown in the corresponding MR images. Once loaded with drug and contrast agents, PLGA nanoparticles can be proposed as efficient theranostic MRI agents.
一种两亲性钆（III）配合物已被高效地负载于聚乳酸 - 乙醇酸共聚物纳米颗粒（PLGA - NPs）中，以产生一种新型的、高灵敏度的磁共振成像（MRI）造影剂，用于成像引导的药物递送应用。由于钆（III）配合物可溶于有机溶剂，纳米颗粒被制备成油/水乳液。PLGA - NPs在缓冲液中稳定，超过1周未出现包封剂的任何释放。包封在直径为140 nm颗粒中的钆（III）配合物在21.5 MHz时的毫摩尔弛豫率为21.7 mM⁻¹ s⁻¹，该值比临床使用的市售造影剂所观察到的值高约5倍。这些颗粒的弛豫测量效率与通过动态光散射测量的粒径成反比。如相应的MR图像所示，PLGA - NPs的高稳定性和灵敏度使其能够在小鼠黑色素瘤异种移植瘤中体内蓄积。一旦负载药物和造影剂，PLGA纳米颗粒可被用作高效的治疗诊断MRI剂。
