Advanced drug delivery applications of layered double hydroxide.

Layered double hydroxides (LDHs), also known as anionic clays or hydrotalcite-like compounds, are a class of nanomaterials that attained great attention as a carrier for drug delivery applications. The lamellar structure of this compound exhibits a high surface-to-volume ratio which enables the intercalation of therapeutic agents and releases them at the target site, thereby reducing the adverse effect. Moreover, the intercalated drug can be released in a sustained manner, and hence the frequency of drug administration can be decreased. The co-precipitation, ion exchange, manual grinding, and sol-gel methods are the most employed for their synthesis. The unique properties like the ease of synthesis, low cost, high biocompatibility, and low toxicity render them suitable for biomedical applications. This review presents the advances in the structure, properties, method of preparation, types, functionalization, and drug delivery applications of LDH. Also, this review provides various new conceptual insights that can form the basis for new research questions related to the drug delivery applications of LDH.