Article

Starch Phosphate Microgels for Controlled Release of Biomacromolecules

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Abstract

Gel-forming starch phosphates with a content of acidic phosphate groups ranging from 2.1 to 3.8 mmol/g were obtained in a phosphoric acid-urea system. The rates of starch phosphate degradation in buffer solution in the absence of amylase and in the presence of this enzyme were investigated in vitro. Starch phosphate gels were shown to be prone to enzymatic degradation. However, the rate of biodegradation decreased gradually as the content of phosphate groups increased. The use of microgels with average particle sizes in the range of 7.8–60.1 μm for the production of controlled-release preparations of interferon-alpha 2b has been demonstrated to be possible in principle.

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... The study reported that the novel microgels successfully sustained the release of sodium benzoate and zosteric acid for up to 72 and 120 h, respectively [56]. Yurkshtovich et al. demonstrated the ability of starch phosphate microgels to encapsulate interferon-alpha 2b and aimed to deliver the therapeutic agent for cancer or viral infection treatments [57]. Furthermore, Zhang et al. developed the self-stabilized hyaluronic acid nanogels for the codelivery of doxorubicin and cisplatin to treat osteosarcoma. ...
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