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To introduce recent research and development of biopolymer deposition for freeform fabrication of three‐dimensional tissue scaffolds that is capable of depositing bioactive ingredients.

A multi‐nozzle biopolymer deposition system is developed, which is capable of extruding biopolymer solutions and living cells for freeform construction of 3D tissue scaffolds. The deposition process is biocompatible and occurs at room temperature and low pressures to reduce damage to cells. In contrast with other systems, this system is capable of, simultaneously with scaffold construction, depositing controlled amount of cells, growth factors, or other bioactive compounds with precise spatial position to form complex cell‐seeded tissue constructs. The examples shown are based on sodium alginate solutions and poly‐ε‐caprolactone (PCL). Studies of the biopolymer deposition feasibility, structural formability, and different material deposition through a multi‐nozzle heterogeneous system are conducted and presented.

Provides information about the biopolymer deposition using different nozzle systems, the relations of process parameters on deposition flow rate and scaffold structural formability. Three‐dimensional alginate‐based scaffolds and scaffold embedded with living cells can be freeform constructed according to various design configurations at room temperature without using toxic materials.

Other biopolymers may also be studied for structure formation. Studying cell viability and cellular tissue engineering behavior of the scaffolds after the cell deposition should be further investigated.

A very useful and effective tool for construction of bioactive scaffolds for tissue engineering applications based on a multi‐nozzle biopolymer deposition.

This paper describes a novel process and manufacturing system for fabrication of bioactive tissue scaffolds, automatic cell loading, and heterogeneous tissue constructs for emerging regenerative medicine.

The purpose of this paper is to acquaint the readers with recent developments in biopolymer-based food packaging materials like natural biopolymers (such as starches and proteins), synthetic biopolymers (such as poly lactic acid), biopolymer blending and nanocomposites grounded on natural and synthetic biopolymers. This paper is an attempt to draw the readers towards the advantages and attributes of new era polymers to diminish the usage of traditional non-biodegradable polymers.

Plastic packaging for food and associated applications is non-biodegradable and uses up valuable and treasured non-renewable petroleum products. With the current focus on researching alternatives to petroleum, research is progressively being channelized towards the development of biodegradable food packaging, thereby reducing adverse impact on the environment.

Natural biopolymer-based nanocomposite packaging materials seem to have a scintillating future for a broad range of applications in the food industry, including advanced active food packaging with biofunctional attributes. The present review summarizes the scientific information of various packaging materials along with their attributes, applications and the methods for production.

This is an apropos review as there has been a recent renewed concern in research studies, both in the industry and academe, for development of new generation biopolymer-based food packaging materials, with possible applications in many areas.

The increasing accumulation of synthetic plastic waste in oceans and landfills, along with the depletion of non-renewable fossil-based resources, has sparked environmental concerns and prompted the search for environmentally friendly alternatives. Biodegradable plastics derived from lignocellulosic materials are emerging as substitutes for synthetic plastics, offering significant potential to reduce landfill stress and minimise environmental impacts. This study highlights a sustainable and cost-effective solution by utilising agricultural residues and invasive plant materials as carbon substrates for the production of biopolymers, particularly polyhydroxybutyrate (PHB), through microbiological processes. Locally sourced residual materials were preferred to reduce transportation costs and ensure accessibility. The selection of suitable residue streams was based on various criteria, including strength properties, cellulose content, low ash and lignin content, affordability, non-toxicity, biocompatibility, shelf-life, mechanical and physical properties, short maturation period, antibacterial properties and compatibility with global food security. Life cycle assessments confirm that PHB dramatically lowers CO₂ emissions compared to traditional plastics, while the growing use of lignocellulosic biomass in biopolymeric applications offers renewable and readily available resources. Governments worldwide are increasingly inclined to develop comprehensive bioeconomy policies and specialised bioplastics initiatives, driven by customer acceptability and the rising demand for environmentally friendly solutions. The implications of climate change, price volatility in fossil materials, and the imperative to reduce dependence on fossil resources further contribute to the desirability of biopolymers. The study involves fermentation, turbidity measurements, extraction and purification of PHB, and the manufacturing and testing of composite biopolymers using various physical, mechanical and chemical tests.

Nowadays, application of biopolymers on geotechnical engineering works is booming to avoid the harsh effects on environment by using conventional methods for soil treatment. In this present study, xanthan gum (XG) is used as a biopolymer to improve dispersive properties of the soils because these soils are easily prone to erosion, which may lead to the damage of many hydraulic structures.

