Mussel-inspired "built-up" surface chemistry for combining nitric oxide catalytic and vascular cell selective properties

Cu(II)-Organic Coordination Polymer Networks for Persistent Nitric Oxide Release in Tumor Therapy

Nitric oxide (NO) plays a key role in regulating the immune system by polarizing macrophages toward the proinflammatory M1 phenotype, which is beneficial for cancer immunotherapy. We developed a Cu-organic coordination polymer network to sustainably release NO from endogenous donors. This robust polymer network was constructed through a dual-interaction process: complexation and cross-linking. The carboxylate groups of deprotonated 4-((6-(acryloyloxy)hexyl)oxy)benzoic acid (BA) served as bidentate ligands for the formation of Cu(II) complexes. The acrylate moiety of BA anchored these complexes in the polymer network, forming a cross-linked film. Cu ions within the network catalytically promoted NO release from S-nitrosoglutathione, maintaining this release even after 90 days in a physiological environment. The released NO effectively polarized both resting (M0) and tumor-promoting (M2) macrophages to the M1 phenotype. With their demonstrated physiological stability and sustained NO release performance, BA-Cu films hold potential as anticancer patches capable of continuously promoting antitumoral macrophages.

Endothelium-Mimicking Materials: A "Rising Star" for Antithrombosis

The advancement of antithrombotic materials has significantly mitigated the thrombosis issue in clinical applications involving various medical implants. Extensive research has been dedicated over the past few decades to developing blood-contacting materials with complete resistance to thrombosis. However, despite these advancements, the risk of thrombosis and other complications persists when these materials are implanted in the human body. Consequently, the modification and enhancement of antithrombotic materials remain pivotal in 21st-century hemocompatibility studies. Previous research indicates that the healthy endothelial cells (ECs) layer is uniquely compatible with blood. Inspired by bionics, scientists have initiated the development of materials that emulate the hemocompatible properties of ECs by replicating their diverse antithrombotic mechanisms. This review elucidates the antithrombotic mechanisms of ECs and examines the endothelium-mimicking materials developed through single, dual-functional and multifunctional strategies, focusing on nitric oxide release, fibrinolytic function, glycosaminoglycan modification, and surface topography modification. These materials have demonstrated outstanding antithrombotic performance. Finally, the review outlines potential future research directions in this dynamic field, aiming to advance the development of antithrombotic materials.

A fucoidan-loaded hydrogel coating for enhancing corrosion resistance, hemocompatibility and endothelial cell growth of magnesium alloy for cardiovascular stents

Although magnesium alloy has received tremendous attention in biodegradable cardiovascular stents, the poor in vivo corrosion resistance and limited endothelialization are still the bottlenecks for its application in cardiovascular stents. Fabrication of the multifunctional bioactive coating with excellent anti-corrosion on the surface is beneficial for rapid re-endothelialization and the normal physiological function recovery of blood vessels. In the present study, a bioactive hydrogel coating was established on the surface of magnesium alloy by copolymerization of sulfobetaine methacrylate (SBMA) and acrylamide (AM) via ultraviolet (UV) polymerization, followed by the immobilization of fucoidan (Fu). The results showed that the as-prepared multifunctional hydrogel coating could enhance the corrosion resistance and the surface wettability of the magnesium alloy surface, endowing it with the ability of selective albumin adsorption; meanwhile, it could augment biocompatibility. The following introduction of fucoidan on the surface could further improve the hemocompatibility characterized by reducing protein adsorption, minimizing hemolysis, and preventing platelet aggregation and activation. Additionally, the immobilized fucoidan promoted endothelial cell (EC) growth, as well as up-regulated the expression of vascular endothelial growth factor (VEGF) and nitric oxide (NO) in endothelial cells (ECs). Consequently, this research paves a novel approach to developing a versatile bioactive coating for magnesium alloy surfaces and lays a foundation in cardiovascular biomaterials.

A CO-releasing coating based on carboxymethyl chitosan-functionalized graphene oxide for improving the anticorrosion and biocompatibility of magnesium alloy stent materials

Due to its biofunctions similar to NO, the CO gas signaling molecule has gradually shown great potential in cardiovascular biomaterials for regulating the in vivo performances after the implantation and has received increasing attention. To construct a bioactive surface with CO-releasing properties on the surface of magnesium-based alloy to augment the anticorrosion and biocompatibility, graphene oxide (GO) was firstly modified using carboxymethyl chitosan (CS), and then CO-releasing molecules (CORM401) were introduced to synthesize a novel biocompatible nanomaterial (GOCS-CO) that can release CO in the physiological environments. The GOCS-CO was further immobilized on the magnesium alloy surface modified by polydopamine coating with Zn2+ (PDA/Zn) to create a bioactive surface capable of releasing CO in the physiological environment. The outcomes showed that the CO-releasing coating can not only significantly enhance the anticorrosion and abate the corrosion degradation rate of the magnesium alloy in a simulated physiological environment, but also endow it with good hydrophilicity and a certain ability to adsorb albumin selectively. Owing to the significant enhancement of anticorrosion and hydrophilicity, coupled with the bioactivity of GOCS, the modified sample not only showed excellent ability to prevent platelet adhesion and activation and reduce hemolysis rate but also can promote endothelial cell (EC) adhesion, proliferation as well as the expression of nitric oxide (NO) and vascular endothelial growth factor (VEGF). In the case of CO release, the hemocompatibility and EC growth behaviors were further significantly improved, suggesting that CO molecules released from the surface can significantly improve the hemocompatibility and EC growth. Consequently, the present study provides a novel surface modification method that can simultaneously augment the anticorrosion and biocompatibility of magnesium-based alloys, which will strongly promote the research and application of CO-releasing bioactive coatings for surface functionalization of cardiovascular biomaterials and devices.

