Alteration of physico-mechanical properties of black tilapia scale gelatins using UVA and UVC irradiation

Fish gelatin is abundant, relatively low cost and biodegradable. However, their inferior mechanical and rheological properties make them less competitive compared to mammalian gelatins. Hence, the effects of Ultraviolet (UV) irradiation on the properties of scale gelatins were analyzed. Gelatins were extracted from black tilapia scale via thermal extraction method. The gelatins were then subjected to Ultraviolet-A (UVA) and Ultraviolet-C (UVC) irradiation for 0.5 to 2.5 h and the changes in gel strength, viscosity, and melting temperature were observed. Results obtained show a marked increase in the gel strength and viscosity of the gelatins. However, the effects on the melting temperature are minimal. Treatment with UVA and UVC improved the gel strength of the gelatins up to 5.12 ± 0.22 N and 4.75 ± 0.09 N, respectively. Further analysis using Fourier Transform Infrared (FTIR) Spectroscopy showed crosslinking formation in the polypeptide chains induced by UV irradiation. UVA was found to be more effective in enhancing the properties of scale gelatins compared to UVC. In general, UV-irradiated scale gelatins showed excellent properties compared to the commercial bovine gelatin. Results indicated the prospects of employing UV treatment in enhancing the properties of fish gelatin

Fabrication of natural and bio-based wound healing material from alginate and beeswax

Alginate is a natural polysaccharide derived from brown algae and exhibits the following properties: biocompatible, biodegradable and non-toxic. Beeswax is a secretion that is produced by young working bees. For this research project, alginate and beeswax are homogenized together to form bio-based films for wound healing applications. Solution casting method was used to fabricate the films of 1 wt% and 2 wt% sodium alginate (SA) with 0-5 g beeswax. The films were then characterized and tested using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM), Atomic Force Microscopy (AFM), and contact angle measurement. FTIR spectra revealed that all films showed spectra from both SA and beeswax pellet, which implies that alginate and beeswax coexist in the film. SEM images showed smooth surfaces for films of 1 wt% and 2 wt% SA with 0 g beeswax and rough surfaces with beeswax particles for films of 1 wt% and 2 wt% SA with 1-5 g beeswax. AFM results revealed that the surface roughness of alginate and beeswax films increased with an increasing amount of beeswax and film of 2 wt% SA with 5 g beeswax recorded the highest surface roughness value. Contact angle measurement revealed that as more beeswax was introduced into alginate solution, the contact angle value increases due to the hydrophobic nature of beeswax. It can be concluded that these alginate and beeswax films can be applied as both hydrophilic and hydrophobic wound dressing material

Alteration of Physico-mechanical Properties of Black Tilapia Scale Gelatins using UVA and UVC Irradiation

Fish gelatin is abundant, relatively low cost and biodegradable. However, their inferior mechanical and rheological properties make them less competitive compared to mammalian gelatins. Hence, the effects of Ultraviolet (UV) irradiation on the properties of scale gelatins were analyzed. Gelatins were extracted from black tilapia scale via thermal extraction method. The gelatins were then subjected to Ultraviolet-A (UVA) and Ultraviolet-C (UVC) irradiation for 0.5 to 2.5 h and the changes in gel strength, viscosity, and melting temperature were observed. Results obtained show a marked increase in the gel strength and viscosity of the gelatins. However, the effects on the melting temperature are minimal. Treatment with UVA and UVC improved the gel strength of the gelatins up to 5.12 ± 0.22 N and 4.75 ± 0.09 N, respectively. Further analysis using Fourier Transform Infrared (FTIR) Spectroscopy showed crosslinking formation in the polypeptide chains induced by UV irradiation. UVA was found to be more effective in enhancing the properties of scale gelatins compared to UVC. In general, UV-irradiated scale gelatins showed excellent properties compared to the commercial bovine gelatin. Results indicated the prospects of employing UV treatment in enhancing the properties of fish gelatin

