The future of Tissue Adhesives & Biocompatible Coatings 2026

03 Mar, 2026 | Guides & Resources, Material Science - Guide

When designing materials intended to interface with living tissue—such as dental and orthopaedic prostheses, adhesives for stabilising bone fractures and closing surgical wounds, or drug-eluting surfaces for controlled therapeutic delivery—two persistent challenges dominate: achieving strong, reliable adhesion in complex biological environments, and minimising material-associated complications such as inflammation, infection, or poor integration [1].

This article explores the materials science behind modern tissue adhesives and biocompatible coatings, with a particular focus on the advanced characterisation methodologies that support their optimisation, performance validation, and successful translation from laboratory research to clinical practice.

The Evolution of Medical Adhesives and Coatings

Replacing sutures, early tissue adhesives were largely inspired by simple cyanoacrylate chemistries, valued for their fast-setting times but limited by brittleness, toxicity concerns, and poor long-term biocompatibility. Similarly, first-generation coatings for medical devices focused primarily on creating barriers, with minimal consideration of biological interaction.

Modern tissue adhesives are increasingly based on natural polymers, synthetic hydrogels, and bioinspired systems that mimic mechanisms found in nature, like mussel-inspired catechol chemistries [2]. These advances have enabled improved elasticity, controlled degradation, and stronger adhesion in wet and dynamic biological environments. Biocompatible coatings have evolved from passive surface treatments to active, functional layers. Today’s coatings are designed not only to protect devices, but also to promote cell attachment and tissue regeneration, reduce inflammation, prevent biofouling and even to deliver therapeutic agents in a controlled manner [3].

This evolution has been supported by advances in material characterisation technologies. High-resolution particle and surface interaction analysis allow researchers to optimise their formulations with high precision. By combining complementary analytical techniques, researchers gain the insights needed to design safer, more effective materials that perform as intended in complex biological environments.

Tissue Adhesives: Materials and Mechanisms

Adhesion to living tissue is more challenging than to dry surfaces. Interfacial water, tissue motion, and chemical heterogeneity reduce adhesive strength, requiring materials to effectively displace water and maintain stable bonds under dynamic physiological conditions [4].

Synthetic Adhesives: Cyanoacrylates

Cyanoacrylates (also known as “super glues’’) polymerise rapidly upon contact with moisture, forming strong, rigid chains that bond tissue surfaces. Fast setting, strong initial adhesion, and ease of application make them ideal for closing small wounds and minor surgical incisions. Traditional cyanoacrylates can be brittle, cytotoxic in high concentrations, and generate heat during polymerisation, limiting use on sensitive tissues. New modified cyanoacrylates include longer-chain variants and blends with additives to improve flexibility, reduce toxicity, and allow controlled degradation, expanding use to internal and delicate tissues [5].

Biologically-Derived Adhesives

Biologically derived tissue adhesives like fibrin, chitosan or mussel adhesive proteins, usually bond tissues via enzymatic crosslinking, offering high biocompatibility and support for healing. Used in wound closure and organ repair, they are limited by lower strength and shelf life. Newer formulations combine synthetic or bioactive components to improve performance [6].

Hydrogel-Based Adhesives

Australian research based on mussel‑inspired, dopamine‑functionalised hyaluronic acid hydrogels which rapidly form strong bonds in wet environments, support cell adhesion with controllable degradation [7]. Other work highlights silk fibroin + GelMA composite hydrogels, where protein‑based mechanical strength and photo‑cross‑linkable gelatin chemistry yield materials with enhanced adhesion and structural integrity for tissue repair applications [8].

Biocompatible Coatings for Medical Devices

Untreated surfaces of implantable devices can trigger immune responses, unwanted protein adsorption, and bacterial colonisation. Tailoring surface chemistry and topography improves biocompatibility, reduces inflammation and infection risk, and enhances integration with surrounding tissue, ultimately supporting device function and long-term clinical success.