Nitric Oxide Releasing Nanomaterials for Cardiovascular Applications

A central paradigm of cardiovascular homeostasis is that impaired nitric oxide (NO) bioavailability results in a wide array of cardiovascular dysfunction including incompetent endothelium-dependent vasodilatation, thrombosis, vascular inflammation, and proliferation of the intima. Over the course of more than a century, NO donating formulations such as organic nitrates and nitrites have remained a cornerstone of treatment for patients with cardiovascular diseases. These donors primarily produce NO in the circulation and are not targeted to specific (sub)cellular sites of action. However, safe, and therapeutic levels of NO require delivery of the right amount to a precise location at the right time. To achieve these aims, several recent strategies aimed at therapeutically generating or releasing NO in living systems have shown that polymeric and inorganic (silica, gold) nanoparticles and nanoscale metal-organic frameworks could either generate NO endogenously by the catalytic decomposition of endogenous NO substrates or can store and release therapeutically relevant amounts of NO gas. NO-releasing nanomaterials have been developed for vascular implants (such as stents and grafts) to target atherosclerosis, hypertension, myocardial ischemia-reperfusion injury, and cardiac tissue engineering. In this review, we discuss the advances in design and development of novel NO-releasing nanomaterials for cardiovascular therapeutics and critically examine the therapeutic potential of these nanoplatforms to modulate cellular metabolism, to regulate vascular tone, inhibit platelet aggregation, and limit proliferation of vascular smooth muscle with minimal toxic effects.

Nanotexture and crystal phase regulation for synergistic enhancement in re-endothelialization on medical pure titanium surface

Re-endothelialization has been recognized as a promising strategy to address the tissue hyperplasia and subsequent restenosis which are major complications associated with vascular implant/interventional titanium devices. However, the uncontrollable over-proliferation of smooth muscle cells (SMCs) limits the clinical application of numerous modified strategies. Herein, a novel modified strategy involving with a two-step anodic oxidation and annealing treatment was proposed to achieve rapid re-endothelialization function regulated by regular honeycomb nanotexture and specific anatase phase on the titanium surface. Theoretical calculation revealed that the presence of nanotexture reduced the polar component of surface energy, while the generation of anatase significantly enhanced the polar component and total surface energy. Meanwhile, the modified surface with regular nanotexture and anatase phase produced positive effect on the expression of CD31, VE-Cadherin and down-regulated α-SMA proteins expression, indicating excellent capacity of pro-endothelial regeneration and inhibition of SMCs proliferation and migration. One-month in vivo implantation in rabbit carotid arteries further confirmed that modified tube implant surface effectively accelerated confluent endothelial monolayer formation and promoted native-like endothelium tissue regeneration. By contrast, original titanium tube implant induced a disorganized tissue proliferation in the lumen with a high risk of restenosis. Collectively, this study opens us an alternative route to achieve the function that selectively promotes endothelial cells (ECs) growth and suppresses SMCs on the medical titanium surface, which has a great potential in facilitating re-endothelialization on the surface of blood-contacting titanium implant.

An osteoinductive surface by adhesive bone morphogenetic protein-2 prepared using the bioorthogonal approach for tight binding of titanium with bone

Inorganic biomaterials are used in various orthopedic and dental implants. Nevertheless, they cause clinical issues such as loosening of implants and patient morbidity. Therefore, inspired by mussel adhesive proteins, we aimed to design an adhesive and dimer-forming highly active bone morphogenetic protein-2 (BMP-2) using bioorthogonal chemistry, in which recombinant DNA technology was combined with enzymatic modifications, to achieve long-term osseointegration with titanium. The prepared BMP-2 exhibited substantially higher binding activity than wild-type BMP-2, while the adhered BMP-2 was more active than soluble BMP-2. Therefore, the adhesive BMP-2 was immobilized onto titanium wires and screws and implanted into rat bones, and long-term osteogenesis was evaluated. Adhesive BMP-2 promoted the mechanical binding of titanium to bones, enabling efficient bone regeneration and effective stabilization of implants. Thus, such adhesive biosignaling proteins can be used in regenerative medicine.

Characterization and promotion of endothelialization of Bombyx mori silk fibroin functionalized with REDV peptide

In the development of small-diameter vascular grafts, it is crucial to achieve early-stage endothelialization to prevent thrombus formation and intimal hyperplasia. Silk fibroin (SF) from Bombyx mori is commonly used for such grafts. However, there is a need to expedite endothelialization post-implantation. In this study, we functionalized SF with Arg-Glu-Asp-Val (REDV) (SF + REDV) using cyanuric chloride to enhance endothelialization. The immobilization of REDV onto SF was confirmed and the amount of immobilized REDV could be calculated by 1H NMR. Furthermore, the conformational changes in Tyr, Ser, and Ala residues in [3-13C]Tyr- and [3-13C]Ser-SF due to REDV immobilization were monitored using 13C solid-state NMR. The REDV immobilized onto the SF film was found to be exposed on the film's surface, as confirmed by biotin-avidin system. Cell culture experiments, including adhesiveness, proliferation, and extensibility, were conducted using normal human umbilical vein endothelial cells (HUVEC) and normal human aortic smooth muscle cells (HAoSMC) on both SF and SF + REDV films to evaluate the impact of REDV on endothelialization. The results indicated a trend towards promoting HUVEC proliferation while inhibiting HAoSMC proliferation. Therefore, these findings suggest that SF + REDV may be more suitable than SF alone for coating small-diameter SF knitted tubes made of SF threads.

Synergistic antibacterial attributes of copper-doped polydopamine nanoparticles: an insight into photothermal enhanced antibacterial efficacy

Antibiotic-resistant bacteria and associated infectious diseases pose a grave threat to human health. The antibacterial activity of metal nanoparticles has been extensively utilized in several biomedical applications, showing that they can effectively inhibit the growth of various bacteria. In this research, copper-doped polydopamine nanoparticles (Cu@PDA NPs) were synthesized through an economical process employing deionized water and ethanol as a solvent. By harnessing the high photothermal conversion efficiency of polydopamine nanoparticles (PDA NPs) and the inherent antibacterial attributes of copper ions, we engineered nanoparticles with enhanced antibacterial characteristics. Cu@PDA NPs exhibited a rougher surface and a higher zeta potential in comparison to PDA NPs, and both demonstrated remarkable photothermal conversion efficiency. Comprehensive antibacterial evaluations substantiated the superior efficacy of Cu@PDA NPs attributable to their copper content. These readily prepared nano-antibacterial materials exhibit substantial potential in infection prevention and treatment, owing to their synergistic combination of photothermal and spectral antibacterial features.