Effect of UV wavelength on apatite formation of anodised titanium

A novel method to accelerate the apatite formation on the anodised titanium is proposed in this article. The processing was composed of two steps which were UV light treatment after anodic oxidation, and UV light illumination during soaking in simulated body fluid (SBF). This study aims to investigate the effect of different UV wavelengths during SBF on the apatite formation of anodised titanium. The titanium foils were anodised in mixture of β-glycerophosphate disodium salt pentahydrate (β-GP) and calcium acetate monohydrate (CA). Subsequently, the anodised titanium foils were pre-treated with UV light. In vitro was conducted by illuminating with different wavelengths of UV light (254nm and 365nm) in SBF. Field emission scanning electron microscopy (FESEM) and X-ray diffractometer (XRD) were used to characterise the surface morphology and crystallinity of anodised titanium. The results showed that donut-shaped pores with anatase/rutile phases were formed on the surface of anodised titanium. Apart from that, the UV light treatment did change the chemical properties of anodised titanium by producing more •OH groups. After UV light illumination in SBF for 1 week, the anodised titanium foils were fully covered by bone-like apatit

Comparative study on microencapsulated of natural and waste sunflower oil as self-healing agent

Microencapsulation of natural vegetable oil as a self-healing agent on metal coating became demanded lately. This paper underlines the microcapsule containing natural and wastes sunflower oil as a self-healing agent that was fabricated for the backbone of corrosion coatings. The results in this paper indicated the distinguished potential of waste sunflower oil as compared to natural sunflower oil. The diameter of microcapsules synthesized from natural sunflower oil and waste sunflower oil both in range of 3-4 µm. The shell of microcapsules microencapsulated from natural sunflower oil showed rough micro-structure while the shell of microcapsules microencapsulated from waste sunflower oil showed smooth micro-structure. The main parameter studied in this research was the varient of stirring speed during the process of microencapsulation. The involvement of stirring speed starts from 200 to 400 rpm. The microcapsules undergo varient of stirring speed analyzed on the yield and core content of microcapsules. The microcapsules from natural produced 29-50 % while waste resources bring 26-48 % of yield productions. The core content of microencapsulated natural sunflower oil generates 55-64 % core content as comparing with waste sources which produce 56-67 % of core content. It can be concluded that it was proved that sunflower oil could be considered as an alternative resource for self-healing agent in metal coating either encapsulated from natural or waste raw materials. The incorporation of green and natural material as a self-healing agent significantly influences the sustaining the environment to the safest stage

Sodium alginate-zinc oxide nanocomposite film for antibacterial wound healing applications

This study aims to develop sodium alginate (SA) based ZnO nanoparticles as antibacterial film for wound healing applications. As natural materials, sodium alginate has been widely investigated and used in wound healing. The ZnO nanoparticles were incorporated as antibacterial into sodium alginate with different compositions (2, 4, 6, 8, 10 ml). Solvent casting method was performed to prepare a film. The film was characterized by using Fourier Transform Infrared Spectroscopy (FT-IR), Atomic Force Microscopy (AFM) and Field Emission Scanning Electron Microscopy (FESEM). Effectiveness of antibacterial activity was carried out against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) to characterize the sample. The results from microstructure analysis indicated that as ZnO nanoparticle compositions increased, the film surface became rough. It was found that sodium alginate incorporated with ZnO had slightly higher antibacterial activities against S. aureus than E. coli. Thus, sodium alginate (SA)-Zinc oxide (ZnO) nanoparticle has the potential to be used as a wound healing material in biomedical applications

Effect of GTAW on the Mechanical Properties of Mild Steel

GTAW is considered highly popular in manufacturing. The welding factors such as welding voltage, welding current...etc., play a significant role in determining the welding quality. This study discusses the effect of GTAW factors on the mechanical properties of commercial steel welding. Base metal thickness, welding current and welding speed are factors that will be optimized for maximum tensile strength and hardness using Taguchi’s design. The analysis found that base metal thickness had the highest effect on tensile strength and hardness of the welding, followed by welding current. The welding speed had a lower influence. The optimized combination is the base metal thickness of 10 mm, the welding current of 170A and the welding speed of 100 mm/mi

