Preparation Methods and Functional Characteristics of Regenerated Keratin-Based Biofilms

Abstract

The recycling, development, and application of keratin-containing waste (e.g., hair, wool, feather, and so on) provide an important means to address related environmental pollution and energy shortage issues. The extraction of keratin and the development of keratin-based functional materials are key to solving keratin-containing waste pollution. Keratin-based biofilms are gaining substantial interest due to their excellent characteristics, such as good biocompatibility, high biodegradability, appropriate adsorption, and rich renewable sources, among others. At present, keratin-based biofilms are a good option for various applications, and the development of keratin-based biofilms from keratin-containing waste is considered crucial for sustainable development. In this paper, in order to achieve clean production while maintaining the functional characteristics of natural keratin as much as possible, four important keratin extraction methods—thermal hydrolysis, ultrasonic technology, eco-friendly solvent system, and microbial decomposition—are described, and the characteristics of these four extraction methods are analysed. Next, methods for the preparation of keratin-based biofilms are introduced, including solvent casting, electrospinning, template self-assembly, freeze-drying, and soft lithography methods. Then, the functional properties and application prospects of keratin-based biofilms are discussed. Finally, future research directions related to keratin-based biofilms are proposed. Overall, it can be concluded that the high-value conversion of keratin-containing waste into regenerated keratin-based biofilms has great importance for sustainable development and is highly suggested due to their great potential for use in biomedical materials, optoelectronic devices, and metal ion detection applications. It is hoped that this paper can provide some basic information for the development and application of keratin-based biofilms.

Biodegradable Cellulose/Polycaprolactone/Keratin/Calcium Carbonate Mulch Films Prepared in Imidazolium-Based Ionic Liquid

“…The degraded keratin can serve as a source of nitrogen, sulfur, and carbon for soil microorganisms and can be used as a fertilizer for plant growth. However, to improve the mechanical properties to those required by agricultural mulch film, a biodegradable polymer or inorganic particles must still be used for the preparation of keratin-based biocomposites [ 36 ]. In the field of agriculture, GCC is also used as a fertilizer to supply calcium to plants and to stabilize the pH value, thereby reducing acidic conditions in the soil, in our case from pH 4–5 to pH 5–6 after the biodegradation of the samples.…”

Emergence of integrated biosensing-enabled digital healthcare devices

“…Table 5 details the biocompatibilities of some sensor technologies, as well as their functionality and applications. 129–158 Biocompatible materials for living cells, bone, biological fluid, yak hair, cellular loading, membrane systems for biomedical and electronics purposes have already studied. 129–136 Functionalities related to cytotoxic, DNA binding, photocatalytic, H 2 O 2 detection, antioxidant, transcutaneous measurement, eye-movement tracking, physiological conditions, mitochondria sensors for metabolic state, nanocomposites, gas permeability, DNA methylation, and cancer sensing are important research areas for healthcare devices.…”

“…129–158 Biocompatible materials for living cells, bone, biological fluid, yak hair, cellular loading, membrane systems for biomedical and electronics purposes have already studied. 129–136 Functionalities related to cytotoxic, DNA binding, photocatalytic, H 2 O 2 detection, antioxidant, transcutaneous measurement, eye-movement tracking, physiological conditions, mitochondria sensors for metabolic state, nanocomposites, gas permeability, DNA methylation, and cancer sensing are important research areas for healthcare devices. 137–145 Applications include carboxymethylcellulose (CMC) optical fibers, silicon carbide sensors, smartphone-based colorimetric biosensors, molecularly imprinted sensors, flexible sensors, piezoelectric ceramics sensors, gas sensing, AI-based sensing, pattern recognition sensor arrays, BioMEMS sensor, electro-immunosensing, strain monitoring, and thermal biosensing application for biomedical healthcare.…”

“…Recently developed biosensing platforms offering both the biocompatibility of sensor materials and technologies as well as a variety of functions are discussed. Various sensor technologies' biocompatibility, functionality, and applications 96–106,129–158 are outlined in Fig. 7.…”

Feathered Innovation: Transforming Recycled Keratin into Bioactive Micro/Nanoparticles for Advanced Drug Delivery Systems

“…This has been studied in the context of hydrogel preparation for cosmetic and biomedical applications [23]. The complexation is based on the ionic interaction between the amide networks of keratin and alginate, leading to the formation of dual crosslinked bres [24].…”