A nitric oxide-catalytically generating carboxymethyl chitosan/sodium alginate hydrogel coating mimicking endothelium function for improving the biocompatibility

Thanks to their outstanding mechanical properties and corrosion resistance in physiological environments, titanium and its alloys are broadly explored in the field of intravascular devices. However, the biocompatibility is insufficient, causing thrombus formation and even implantation failure. In this study, inspired by the functions of endothelial glycocalyx and the NO-releasing of endothelial cells (ECs), a biomimetic coating (TNTA-Se) with three-dimensional gel-like structures and NO-catalytically generating ability was constructed on the titanium surface. To this end, the titanium alloy was firstly anodized and then annealed to form nanotube structures imitating the three-dimensional villous of glycocalyx, followed by the preparation of the Cu2+-loaded polydopamine intermediate layer for the immobilization of carboxymethyl chitosan and sodium alginate to form the hydrogel structure. Finally, an organoselenium compound (selenocystamine) as an active catalyst was covalently immobilized on the surface to develop a bioactive coating mimicking endothelial function with NO-generating activity. The surface morphologies and chemical structures of the biomimetic coating were characterized by scanning electron microscopy (SEM), energy dispersion X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), and the results indicated that the NO-catalytically generating hydrogel coating was successfully constructed. The results of water contact angle and protein adsorption suggested that the TNTA-Se coating exhibited excellent hydrophilicity, the promotion of bovine serum albumin (BSA) adsorption while the inhibition of fibrinogen (FIB) adsorption. Upon the addition of NO donor S-nitroso glutathione (GSNO) and reducing agent glutathione (GSH), the surface (TNTA-NO) displayed excellent blood compatibility and cytocompatibility to ECs. Compared with other surfaces, the TNTA-NO coating can not only further promote BSA adsorption and inhibit the adhesion and activation of platelets as well as hemolysis, but also significantly enhance ECs adhesion and proliferation and up-regulate VEGF and NO expression of ECs. The current study demonstrated that the NO-catalytically generating hydrogel coating on the titanium alloy can mimic the glycocalyx structure and endothelium function to catalyze a large number of NO donors in human blood to produce NO, and thus simultaneously enhance the surface hemocompatibility and endothelialization, representing a promising strategy for long-term cardiovascular implants of titanium-based devices.

Gas station in blood vessels: An endothelium mimicking, self-sustainable nitric oxide fueling stent coating for prevention of thrombosis and restenosis

Stenting is the primary treatment for vascular obstruction-related cardiovascular diseases, but it inevitably causes endothelial injury which may lead to severe thrombosis and restenosis. Maintaining nitric oxide (NO, a vasoactive mediator) production and grafting endothelial glycocalyx such as heparin (Hep) onto the surface of cardiovascular stents could effectively reconstruct the damaged endothelium. However, insufficient endogenous NO donors may impede NO catalytic generation and fail to sustain cardiovascular homeostasis. Here, a dopamine-copper (DA-Cu) network-based coating armed with NO precursor L-arginine (Arg) and Hep (DA-Cu-Arg-Hep) is prepared using an organic solvent-free dipping technique to form a nanometer-thin coating onto the cardiovascular stents. The DA-Cu network adheres tightly to the surface of stents and confers excellent NO catalytic activity in the presence of endogenous NO donors. The immobilized Arg functions as a NO fuel to generate NO via endothelial nitric oxide synthase (eNOS), while Hep works as eNOS booster to increase the level of eNOS to decompose Arg into NO, ensuring a sufficient supply of NO even when endogenous donors are insufficient. The synergistic interaction between Cu and Arg is analogous to a gas station to fuel NO production to compensate for the insufficient endogenous NO donor in vivo. Consequently, it promotes the reconstruction of natural endothelium, inhibits smooth muscle cell (SMC) migration, and suppresses cascading platelet adhesion, preventing stent thrombosis and restenosis. We anticipate that our DA-Cu-Arg-Hep coating will improve the quality of life of cardiovascular patients through improved surgical follow-up, increased safety, and decreased medication, as well as revitalize the stenting industry through durable designs.

Vascular cells responses to controlled surface structure and properties of bacterial nanocellulose artificial blood vessel after mercerization

Therapeutic benefits of small caliber artificial blood vessels to cure cardio and cerebrovascular diseases are mainly limited by their low patency during long-term transplantation. Bacterial nanocellulose (BNC), as a natural polysaccharide mainly synthesized by a bacterium Komagataeibatacter xylinus, has shown great potential in small-caliber vascular graft applications due to its shape controllability, and furthermore its physical surface structure can be adjusted with different treatments. However, influences of physical surface structure and properties of BNC conduits on behaviors of vascular cells have not been investigated. In this work, mercerized BNC conduits (MBNC) with different surface roughness and stiffness were constructed by controlled alkali (NaOH) treatment. The changes of surface structures and properties significantly affected the behaviors of vascular cells and gene expression; meanwhile, the cell seeding density also affected the cell responses. After mercerization with NaOH concentration > 10 %, it was observed that the increased stiffness of MBNC decreased several functional gene expressions of human vascular endothelial cells, and the pathological transformation of smooth muscle cells was inhibited. This study demonstrates physical surface structure of MBNC conduits will critically regulate functions and behaviors of vascular cells and it also provides important designing parameters to improve the long-term patency of BNC-based conduits.

Silk fibroin/chitosan coating with tunable catalytic nitric oxide generation for surface functionalization of cardiovascular stents

Developing a functional coating for vascular stents with sustainable and tunable NO release remains challenging. In this work, we report a silk fibroin/chitosan-based biopolymer coating incorporating copper ions as a catalyst for NO generation and demonstrate its potential for the surface functionalization of cardiovascular stents. Based on the differences in silk fibroin and chitosan coordinating with copper ions, the loading, bonding, and release of copper ions could be precisely regulated over a wide range by controlling the ratio of silk fibroin and chitosan. This system shows good cytocompatibility for endothelial cells and tunable catalytic activity to decompose S-nitroso-N-acetyl-D-penicillamine (SNAP) for NO generation. Consequently, a functionalized coating with sustainable and tunable NO catalysis generation was developed on the metallic stent. Based on good biocompatibility, tunable NO release, and simple processing, the coating is expected to have great promise in the field of intervention therapy of cardiovascular disease.

