Chromium–protein complexation studies by adsorptive cathodic stripping voltammetry and MALDI-TOF–MS

Wang

et al. 2013

J Mater Sci: Mater Med

109

141

Implantation using stainless steels (SS) is an example where an understanding of protein-induced metal release from SS is important when assessing potential toxicological risks. Here, the protein-induced metal release was investigated for austenitic (AISI 304, 310, and 316L), ferritic (AISI 430), and duplex (AISI 2205) grades in a phosphate buffered saline (PBS, pH 7.4) solution containing either bovine serum albumin (BSA) or lysozyme (LSZ). The results show that both BSA and LSZ induce a significant enrichment of chromium in the surface oxide of all stainless steel grades. Both proteins induced an enhanced extent of released iron, chromium, nickel and manganese, very significant in the case of BSA (up to 40-fold increase), whereas both proteins reduced the corrosion resistance of SS, with the reverse situation for iron metal (reduced corrosion rates and reduced metal release in the presence of proteins). A full monolayer coverage is necessary to induce the effects observed.Electronic supplementary materialThe online version of this article (doi:10.1007/s10856-013-4859-8) contains supplementary material, which is available to authorized users.

Section: Resultssupporting

confidence: 41%

Section: Resultsmentioning

confidence: 96%

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Surface-protein interactions on different stainless steel grades: effects of protein adsorption, surface changes and metal release

Wang

et al. 2013

J Mater Sci: Mater Med

109

141

“…The determination limit of the diluted samples in this study was 0.4 µg L −1 Cr(VI). Analytical details are given elsewhere . The exposure conditions (phosphate buffer, pH 7.4, closed vessels with relatively low amounts of dissolved oxygen) are optimal to avoid any transformation of Cr(III) to Cr(VI) and vice versa .…”

Section: Methodsmentioning

confidence: 99%

Metal release and speciation of released chromium from a biomedical CoCrMo alloy into simulated physiologically relevant solutions

Wallinder

2013

J Biomed Mater Res

Self Cite

The objective of this study was to investigate the extent of released Co, Cr(III), Cr(VI), and Mo from a biomedical high-carbon CoCrMo alloy exposed in phosphate-buffered saline (PBS), without and with the addition of 10 µM H2 O2 (PBS + H2 O2 ), and 10 g L(-1) bovine serum albumin (PBS + BSA) for time periods up to 28 days. Comparative studies were made on AISI 316L for the longest time period. No Cr(VI) release was observed for any of the alloys in either PBS or PBS + H2 O2 at open-circuit potential (no applied potential). However, at applied potentials (0.7 V vs. Ag/AgCl), Cr was primarily released as Cr(VI). Co was preferentially released from the CoCrMo alloy at no applied potential. As a consequence, Cr was enriched in the utmost surface oxide reducing the extent of metal release over time. This passivation effect was accelerated in PBS + H2 O2 . As previously reported for 316L, BSA may also enhance metal release from CoCrMo. However, this was not possible to verify due to the precipitation of metal-protein complexes with reduced metal concentrations in solution as a consequence. This was particularly important for Co-BSA complexes after sufficient time and resulted in an underestimation of metals in solution.

“…A Metrohm 797 VA Computrace instrument with a hanging mercury drop working electrode, a Ag/AgCl (saturated KCl) reference electrode, and a platinum auxiliary electrode were used for measurement of samples (2 mL) in the supporting electrolyte (2.5 mL: 0.2 M sodium acetate, 0.05 M diethylenetriaminepentaacetate (DTPA), 2.5 M sodium nitrate) diluted by ultrapure water (8 mL, 18.2 MXcm) to 10.5 mL solution and adjusted to a pH of 6.2 ± 0.1 with 30% ultrapure NaOH. The detailed procedure is described in (Hedberg et al, 2012a).…”

Section: Chromium Speciationmentioning

confidence: 99%

Comparison of the influence of citric acid and acetic acid as simulant for acidic food on the release of alloy constituents from stainless steel AISI 201

Mazinanian

Wallinder

Journal of Food Engineering

2015

a b s t r a c tTo ensure the safety of metals and alloys intended for food contact, a new European test protocol (CoE protocol) using citric acid as a food simulant was published in 2013. This study investigated the influence of citric acid and exposure conditions on the metal release from an austenitic manganese stainless steel (AISI 201). Exposures in 5 g/L citric acid resulted in significantly lower metal releases compared with specific release limits set by the CoE protocol. 5 g/L (0.3 vol%) citric acid was more aggressive than 3 vol% acetic acid (Italian protocol) due to higher metal complexation. Studies on abraded surfaces revealed that most metals were released during the first 0.5 h of exposure due to surface passivation. Surface abrasion, increased temperature (40-100°C), increased surface area to solution volume ratio (0.25-2 cm 2 /mL) and increased citric acid concentration (0-21 g/L) all resulted in increased released metal quantities.