Polyvinyl alcohol-alginate adsorbent beads for chromium (vi) removal

Chromium pollution has been an increasing concern worldwide because of its high toxicity and carcinogenic properties, and it requires an efficient purification technique. In this study, adsorbent beads containing polyvinyl alcohol (PVA) and sodium alginate were prepared by crosslinking with boric acid and calcium chloride for adsorbent of the hexavalent chromium [Cr (VI)]. Batch adsorption studies were conducted to evaluate Cr (VI) adsorption rates of PVA-alginate beads from aqueous solution under ultraviolet (UV) light illumination. The surface morphology and elemental composition of beads were examined using field emission scanning electron microscopy (FESEM) and energy dispersive spectrometer (EDS), respectively. This study revealed that the Cr (VI) adsorption rates increased remarkably with dosages of PVA and sodium alginate. This occurred mainly due to the increasing number of the active sites for adsorption. The results revealed that adsorbent beads with 12 g of PVA and 2.5 g sodium alginate beads exhibited superior Cr (VI) adsorption efficiency at which it is completely removed after 1.5 hours. The findings of this study indicate that PVA-sodium alginate beads are a viable option for Cr (VI) removal from industrial wastewater

Extraction of natural hydroxyapatite for biomedical applications—a review

Hydroxyapatite has recently played a crucial role in the sustainable development of biomedical applications. Publications related to hydroxyapatite as filler for biopolymers have exhibited an increasing trend due to the expanding research output. Based on the latest publications, the authors reviewed the research trends regarding hydroxyapatite use in biomedical applications. Analysis of the Scopus database using the keywords ‘hydroxy�apatite” and “biomedical applications” determined that 1,714 papers were produced between 2012 and 2021. The number of publications related to these keywords more than doubled between 2012 (99) and 2021 (247). The hydrothermal method, solid-state reactions, the sol-gel process, emulsion, micro-emulsion, and mostly chemical precipitation were used to produce synthetic hydroxyapatite. Meanwhile, calcination, alkaline hydrolysis, pre�cipitation, hydrothermal, and a combination of these techniques were used in producing natural hydroxyapatite. Studies in the current literature reveal that shell-based animal sources have been frequently used as hydroxy�apatite resources during investigations concerning biomedical applications, while calcination was the extraction method most often applied. Essential trace elements of fish bone, oyster shell, and eggshell were also found in hydroxyapatite powder. Abalone mussel shell and eggshell showed Ca/P ratios closer to the stoichiometric ratio due to the use of effective extraction methods such as manipulating aging time or stirring process parameters. This review should greatly assist by offering scientific insights to support all the recommended future research works, not only that associated with biomedical applications

Synthesis and characterisation of hydroxyapatite from Fringescale sardinella for biomedical applications

Hydroxyapatite (HAp) from fish by-product exhibits good biocompatibility and bioactivity on implants. The aim of the study is to investigate the elemental composition, crystalline phases, and functional groups of HAp synthesised from fringescale sardinella fish bones by heat decomposition method at temperature of 600, 900, and 1200 °C. The synthesised powders were characterized using fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and energy dispersive spectroscopy (EDS). After calcination of the raw fish bone to 600, 900, and 1200 °C, the FTIR data showed the existence of phosphate and hydroxyl peaks in the calcined fish bones. At 900 and 1200°C, the XRD data observed shows well-defined peaks of HAp pattern. The elemental composition evaluated by EDS provides information on the calcium to phosphate formation into apatite with a Ca/P ratio of 2.80, 0.98, 1.64 and 1.79 atomic % for raw fish bones and calcined samples, respectively. It can be concluded that the fringescale sardinella fish bones show promising findings particularly on the synthesisation of HAp for biomedical application