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In soft tissue replacement, hydrophilic, flexible, and biocompatible materials are used to reduce wear and coefficient of friction. This study aims to develop and evaluate a solid/liquid triborheological system, polyvinyl alcohol (PVA)/hyaluronic acid (HA), to mimic conditions in human synovial joints. Hydrogel specimens prepared via the freeze–thawing technique from a 10% (w/v) PVA aqueous solution were cut into disc shapes (5 ± 0.5 mm thickness). Compression tests of PVA hydrogels presented a Young’s modulus of 2.26 ± 0.52 MPa. Friction tests were performed on a Discovery Hybrid Rheometer DHR-3 under physiological conditions using 4 mg/mL HA solution as lubricant at 37 °C. Contact force was applied between 1 and 20 N, highlighting a coefficient of friction change of 0.11 to 0.31 between lubricated and dry states at 3 N load (angular velocity: 40 rad/s). Thermal behavior was evaluated by differential scanning calorimetry (DSC) in the range of 25–250 °C (5 °C/min rate), showing an endothermic behavior with a melting temperature (Tm) around 231.15 °C. Scanning Electron Microscopy (SEM) tests showed a microporous network that enhanced water content absorption to 82.99 ± 1.5%. Hydrogel achieved solid/liquid lubrication, exhibiting a trapped lubricant pool that supported loads, keeping low coefficient of friction during lubricated tests. In dry tests, interstitial water evaporates continuously without countering sliding movement friction.

Density functional theory calculations have been used to elucidate structural parameters of pristine cardiac Troponin I and its interaction with carbon nanomaterials. In this case, zigzag single-walled carbon nanotubes and graphene sheets were selected. Troponin I interacted horizontally (leusine terminal) and vertically (lysine terminal) with the nanomaterials. Cohesion and binding energies, band gaps, and charge transfer for the systems were obtained. Cohesion for troponin I supported on graphene and single-walled carbon nanotube in the horizontal position was found to be the most viable system. Binding for the interaction between troponin I and a nanotube in the horizontal position was found to be the most stable with a value of 0.002 eV that increases to 0.004 eV with a van der Waals correction. Furthermore, the density of states exhibits an improvement in band gap for graphene sheets, and finally, a higher charge transfer was reported for troponin I in its horizontal form supported on a zigzag single-walled carbon nanotube.