A Polymeric Strategy Empowering Vascular Cell Selectivity and Potential Application Superior to Extracellular Matrix Peptides

Endothelialization of vascular implants plays a vital role in maintaining the long-term vascular patency. In situ endothelialization and re-endothelialization is generally achieved by selectively promoting endothelial cell (EC) adhesion and, meanwhile, suppressing smooth muscle cell (SMC) adhesion. Currently, such EC versus SMC selectivity is achieved and extensively used in vascular-related biomaterials utilizing extracellular-matrix-derived EC-selective peptides, dominantly REDV and YIGSR. Nevertheless, the application of EC-selective peptides is limited due to their easy proteolysis, time-consuming synthesis, and expensiveness. To address these limitations, a polymeric strategy in designing and finding EC-selective biomaterials using amphiphilic β-peptide polymers by tuning serum protein adsorption is reported. The optimal β-peptide polymer displays EC versus SMC selectivity even superior to EC-selective REDV peptide regarding cell adhesion, proliferation, and migration of ECs versus SMCs. Study of the mechanism indicates that surface adsorption of bovine serum albumin, an abundant and anti-adhesive serum protein, plays a critical role in the ECs versus SMCs selectivity of β-peptide polymer. In addition, surface modification of the optimal β-peptide polymer effectively promotes the endothelialization of vascular implants and inhibits intimal hyperplasia. This study provides an alternative strategy in designing and finding EC-selective biomaterials, implying great potential in the vascular-related biomaterial study and application.

Anticancer and Anti-Inflammatory Mechanisms of NOSH-Aspirin and Its Biological Effects

NOSH-Aspirin, which is generated from NO, H2S, and aspirin, affects a variety of essential pathophysiological processes, including anti-inflammatory, analgesic, antipyretic, antiplatelet, and anticancer properties. Although many people acknowledge the biological significance of NOSH-Aspirin and its therapeutic effects, the mechanism of action of NOSH-Aspirin and its regulation of tissue levels remains obscure. This is in part due to its chemical and physical features, which make processing and analysis difficult. This review focuses on the biological effects of NOSH-Aspirin and provides a comprehensive analysis to elucidate the mechanism underlying its disease-protective benefits.

Facile fabrication of copper-incorporating poly(ε-caprolactone)/keratin mats for tissue-engineered vascular grafts with the potential of catalytic nitric oxide generation

Tissue-engineered vascular grafts (TEVGs) provide a new alternative for vascular construction. Nitric oxide (NO) is capable of promoting vascular tissue regeneration and reducing restenosis caused by vascular implantation. Therefore, in situ production of NO by catalytic decomposition of the endogenous donor is a promising strategy to fabricate a TEVG. In this study, poly(ε-caprolactone) (PCL) was first electrospun with keratin (Ker) to afford PCL/Ker mats and then incorporated with Cu(II) ions through multiple interactions. This strategy is very simple, green, and facile. Particularly, the incorporated Cu(II) ions were partially reduced to Cu(I) ions due to the reducibility of keratin. The chelated copper ions were expected to catalyze the generation of NO from endogenous S-nitrosothiol (RSNO). As a result, PCL/Ker-Cu mats selectively accelerated the adhesion, migration, and growth of human umbilical vein endothelial cells (HUVECs), while inhibiting the proliferation of human umbilical artery smooth muscle cells (HUASMCs). Furthermore, these mats exhibited excellent blood compatibility and significant antibacterial activity. Vascular implantation in vivo indicated that the tubular mats could inhibit thrombus formation and retain patency for 3 months after implantation in the rabbit carotid artery. More importantly, vascular remodeling was observed during follow-up, including a complete endothelium and smooth muscle layer. Taken together, the PCL/Ker-Cu mats have great potential application in vascular tissue regeneration.

Recent Development of Polydopamine Anti-Bacterial Nanomaterials

Polydopamine (PDA), as a mussel-inspired material, exhibits numerous favorable performance characteristics, such as a simple preparation process, prominent photothermal transfer efficiency, excellent biocompatibility, outstanding drug binding ability, and strong adhesive properties, showing great potential in the biomedical field. The rapid development of this field in the past few years has engendered substantial progress in PDA antibacterial materials. This review presents recent advances in PDA-based antimicrobial materials, including the preparation methods and antibacterial mechanisms of free-standing PDA materials and PDA-based composite materials. Furthermore, the urgent challenges and future research opportunities for PDA antibacterial materials are discussed.

Cu(II)-functionalized silk fibroin films for the catalytic generation of nitric oxide

In situ release of nitric oxide (NO) has been suggested to be a potential functionalization strategy for blood-contacting implants. In this study, the NO generation capability catalyzed by the copper ion-incorporated silk fibroin (SF) films in the presence of S-nitroso-N-acetyl-dl-penicillamine (SNAP) is demonstrated. Cu(II) is effectively bound to the surface of the SF film based on metal-protein coordination. The x-ray photoelectron spectroscopy results indicate that copper ions may exist on the surface of the SF film in the form of Cu(II)/Cu(I) coexistence. The degradation behavior showed that the bound copper ions on the surface of the SF films can maintain a slow release in phosphate-buffered saline (PBS) or collagenase IA solution for 7 days. There was no significant difference in the release of copper ions between PBS degradation and enzyme degradation. The loading of copper ions significantly improved the release of NO from SNAP through catalysis. Based on the biological effects of copper ions and the ability to catalyze the release of NO from S-nitrosothiols, copper ion loading provides an option for the construction of bioactive SF biomaterials.

Preparation of 4D printed peripheral vascular stent and its degradation behavior under fluid shear stress after deployment

Shape memory stents are mild intervention devices for vascular diseases as compared to balloon-dilated ones; however, their degradation behavior under blood shear stress after deployment also deserves further attention. To understand the degradation behavior, we first prepared 4D printed poly(lactic acid) (PLA) stents via 3D printing technology and studied their failure behavior in a dynamic condition after self-expandable deployment. Mechanical property tests showed that the 4D printed stents had a compression force of 0.06-0.39 N mm^-1 and a recovery ratio of 85.3-93.4%, respectively, which was verified to be wall thickness dependent. The stents were then implanted in simulated blood vessels with minimal microstructural damage at 60 °C followed by 8-week degradation tests. The results showed the microstructure damage caused by deployment could accelerate the degradation of stents faster than fluid shear stress. Furthermore, we conducted microstructural analysis and numerical simulation on the stent by finite element analysis (FEA) to explain the relationship between stent injury, vascular injury, and stent deployment temperature. A physical model derived from micro-morphologies on the degradation mechanism of PLA was also proposed. These results may provide new insights for the examination of the degradation behavior of 4D printed stents and minimize medical risk.

