Mansur Alexandra A P, de Carvalho Sandhra M, Mansur Herman S
Center of Nanoscience, Nanotechnology and Innovation-CeNano(2)I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, Escola de Engenharia, Bloco 2/2233, Pampulha, Belo Horizonte 31.270-901 MG, Brazil.
Center of Nanoscience, Nanotechnology and Innovation-CeNano(2)I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, Escola de Engenharia, Bloco 2/2233, Pampulha, Belo Horizonte 31.270-901 MG, Brazil.
Int J Biol Macromol. 2016 Jan;82:780-9. doi: 10.1016/j.ijbiomac.2015.10.047. Epub 2015 Oct 21.
Nanobiomaterials can be engineered to recognize cancer-specific receptors at the cellular level for diagnostic and therapeutic purposes. In this work, we report the synthesis of novel multifunctional nanoconjugates composed of fluorescent inorganic semiconductor quantum dot (QD) cores and tripeptide-modified polysaccharide organic shells. These structures were designed for targeting and imaging the αvβ3 integrin receptors of cancer cells. Initially, chitosan was covalently bound with the RGD peptide using a crosslinker to form bioconjugates (RGD-chitosan), which were later utilized as capping ligands for the production of surface-functionalized CdS QDs via a single-step process in aqueous media at room temperature. These core-shell nanostructures were extensively characterized by UV-vis spectroscopy, photoluminescence (PL) spectroscopy, Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), zeta potential (ZP) and dynamic light scattering (DLS). The TEM images and the UV-vis absorption results indicated the formation of ultra-small CdS QD nanocrystals with average diameters between 2.0 and 3.0 nm. In addition, the PL results demonstrated that the nanobioconjugates exhibited intense green fluorescence under excitation. The CdS-RGD-chitosan systems were effective at specific targeting integrin when assayed in vitro using two model cell cultures, HEK 293 (non-cancerous human embryonic kidney cell) and SAOS (cancerous sarcoma osteogenic-derived cells) imaged using fluorescence microscopy.
纳米生物材料可以被设计成在细胞水平上识别癌症特异性受体，用于诊断和治疗目的。在这项工作中，我们报告了由荧光无机半导体量子点（QD）核心和三肽修饰的多糖有机壳组成的新型多功能纳米共轭物的合成。这些结构被设计用于靶向和成像癌细胞的αvβ3整合素受体。最初，壳聚糖使用交联剂与RGD肽共价结合形成生物共轭物（RGD-壳聚糖），随后在室温下于水性介质中通过一步法将其用作封端配体，用于生产表面功能化的硫化镉量子点。这些核壳纳米结构通过紫外可见光谱、光致发光（PL）光谱、傅里叶变换红外光谱（FTIR）透射电子显微镜（TEM）、zeta电位（ZP）和动态光散射（DLS）进行了广泛表征。透射电子显微镜图像和紫外可见吸收结果表明形成了平均直径在2.0至3.0纳米之间的超小硫化镉量子点纳米晶体。此外，光致发光结果表明，纳米生物共轭物在激发下呈现强烈的绿色荧光。当使用荧光显微镜对两种模型细胞培养物HEK 293（非癌性人胚胎肾细胞）和SAOS（癌性骨肉瘤衍生细胞）进行体外测定时，硫化镉-RGD-壳聚糖系统在特异性靶向整合素方面是有效的。
