Biocompatibility of surfactant‐templated polyurea–nanoencapsulated macroporous silica aerogels with plasma platelets and endothelial cells

Abstract

The recently synthesized polyurea-nanoencapsulated surfactant-templated aerogels (X-aerogels) are porous materials with significantly improved mechanical strengths. Surface-wise they resemble polyurethane, a common biocompatible material, but their biocompatibility has never been investigated. As lightweight and strong materials, if X-aerogels also have acceptable biocompatibility, they may be used in many implantable devices. The goal of this study was to investigate their biocompatibility toward platelets, blood plasma, and vascular endothelial cells, in terms of cell activation and inflammatory responses. Platelets were incubated with X-aerogel and platelet activation was measured through CD62P and phosphatidylserine expression. Platelet aggregation was also measured. Contact with X-aerogel did not induce platelet activation or impair aggregation. To determine X-aerogel-induced inflammation, plasma anaphylatoxin C3a level was measured after incubation with X-aerogel. Results showed that X-aerogel induced no changes in plasma C3a levels. SEM and SDS-PAGE were used to examine cellular/protein deposition on X-aerogel samples after plasma incubation. No structural change or organic deposition was detected. Furthermore, X-aerogel samples did not induce any significant changes in vascular endothelial cell culture parameters after 5 days of incubation. These observations suggest that X-aerogels have a suitable biocompatibility toward platelets, plasma, and vascular endothelial cells, and they have potential for use in blood implantable devices.

Synthesis and biomedical applications of aerogels: Possibilities and challenges

“…It has been revealed that the X-MP4-T045 had constant biocompatibility and structural plasma bio-stability, which is demonstrating its high potential in blood implantable devices [195]. Hemolysis was not affected neither by type of aerogels nor by the physical properties.…”

“…But exploring biocompatibility on silica and other aerogel types are still the matter of contest and, recent works are attempting to address the viability of silica and other composite aerogels in correlation with their mechanical and physical properties such as (density, surface area, porosity and pore volumes) [193][194][195]. The works on the aerogels have…”

“…To surpass the problem of conventional implants, W. Yin et al [194,195] have investigated several formulations of mechanically improved aerogel for implant purposes.…”

“…Recent studies have aimed to address the biocompatibility of various aerogels with different cell types, such as chitosan-silica hybrid aerogel with red blood cells [196], wollastonite aerogels with simulated body fluids [53], polyurea cross-linked silica aerogel [195] and N3300 A polyurea aerogels [194] toward vascular endothelial cells, red blood cells, and plasma platelets. Recently, Rubestein et al [50] have studied the basic biocompatibility of series of aerogels out of poly benzoxazine (PBO), PBO-RF co-polymer and their carbon species from the pyrolysis process.…”

Biomaterials Obtained by Gelation

“…Ambient pressure-dried aerogels (porosity 50 vol %), in which shrinkage during drying was avoided by addition of appropriate surfactants, were made in the system SiO 2 (from tetramethoxysilane: TMOS)-Pluronic P123 ® . They showed a good biocompatibility with plasma proteins, platelets, and vascular endothelial cells, as they did not activate the formation of blood clots, and their use as valves' components in heart surgery is considered (Yin et al 2010;Yin and Rubenstein 2011). Translucent SiO 2 -polyurea aerogels were made by hydrolysis of TMOS, cross-linked to polyurea with APTES, and drying in supercritical CO 2 .…”