Lignin as a Biomaterial for Bioimaging

Abstract

Applications of lignin-based biomaterials are increasing these days. Their cost-effectiveness and facile synthesis process makes them ideal biomaterials for several branches of science, engineering, and medicine. Their high carbon content, thermal stability, biodegradability, and antioxidant and antimicrobial activity allow them to be used for several applications such as (1) sensors, (2) targeted drug release, and (3) memory materials. Lignin-based biomaterials are less toxic to and are biocompatible with cells. More importantly, they show photoluminescent properties. All these properties make them suitable for biomedical imaging. Biomedical imaging is an obligatory tool for detecting and treating many life-threatening diseases including cancer. Lignin-based biomaterials are used in photodynamic and photothermal therapy. To achieve this, lignin is synthesised with several metal ions or carbon dots using several steps. The achieved lignin-based biomaterials exhibit their fluorescence in the range from 300 nm to 800 nm. The fluorescence properties of lignin allow it to be used in numerous near-infrared applications. This chapter summarises the synthesis and application of lignin-based biomaterials for photodynamic and photothermal therapy.