Design of thermoresponsive hydrogels by controlling the chemistry and imprinting of drug molecules within the hydrogel for enhanced loading and smart delivery of drugs

• Published in: Molecular systems design & engineering 2021-04, Vol.6 (4), p.286-292
• Main Authors: Park, Sang-Yu, Kim, Seong Yeol, Kang, Ji-Hye, Kim, Han-Sem, Shin, Ueon Sang
• Format: Article
• Language: English
• Subjects: Chemical compounds; Doxorubicin; Hydrogels; Lewis acid; Molecular imprinting; Morphology; Pharmacology; Temperature dependence
• ISSN: 2058-9689; 2058-9689
• DOI: 10.1039/d0me00097c

Various drug delivery techniques have contributed significantly to medical practice. In particular, molecular imprinting is a suitable method to increase the drug-loading efficiency in limited 3D spaces, such as hydrogels. This method has recently been studied for the transdermal delivery of various therapeutic agents, but its full potential is yet to be achieved in molecular systems. In this study, thermoresponsive and molecularly imprinted hydrogels were prepared by radical polymerization with molecular imprinting using three types of drug molecules as templates. The drug templates-acyclovir (ACV), diclofenac (DFN), and doxorubicin (DXR)-were used to establish molecular correlations between molecularly imprinted hydrogels and drug molecules by using non-covalent Lewis acid-base interactions, hydrophilicity and molecular size. The DXR-imprinted hydrogel exhibited a much greater imprinting efficiency than ACV- and DFN-imprinted hydrogels because of the hydrophilic characteristics and large molecular size of DXR compared with the other drugs. The morphology, surface area, and swelling behavior, dependent on the temperature, were also investigated. The in vitro drug release studies performed at various temperatures revealed unique drug release profiles unlike previous thermoresponsive studies. This study demonstrated a facile strategy to construct molecularly imprinted hydrogels that exhibit thermoresponsive delivery and offer new guidelines to identify optimal combination between drugs and hydrogels. Thermoresponsive and molecularly imprinted hydrogels were synthesized by radical polymerization with molecular imprinting using three types of drug templates.