A nitric oxide-eluting and REDV peptide-conjugated coating promotes vascular healing

Drug-eluting stents (DESs) placement remarkably reduces the over-proliferation of smooth muscle cells (SMCs) and thus neointimal hyperplasia. However, the pharmacological agent also slows down the re-endothelization, delays injury vascular healing and increases the risk of in-stent restenosis (ISR). Here, inspired by mussel foot proteins (Mfps), a mimicking endothelium functional stent coating was efficiently fabricated by thiol-ene "click" reaction, consisting of catechol grafted chitosan (CS-C), zinc sulfate, and Arg-Glu-Asp-Val (REDV) peptide. The mimicking endothelium coating could continuously catalyze endogenous nitric oxide (NO) gas and maintain the bioactivity of REDV peptide. Compared with bare stents, the mimicking coatings significantly inhibited the acute thrombosis for the first 1-week, accelerated re-endothelization and decreased in-stent restenosis for 1- and 3-month after implantation. In addition, the synergistic effect of NO and REDV peptide also regulated inflammation response and promoted the expression of muscle fiber.

Tailoring ZE21B Alloy with Nature-Inspired Extracellular Matrix Secreted by Micro-Patterned Smooth Muscle Cells and Endothelial Cells to Promote Surface Biocompatibility

Delayed surface endothelialization is a bottleneck that restricts the further application of cardiovascular stents. It has been reported that the nature-inspired extracellular matrix (ECM) secreted by the hyaluronic acid (HA) micro-patterned smooth muscle cells (SMC) and endothelial cells (EC) can significantly promote surface endothelialization. However, this ECM coating obtained by decellularized method (dECM) is difficult to obtain directly on the surface of degradable magnesium (Mg) alloy. In this study, the method of obtaining bionic dECM by micro-patterning SMC/EC was further improved, and the nature-inspired ECM was prepared onto the Mg-Zn-Y-Nd (ZE21B) alloy surface by self-assembly. The results showed that the ECM coating not only improved surface endothelialization of ZE21B alloy, but also presented better blood compatibility, anti-hyperplasia, and anti-inflammation functions. The innovation and significance of the study is to overcome the disadvantage of traditional dECM coating and further expand the application of dECM coating to the surface of degradable materials and materials with different shapes.

Tapping basement membrane motifs: Oral junctional epithelium for surface-mediated soft tissue attachment to prevent failure of percutaneous devices

Teeth, long-lasting percutaneous organs, feature soft tissue attachment through adhesive structures, hemidesmosomes, in the junctional epithelium basement membrane adjacent to teeth. This soft tissue attachment prevents bacterial infection of the tooth despite the rich - and harsh - microbial composition of the oral cavity. Conversely, millions of percutaneous devices (catheters, dental, and orthopedic implants) fail from infection yearly. Standard of care antibiotic usage fuels antimicrobial resistance and is frequently ineffective. Infection prevention strategies, like for dental implants, have failed in generating durable soft tissue adhesion - like that seen with the tooth - to prevent bacterial colonization at the tissue-device interface. Here, inspired by the impervious natural attachment of the junctional epithelium to teeth, we synthesized four cell adhesion peptide (CAPs) nanocoatings, derived from basement membranes, to promote percutaneous device soft tissue attachment. The two leading nanocoatings upregulated integrin-mediated hemidesmosomes, selectively increased keratinocyte proliferation compared to fibroblasts, which cannot form hemidesmosomes, and expression of junctional epithelium adhesive markers. CAP nanocoatings displayed marked durability under simulated clinical conditions and the top performer CAP nanocoating was validated in a percutaneous implant murine model. Basement membrane CAP nanocoatings, inspired by the tooth and junctional epithelium, may provide an alternative anti-infective strategy for percutaneous devices to mitigate the worldwide threat of antimicrobial resistance. STATEMENT OF SIGNIFICANCE: Prevention and management of medical device infection is a significant healthcare challenge. Overzealous antibiotic use has motivated alternative material innovations to prevent infection. Here, we report implant cell adhesion peptide nanocoatings that mimic a long-lasting, natural "medical device," the tooth, through formation of cell adhesive structures called hemidesmosomes. Such nanocoatings sidestep the use of antimicrobial or antibiotic elements to form a soft-tissue seal around implants. The top performing nanocoatings prompted expression of hemidesmosomes and defensive factors to mimic the tooth and was validated in an animal model. Application of cell adhesion peptide nanocoatings may provide an alternative to preventing, rather that necessarily treating, medical device infection across a range of device indications, like dental implants.

Advances in hydrogel-based vascularized tissues for tissue repair and drug screening

The construction of biomimetic vasculatures within the artificial tissue models or organs is highly required for conveying nutrients, oxygen, and waste products, for improving the survival of engineered tissues in vitro. In recent times, the remarkable progress in utilizing hydrogels and understanding vascular biology have enabled the creation of three-dimensional (3D) tissues and organs composed of highly complex vascular systems. In this review, we give an emphasis on the utilization of hydrogels and their advantages in the vascularization of tissues. Initially, the significance of vascular elements and the regeneration mechanisms of vascularization, including angiogenesis and vasculogenesis, are briefly introduced. Further, we highlight the importance and advantages of hydrogels as artificial microenvironments in fabricating vascularized tissues or organs, in terms of tunable physical properties, high similarity in physiological environments, and alternative shaping mechanisms, among others. Furthermore, we discuss the utilization of such hydrogels-based vascularized tissues in various applications, including tissue regeneration, drug screening, and organ-on-chips. Finally, we put forward the key challenges, including multifunctionalities of hydrogels, selection of suitable cell phenotype, sophisticated engineering techniques, and clinical translation behind the development of the tissues with complex vasculatures towards their future development.

A Nanocoating Co-Localizing Nitric Oxide and Growth Factor onto Individual Endothelial Cells Reveals Synergistic Effects on Angiogenesis

The delivery of nitric oxide (NO)-an intrinsic cellular signaling molecule-is promising for disease treatment, in particular to vascular diseases, due to its endothelial-derived inherent nature. The limited diffusion distance of labile NO prompts researchers to develop various carriers and targeting methods for specific sites. In contrast to the apoptotic effect of NO, such as anticancer, delivering low NO concentration at the desired targeting area is still intricate in a physiological environment. In this study, the layer-by-layer assembled nanocoating is leveraged to develop a direct NO delivery platform to individual endothelial cells (ECs). NO can be localized to individual ECs via S-nitrosothiol-bound polyacrylic acid which is a polymer directly providing an endothelial-like constant level of NO. To increase angiogenic activation along with NO, VEGF is additionally applied to specific receptors on the cell surface. Notably, the survival and proliferation of ECs are significantly increased by a synergistic effect of NO and VEGF co-localized via nanocoating. Furthermore, the nanocoating remarkably promoted cell migration and tubule formation-prerequisites of angiogenesis. The proposed unique technology based on nanocoating demonstrates great potential for conferring desired angiogenic functions to individual ECs through efficient NO delivery.

