title: Tailoring degradation of AZ31 alloy by surface pre-treatment and electrospun PCL fibrous coating.
abstract: AZ31 magnesium alloy was coated with polycaprolactone (PCL) nano-fibrous layer using electrospinning technique so as to control degradation in physiological environment. Before coating, the alloy was treated with HNO3 to have good adhesion between the coating and substrate. To elucidate the role of pre-treatment and coating, samples only with PCL coating as well as HNO3 treatment only were prepared for comparison. Best coating adhesion of 4B grade by ASTM D3359-09 tape test was observed for pre-treated samples. The effect of coating on in vitro degradation and biomineralization was studied using supersaturated simulated body fluid (SBF 5×). The weight loss and corrosion results obtained by immersion test showed that the combination of HNO3 pre-treatment and PCL coating is very effective in controlling the degradation rate and improving bioactivity. Cytotoxicity studies using L6 cells showed that PCL coated sample has better cell adhesion and proliferation compared to uncoated samples. Nano-fibrous PCL coating combined with prior acid treatment seems to be a promising method to tailor degradation rate with enhanced bioactivity of Mg alloys.
authors.affiliation: Medical Materials Laboratory, Indian Institute of Technology Madras, Chennai 600036, India; School of Nano Science and Technology, National Institute of Technology Calicut, Calicut, Kerala 673601, India.
authors.forename: T
authors.initials: T
authors.lastname: Hanas
authors.affiliation: Medical Materials Laboratory, Indian Institute of Technology Madras, Chennai 600036, India. Electronic address: tssk@iitm.ac.in.
authors.forename: T S
authors.initials: TS
authors.lastname: Sampath Kumar
authors.affiliation: Department of Biotechnology - Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India.
authors.forename: Govindaraj
authors.initials: G
authors.lastname: Perumal
authors.affiliation: Department of Biotechnology - Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India.
authors.forename: Mukesh
authors.initials: M
authors.lastname: Doble
mesh_terms: D000497:Alloys / Q000737:chemistry*; D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D020099:Coated Materials, Biocompatible / Q000737:chemistry* / Q000633:toxicity; D003343:Corrosion; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D017942:Nitric Acid / Q000737:chemistry; D011091:Polyesters / Q000737:chemistry*; D051381:Rats; D013052:Spectrometry, X-Ray Emission; D013499:Surface Properties
chemical_list: D000497:Alloys; D020099:Coated Materials, Biocompatible; C586533:Mg-Al-Zn-Mn-Si-Cu alloy; D011091:Polyesters; C016240:polycaprolactone; D017942:Nitric Acid
keywords: AZ31 magnesium alloy; Acid pre-treatment; Biodegradation; Biomineralization; Electrospinning; Polycaprolactone