Nanocellulose: A Bright Future for Medical Devices?

Nanocellulose is emerging as a transformative material in the medtech sector, offering an exceptional combination of biocompatibility, sustainability, and mechanical versatility. Derived from natural sources like wood, this biomaterial is already being integrated into a range of innovative applications. With increasing demand for eco-friendly and non-animal-derived materials, nanocellulose is poised to revolutionize medical device design and manufacturing.

What Is Nanocellulose?

Nanocellulose is a cellulosic material with at least one dimension smaller than one micrometer (Figure 1). All types of nanocellulose have this in common, but there is very little other standardization. This can make research results found in the literature confusing. For example, consider water; you can take water from the sea and use it to mix cement, but you would not drink seawater until it was purified and tested. Similarly, cellulose and nanocellulose have many possible applications depending on their level of refinement and testing. 

Nanocellulose is versatile and can be extracted from various sources. Plants provide the most abundant supply, but other sources include agricultural biomass, bacteria, algae, and even marine invertebrates like tunicates. Among all nanocellulose options, plant-derived nanocellulose has gained the most attention as well as the most patents in the medical field.

Spaghetti or Rice?

Nanocellulose can be processed mechanically into nanofibers (long, spaghetti-like structures) often called cellulose nanofibrils or nanofibrillated cellulose. Alternatively, nanocellulose can be processed chemically into nanocrystals (short, rice-like structures) often called cellulose nanocrystals or nanocrystalline cellulose. 

Nanocellulose possesses extraordinary properties such as high strength, tunability, and a large surface area. The shape has a profound effect on the properties, such as gelation, sedimentation, and toxicity. 

• Nanofibrillated cellulose (NFC): Known for flexibility. NFC with long fibers and a narrow diameter has unique shear thinning and water retention properties. NFC forms injectable hydrogels and thus is suited not only for wound care but also for tissue scaffolding and drug delivery.
• Cellulose Nanocrystals (CNC): Known for rigidity and optical properties. CNC is used in reinforcing composites and hygiene products. 

The Growth of Nanocellulose Interest 

Over the past two decades, the field of nanocellulose has experienced a surge in research activity and patent filings (Figure 2). With over 50,000 patents worldwide, its applications extend far beyond traditional industries into advanced sectors such as life sciences and medicine.

The growing interest among medical device manufacturers is fueled by nanocellulose’s ability to meet stringent biocompatibility and performance standards. Recent advancements have also addressed challenges such as variability and scale-up.

Nanocellulose for Medical Devices 

The unique properties of nanocellulose—biocompatibility, tunability, and mechanical stability—underpin its integration into the medical device sector. From wound healing to drug delivery systems, nanocellulose offers diverse solutions to long-standing challenges in healthcare.¹ In particular, when NFC is processed into a hydrogel, it is temperature stable, has shear-thinning properties, and is easy to inject, making it ideal for non-invasive delivery into the body. Plant-derived nanocellulose-based hydrogels that have no additional components added also show good biocompatibility in pre-clinical trials with minimal risk of inducing systemic toxicity or fibrotic capsule formation. 

Wound Healing

Nanocellulose-based hydrogels have been successfully used as wound dressings, particularly for donor site treatments. The reconstituted hydrogel in the dressing promotes healing by maintaining a moist environment, reducing inflammation and the need for dressing changes. This makes them ideal for treating burns and surgical wounds as they provide an effective barrier while accelerating tissue regeneration.

Beyond passive dressings, research is exploring the use of nanocellulose for active wound care. The material’s tunability allows researchers to incorporate antimicrobial agents or growth factors. For example, hydrogels infused with these additional active components are being developed to enhance healing in chronic wounds, such as diabetic ulcers.² 

Orthopedic Implants

Nanocellulose’s mechanical strength and stability make it suitable for orthopedic applications. The rigidity of nanocellulose fibers, combined with their injectability, can enhance the longevity and performance of implants. It offers the potential for long-term durability for load-bearing devices.

Implantable Scaffolds

Tissue engineering presents one of the most exciting frontiers for nanocellulose in medical applications. Its structure mimics the extracellular matrix, fostering an ideal environment for cell growth and differentiation.³ For example, in cartilage regeneration, nanocellulose scaffolds can replicate the natural supportive framework of cartilage tissue. This not only improves cell adhesion and proliferation but also paves the way for regenerative solutions in areas with limited healing capacity, such as the knee. Such advancements hold immense promise for treating osteoarthritis and other degenerative conditions.⁴

Drug Delivery Systems

Nanocellulose excels as a drug delivery medium, thanks to its capacity for controlled therapeutic release.⁵ By adjusting the material’s concentration or form, researchers can fine-tune how quickly or slowly drugs are released into the body. This offers designers an alternative to conventional carriers, which often decompose too quickly or create byproducts harmful to the patient. Furthermore, nanocellulose hydrogels can encapsulate sensitive drug compounds, safeguarding their efficacy throughout the delivery process. This makes them particularly effective for localized treatments, where precision is critical. 

Currently, nanocellulose is well-suited for topical use and as permanent drug delivery implants, however, in vivo data also shows great promise for nanocellulose for short-term drug delivery. In this case, further development and clinical validation of enzyme mixes is still required. 

Improving Outcomes and Reducing Costs

Whether used as a wound dressing, implantable scaffold, or drug carrier, nanocellulose can significantly improve patient outcomes. The material’s stability reduces the need for repeated interventions, lowering overall healthcare costs. The biocompatibility of animal-free nanocellulose minimizes the risk of adverse immune reactions, reducing patient complications and hospital readmission rates. For healthcare systems facing increasing economic and regulatory pressures, nanocellulose represents an adaptable, cost-effective solution.

The Future of Nanocellulose

Nanocellulose holds immense potential to transform the medical device sector, offering superior biocompatibility, mechanical performance, and sustainability compared to conventional materials. From wound care to orthopedic implants, this versatile animal-free biomaterial promises to improve both patient outcomes and healthcare efficiency. As the industry continues to innovate and refine its capabilities, nanocellulose is likely to inspire the next generation of medical devices. We expect to see new clinical trials for nanocellulose-based hydrogels as medical devices, and continued research in developing implants from nanocellulose with controllable degradation, bioinks, and 3D printing applications for personalized medicine and advanced drug delivery for complex therapies.

Looking ahead, its role in fostering greener, more effective healthcare solutions is truly exciting. With continued advancements in product development and regulatory approvals, nanocellulose’s bright future in medical devices is just beginning.

References

¹ tinyurl.com/mpo250161
² tinyurl.com/mpo250162
³ tinyurl.com/mpo250163
⁴ tinyurl.com/mpo250164
⁵ tinyurl.com/mpo250165

Dr. Johana Kuncová-Kallio is the director at UPM Biomedicals, part of UPM-Kymmene Corporation, renowned as the first company globally to produce plant-based nanocellulose in compliance with ISO 13485 standards. With over 25 years of experience in the bio-nano worlds, Dr. Kuncová-Kallio has developed and commercialized cutting-edge technologies for the medical device industry, in vitro diagnostics, in vitro testing, biosensors, and cell and tissue engineering.