Polymer-Based Coatings

Australian researchers are advancing polymer coatings for biomedical use, focusing on methods that tailor surface chemistry, functionality and performance. Techniques such as dip coating, spin coating and plasma polymerisation are widely used to apply thin polymer films with controlled thickness and properties to various substrates, including implants and scaffolds [9.] Hydrogels are polymeric networks capable of holding large quantities of solvated hydrophilic drugs. Since the early 1960s they have been considered for controlled release of trapped drugs, both small molecule and macromolecular drugs, through slow diffusion [18].

Antimicrobial Coatings

Australian researchers are developing antimicrobial coatings for medical devices and implants that prevent bacterial adhesion and biofilm formation. Strategies include silver‑based, peptide‑functionalised, polymer‑iodine, and nanocomposite coatings. These coatings aim to enhance biocompatibility, reduce infection risk, and meet biomedical standards, supporting safer and longer-lasting clinical applications [10].

Drug-Eluting Coatings

Australian researchers are advancing drug-eluting coatings for implants like stents, enabling controlled local delivery of therapeutics such as anti-inflammatory, anticancer, or cardiovascular drugs. Techniques include polymer layering, nanoparticle incorporation, and nanostructured surfaces, designed to optimise release kinetics, improve efficacy, reduce systemic side effects, and maintain biocompatibility and long-term device performance [11].

Characterising Adhesives and Coatings: Analytical Methodologies

Rigorous characterisation is crucial for regulatory approval, clinical translation, and quality control, ensuring safety, reproducibility, and reliable performance. Multiple complementary techniques—covering particle size, surface chemistry, mechanics, and degradation—are needed to fully understand material properties, supporting consistent quality and predictable behaviour in complex biological environments.

Measuring surface wettability and the role of surface free energy

A widely used method to assess how liquids interact with a surface is the sessile drop technique This is an optical drop shape analysis technique to assess a solids wettability by measuring the static (drop sits on the surface) or dynamic (drop is increased or reduced) contact angle of a liquid. For example, dental and bone implant materials with different hydrophilic (water-attracting) or hydrophobic (water-repelling) properties can influence how they interact with physiological environments, making the sessile drop method an effective tool for assessing these surface properties. [12].

Optical tensiometry such as with the KRÜSS DSA100 Drop Shape Analyser, make this process highly precise and automated. A small droplet of liquid (often water) is placed on a flat solid surface. The shape of the droplet is observed and analysed, particularly the contact angle—the angle between the liquid–solid interface and the tangent at the liquid surface. A low contact angle (<90°) indicates the surface is hydrophilic and liquid spreads easily. A high contact angle (>90°) means the surface is hydrophobic and liquid beads up.

This method predicts wettability, adhesion, and biocompatibility of surfaces, making it essential for medical implants, coatings, adhesives, and biomaterials. KRÜSS instruments automate image capture and analysis, providing reproducible, high-precision data suitable for research, quality control, and regulatory documentation.

The sessile drop method also provides information on surface free energy (SFE), a key factor in medical device surface treatments. Developers can use this data to optimise adhesive bonding and surface modifications. Materials with high surface free energy and polarity—approaching that of water—tend to enhance biocompatibility, while low SFE surfaces are more hydrophobic and resist wetting or bonding. Hydrophobic prostheses, including plastics or titanium, are often plasma-treated to increase polarity, and contact angle measurements quantify pretreatment success by evaluating polar (e.g., hydrogen bonding, dipole interactions) and dispersive (van der Waals) components.

For temporary implants, excessively high biocompatibility can be undesirable, as strong adhesion complicates removal. In these cases, hydrophobic materials or coatings are preferred, and a high-water contact angle indicates suitability.

Force tensiometry such as with the KRUSS Tensiio is another technique used for assessing biocompatible coatings. The Tensiio uses the Wilhelmy plate method to measure the contact angle of coatings on solid samples (e.g., implants, stents, catheters). This determines if the surface is hydrophilic (water-attracting) or hydrophobic (water-repelling), which is critical for biocompatibility. Tensiio can detect variations in surface tension to check the uniformity of coatings applied to substrates and helps optimise the hydrophilic character of materials (like dental implants) to ensure proper wetting by body fluids, reducing air pockets and improving biocompatibility.

