Biological response of endothelial cells to diamond‐like carbon‐coated NiTi alloy

Abstract

Diamond-like carbon (DLC) coatings were deposited on nearly equiatomic nickel-titanium (NiTi) alloy by arc-enhanced magnetron sputtering. The microstructure, surface morphology, chemical composition, surface free energy, protein adsorbance, and leach amount of Ni ions were assessed by Raman spectroscopy, high-resolution transmission electron microscopy (HR-TEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), contact angle measurements, micro BCA™ protein assay kit, and inductively coupled plasma mass spectrometry (ICP-MS). The biological response of the endothelial cells (ECs) was evaluated by cell adhesion, morphology, viability, and expression levels of thrombogenicity-related genes. Our results show that the DLC coatings inhibit the release of Ni ions from the NiTi substrate effectively thus enhancing its biosafety. The easy adhesion, elongated morphology, and high viability of ECs on the DLC coatings suggest fast endothelialization after implantation and so application of DLC coatings improves the surface properties of NiTi in cardiovascular applications. The relationship between the surface characteristics, Ni leaching, and concomitant biological response are discussed in details.

Dihydroartemisinin inhibits multiplication of Brucella suis vaccine strain 2 in murine microglia BV2 cells via stimulation of caspase‑dependent apoptosis

“…In brief, cells (1×10 4 ) were seeded in 96-well culture plates and cultured overnight. The cells were treated with different concentrations of DHA (0, 10, 20, 40 and 80 µM) for 24 h, and the CCK-8 solution was added to each well and incubated for an additional 4 h. The absorbance at 450 nm was measured by Microplate reader (BioTek Instruments, Inc.) (13).…”

Overview on the Antimicrobial Activity and Biocompatibility of Sputtered Carbon-Based Coatings

“…DLC coatings deposited on an equiatomic nickel-titanium (NiTi) alloy inhibited the release of Ni ions from the NiTi substrate, enhancing its biosafety. The adhesion, morphology, and viability of endothelial cells (ECs) showed to be better on DLC coatings than on bare NiTi alloy, leading to faster endothelialization after surgical implantation [184]. Mononuclear macrophages (THP-1 monocytes) cell proliferation revealed no significant promotion between TiN coated and uncoated stainless steel; however, pro-inflammatory TNF-α levels were found to be higher, indicating better biocompatibility [185].…”

Nano-Modified Titanium Implant Materials: A Way Toward Improved Antibacterial Properties

“…Lack of nickel can cause diabetes, uremia, kidney failure, and other diseases. Studies have shown that Ni 2+ can effectively kill bacteria ( Yasuyuki et al, 2010 ), but excessive Ni 2+ will cause cytotoxicity ( Lü et al, 2009 ; Hang et al, 2012 ). A recent study showed that Ni 2+ released from NiTi alloys could exhibit antibacterial properties ( Ohtsu et al, 2017 ).…”