Influences of the pH on the adsorption properties of an antimicrobial peptide on titanium surfaces

Abstract

The adsorption behavior of the Tet-124 antimicrobial peptide and the Tet-124peptide modified at the C- and N-terminus with the sequence glycine-3,4-dihydroxyphenylalanine-glycine (G-DOPA-G) on titanium surfaces was studied using quartz crystal micro balance with dissipation (QCM-D). At a low pH level(4.75) Tet-124 and Tet-124-G-DOPA-G form rigid layers. This is attributed to the electrostatic interactions of the positively charged lysine and arginine residues in the peptide sequence with the negatively charged titanium oxide layer. At an elevated pH level (6.9) Tet-124 shows a lower mass adsorption at the surface than Tet-124-G-DOPA-G. This is attributed to the interaction of the catechol due to the formation of complexes with the titanium oxide and titanium surface layer. The C terminal and N terminal modification with the sequence G-DOPA-G shows similar adsorption rate and mass adsorption coverage at saturation; however it is presented a more loosely layers on the G-DOPA-G-TeT-124. Fibroblast adhesion and the biocompatibility test of both the surfaces following modification withTet-124-G-DOPA-G and the titanium alloy control showed similar results. In addition, no changes in the adhesion of E. colibacteria due to the modification of the surface were detected

Functionalization of CoCr surfaces with cell adhesive peptides to promote HUVECs adhesion and proliferation

“…Beneficiaria COLFUTURO 2008 Moreover, the extent of thickness and surface mass density of immobilized peptide onto CoCr sensors was as follows: RGDS (153,42 ng/cm 2 ) > REDV (92,33 ng/cm 2 ) > YIGSR (50,43 ng/cm 2 ) ( Table 2). Such differences may be expected on the basis of distinct electrostatic interactions between the biomolecules and the CoCr sensors surface [52,53]. At physiological pH, REDV and RGDS peptides are negatively charged, but YIGSR total net charge is zero.…”

Implementation of diverse non-centrosymmetric layer concepts for tuning the interface activity of a magnesium alloy

“…Tuning the composition of the gas phase and further optimizing the parameters guiding the energy impact during the laser treatment will contribute to increasing the performance of these layers. In comparison with PECVD or high-energy laser [22] processes the application of liquid formulations by dipping or spraying facilitates a less elaborate or milder surface functionalization, resulting in thinner layers allowing for instance the modification of nanostructured substrates [33,34]. Concerning the approaches based on wet processes, the investigated natural biopolymer mixtures containing laccase and maltodextrin, as well as the synthetic amphiphilic polymers optimized for the application on aluminum alloys [35], showed multi-metal effectivity evidenced by a fast adsorption on AM50 surfaces, resulting in layers with a thickness between 0.001 and 0.01 µm.…”

Functionalization of hydrophobic surfaces with antimicrobial peptides immobilized on a bio-interfactant layer

“…Layer-by-layer deposition is a common physical immobilization technique applied to hydrophilic materials such as metal oxides, mainly due to electrostatic interactions 16,17 or the adding of a specic surface binding recognition sequence to the peptide. [18][19][20] This method may be applied on hydrophobic polymer surfaces aer applying a process to increase the concentration of functional groups such as hydroxyl and carbonyl groups, and next covalent attachment using click chemistry. 21 Another viable method is solid phase peptide synthesis on polymer resins in which the protected amino acids are incorporated by assembling the peptide sequence from its C-to its N-terminus; however, these methods are time consuming and costly.…”