In the present study, attempts are made to reduce the dispersive potential and increase the Strength and erosion resistance by treating the soils with various percentages of XG (0.5%, 1%, 1.5% and 2%). To assess the dispersive potential and erosion resistance of soils, tests such as double hydrometer test, pinhole erosion test, crumb test and cylinder dispersion test were conducted. Further tests were expanded for its geotechnical characteristics such as Atterberg’s limits, standard proctor test, unconfined compressive strength test, one-dimensional consolidation for various curing days. Scanning electron microscopy analysis was also carried out to know the microscopic view towards its particle orientation and bindings. Chemical tests such as sodium absorption ratio, total dissolved solids (TDS) and percentage sodium (PS), electronic conductivity and pH tests were also conducted.

The results revealed that there is a reduction in the dispersive potential of XG treated soils for all the combinations. Addition of XG decreased the PS in the soil as a result dispersivity of soil decreased. Strength and erosion resistance of soil increased with the addition of XG and 1% XG was observed to be the optimum percentage for stabilizing these types of soils.

These results will be very much helpful for engineers when they come across with dispersive soils for better handling and management.

The originality of this study was an attempt towards sustainable development by treating dispersive soils with XG and effects on various geotechnical and dispersive characterizes.

The purpose of this paper was to develop an antimicrobial edible film coated with essential oils for packaging application with characterization of its physicochemical properties. Livestock products especially meat products need special packaging system for protection. The most well-known packaging materials are polyethylene or co-polymer-based materials which have led to serious ecological problems due to their non-biodegradability and non-renewable nature. There has been a growing interest for edible films in recent years trying to reduce the amount of wastes, capable of protecting the food once the primary packaging is open, and because of public concerns about environmental protection. Various kinds of antimicrobial substances can also be incorporated into edible films to improve their functionality, as these substances could limit or prevent microbial growth on food surface.

Biopolymers such as carrageenan and carboxymethylcellulose and their various combinations were tried to develop an edible film. The levels of antimicrobial substances such as oregano and thyme essential oils were standardized on the basis of their minimal inhibitory concentration against Escherichia coli, Salmonella pullorum, Staphylococcus aureus and Listeria monocytogenes. Standardized edible film coated with standardized concentration of essential oil was examined for different physicochemical properties and compared with edible film without essential oil.

In total, 1.5 per cent (w/v) solution of carrageenan was found best suited biopolymer for edible film formation on the basis of thickness, transparency and elongation ability. Combined concentration of oregano (0.02 per cent) and thyme (0.03 per cent) essential oils were found to be best suited for coating the edible film as antimicrobial application.

Future research may benefit from the present attempt in evaluating the potency of easily available agricultural by produces for preparation of economically viable edible film incorporated with various natural biopreservatives in combination for the enhancement of shelf life.

Antimicrobial packaging for enhancing the quality and shelf life of stored meat products offers great scope for further research in this field. Moreover, the literature pertaining to the application of edible films containing biopreservative for chicken meat products is very limited.

This study aims to restore the lost mechanical properties of the prints with carrageenan, methyl hydroxyethyl cellulose (Tylose) and hydroxypropyl methylcellulose (Methocel).

The effect of these materials on the properties of the printed paper (modern and historical samples) has been evaluated under the influence of accelerated aging using pH measurement, the mechanical properties (tensile and elongation), FTIR and color changes.

The three consolidates reduced the acidity of treated samples significantly, but after ageing, it was observed that the pH of aged treated samples decreased slightly as compared to the untreated samples. The results of the mechanical properties showed the superiority of hydroxypropyl methylcellulose (Methocel) in improving the tensile and elongation forces of the samples compared to carrageenan and methyl hydroxyethyl cellulose even during the accelerated aging. Consolidation materials succeeded in reducing ΔE of the paper samples under accelerated aging, especially carrageenan. The IR spectra confirmed that no dramatic difference was observed in topically function vibrations of samples after treatment beside that the O-H stretching band intensity increased observably after treatment with the three consolidates, after ageing the treatment, and it protected the treated paper from oxidation processes as the infrared spectrum analysis showed a decrease in intensities of carbonyl and carboxyl groups as compared to aged untreated samples.

The research provides new biopolymers in strengthening the historical printed paper, where printed papers lack studies related to their conservation. This makes the current study a promising step for treating historical printed paper.

The complications caused by metallic orthopaedic bone screws like stress-shielding effect, screw loosening, screw migration, higher density difference, painful reoperation and revision surgery for screw extraction can be overcome with the bioabsorbable bone screws. This study aims to use additive manufacturing (AM) technology to fabricate orthopaedic biodegradable cortical screws to reduce the bone-screw-related-complications.

The fused filament fabrication technology (FFFT)-based AM technique is used to fabricate orthopaedic cortical screws. The influence of various process parameters like infill pattern, infill percentage, layer height, wall thickness and different biological solutions were observed on the compressive strength and degradation behaviour of cortical screws.

The porous lattice structures in cortical screws using the rapid prototyping technique were found to be better as porous screws can enhance bone growth and accelerate the osseointegration process with sufficient mechanical strength. The compressive strength and degradation rate of the screw is highly dependent on process parameters used during the fabrication of the screw. The compressive strength of screw is inversely proportional to the degradation rate of the cortical screw.