Endothelialization strategy of implant materials surface: The newest research in recent 5 years

In recent years, more and more metal or non-metal materials have been used in the treatment of cardiovascular diseases, but the vascular complications after transplantation are still the main factors restricting the clinical application of most grafts, such as acute thrombosis and graft restenosis. Implant materials have been extensively designed and surface optimized by researchers, but it is still too difficult to avoid complications. Natural vascular endodermis has excellent function, anti-coagulant and anti-intimal hyperplasia, and it is also the key to maintaining the homeostasis of normal vascular microenvironment. Therefore, how to promote the adhesion of endothelial cells (ECs) on the surface of cardiovascular materials to achieve endothelialization of the surface is the key to overcoming the complications after implant materialization. At present, the surface endothelialization design of materials based on materials surface science, bioactive molecules, and biological function intervention and feedback has attracted much attention. In this review, we summarize the related research on the surface modification of materials by endothelialization in recent years, and analyze the advantages and challenges of current endothelialization design ideas, explain the relationship between materials, cells, and vascular remodeling in order to find a more ideal endothelialization surface modification strategy for future researchers to meet the requirements of clinical biocompatibility of cardiovascular materials.

Endogenous nitric oxide-generating surfaces via polydopamine-copper coatings for preventing biofilm dispersal and promoting microbial killing

INTRODUCTION

Peri-implantitis is a bacterially induced inflammatory disease which affects the hard and soft tissues around a dental implant. Microbial biofilm formation is an important causative factor in peri-implantitis. The aim of this study is to develop an effective multifunctional surface coating for antimicrobial property and to counteract oral biofilm-associated infections via a single polydopamine copper coating (PDAM@Cu) on titanium implant surface to regulate endogenous nitric oxide (NO) generation.

METHODS

PDAM@Cu coatings were made with different concentrations of CuCl₂ on titanium surfaces with a simple dip coating technique. Coatings were characterised to evaluate Cu concentrations as well as NO release rates from the coatings. Further, salivary biofilms were made on the coatings using Brain Heart Infusion (BHI) media in an anaerobic chamber. Biofilms were prepared with three different mixtures, one of which was saliva only, the second had an addition of sheep's blood, and the third was prepared with NO donors S-nitrosoglutathione (GSNO) and L-glutathione (GSH) in the mixture of saliva and blood to evaluate the effects of endogenously produced NO on biofilms. The effectiveness of coated surfaces on biofilms were assessed using four different methods, namely, crystal violet assay, scanning electron microscopy imaging, 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino) carbonyl]-2H-tetrazolium hydroxide (XTT) metabolic assay, and live/dead staining.

RESULTS

NO release rates could be controlled with different Cu concentration in PDAM@Cu coatings. NO generated from the PDAM@Cu coatings effectively induced dispersal of biofilms shown by the reduction in biofilm biomass as well as reduced biofilm attachment in samples prepared with blood and NO donors. Cu ions released from the PDAM@Cu coatings resulted in killing of the dispersed bacteria, which was evidenced by the live/dead cell staining and reduced metabolic activity noted from the XTT assay. In contrast, samples prepared with saliva showed no significant reduction in biofilms, indicating the important effect of endogenously generated NO on biofilm dispersal.

CONCLUSION

In conclusion, PDAM@Cu coatings with NO generating surfaces have a dual anti-biofilm function, with a synergistic effect on biofilm dispersal from regulated NO generation and bactericidal effects from Cu ions from the coatings.

Surface modification of polytetrafluoroethylene (PTFE) with a heparin-immobilized extracellular matrix (ECM) coating for small-diameter vascular grafts applications

Intimal hyperplasia, thrombosis formation, and delayed endothelium regeneration are the main causes that restrict the clinical applications of PTFE small-diameter vascular grafts (inner diameter < 6 mm). An ideal strategy to solve such problems is to facilitate in situ endothelialization. Since the natural vascular endothelium adheres onto the basement membrane, which is a specialized form of extracellular matrix (ECM) secreted by endothelial cells (ECs) and smooth muscle cells (SMCs), functionalizing PTFE with an ECM coating was proposed. However, besides ECs, the ECM-modified PTFE improved SMC growth as well, thereby increasing the risk of intimal hyperplasia. In the present study, heparin was immobilized on the ECM coating at different densities (4.89 ± 1.02 μg/cm2, 7.24 ± 1.56 μg/cm2, 15.63 ± 2.45 μg/cm2, and 26.59 ± 3.48 μg/cm2), aiming to develop a bio-favorable environment that possessed excellent hemocompatibility and selectively inhibited SMC growth while promoting endothelialization. The results indicated that a low heparin density (4.89 ± 1.02 μg/cm2) was not enough to restrict platelet adhesion, whereas a high heparin density (26.59 ± 3.48 μg/cm2) resulted in decreased EC growth and enhanced SMC proliferation. Therefore, a heparin density at 7.24 ± 1.56 μg/cm2 was the optimal level in terms of antithrombogenicity, endothelialization, and SMC inhibition. Collectively, this study proposed a heparin-immobilized ECM coating to modify PTFE, offering a promising means to functionalize biomaterials for developing small-diameter vascular grafts.

Polyphenol-Containing Nanoparticles: Synthesis, Properties, and Therapeutic Delivery

Polyphenols, the phenolic hydroxyl group-containing organic molecules, are widely found in natural plants and have shown beneficial effects on human health. Recently, polyphenol-containing nanoparticles have attracted extensive research attention due to their antioxidation property, anticancer activity, and universal adherent affinity, and thus have shown great promise in the preparation, stabilization, and modification of multifunctional nanoassemblies for bioimaging, therapeutic delivery, and other biomedical applications. Additionally, the metal-polyphenol networks, formed by the coordination interactions between polyphenols and metal ions, have been used to prepare an important class of polyphenol-containing nanoparticles for surface modification, bioimaging, drug delivery, and disease treatments. By focusing on the interactions between polyphenols and different materials (e.g., metal ions, inorganic materials, polymers, proteins, and nucleic acids), a comprehensive review on the synthesis and properties of the polyphenol-containing nanoparticles is provided. Moreover, the remarkable versatility of polyphenol-containing nanoparticles in different biomedical applications, including biodetection, multimodal bioimaging, protein and gene delivery, bone repair, antibiosis, and cancer theranostics is also demonstrated. Finally, the challenges faced by future research regarding the polyphenol-containing nanoparticles are discussed.

