Drug Delivery Systems Based on Hydroxyethyl Starch

Abstract

The advantageous biological properties of hydroxyethyl starch (HES) triggered research interest toward the design and synthesis of drug delivery systems (DDSs) based on this polysaccharide. Convenient reaction schemes, including one-step reactions, led to the synthesis of HES conjugates with selected anticancer molecules or therapeutic proteins. Nanocapsules and hydrogels based on HES were also prepared and studied as prospective drug delivery systems. Formulations originating from these drug conjugates and also from nanocapsules and hydrogels loaded with drugs were characterized, highlighting the extension of their half-life in plasma, which is a critical property as far as their efficacy is concerned. Results obtained in vitro and in vivo proved promising, justifying the undertaking of additional experiments with such systems, including their multifunctionalization. The promising formulations that are discussed in this Topical Review is expected to further increase interest in applying HES for molecular constructing novel DDSs with enhanced efficacy, which may, in the future, find clinical applications.

Chlorin e6‐embedded starch nanogels for improved photodynamic tumor ablation

“…Nevertheless, starch, one of the polysaccharides, can be sophisticatedly engineered using its unique physicochemical properties such as water‐swollen nano‐scale network consisting of water‐insoluble macromolecular sugar chains. The water‐swollen space of starch‐based hydrogel has the potential of drug encapsulation and drug delivery …”

“…The water-swollen space of starch-based hydrogel has the potential of drug encapsulation and drug delivery. 6,10,11 Photodynamic therapy (PDT) has expedited tumor-targeted drug delivery system using the strong absorbance feature of drug carriers in the near-infrared range. In particular, photosensitizers, such as chlorin e6 (Ce6), have been applied to transfer photo-energy to the surrounding oxygen molecules, making singlet oxygen ( 1 O 2 ) for PDT.…”

Colloidal hydroxyethyl starch for tumor-targeted platinum delivery

“…42 A good manufacturing practice, high water solubility, tailorability, biocompatibility, biodegradability, and well-dened and proven in vivo safety features not only facilitate HES to be widely applied in clinics as PVE, 36,[43][44][45] cryoprotectant, [46][47][48][49] organ preservation solutions, 50 granulocytes separation solutions, [51][52][53] and cell culture medium, 54 but also to be a promising drug carrier with promising clinical translation potential. [55][56][57] To this end, various drug delivery systems have been recently developed based on HES, including HES and small drug conjugates; [27][28][29][30]32,34,58 HES and protein conjugates; 56,59 HES-derived nanocolloidosomes; 60 and HES-based nanoparticles, [61][62][63][64][65][66][67] capsules, [68][69][70][71] and hydrogels. [72][73][74][75] Although HES has been applied in clinics for over 50 years, its fundamental conformation, structure, and morphology are largely unknown.…”

Nanosized Delivery Systems for Therapeutic Proteins: Clinically Validated Technologies and Advanced Development Strategies

“…Hydroxyethyl starch (HES) is a biodegradable FDA approved polymer, whose non-immunogenicity is possibly attributed to structural similarities with glycogen (Paleos et al, 2017). HES is degraded by α-amylase in the plasma, which can be controlled by modifying the molar mass and the degree of hydroxyethylation.…”