Status and future scope of plant-based green hydrogels in biomedical engineering

Abstract

Hydrogels are the most iconic class of soft materials and since their first report in the literature has attracted the attention of uncountable researchers. Over the past two decades, hydrogels become smart and sophisticated materials with plenty of applications possibilities. The biomedical research area has demonstrated a particular interest in hydrogels since they can be engineered from different polymers and due to their tunable properties. Moreover, hydrogels engineered from polymers extracted from biorenewable sources have been popularized in biomedical usages, as they are low-toxic, eco-friendly, biocompatible, easily accessible, and inexpensive at the same time. However, the multifaceted challenge is to find an ideal plant green hydrogel in the tissue engineering that can mimic critical properties of human tissues in terms of structure, function, and performance. In addition, these natural polymers are also idealized to be conveniently functionalized so that their chemical and physical behaviour can be manipulated for drug delivery and stem cell-guided tissue regeneration. Here, the most recent advances in the synthesis, fabrication and application of plant green hydrogels in biomedical engineering are reviewed. It covers essential and updated information about plant as green sources of biopolymers to be used in hydrogel synthesis, general aspects of hydrogels and plant green hydrogels and a substantive discussion regarding the use of such hydrogels in the biomedical engineering area. Furthermore, this review addresses and detail the present status of the field and, also, answer several important questions about the potential use of plant green hydrogels in advanced biomedical applications including therapeutic, tissue engineering, wound dressing, diagnostic, etc.

In situ forming microporous gelatin methacryloyl hydrogel scaffolds from thermostable microgels for tissue engineering

“…Hydrogels sourced from natural and/or synthetic materials have leveraged technologies pertinent to water treatment, energy storage, food security, and healthcare. [1][2][3][4][5][6][7] Granular hydrogel scaffolds have introduced emerging opportunities for developing in vitro tissue/disease models as well as in vivo therapies in regenerative medicine [8][9][10][11] owing to their unique structural features, particularly interconnected pores that promote cellular infiltration and enhance tissue remodeling. 12,13 The success of such scaffolds relies on their capability to overcome some of the key shortcomings of bulk hydrogels, mainly unconnected nanoscale pores that are 2-3 orders of magnitude smaller than the cell size.…”

“…Hydrogels sourced from natural and/or synthetic materials have leveraged technologies pertinent to water treatment, energy storage, food security, and healthcare 1‐7 . Granular hydrogel scaffolds have introduced emerging opportunities for developing in vitro tissue/disease models as well as in vivo therapies in regenerative medicine 8‐11 owing to their unique structural features, particularly interconnected pores that promote cellular infiltration and enhance tissue remodeling 12,13 .…”

“…photocrosslinking step (exposure time up to 90 s at an intensity of~100 mW/cm 2 and a wavelength of~365 nm) increases the thermostability of GelMA microgels while decreasing their scaffold forming (annealing) capability. Hinging on the tradeoff between microgel and scaffold stabilities, we identify the optimal crosslinking condition (exposure time~60 s) that enables the formation of stable annealed microgel scaffolds.…”

Optimization of Chitosan–Alginate Microparticles for Delivery of Mangostins to the Colon Area Using Box–Behnken Experimental Design

“…Chitosan with amino groups is soluble at low pH and insoluble at high pH. It also has good biocompatibility, biodegradability, and nontoxicity, and it can be readily modified for delivering drugs and bioactive compounds [17][18][19][20][21][22]. Owing to these properties, chitosan is widely used in colon-targeted drug delivery formulations.…”

Self‐Healing Polyester Urethane Supramolecular Elastomers Reinforced with Cellulose Nanocrystals for Biomedical Applications

“…The PEU films indicated a significantly higher weight loss (≈19%) in comparison to the nanocomposites. The percentage of weight loss decreased with increasing CNC content which could be attributed to the non‐ or slow degradability of CNCs as a result of lack of cellulose enzymes in the experimental condition . A sudden decrease in weight was observed at day 1 and thereafter the films were degraded at a very slow rate.…”