本研究的目的是开发用于乳腺癌治疗的生物素化壳聚糖（Bio-Chi）修饰的多壁碳纳米管（MWCNTs），以结合酪氨酸激酶抑制剂奈瑞铂（NT）。为实现这一目的，我们首先将羧酸功能化的多壁碳纳米管（c-MWCNTs）经过非共价交联修饰上生物素壳聚糖（Bio-Chi）涂层，以实现双重靶向模式；其中使用壳聚糖实现酸性pH条件下的释放，使用生物素实现生物素受体介导的主动靶向。随后，使用Bio-Chi修饰的c-MWCNTs载入酪氨酸激酶抑制剂奈瑞铂（NT）。然后，通过动态光散射、傅里叶红外光谱和能量散射光谱对该制剂进行表征。药物装载效率估计为95.6 ± 1.2%。体外药物释放研究表明，Bio-Chi修饰的c-MWCNTs对NT的释放具有pH依赖性，在酸性pH条件下药物释放更多。不同NT制剂的SRB细胞毒性实验显示，对SkBr3细胞系的毒性呈剂量依赖性，与自由NT或裸露的NT载药的c-MWCNTs相比，NT载药的Bio-Chi涂层c-MWCNTs显示出更强的细胞毒性。自由NT、NT载药的c-MWCNTs和NT载药的Bio-Chi涂层c-MWCNTs的IC50值分别为548.43 ± 23.1 μg mL-1、319.55 ± 17.9 μg mL-1和257.75 ± 24.5 μg mL-1。有趣的是，竞争性细胞摄取研究显示，将载药的c-MWCNTs表面修饰为Bio-Chi能增强乳腺癌细胞对c-MWCNTs的摄取，可能是通过生物素受体介导的内吞作用。总之，Bio-Chi修饰的c-MWCNTs可能是一种有前景的递送工具，可用于乳腺癌细胞的细胞特异性药物输送。

The aim of this study was to develop biotinylated chitosan (Bio-Chi) decorated multi-walled carbon nanotubes (MWCNTs) for breast cancer therapy with the tyrosine kinase inhibitor, neratinib (NT). For achieving such a purpose, carboxylic acid functionalized multiwalled carbon nanotubes (c-MWCNTs) were initially decorated non-covalently with biotin-chitosan (Bio-Chi) coating for achieving a dual targeting mode; pH-dependent release with chitosan and biotin-receptor mediated active targeting with biotin. Afterwards, Bio-Chi decorated c-MWCNTs were loaded with the tyrosine kinase inhibitor, neratinib (NT). The formulation was then characterized by dynamic light scattering, FTIR and EDX. The drug loading efficiency was estimated to be 95.6 ± 1.2%. In vitro drug release studies revealed a pH-dependent release of NT from Bio-Chi decorated c-MWCNTs, with a higher drug release under acidic pH conditions. Sulforhodamine B (SRB) cytotoxicity assay of different NT formulations disclosed dose-dependent cytotoxicities against SkBr3 cell line, with a superior cytotoxicity observed with NT-loaded Bio-Chi-coated c-MWCNTs, compared to either free NT or NT-loaded naked c-MWCNTs. The IC50 values for free NT, NT-loaded c-MWCNTs and NT-loaded Bio-Chi-coated c-MWCNTs were 548.43 ± 23.1 μg mL-1, 319.55 ± 17.9 μg mL-1, and 257.75 ± 24.5 μg mL-1, respectively. Interestingly, competitive cellular uptake studies revealed that surface decoration of drug-loaded c-MWCNTs with Bio-Chi permitted an enhanced uptake of c-MWCNTs by breast cancer cells, presumably, via biotin receptors-mediated endocytosis. To sum up, Bio-Chi-decorated c-MWCNTs might be a promising delivery vehicle for mediating cell-specific drug delivery to breast cancer cells.This journal is © The Royal Society of Chemistry.