7-Ethyl-10-hydroxycamptothecin (SN-38) as a potent anti-tumor candidate, suffers the constraints from its poor water solubility, pH-dependent lactone ring stability and the lack of efficient delivery system without losing its activity. Herein, biocompatible superparamagnetic chitosan-based nanocomplexes complexing with water-soluble polymeric prodrug poly(L-glutamic acid)-SN-38 (PGA-SN-38) was engineered for efficient delivery of SN-38. The manufacturing process of colloidal complexes was green, expeditious and facile, with one-shot addition of PGA-SN-38 into chitosan solution without using any organic solvent or surfactant. Upon introducing ultra-small-size superparamagnetic nanoparticles (~10 nm), the developed magnetic nanocomplexes exhibited significantly boosted tumor-targeted accumulation and efficient cellular internalization under a local magnetic field. Notably, the magnetic nanocomplexes achieved distinctly superior targeting and anti-tumor efficacy in the established xenograft colorectal cancer model of mice, with high tumor suppression rate up to 81%. Therefore, this superparamagnetic chitosan-based nanocomplex system could provide a promising platform for the targeted delivery of SN-38 in colorectal cancer therapy.

7-Ethyl-10-hydroxycamptothecin (SN-38) 作为一种有效的抗肿瘤候选药物，受到水溶性差、pH 依赖性内酯环稳定性和缺乏有效递送系统而不会失去其活性的限制。在此，生物相容性超顺磁性壳聚糖基纳米复合物与水溶性聚合物前药聚（L-谷氨酸）-SN-38 (PGA-SN-38) 复合，可有效递送 SN-38。胶体配合物的制备工艺绿色、快捷、简便，无需使用任何有机溶剂或表面活性剂，将PGA-SN-38一次性加入壳聚糖溶液中。在引入超小尺寸超顺磁性纳米粒子（~10 nm）后，开发的磁性纳米复合物在局部磁场下表现出显着增强的肿瘤靶向积累和有效的细胞内化。值得注意的是，磁性纳米复合物在已建立的小鼠异种移植结直肠癌模型中实现了明显优越的靶向性和抗肿瘤功效，肿瘤抑制率高达81%。因此，这种基于超顺磁性壳聚糖的纳米复合物系统可以为 SN-38 在结直肠癌治疗中的靶向递送提供一个有前景的平台。