The optimization and production of stable homogeneous amine enriched surfaces with characterized nanotopographical properties for enhanced osteoinduction of mesenchymal stem cells

Abstract

Silane modification has been proposed as a powerful biomaterial surface modification tool. This is the first comprehensive investigation into the effect of silane chain length on the resultant properties of -NH silane monolayers and the associated osteoinductive properties of the surface. A range of -NH presenting silanes, chain length 3-11, were introduced to glass coverslips and characterized using water contact angles, atomic force microscopy, X-ray photoelectron spectroscopy, and Ninhydrin assays. The ability of the variation in chain length to form a homogenous layer across the entirety of the surfaces was also assessed. The osteoinductive potential of the resultant surfaces was evaluated by real-time polymerase chain reaction, immunocytochemistry, and von Kossa staining. Control of surface chemistry and topography was directly associated with changes in chain length. This resulted in the identification of a specific, chain length 11 (CL11) which significantly increased the osteoinductive properties of the modified materials. Only CL11 surfaces had a highly regular nano-topography/roughness which resulted in the formation of an appetite-like layer on the surface that induced a significantly enhanced osteoinductive response (increased expression of osteocalcin, CBFA1, sclerostin, and the production of a calcified matrix) across the entirety of the surface. © 2018 The Authors Journal of Biomedical Materials Research Part A Published by Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1862-1877, 2018.

A New Approach for Glyco-Functionalization of Collagen-Based Biomaterials

“…In Samples 3 and 4, a slight increase in the ranges of carbohydrate moiety between 1000–1200 cm −1 is noticeable, in particular the typical peak of glucose at 1040 cm −1 [13]. Ninhydrin assay has been also performed in the first step to have a fast qualitative method to characterize the success in the insertion of keton groups on the collagen surface (Figure 2B) [14].…”

Cost effective optimised synthetic surface modification strategies for enhanced control of neuronal cell differentiation and supporting neuronal and Schwann cell viability

“…Glass coverslips (13mm 2 ) were modified with 3% aminosilanes (SC: 3‐aminopropyl triethoxysilane; LC: 11‐aminoundecyltriethoxysilane) as previously described 10 . Briefly, glass coverslips were cleaned using a 0.5 M solution of sodium hydroxide and then 1 M Nitric acid for 30 min in an ultrasonic bath, followed by washing in three changes of distilled water, and dried in a 50°C oven.…”

“…We have previously reported that 11‐aminoundecyltriethoxysilane surfaces supported osteogenic differentiation of mesenchymal stem cells, in contrast to 3‐aminopropyl triethoxysilane 10 . Aminosilanes, of varying chain lengths, were fully characterised, using water contact angle, X‐ray photoelectron spectroscopy (XPS) and atomc force microscopy, to determine the effect of silane chain length on surface chemistry and topography at sub‐micron level.…”

“…Aminosilanes, of varying chain lengths, were fully characterised, using water contact angle, X‐ray photoelectron spectroscopy (XPS) and atomc force microscopy, to determine the effect of silane chain length on surface chemistry and topography at sub‐micron level. 11‐aminoundecyltriethoxysilane modified surfaces presented an ordered nanoroughness, resulting in favorable 'surface chemistry and topography' for osteoinduction, but has not been investigated for other tissue engineering applications 10 …”

“…However, silane chain length has not been investigated thoroughly for nerve implant biomaterials. The aim of the present study was to investigate the influence of two different silane chain lengths, with known surface chemistry and topography, characterised from our previous study, 10 on neuronal and Schwann cell differentiation and phenotype.…”