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In this work, corrosion behaviour of zinc-based alloys with addition of 0.5%, 1%, and 2% of zirconium for biodegradable material as orthopaedic implant were investigated. The potentiodynamic polarization method is carried out to determine the corrosion resistance and corrosion rate of each composition in order to observe the effect of zirconium addition in a Kokubo simulated body fluid solution. The result showed that the addition of 0.5% and 1% of zirconium would decrease the corrosion rate of Zn-xZr alloys corresponding to 0.079 mm/year and 0.116 mm/year whereas the 2% addition would increase the rate to 0.188 mm/year due to the formation of Zr-rich precipitates inside the alloys. The passivation zone on the polarization curve showed the formation of the protected thin layer on the surface of the alloys which caused the corrosion rate to decrease, therefore confirmed the degradable ability of the Zn-xZr alloys. In general, the corrosion rates of Zn-xZr alloys were higher than Fe-based alloys and lower than Mg-based alloys. Moreover, the corrosion rates were much lower than the maximum rate of 0.4 mm/year for biodegradable implants so Zn-xZr alloys were suitable as biodegradable material implant for orthopaedic application.

Severe burns need additional collagen to accelerate reepithelization and burns healing process by using wound dressing. However, cow and pig as the major source of collagen Type-I are susceptible to infectious diseases and pig is restricted in some religions. Thus, there is need to find an alternative non-mammal collagen source. Aquatic origin collagen has been persuading as an alternative to mammalian origin. However, low denaturation temperature collagen restricts clinical application. Wound dressing with thermal stability is highly desired for burns healing. The aims of this work were the extraction of collagen Type-I from snakehead fish skin (Channa striata) and crosslinking collagen with alginate. Extraction of collagen consist of pretreatment to remove grease, hydrolysis to remove undesirable protein, and extraction to obtain acid-soluble collagen (ASC) by acetic acid. Biopolymer was synthesized by crosslinking collagen and cross- linking agent, sodium alginate (SA). Optimum concentration of collagen and SA is required. The different concentrations (1, 3, 5%) of SA were dissolved by sodium phosphate buffer. The extracted collagen was characterized using Fourier Transform Infrared Spectroscopy (FTIR) to analyze functional groups. Biopolymer was characterized for functional groups, micrograph, and thermal stability. Results reveal, functional groups Amide A (3414 cm−1), Amide I (1637 cm−1), Amide II (1548 cm−1), Amide III (13338 cm−1) refers to collagen Type-I. ASC was successfully extracted from Channa striata and classified as Type-I collagen. Addition of SA for 3% has the best thermal stability. This finding shows the potential use of this collagen-based biopolymer as a promising new dressing for burn healing.