A Review on Plant Cellulose Nanofibre-Based Aerogels for Biomedical Applications

Abstract

Cellulose nanomaterials from plant fibre provide various potential applications (i.e., biomedical, automotive, packaging, etc.). The biomedical application of nanocellulose isolated from plant fibre, which is a carbohydrate-based source, is very viable in the 21st century. The essential characteristics of plant fibre-based nanocellulose, which include its molecular, tensile and mechanical properties, as well as its biodegradability potential, have been widely explored for functional materials in the preparation of aerogel. Plant cellulose nano fibre (CNF)-based aerogels are novel functional materials that have attracted remarkable interest. In recent years, CNF aerogel has been extensively used in the biomedical field due to its biocompatibility, renewability and biodegradability. The effective surface area of CNFs influences broad applications in biological and medical studies such as sustainable antibiotic delivery for wound healing, the preparation of scaffolds for tissue cultures, the development of drug delivery systems, biosensing and an antimicrobial film for wound healing. Many researchers have a growing interest in using CNF-based aerogels in the mentioned applications. The application of cellulose-based materials is widely reported in the literature. However, only a few studies discuss the potential of cellulose nanofibre aerogel in detail. The potential applications of CNF aerogel include composites, organic-inorganic hybrids, gels, foams, aerogels/xerogels, coatings and nano-paper, bioactive and wound dressing materials and bioconversion. The potential applications of CNF have rarely been a subject of extensive review. Thus, extensive studies to develop materials with cheaper and better properties, high prospects and effectiveness for many applications are the focus of the present work. The present review focuses on the evolution of aerogels via characterisation studies on the isolation of CNF-based aerogels. The study concludes with a description of the potential and challenges of developing sustainable materials for biomedical applications.

Keywords: aerogel; biomedical applications; cellulose; nanofibre; sustainable.

Figure 1

Cellulose nanofibre (CNF)-based aerogel in biomedical applications.

Figure 2

The number of scientific publications contributing to the subject “cellulose nanofibre; CNF and aerogel” by year (search done through ScienceDirect on 6 June 2020 (from 2009 to 2019).

Figure 3

Schematic drawing of plant cellulosic fibre hierarchical structure. (1) Bark cambium pith, (2) cambium (3) mature cell wall, (4) cellulose fibre, and (5) chemical structure of cellulose (cited from H.P.S. Abdul Khalil et al. [50]). Copyright 2016. Reused with permission from Elsevier Ltd.

Figure 4

Illustration of plant cell wall and structure of native plant cellulosic fibre (adapted from Journal of Saudi Chemical Society; Mishra [54]. Copyright 2018. Reused with permission from Elsevier Ltd.

Figure 5

Steps of plant cellulose nanofibre (CNF) isolation from lignocellulose biomass.

Figure 6

Steps of preparation of aerogel from a precursor solution.

Figure 7

Schematic diagram of the use of CNF in tissue engineering (adapted from Tingli Lu et al. [115]. Copyright 2013. Reproduced with permission from the Dove Medical Press publisher.

Figure 8

Schematic drawing of production of biodegradable antimicrobial wound dressing material (adapted from T. Hakkarainen [119] et al., 2016). Copyright 2016. Reproduced with permission from Elsevier Ltd.

Figure 9

Schematic diagram of the potential use of CNF aerogel in the diagnosis of specific antigens.

Figure 10

Fabrication process of drug delivery aerogel (cited from García-González et al. [122]. Copyright 2011. Reproduced with permission from Elsevier Ltd.