The influence of functional groups of self‐assembled monolayers on fibrous capsule formation and cell recruitment

Abstract

The contribution of the surface chemistry of an implant to the thickness of the fibrous capsule formed after implantation was herein investigated. For that, self-assembled monolayers (SAMs) of alkanethiols on gold with different terminal functional groups (COOH, OH, and CH(3)) were used. These surfaces were implanted in subcutaneous air pouches of BALB/c mice and the ensuing fibrous capsules were evaluated and compared with the initial inflammatory response caused by the implant. The thickness of the fibrous capsules that are under organization around the implant was measured 1 week after implantation by histology. Inflammatory exudates were collected from the air pouches 24 h after the implantation of SAMs and were analyzed by flow cytometry. A significant increase in the thickness of fibrous capsules was seen around implanted CH(3)-terminated SAMs, and also in gold surfaces, in comparison with the air pouch wall of sham-operated mice and of COOH- and OH-covered SAMs. The CH(3)-coated implants also recruited higher numbers of inflammatory cells; this enhancement involved a significant number of Mac-1(+) cells. Our data indicate that implant surfaces coated with CH(3) induce thick fibrous capsules and this may be the result of the stronger inflammatory effect of CH(3) in comparison with COOH or OH chemical groups.

A silicone-based microfluidic chip grafted with carboxyl functionalized hyperbranched polyglycerols for selective protein capture

“…A slight increase in the water contact angle for HPG-P3-grafted surface compared to HPG-P2 may due to the presence of more amount of less hydrophilic carboxyl groups connected via ester on HPG-P3. This observation is supported by the reports by Barbosa et al (2005) and Martin et al (2003) that the water contact angles of surfaces grafted with OH terminal polymers were lower than the corresponding COOH terminal polymer. The difference between HPG-P1 and HPG-P2 is due the difference in the molecular weight of the polymer.…”

Adsorbed fibrinogen leads to improved bone regeneration and correlates with differences in the systemic immune response

“…The inflammatory response to implantable devices is greatly influenced by the material surface chemistry, as demonstrated previously by others [5] and us [6][7][8][9]. Using self-assembled monolayers (SAMs) we demonstrated that methyl-terminated SAMs cause early inflammatory cell recruitment in vivo [8], more polymorphonuclear leukocytes (PMNs) than mononuclear cells [9] and the formation of thicker fibrous capsules around implanted materials [6].…”

Surface chemistry influences cancer killing effect of TiO2 nanoparticles

“…Surface functionality has been shown to affect cell:particle interactions [22]. Although it has been suggested that surface functionality should be the determining factor concerning cell uptake and subsequent activity inside the cell [46], studies that have varied surface functionality to investigate membrane binding, uptake, and internalization of nanoparticles are limited.…”

“…As previously noted, the available literature on this subject shows some conflicting results. Since a significant body of recent literature documents the fact that surface functionality affects the interactions between particles and cells [21][22], we have undertaken a comprehensive study to examine the effects of varying surface functional groups on TiO 2 :cell interactions under non-photolytic conditions. For this study, TiO 2 nanoparticles having different surface chemistries were produced.…”