pH-sensitive niosomes: Effects on cytotoxicity and on inflammation and pain in murine models

Abstract

pH-sensitive nonionic surfactant vesicles (niosomes) by polysorbate-20 (Tween-20) or polysorbate-20 derivatized by glycine (added as pH sensitive agent), were developed to deliver Ibuprofen (IBU) and Lidocaine (LID). For the physical-chemical characterization of vesicles (mean size, size distribution, zeta potential, vesicle morphology, bilayer properties and stability) dynamic light scattering (DLS), small angle X-ray scattering and fluorescence studies were performed. Potential cytotoxicity was evaluated on immortalized human keratinocyte cells (HaCaT) and on immortalized mouse fibroblasts Balb/3T3. In vivo antinociceptive activity (formalin test) and anti-inflammatory activity tests (paw edema induced by zymosan) in murine models were performed on drug-loaded niosomes. pH-sensitive niosomes were stable in the presence of 0 and 10% fetal bovine serum, non-cytotoxic and able to modify IBU or LID pharmacological activity in vivo. The synthesis of stimuli responsive surfactant, as an alternative to add pH-sensitive molecules to niosomes, could represent a promising delivery strategy for anesthetic and anti-inflammatory drugs.

Keywords:

• pH-sensitive niosomes
• lidocaine
• ibuprofen
• cytotoxicity
• anti-nociceptive/anti-inflammatory activity

Acknowledgements

We thank T. Narayanan and ID02 beamline staff (ESRF) for technical support. This work was supported by Italian Institute of Technology (IIT) Center for Life Nano Science@Sapienza and the NanoMED project of the JRC Institutional program.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.