Plasma‐Assisted Surface Modification and Heparin Immobilization: Dual‐Functionalized Blood‐Contacting Biomaterials with Improved Hemocompatibility and Antibacterial Features

Abstract

The inferior hemocompatibility or antibacterial properties of blood‐contacting materials and devices are restraining factors that hinder their successful clinical utilization. To highlight these, a plasma‐enhanced modification strategy is favored for surface tailoring of an extensively used biomaterial, polypropylene (PP). The surface activation of the PPs is achieved by oxygen plasma etching and subsequent surface functionalization through amine‐rich precursor mediated coating by plasma glow discharge. After optimum plasma processing parameters are decided, heparin (anticoagulant and antithrombic drug) is either attached or covalently conjugated on the PPs’ surfaces. The aminated films produced at 75 W plasma power with 15 min exposure time are highly hydrophilic (34.72 ± 5.92°) and surface active (65.91 mJ m−2), facilitating high capacity heparin immobilization (≈440 µg cm−2) by covalent linkage. The kinetic‐blood coagulation rate and protein adhesion amount on the plasma‐mediated heparinized PPs are decreased about tenfold and 15‐fold, and platelet adhesion is markedly lowered. In addition, heparinized‐PP surfaces comprise superior antibacterial activity against gram‐positive/‐negative bacteria conveyed particularly by contact‐killing (99%). The heparin‐coating did not cause cytotoxicity on fibroblast cells, instead enhanced their proliferation, as shown by the (3‐(4,5‐Dimethylthiazol‐2‐yl)‐2,5‐Diphenyltetrazolium Bromide) assay. Overall, this simple methodology is highly proficient in becoming a universal strategy for developing dual‐functionalized blood‐contacting materials.

Challenge of material haemocompatibility for microfluidic blood-contacting applications

“…Therefore it is often used in combination with other haemocompatible coatings. The free radicals on the material surface after plasma treatment can be reacted with other molecules to cover the surface ( Sharma et al, 2007 ; Shakeri et al, 2019 ; Özgüzar et al, 2022 ). Since plasma treatment is already a crucial step in microfluidic device fabrication, it positions this as a convenient and accessible option for surface pre-treatment.…”

“…This adds further challenge to the method by which heparin can be attached to a substrate. Heparin has been immobilised on polymer surfaces by different methods, requiring initial activation or surface functionalisation which includes polymer brush spacers, protein layers or amination ( Magoshi and Matsuda, 2002 ; Michanetzis et al, 2003 ; Olander et al, 2003 ; Chen et al, 2005 ; Linhardt et al, 2008 ; Du et al, 2011 ; Kolar et al, 2015 ; Biran and Pond, 2017 ; Özgüzar et al, 2022 ). These will be covered in the following sections.…”

Long-term antifouling surfaces for urinary catheters

“…A series of experiments were conducted to determine the antifouling features of the P60-coated urinary catheters (UCs) and uncoated UCs against two Gram-negative bacterial strains: Proteus mirabilis (ATCC 15146) and Escherichia coli (ATCC 25922) using procedure described elsewhere. 39 Specifically, P. mirabilis and E. coli strains were incubated in a tryptic soy broth (TSB) medium, and 10 μl of bacteria cells (1.5 × 10 6 CFU ml −1 ) were inoculated on both uncoated UC and P60-coated UC surfaces and then they were covered with an acetate film to limit evaporation of the medium. All samples were incubated with each bacterial strain for 1, 3, 7 and 30 days at 37 °C (∼15% humidity).…”

Expanding the Scope of an Amphoteric Condensed Tannin, Tanfloc, for Antibacterial Coatings

“…Combining polyanionic GAGs with polycationic TAN can modulate the properties of biomaterials [6]. HEP, a highly negatively charged polymer, inhibits blood coagulation by preventing thrombin activation, making it a valuable component in blood-contacting biomaterials [36,37]. Combining the cationic tannin derivative TAN with HEP in PEMs results in a significant decrease in factor XII activation, platelet adhesion, and activation, enhancing blood compatibility and antibacterial properties on titanium surfaces [38].…”