Activated carbon (AC) is an effective adsorbent for creatinine removal in hemoperfusion. However, the hemocompatibility and adsorption capacity of AC was required to be improved furthermore. Heparin, a widely used anticoagulant biomacromolecule, could improve the hemocompatibility of the absorbents in different ways based on its molecular weight. Thus, it was necessary to study the surface modification with unfractionated heparin (UFH) or low molecular weight heparin (LMWH) on improvement of hemocompatibility and adsorption. In this study, UFH and LMWH were respectively grafted on AC through polyethyleneimine as an intermediate layer. The modification of AC about morphology, mechanical strength and pore structure was characterized by XPS, SEM, TA and BET. It was found that compared with AC, the morphology and mechanical strength AC-UFH and AC-LMWH could be well maintained, but the BET surface was decreased due to the grafting of macromolecules. Furthermore, AC-UFH and AC-LMWH showed the better hemocompatibility on protein adsorption, APTT and platelet activation compared with AC, in which AC-LMWH had lower fibrinogen adsorption and longer APTT than AC-UFH. Besides, it was found that AC, AC-UFH and AC-LMWH had no significant effect on blood cell composition. Finally, the adsorption capacity of adsorbents for creatinine was evaluated. Although there was no significant difference between AC-UFH and AC-LMWH, it was found that heparin could be interacted with creatinine to enhance the adsorption capacity when compared with AC-PEI. This study deepened the understanding of anticoagulation of heparinized surface and provided a theoretical basis for adsorbents in hemoperfusion.

Cardiovascular diseases continuing to be a major contributor to illness and death on a global scale and the implementation of stents has given rise to a revolutionary transformation in the field of interventional cardiology. The thrombotic and restenosis complications associated with stent implantation pose ongoing challenges. In recent years, bioactive coatings have emerged as a promising strategy to enhance stent hemocompatibility and reduce thrombogenicity. This review article provides an overview of the surface engineering techniques employed to improve the hemocompatibility of stents and reduce thrombus formation. It explores the mechanisms underlying thrombosis and discusses the factors influencing platelet activation and fibrin formation on stent surfaces. Various bioactive coatings, including anticoagulant agents, antiplatelet agents, and surface modifications, are discussed in detail, highlighting their potential in reducing thrombogenicity. Evaluation methods for assessing hemocompatibility and thrombogenicity are also reviewed, ranging from in vitro assays to animal models. Recent advances in the field, such as nanotechnology-based coatings and bioactive coatings with controlled drug release systems, are highlighted. Surface engineering of bioactive coatings holds great promise for enhancing the long-term outcomes of stent implantation by enhancing hemocompatibility and reducing thrombogenicity. Future research directions and potential clinical applications are discussed, underscoring the need for continued advancements in this field.

Modifying surface topography to prevent surface-induced thrombosis in cardiovascular implants allows endothelialization, which is the natural thrombo-resistance of the blood-contacting surfaces and is deemed to be the only long-term hemocompatible material. We have adapted a simulation framework to predict platelet deposition on the modified surface and developed an optimization strategy to promote endothelial retention and limit platelet deposition. Under supraphysiological bulk shear stress, a maximum of 79% linear coverage was achieved. This study concludes that the addition of microtrenches promotes endothelial retention and can be improved through optimal selection of geometric parameters.

Background: Combinatorial therapy- “nano antibiotics” is an emerging field in nanoscience. In this present investigation, we attempted to combine the green synthesized noble metal nanoparticle and the antibiotic Streptomycin to form bio-conjugated nanoparticles. The newly synthesized Nano antibiotics acted as the antibiotic carrier, functioned as cargo, and delivered the antibiotic. Methods: Comparative studies between the noble metal nanoparticles were attempted for the first time on the grounds of their antibacterial activity. The antibacterial activity of the three noble metal nanoparticles was assessed against Streptomycin-resistant Bacillus sp.; the results obtained proved that silver nanoparticles were a potent antibacterial agent. Still, no antibacterial activity was exerted by gold, and platinum nanoparticles were for the Streptomycin-resistant strain Bacillus sp. To our surprise, the gold and platinum fabricated/bio-conjugated nanoparticle with the antibiotic showed 100% antibacterial activity, whose antibacterial activity was zero when functioning as a nanoparticle alone. Results: The combinatorial therapy of two different clauses of drugs majorly increased antibacterial activity. It enhanced the antibiotic to overcome the resistance exhibited by the bacterial pathogen, and the possible mechanism is elucidated in the present study. Also, an attempt has been made to assess the nanotoxicity of the nano-bioconjugates on RBC and compare their hemocompatibility. The results obtained in the current investigation demonstrate the enhanced antibacterial activity of the green synthesized nanoparticles conjugated with the streptomycin; their efficacy for combinational therapy against resistance in pathogenic organisms highlights the novelty of the work and the comparative study of three different noble metals nanoparticles (Ag, Au, Pt) from single agro-waste for the first time.

(1) Background: The evaluation of ventricular assist devices requires the usage of biocompatible and chemically stable materials. The commonly used polyurethanes are characterized by versatile properties making them well suited for heart prostheses applications but simultaneously they show low stability in biological environment. (2) Methods: An innovative material - copolymer of poly(ethylene-terephthalate) and dimer linoleic acid - with controlled and reproducible physico-mechanical and biological properties was developed for medical applications. Biocompatibility (cytotoxicity, surface thrombogenicity, hemolysis and biodegradation) were evaluated. All results were compared to medical grade polyurethane currently used in the extracorporeal heart prostheses. (3) Results: No cytotoxicity was observed and no significant decrease of cells density as well as no cells growth reduction was noticed. Thrombogenicity analysis showed that the investigated copolymers have the thrombogenicity potential similar to medical grade polyurethane. No hemolysis was observed (the hemolytic index was under 2% according to ASTM 756-00 standard). These new materials revealed excellent chemical stability in simulated body fluid during 180 days ageing. (4) Conclusions: The biodegradation analysis showed no changes in chemical structure, molecular weight distribution, good thermal stability and no changes in surface morphology. Investigated copolymers revealed excellent biocompatibility and great potential as materials for blood contacting devices.