Thermosensitive In Situ Liposomal Gels Loaded With Antimicrobial Agent for Oral Care in Critically Ill Patients

Abstract

Aim: A novel thermosensitive in situ gel loaded with meropenem (MP) liposomes was designed to improve retention in the oral cavity as a prophylactic measure to prevent ventilator-acquired pneumonia in critically ill patients. Methodology & results: Meropenem liposomes were incorporated into poloxamer 407 gels and gamma irradiated. Mean size of liposome was 247 nm, polydispersity index < 0.3 and zeta potential >-25 mV; properties remained unaltered even post sterilization. Permeation study revealed that 75.26% and 34% of MPs were released from MP in situ gel and MP in situ liposomal gel, respectively. The relation between viscosity (cp) and shear rate (1/s) indicate that in situ gels exhibited non-Newtonian behavior at 37°C. The study using Pseudomonas aeruginosa confirmed the antimicrobial activity of meropenem. Conclusion: Prolonged in situ residence, because of rapid gelation process enables an easy administration of meropenem as liposomal suspension in critically ill patients.

Rheological Properties Study of Oral Hydrogels Containing Phenobarbital for a Potiential Pediatric Use

“…On the other hand, the major interactions responsibles to formation of the physical hydrogels are hydrophobic interactions and hydrogen bonds reflecting their strengh, their density and their viscosity [23,24]. In this study, we noticed that the viscosity of the hydrogels decreased as the shear rate and time increased for all formulations under applied a shear stress.…”

“…In this study, we noticed that the viscosity of the hydrogels decreased as the shear rate and time increased for all formulations under applied a shear stress. It reflects the characteristics of a non-Newtonian behavior [25] with the shear thinning and thixotropic type [15,23]. This result is linked to the dissociated reticulation networks formed into the hydrogels due to theirs chains relaxation depending of time [24] but also to the reorientation of particulate entities in the direction of flow and under the effect of shear and hydrodynamic forces [9,26].…”