Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province and ‡School of Life Sciences, Lanzhou University , Lanzhou 730000, China.
Bioconjug Chem. 2012 May 16;23(5):1010-21. doi: 10.1021/bc300008k. Epub 2012 Apr 17.
We developed a novel chitosan-based luminescent/magnetic hybrid nanoparticles with folate-conjugated tetrapeptide composites (CLMNPs-tetrapeptide-FA) by conjugation in situ. First, chitosan, CdTe quantum dots (QDs), and superparamagnetic iron oxide were directly gelled into ternary hybrid nanogels. Subsequently, tetrapeptides (GFFG and LGPV) and folate were conjugated orderly into the hybrid nanoparticles. The morphology, composition, and properties of the as-prepared copolymers have also been characterized and determined using TEM, EDX, XRD, FTIR spectra, DLS, fluorescence spectroscopy, VSM, and fluorescence microscopy imaging studies. The size range of the end product CLMNPs-tetrapeptide-FA copolymers was from 150 to 190 nm under simulated physiological environment. In vivo, the experimental results of magnetic accumulation showed that the copolymers could be trapped in the tumor tissue under magnetic guidance. Under the present experimental conditions, the loading efficiencies of CPT were approximately 8.6 wt % for CLMNPs-GFFG-FA and 1.1 wt % for CLMNPs-LGPV-FA, respectively. The CPT cumulative release under dialysis condition mainly occurred for the first 28 h, and could reach 55% at pH 5.3 and 46% at pH 7.4 from CPT-loaded CLMNPs-GFFG-FA, and 69% at pH 5.3 and 57% at pH 7.4 from CPT-loaded CLMNPs-LGPV-FA within 28 h, respectively. The hemolysis percentages (<2%) and coagulation properties of blank and CPT-loaded copolymers were within the scope of safe values. Compared to free CPT, the CPT-loaded CLMNPs-tetrapeptide-FA copolymers showed specific targeting to A549 cells in vitro. More than 75% viability in L02 cells were seen in CLMNPs-GFFG-FA and CLMNPs-LGPV-FA copolymer concentration of 500 μg/mL, respectively. It was found that the two kinds of copolymers were transported into the A549 cells by a folate-receptor-mediated endocytosis mechanism. These results indicate that the multifunctional CLMNPs-tetrapeptide-FA copolymers possess a moderate CPT loading efficiency, low cytotoxicity, and favorable biocompatibility, and are promising candidates for tumor-targeted drug delivery.
我们通过原位共轭法制备了一种新型的壳聚糖基荧光/磁性杂化纳米粒子，其具有叶酸偶联四肽复合材料（CLMNPs-tetrapeptide-FA）。首先，壳聚糖、碲化镉量子点（QDs）和超顺磁性氧化铁直接凝胶化成三元杂化纳米凝胶。随后，将四肽（GFFG 和 LGPV）和叶酸有序地共轭到杂化纳米粒子中。使用 TEM、EDX、XRD、FTIR 光谱、DLS、荧光光谱、VSM 和荧光显微镜成像研究对所制备的共聚物的形态、组成和性质进行了表征和确定。在模拟生理环境下，最终产物 CLMNPs-tetrapeptide-FA 共聚物的粒径范围为 150-190nm。在体内，磁性积累的实验结果表明，共聚物可以在磁场引导下被困在肿瘤组织中。在当前实验条件下，CPT 的载药量分别约为 CLMNPs-GFFG-FA 的 8.6wt%和 CLMNPs-LGPV-FA 的 1.1wt%。在透析条件下，CPT 的累积释放主要发生在前 28h，CPT 负载的 CLMNPs-GFFG-FA 可达到 55%（pH5.3）和 46%（pH7.4），CPT 负载的 CLMNPs-LGPV-FA 可达到 69%（pH5.3）和 57%（pH7.4），在 28h 内。空白和 CPT 负载共聚物的溶血率（<2%）和凝血性能均在安全范围内。与游离 CPT 相比，CPT 负载的 CLMNPs-tetrapeptide-FA 共聚物在体外对 A549 细胞具有特异性靶向性。在 CLMNPs-GFFG-FA 和 CLMNPs-LGPV-FA 共聚物浓度为 500μg/mL 时，L02 细胞的存活率均超过 75%。发现这两种共聚物通过叶酸受体介导的内吞作用机制被转运到 A549 细胞中。这些结果表明，多功能 CLMNPs-tetrapeptide-FA 共聚物具有适中的 CPT 载药效率、低细胞毒性和良好的生物相容性，是肿瘤靶向药物输送的有前途的候选物。