For rapid quality control of coating uniformity on medical device surfaces, handheld systems like the MSA Mobile Surface Analyser enable one-click surface free energy measurements of the material [13]. After quickly inserting and filling a cartridge, wetting behaviour can be measured within seconds by just pressing a button. The determined polarity of the surface gives direct feedback to the effect of pretreatment methods such as plasma treatment.

Particle Size and Colloidal Stability

The Malvern Panalytical Zetasizer Advanced series are standard tools for characterising particle size and colloidal stability in the development of biocompatible implants and coatings. Using Dynamic Light Scattering (DLS) and electrophoretic light scattering (ELS) these analytical instruments measure the hydrodynamic diameter (particle size), polydispersity index (PDI), and zeta potential of nano- and micro-materials to ensure stability, proper drug release, and biocompatibility.

The Malvern Zetasizer series employs Non-Invasive Back Scatter (NIBS) technology enabling measurements across wide concentration ranges, while M3-PALS technology provides precise zeta potential determination indicating formulation stability. Primary mechanisms of instability include aggregation or coagulation, the joining together of one of more particles, and sedimentation or settling. These mechanisms may occur independently, or in combination, as in the case of aggregation followed by associated sedimentation of the resulting larger particles [14]. Zetasizer Ultra offers advanced multi-angle detection (MADLS) which further enhances resolution of complex or multimodal nanoparticle systems, making the Zetasizer Ultra particularly valuable for hybrid or composite adhesive systems.

For higher resolution analysis of polydisperse samples, Nanoparticle Tracking Analysis using instruments like the NanoSight Pro enables particle-by-particle sizing and concentration measurement. For nanoparticle-based coatings, especially those incorporating polymer nanoparticles, or biologically derived components, understanding particle concentration and distribution is critical for dose control and functional consistency. Fluorescence capabilities also allow selective measurement of labelled nanoparticles within complex biological media — a significant advantage when evaluating adhesive systems intended for in vivo applications [15].

Together, the Zetasizer Ultra and NanoSight Pro provide orthogonal, complementary data. DLS offers rapid, bulk measurement of size and stability, while NTA delivers single-particle resolution and accurate concentration analysis.

Microscopy and Morphological Analysis

Understanding the structure and morphology of biocompatible adhesives and coatings is essential for predicting performance, adhesion strength, degradation, and biological response. Imaging techniques provide direct insight into particle shape, surface uniformity, coating thickness, dispersion, and interfacial interactions — supporting both formulation optimisation and quality control.

Two powerful and complementary tools for this purpose are the Morphologi 4-ID from Malvern Panalytical and the Phenom ProX from Thermo Fisher Scientific.

The Morphologi 4-ID combines automated static image analysis with chemical identification using Raman spectroscopy. Automated imaging provides statistically robust shape information on thousands of individual particles. The addition of Raman identification allows chemical verification of specific particle populations within complex mixtures — particularly valuable for multi-component coatings where distribution of active ingredients must be controlled [16].

For detailed surface and interfacial characterisation, scanning electron microscopy (SEM) provides rapid characterisation of coating microstructure, particle distribution, and surface topology at nanometer resolution. Desktop SEM systems such as the Phenom ProX combine high-resolution imaging (< 6 nm) with integrated EDS elemental analysis, providing chemical composition verification alongside structural imaging without the additional costs and complex infrastructure requirements of traditional floor-model SEMs. The rapid time-to-image (< 30 seconds) and intuitive operation enable high-throughput quality control in medical device manufacturing [17].

Formulation Development and Processing

Micropore’s membrane-based technologies can directly support the development of hydrogel-based biocompatible coatings by enabling controlled formation and sizing of hydrogel particles — a key factor in performance and consistency.

Membrane emulsification can form hydrogel droplets as water‑in‑oil emulsions with very uniform size and shape, generating spherical hydrogel particles smaller than ~50 µm with tight size control. This precise control helps produce coatings with predictable hydration, adhesion properties, and surface coverage. Because hydrogels are often used to mimic the extracellular matrix or to deliver actives in biomedical coatings (e.g., wound dressings, tissue engineering scaffolds, or sustained release systems), producing monodisperse hydrogel particles reduces variability and improves reproducibility in coating formulations. The controlled droplet formation also minimises defects and improves stability relative to conventional high‑shear emulsification [18].

