Inorganic Fullerene Coating For Medical Devices

The Need

Implantable or insertable medical devices must be biocompatible and possess specific mechanical properties depending on their designated use. In addition, they should also be resistant to potential damage by the physiological environment to ensure their long-lasting effectiveness. In the case of urethral medical devices (e.g., catheters), their exposure to calcium and phosphate ions from the urine results in the formation of crystals on the biomaterial surface, a process known as encrustation. Encrustation may cause infections and harm the medical device's functionality, resulting in its frequent replacement, which is inconvenient to the patient and costly. Also, excessive friction severely compromises the insertion and retrieval of medical devices from narrow constrictions in the body, and leads to pain and morbidity of the paitent. In this context, one of the field's major goals is to search for new products that would generate less friction during insertion and retrieval of catheters, endoscopes and laparoscopes through narrow natural and purposely cut constrictions in the human body. Additionally, coating of endodontic files (EFs) used for root canal treatment can benefit from this technology as well. Finding a way to reduce file breakage during root canal treatment would greatly influence the costs of treatment and the prognosis of treated teeth stages and conditions. Therefore, there is a need for an efficient, general coating method to increase lubricity, thus preventing encrustation and reducing friction.

The Solution

Prof. Reshef Tenne and his team developed a novel method for coating medical devices to reduce friction and increase lubricity using inorganic fullerene-like nanoparticles (IF?WS2, IF-MoS2) 1,2

Technology Essence

Fullerene-like nanoparticles (i.e., IF-WS2, IF-MoS2) are deposited on top of medical devices and change their surface properties dramatically. These nanoparticles produce coating films with a relatively small tendency to agglomerate. This architecture, together with the low affinity of the nanoparticles towards the environment (due to closed caged moieties which lack dandling bonds), results in their superior lubricity.

Applications and Advantages

Applications

• Coating implantable or insertable medical devices such as stents; catheters; dialysis tubes; cannulas; and sutures

Advantages

Non-toxic

Cheap

• Can be easily applied to existing medical devices
• Biocompatible – Initial tests in animals suggest safety from toxic effects

References

1. Adini AR, Feldman Y, Cohen SR, et al. Alleviating fatigue and failure of NiTi endodontic files by a coating
containing inorganic fullerene-like WS 2 nanoparticles. J Mater Res. 2011;26(10):1234-1242. doi:10.1557/jmr.2011.52 [1]
2. Goldbart O, Yoffe A, Cohen SR, et al. New Deposition Technique for Metal Films Containing Inorganic FullereneLike (IF) Nanoparticles. ChemPhysChem. 2013;14(10):2125-2131. doi:10.1002/cphc.201201003 [2]