Coaxial-printed small-diameter polyelectrolyte-based tubes with an electrostatic self-assembly of heparin and YIGSR peptide for antithrombogenicity and endothelialization

Low patency ratio of small-diameter vascular grafts remains a major challenge due to the occurrence of thrombosis formation and intimal hyperplasia after transplantation. Although developing the functional coating with release of bioactive molecules on the surface of small-diameter vascular grafts are reported as an effective strategy to improve their patency ratios, it is still difficult for current functional coatings cooperating with spatiotemporal control of bioactive molecules release to mimic the sequential requirements for antithrombogenicity and endothelialization. Herein, on basis of 3D-printed polyelectrolyte-based vascular grafts, a biologically inspired release system with sequential release in spatiotemporal coordination of dual molecules through an electrostatic self-assembly was first described. A series of tubes with tunable diameters were initially fabricated by a coaxial extrusion printing method with customized nozzles, in which a polyelectrolyte ink containing of ε-polylysine and sodium alginate was used. Further, dual bioactive molecules, heparin with negative charges and Tyr-Ile-Gly-Ser-Arg (YIGSR) peptide with positive charges were layer-by-layer assembled onto the surface of these 3D-printed tubes. Due to the electrostatic interaction, the sequential release of heparin and YIGSR was demonstrated and could construct a dynamic microenvironment that was thus conducive to the antithrombogenicity and endothelialization. This study opens a new avenue to fabricate a small-diameter vascular graft with a biologically inspired release system based on electrostatic interaction, revealing a huge potential for development of small-diameter artificial vascular grafts with good patency.

Polydopamine antibacterial materials

Recently, the development of polydopamine (PDA) has demonstrated numerous excellent performances in free radical scavenging, UV shielding, photothermal conversion, and biocompatibility. These unique properties enable PDA to be widely used as efficient antibacterial materials for various applications. Accordingly, PDA antibacterial materials mainly include free-standing PDA materials and PDA-based composite materials. In this review, an overview of PDA antibacterial materials is provided to summarize these two types of antibacterial materials in detail, including the fabrication strategies and antibacterial mechanisms. The future development and challenges of PDA in this field are also presented. It is hoped that this review will provide an insight into the future development of antibacterial functional materials based on PDA.

Silanization of a Metal-Polyphenol Coating onto Diverse Substrates as a Strategy for Controllable Wettability with Enhanced Performance to Resist Acid Corrosion

Wettability is a crucial characteristic of materials that plays a vital role in surface engineering. Surface modification is the key to changing the wettability of materials, and a simple and universal modification approach is being extensively pursued by researchers. Recently, metal-phenolic networks (MPNs) have been widely studied because they impart versatility and functionality in surface modification. However, an MPN is not stable for long periods, especially under acidic conditions, and is susceptible to pollution by invasive species. Spurred by the versatility of MPNs and various functionalities achieved by silanization, we introduce a general strategy to fabricate functionally stable coatings with controllable surface wettability by combining the two methods. The formation process of MPN and silane-MPN coatings was characterized by spectroscopic ellipsometry (SE), UV-visible-near-infrared (UV-vis-NIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), atomic force microscopy (AFM), water contact angle (WCA), etc. We found that the stability of the MPN was greatly enhanced after silanization, which is attributed to the cross-linking effect that occurs between silane and the MPN, namely, the cross-linking protection produced in this case. Additionally, the wettability of an MPN can be easily changed through our strategy. We trust that our strategy can further extend the applications of MPNs and points toward potential prospects in surface modification.

Surface bioengineering of diverse orthopaedic implants with optional functions via bioinspired molecular adhesion and bioorthogonal conjugations

In this work, we reported an upgraded mussel-inspired strategy for surface bioengineering of osteoimplants by combination of mussel adhesion and bioorthogonal click chemistry. The main idea of this strategy is a mussel-inspired synthetic peptide containing multiple 3,4-dihydroxy-L-phenylalanine (DOPA) units and a dibenzocyclooctyne (DBCO) terminal (DOPA-DBCO). According to the mussel adhesion mechanism, the DOPA-DBCO peptide could stably adhere onto a variety of material surface, leaving the residual DBCO groups on the surface. Then, the DBCO residues could be employed for a second-step bioorthogonal conjugation with azide-capping biomolecules through bioorthogonal click chemistry, finally leading to the biomodified surfaces. To demonstrate the generality of our strategy for surface biomodification of diversified orthopaedic materials including metallic and polymeric substrates, we here conceptually conjugated some typical azide-capping biomolecules on both metal and polymeric surfaces. The results definitely verified the feasibility for engineering of functional surfaces with some essential requirements of osteoimplants, for example, the ability to facilitate cell adhesion, suppress bacterial infection, and promote osteogenesis. In a word, this study indicated that our novel surface strategy would show broad applicability for diverse osteoimplants and in different biological scenarios. We can also image that the molecular specificity of bioorthogonal conjugation and the universality of mussel adhesion mechanism may jointly provide a versatile surface bioengineering method for a wider range of biomedical implants.

In-situ biotransformation of nitric oxide by functionalized surfaces of cardiovascular stents

Cardiovascular diseases (CVDs) are among the leading causes of mortality and morbidity worldwide. Nitric oxide (NO) is a signalling molecule that plays a vital role in protecting and regulating cardiovascular function and homeostasis. Despite several successful outcomes of exogenous supplementation of NO for cardiovascular disease therapy, a great challenge lies in controlled and long-term delivery due to the short half-life and instability of NO. Recently, increasing attention has been paid to the in situ conversion of endogenous NO donors catalysed by functional surfaces. Based on bioinspired and biomimicking strategies, a series of surface functionalization methods for cardiovascular stents has been successfully developed. By further combining NO catalysis with other biofunctionalities, improved endothelium healing and long-term patency can be anticipated.

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Nitric oxide (NO) is a signalling molecule that plays a vital role in cardiovascular system.

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Surface functionalization provides a promising strategy for the in situ generation of NO from endogenous donors.

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Combining NO catalysis with other surface biofunctionalities could enhance long-term patency of the cardiovascular stents.

