Lubricating Medical Devices with Fullerene-Like Nanoparticles

Anastasiya Sedova, Materials and Interfaces, Weizmann Institute of Science, Rehovot, Israel

Invasive medical procedures, encountered in such fields as urology, gastroenterology, etc. make use of plastic/metallic devices, which go through narrow constrictions, in the human body, in order to diagnose medical diseases. The applied force for the insertion/extraction of the device from the human cavities must overcome the inserted device-surface human-tissue interactions. In daily practice, a commercial water-based gel is applied on the endoscope/catheter surface, in order to facilitate its entry to the cavities.

In the present work, a new solid-state lubricant has been added to the gel, in order to reduce the device-soft tissue interaction and alleviate the potential damage to the soft tissue. For that purpose, a urethra model was used, which allowed a quantitative assessment of the applied force for extraction of the endoscope and catheters from a soft polymer-based ring. It is shown that the addition of MoS₂ nanoparticles with fullerene-like structure (IF-MoS₂) and in particular rhenium-doped nanoparticles (Re: IF-MoS₂) to the commercial gel applied on the devices surfaces reduced the friction substantially. The Re:IF-MoS₂ showed better results than the IF-MoS₂ and both performed better than the gel alone or gel made with microscopic platelets of WS₂/MoS₂. The mechanism of friction reduction is attributed to the fullerenes ability to roll/slide and to act as separator between the active surfaces of the model [1].

[1] Goldbart, O.; Sedova, A.; Yadgarov, L.; Rosentsveig, R.; Shumalinsky, D.; Lobik, L.; Wagner, H. D.; Tenne, R., Lubricating Medical Devices with Fullerene-Like Nanoparticles. Tribology Letters 2014, 55 (1), 103-109.