Evaluation of Drug Sorption to PVC- and Non-PVC-based Tubes in Administration Sets Using a Pump

Understanding and Characterizing the Drug Sorption to PVC and PE Materials

Characterizing the sorption of drugs onto polyvinylchloride (PVC) and polyethylene (PE) materials in terms of thermodynamic adsorption properties and atomistic details (local arrangements, orientation, and diffusion) is fundamental for the development of alternative materials that would limit drug sorption phenomena and plasticizer release. Here, a combination of experiments and sophisticated calculations of potential of mean forces are carried out to investigate the sorption of paracetamol and diazepam to PE and PVC surfaces. The simulated Gibbs free energies of adsorption are in line with the experimental interpretations. The polymer-drug-water interface is then characterized at the molecular scale by an in-depth investigation of local properties such as density, orientation, and diffusion.

The role of Piezo1 in conventional aqueous humor outflow dynamics

Controlling intraocular pressure (IOP) remains the mainstay of glaucoma therapy. The trabecular meshwork (TM), the key tissue responsible for aqueous humor (AH) outflow and IOP maintenance, is very sensitive to mechanical forces. However, it is not understood whether Piezo channels, very sensitive mechanosensors, functionally influence AH outflow. Here, we characterize the role of Piezo1 in conventional AH outflow. Immunostaining and western blot analysis showed that Piezo1 is widely expressed by TM. Patch-clamp recordings in TM cells confirmed the activation of Piezo1-derived mechanosensitive currents. Importantly, the antagonist GsMTx4 for mechanosensitive channels significantly decreased steady-state facility, yet activation of Piezo1 by the specific agonist Yoda1 did not lead to a facility change. Furthermore, GsMTx4, but not Yoda1, caused a significant increase in ocular compliance, a measure of the eye's transient response to IOP perturbation. Our findings demonstrate a potential role for Piezo1 in conventional outflow, likely under pathological and rapid transient conditions.

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Piezo1 is functionally expressed in the TM, the most important tissue controlling IOP

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Suppression of mechanosensitive channel leads to a significant decrease in facility

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Our data suggest a role for Piezo in pathological situations and rapid IOP transients