Australian Research Spotlight

Australian biomedical engineering research is a rapidly growing, high-impact field focusing on medical devices and tissue engineering and AI driven diagnostics. Major initiatives include personalised 3D-printed implants, neural engineering (bionics), and advanced imaging.

Researchers at UNSW Biomedical engineering are working on developing brain-machine interfaces focused on improving bionic eyes for vision restoration in blind humans as well as developing other devices for chronic pain and inflammatory bowel disease. It is hoped that their work could one day offer dramatic benefits for paralysed individuals to regain use of limbs [19].

At the University of Melbourne, Department of Biomedical Engineering, researchers together with Anatomics – manufacturer of titanium cranio-facial implants – have developed a technique to make polymer-based skull implants more bone-like in their structure, leading to improved outcomes for patients relying on implants to repair head injuries [20].

Harry Perkins Institute of Medical Research [21] in Western Australia has developed biopolymer 3D-printed heart valve technology to be commercialised in Australia to help millions globally suffering from aortic stenosis.

The CSIRO holds the patent and provisional patents in surface modification technology, which is being used in multiple SIEF projects designing coatings for medical devices biocompatibility, hemocompatibility and to minimise foreign body responses [22, 23].

Current Challenges and Future Directions

Biocompatible coatings and tissue adhesives face several persistent challenges in moving from laboratory research to clinical use:

Balancing strong adhesion with low toxicity
Achieving controlled degradation that matches tissue healing rates
Maintaining stability in complex, dynamic biological environments
Incorporating therapeutic agents without compromising mechanical performance
Scaling up manufacturing while meeting strict regulatory requirements

Looking ahead, research is focused on bioinspired wet-adhesion strategies, smart and stimuli-responsive materials, nanostructured designs for improved strength and controlled release, scalable GMP-ready manufacturing, and more predictive characterisation and modelling tools — all aimed at creating safer, more clinically translatable systems.

ATA Scientific’s Commitment to Biomedical Research

At ATA Scientific, we support researchers with proven technologies from leading partners including Malvern Panalytical, KRÜSS, and ThermoScientific — helping ensure critical material properties are understood, controlled, and optimised.

From early-stage formulation through to final product optimisation, comprehensive material characterisation underpins innovation in tissue adhesives and biocompatible coatings. By combining complementary analytical techniques, researchers gain the insights needed to design safer, more effective materials that perform as intended in complex biological environments.

If you’d like to explore how these technologies can support your biomaterials research, our team is here to help—offering expert advice, applications support, and local service every step of the way.

References

[1] https://www.csiro.au/en/research/production/materials/coatings/biocompatible-coatings

[2] https://researchportalplus.anu.edu.au/en/publications/dopamine-modified-hyaluronic-acid-hydrogel-adhesives-with-fast-fo/

[3] https://eprints.qut.edu.au/243011/

[4] https://www.sciencedirect.com/science/article/abs/pii/S0079670021000356

[5] https://www.sciencedirect.com/topics/engineering/cyanoacrylate-adhesive#:~:text=%E2%80%9CBlooming%E2%80%9D%20or%20%E2%80%9Cfrosting%E2%80%9D,cyanoacrylates%20%5B3%2C%207%5D.

[6] https://www.sciencedirect.com/topics/engineering/bioadhesives#:~:text=Adhesives%20and%20Sealants&text=Adhesives%20produced%20by%20marine%20organisms,including%20biocompatibility)%20of%20these%20materials.

[7] https://researchportalplus.anu.edu.au/en/publications/dopamine-modified-hyaluronic-acid-hydrogel-adhesives-with-fast-fo/

[8] https://researchportalplus.anu.edu.au/en/publications/silk-fibroingelma-based-hydrogels-as-a-platform-for-tissue-adhesi/?

[9] https://research.csiro.au/bmtf/services/surface-engineering/?

[10] https://www.rmit.edu.au/news/all-news/2025/jun/antibacterial-resilin?

[11] https://pubs.rsc.org/en/content/articlehtml/2025/nr/d5nr00436e?