Mimicking the Nitric Oxide-Releasing and Glycocalyx Functions of Endothelium on Vascular Stent Surfaces

Endothelium can secrete vasoactive mediators and produce specific extracellular matrix, which contribute jointly to the thromboresistance and regulation of vascular cell behaviors. From a bionic point of view, introducing endothelium-like functions onto cardiovascular stents represents the most effective means to improve hemocompatibility and reduce late stent restenosis. However, current surface strategies for vascular stents still have limitations, like the lack of multifunctionality, especially the monotony in endothelial-mimic functions. Herein, a layer-by-layer grafting strategy to create endothelium-like dual-functional surface on cardiovascular scaffolds is reported. Typically, a nitric oxide (NO, vasoactive mediator)-generating compound and an endothelial polysaccharide matrix molecule hyaluronan (HA) are sequentially immobilized on allylamine-plasma-deposited stents through aqueous amidation. In this case, the stents could be well-engineered with dual endothelial functions capable of remote and close-range regulation of the vascular microenvironment. The synergy of NO and endothelial glycocalyx molecules leads to efficient antithrombosis, smooth muscle cell (SMC) inhibition, and perfect endothelial cell (EC)-compatibility of the stents in vitro. Moreover, the dual-functional stents show efficient antithrombogenesis ex vivo, rapid endothelialization, and long-term prevention of restenosis in vivo. Therefore, this study will provide new solutions for not only multicomponent surface functionalization but also the bioengineering of endothelium-mimic vascular scaffolds with improved clinical outcomes.

Surface Engineering of Cardiovascular Devices for Improved Hemocompatibility and Rapid Endothelialization

Cardiovascular devices have been widely applied in the clinical treatment of cardiovascular diseases. However, poor hemocompatibility and slow endothelialization on their surface still exist. Numerous surface engineering strategies have mainly sought to modify the device surface through physical, chemical, and biological approaches to improve surface hemocompatibility and endothelialization. The alteration of physical characteristics and pattern topographies brings some hopeful outcomes and plays a notable role in this respect. The chemical and biological approaches can provide potential signs of success in the endothelialization of vascular device surfaces. They usually involve therapeutic drugs, specific peptides, adhesive proteins, antibodies, growth factors and nitric oxide (NO) donors. The gene engineering can enhance the proliferation, growth, and migration of vascular cells, thus boosting the endothelialization. In this review, the surface engineering strategies are highlighted and summarized to improve hemocompatibility and rapid endothelialization on the cardiovascular devices. The potential outlook is also briefly discussed to help guide endothelialization strategies and inspire further innovations. It is hoped that this review can assist with the surface engineering of cardiovascular devices and promote future advancements in this emerging research field.

Bioclickable and mussel adhesive peptide mimics for engineering vascular stent surfaces

Thrombogenic reaction, aggressive smooth muscle cell (SMC) proliferation, and sluggish endothelial cell (EC) migration onto bioinert metal vascular stents make poststenting reendothelialization a dilemma. Here, we report an easy to perform, biomimetic surface engineering strategy for multiple functionalization of metal vascular stents. We first design and graft a clickable mussel-inspired peptide onto the stent surface via mussel-inspired adhesion. Then, two vasoactive moieties [i.e., the nitric-oxide (NO)-generating organoselenium (SeCA) and the endothelial progenitor cell (EPC)-targeting peptide (TPS)] are clicked onto the grafted surfaces via bioorthogonal conjugation. We optimize the blood and vascular cell compatibilities of the grafted surfaces through changing the SeCA/TPS feeding ratios. At the optimal ratio of 2:2, the surface-engineered stents demonstrate superior inhibition of thrombosis and SMC migration and proliferation, promotion of EPC recruitment, adhesion, and proliferation, as well as prevention of in-stent restenosis (ISR). Overall, our biomimetic surface engineering strategy represents a promising solution to address clinical complications of cardiovascular stents and other blood-contacting metal materials.

Poly-l-lysine/Sodium Alginate Coating Loading Nanosilver for Improving the Antibacterial Effect and Inducing Mineralization of Dental Implants

In recent years, antibacterial surface modification of titanium (Ti) implants has been widely studied in preventing implant-associated infection for dental and orthopedic applications. The purpose of this study was to prepare a composite coating on a porous titanium surface for infection prevention and inducing mineralization, which was initialized by deposition of a poly-l-lysine (PLL)/sodium alginate(SA)/PLL self-assembled coating, followed by dopamine deposition, and finally in situ reduction of silver nanoparticles (AgNPs) by dopamine. The surface zeta potential, SEM, XPS, UV-vis, and water contact angle analyses demonstrate that each coating was successfully prepared after the respective steps and that the average sizes of AgNPs were 20-30 nm. The composite coating maintained Ag⁺ release for more than 27 days in PBS and induced mineralization when incubated in SBF. The antibacterial results showed that the composite coating inhibited/killed bacteria on the material surface and killed bacteria around them. In addition, although this coating inhibited the initial adhesion of osteoblasts, the mineralized surface greatly enhanced the cytocompatibility. Thus, we concluded that the composite coating could prevent bacterial infections and facilitate mineralization in vivo in the early postoperative period, and then, the mineralized surface could enhance the cytocompatibility.

A Versatile Surface Bioengineering Strategy Based on Mussel-Inspired and Bioclickable Peptide Mimic

In this work, we present a versatile surface engineering strategy by the combination of mussel adhesive peptide mimicking and bioorthogonal click chemistry. The main idea reflected in this work derived from a novel mussel-inspired peptide mimic with a bioclickable azide group (i.e., DOPA₄-azide). Similar to the adhesion mechanism of the mussel foot protein (i.e., covalent/noncovalent comediated surface adhesion), the bioinspired and bioclickable peptide mimic DOPA₄-azide enables stable binding on a broad range of materials, such as metallic, inorganic, and organic polymer substrates. In addition to the material universality, the azide residues of DOPA₄-azide are also capable of a specific conjugation of dibenzylcyclooctyne- (DBCO-) modified bioactive ligands through bioorthogonal click reaction in a second step. To demonstrate the applicability of this strategy for diversified biofunctionalization, we bioorthogonally conjugated several typical bioactive molecules with DBCO functionalization on different substrates to fabricate functional surfaces which fulfil essential requirements of biomedically used implants. For instance, antibiofouling, antibacterial, and antithrombogenic properties could be easily applied to the relevant biomaterial surfaces, by grafting antifouling polymer, antibacterial peptide, and NO-generating catalyst, respectively. Overall, the novel surface bioengineering strategy has shown broad applicability for both the types of substrate materials and the expected biofunctionalities. Conceivably, the "clean" molecular modification of bioorthogonal chemistry and the universality of mussel-inspired surface adhesion may synergically provide a versatile surface bioengineering strategy for a wide range of biomedical materials.