Recent advance in preparation of lignin nanoparticles and their medical applications: A review

Lignin has attracted a lot of attention because it is non–toxic, renewable and biodegradable. Lignin nanoparticles (LNPs) have high specific surface area and specific surface charges. It provides LNPs with good antibacterial and antioxidant properties. LNPs preparation has become clear, however, the application remains in the early stages. A review centric research has been conducted, reviewing existing literature to accomplish a basic understanding of the medical applications of LNPs. Initially, we extensively counseled the heterogeneity of lignin from various sources. The size and morphology of LNPs from different preparation process were then discussed. Subsequently, we focused on the potential medical applications of LNPs, including drug delivery, wound healing, tissue engineering, and antibacterial agents. Lastly, we explained the significance of LNPs in terms of antibacterial, antioxidant and biocompatibility, especially highlighting the need for an integrated framework to understand a diverse range of medical applications of LNPs. We outlined the chemical structure of different type of lignin, and highlighted the advanced methods for lignin nanoparticles preparation. Moreover, we provided an in–depth review of the potential applications of lignin nanoparticles in various medical fields, especially in drug carriers, wound dressings, tissue engineering components, and antimicrobial agents. This review provides a detailed overview on the current state and progression of lignin nanoparticles for medical applications.