Attachment of hyaluronan to metallic surfaces

Abstract

Metal implants are in general not compatible with the tissues of the human body, and in particular, blood exhibits a severe hemostatic response. Herein we present results of a technique to mask the surface of metals with a natural biopolymer, hyaluronan (HA). HA has minimal adverse interactions with blood and other tissues, but attachment of bioactive peptides can promote specific biological interactions. In this study, stainless steel was cleaned and then surface-modified by covalent attachment of an epoxy silane. The epoxy was subsequently converted to an aldehyde functional group and reacted with hyaluronan through an adipic dihydrazide linkage, thus covalently immobilizing the HA onto the steel surface. Fluorescent labeling of the HA showed that the surface had a fairly uniform covering of HA. When human platelet rich plasma was placed on the HA-coated surface, there was no observable adhesion of platelets. HA derivatized with a peptide containing the RGD peptide sequence was also bound to the stainless steel. The RGD-containing peptide was bioactive as exemplified by the attachment and spreading of platelets on this surface. Furthermore, when the RGD peptide was replaced with the nonsense RDG sequence, minimal adhesion of platelets was observed. This type of controlled biological activity on a metal surface has potential for modulating cell growth and cellular interactions with metallic implants, such as vascular stents, orthopedic implants, heart valve cages, and more.

Structural stability and bioapplicability assessment of hyaluronic acid–chitosan polyelectrolyte multilayers on titanium substrates

“…20,21 HA, on the other hand, is a naturally occurring linear anionic polysaccharide present in advanced living organisms, with excellent lubricity, nonadhesive nature, and bacterial inhibitory effect. 22 It has been reported in an earlier work that a HA/ CH functionalized multilayer (with 10 bilayers deposited) on glass gave $80% reduction in the number of adherent E. coli. 23 Thierry et al reported that the HA/CH functionalized alloyed nickel-titanium (Ni-Ti) disks display good hemocompatibility with 38% reduction in platelet adhesion compared to unmodified Ni-Ti disks and a minimum of four bilayers were necessary to mask the metal substrate from its environment.…”

Surface functionalization of titanium with hyaluronic acid/chitosan polyelectrolyte multilayers and RGD for promoting osteoblast functions and inhibiting bacterial adhesion

“…Chitosan (CH) is a polycationic polysaccharide whose antibacterial properties [16,17] and osteoblast function-enhancing nature [18,19] have received substantial interest. Hyaluronic acid (HA), on the other hand, is a polyanionic polysaccharide present in advanced living organisms with excellent lubricity, non-adhesive nature and bacterial inhibitory effect [20]. Richert et al showed that HA/CH PEMs deposited with 10 bilayers on glass offered w80% reduction in the number of adherent Escherichia coli bacteria [21].…”

Quantitative spatial distribution of sirolimus and polymers in drug‐eluting stents using confocal Raman microscopy

“…Fluorescence microscopy was used to describe the uniformity of hyaluronan layers on stainless steel stents. 31 Fluorescence imaging was also useful to describe drug delivery in vitro and in vivo.…”