The present study is focused on cortical screws. Further different orthopaedic screws can be modified with the use of different rapid prototyping techniques.

The use of rapid prototyping techniques for patient-specific bone screw designs is scantly reported. This study uses FFFT-based AM technique to fabricate various infill patterns and porosity of cortical screws to enhance the design of orthopaedic cortical screws.

The purpose of this study is to develop active package films using clove essential oil (CEO) and biodegradable polybutylene adipate terephthalate (PBAT) with varying weight percentages of SiO₂ nanoparticles (SiO₂NPs), as well as to investigate the mechanical, barrier, thermal, optical, surface hydrophobicity and antibacterial properties of PBAT incorporated with CEO as a natural plasticizer and SiO₂NPs as a nanofiller.

PBAT-based bio-composites films were fabricated with different weight percentage of CEO (5% and 10%) and nanosilica (1% and 3%) by solution casting method. The packaging performance was investigated using universal testing machine, spectrophotometer, contact angle goniometer, oxygen and water vapour permeability tester. The antibacterial properties of PBAT-based nanocomposite and composite films were investigated using the ISO 22196 by zone of inhibition method.

The mechanical results exhibited that the addition of 10 Wt.% of CEO into PBAT increases the percentage of elongation, whereas, the addition of 3 Wt.% of SiO2NPs increases the tensile strength of the composite film. The presence of CEO in PBAT exhibits a good barrier against water permeability and SiO2NPs in the PBAT matrix help to reduce the opacity and hydrophobicity. The antimicrobial and thermal results revealed that the inclusion of 10 Wt.% of CEO and 3 Wt.% of SiO₂NPs into PBAT polymer improved antimicrobial and thermal resistance properties.

A new PBAT-based active packaging film developed using natural plasticizers CEO and nanofiller SiO₂ with a wide range of applications in the active food packaging applications. Moreover, they have good surface hydrophobicity, thermal stability, mechanical, barrier and antibacterial properties.

Tissue engineering (TE) involves biological, medical and engineering expertise and a current engineering challenge is to provide good TE scaffolds. These highly porous 3D scaffolds primarily serve as temporal holding devices for cells that facilitate structural and functional tissue unit formation of the newly transplanted cells. One method used successfully to produce scaffolds is that of rapid prototyping. Selective laser sintering (SLS) is one such versatile method that is able to process many types of polymeric materials and good stability of its products. The purpose of this paper is to present modeling of the heat transfer process, to understand the sintering phenomena that are experienced by powder particles in the SLS powder bed during the sintering process. With the understanding of sintering process obtained through the theoretical modeling, experimental process of biomaterials in SLS could be directed towards the appropriate sintering window, so as not to cause unintentional degradation to the biomaterials.

SLS uses a laser as a heat source to sinter parts. A theoretical study based on heat transfer phenomena during SLS process was carried out. The study identified the significant biomaterial and laser beam properties that were critical to the sintering result. The material properties were thermal conductivity, thermal diffusivity, surface reflectivity and absorption coefficient.

The influential laser beam properties were laser power and scan speed, which were machine parameters that can be controlled by users. The identification of the important parameters has ensured that favorable sintering conditions can be achieved.

The selection of biopolymer influences the manner in which energy is absorbed by the powder bed during the SLS process. In this paper, the modeling and investigative work was validated by poly(vinyl alcohol) which is a biomaterial that has been used for many biomedical and pharmaceutical purposes.

The paper can be the foundation for extension to other types of biomaterials including biopolymers, bioceramics and biocomposites.

The formulation of the theory for heat transfer phenomena during the SLS process is of significant value to any studies in using SLS for biomedical applications.

This study aims to discuss the impact of using bio-polymer (kraft lignin) in the formulation of passenger vehicle disc brake pads (as a substitute for cashew nutshell liquid [CNSL]-based friction dust) and investigate the characteristics of the pads.

Within the scope of this investigation, three different brake pads were generated by altering the biopolymer-lignin content in conjunction with the friction dust from CNSL without modifying the other components. The brake pads were created in accordance with industry-standard practices. Industrial standards were used to evaluate the newly created brake pad’s thermal, physical and mechanical qualities. The tribological properties of the materials were determined using a full-scale inertia brake dynamometer. The scanning electron microscope examined the worn surfaces in conjunction with elemental mapping.

The test findings suggest that the brake pads filled with biopolymer-lignin and CNSL-based friction dust (as a partial replacement 50%) exhibited excellent thermal, physical, mechanical characteristics, as well as steady friction and low wear rate.

A bio-polymer (kraft lignin) in friction composites has the potential to produce eco-friendly brake pads and improve the tribological performance of its copper free-composition, which might be used to replace CNSL-based friction dust in friction composites by addressing the issues raised in this work.