Surface Modifications of the Biodegradable Magnesium Based Implants with Self-Assembled Monolayers Formed by T-BAG Method

Abstract

In this paper, magnesium based materials (Mg and Mg-alloy (AZ91D)) were surface modified using various organic acids (carboxylic and phosphonic), in order to improve corrosion resistance and enhance theirs biocompatibility. Formations of surface layer were performed by tethering by aggregation and growth (T-BAG) method. Organization and bond mode of these layers were examined by Fourier transform infrared spectroscopy (FTIR). Additionally, semiempirical quantum molecular modeling calculation methods were used for getting insight into their structural and electronic properties, as also as corrosion resistance in the physiological solution (Hanks' solution). Corrosion resistance of modified materials were investigated by electrochemical impedance spectroscopy (EIS) in the physiological solution (Hanks' solution) and obtained results reveal a beneficial effect of the modification by forming organic acids self-assembled monolayer (SAM) on the corrosion properties of magnesium based materials, especially layers of octadecylphosphonic acid. The maximum corrosion inhibition efficiency of 87% for magnesium and of 93% for Mg-alloy (AZ91D) are achieved by the formation of octadecylphosphonic acid (ODPA) SAM.

Corrosion protection of tin by some carboxylic acids in sodium chloride solution

“…From the above data, it is also evident that as the length of the hydrocarbon chain increases, the capacitive semicircle, i.e. the polarization resistance of the tin electrode, increases [6]. Thus, the largest numerical value of PE equal to 87 % was obtained for the Sn electrode coated with a SA film formed after ten cycles of the dip-coating/drying procedure.…”

“…In the FTIR spectra, the peaks at 2852 cm -1 and 2922 cm -1 assigned to symmetric (2852 cm -1 ) and asymmetric (2922 cm -1 ) C-H stretching vibrations, respectively, indicate that SA has been successfully adsorbed [26]. Peaks at ~1540 cm -1 are attributed to the stretching vibration of carboxyl groups (-COO -) [6,27,28]. In the FTIR spectra of a tin plate on which SA was applied by the dipcoating method, the C-O stretching band occurs at 1464 cm -1 while the band at 1413 cm -1 is related to stretching vibrations of the C-O-H bond [29].…”

“…The environmental toxicity of organic corrosion inhibitors has prompted the search for green corrosion inhibitors since they are biodegradable and do not contain heavy metals or other toxic compounds [1]. Metal protection vis these organic inhibitors comes from the fact that they adsorb on the metal surface to form a protective layer against corrosive species in the media [4][5][6]. The efficiency of an inhibitor depends on many factors, such as the nature of the metal surface, the type of corrosive media and the chemical structure of the inhibitor.…”

Znanstveno-istraživačka djelatnost Zavoda za opću i anorgansku kemiju u razdoblju 2010. – 2020.

“…Jedna od metoda kojom je pomoću različitih organskih kiselina (karboksilnih i fosfonskih) modificirana površina materijala na bazi magnezija (Mg i Mg-legura (AZ91D)) bilo je vezivanje metodom agregacije i rasta (T-BAG). U radu Škugor Rončević et al 17 karakterizirani su kovalentno vezani SAM-ovi organskih kiselina formirani na nativnoj (na zraku spontano pasiviranoj) površini Mg i Mg legure (AZ91D). Također su, za dobivanje uvida u strukturna i elektronska svojstva zaštitnog filma, primijenjene metode kvantno molekularnog modeliranja (poluempirijskog izračuna).…”

Synthesis and Study of Catalytic, Anti–Bacterial, Anti–Oxidant, and DNA Cleavage Properties of Ag–Co and Ag–Ni Magnetic Nanoparticles

“…Binary or multi-metal alloys have attracted growing research interest in recent years in both industrial and laboratory chemical processes due to their unique and novel optical, electrical, and catalytic properties. [1][2][3][4] Alloying two or more metals can improve the mechanical, chemical, electrical, and thermal conductivity properties of pure metals. 5 Among metallic alloys, nanoalloys are gaining increasing importance and have several advantages over their corresponding bulk forms.…”