Liposomal-benzocaine gel formulation: correlation between in vitro assays and in vivo topical anesthesia in volunteers

Author(s):Show less -

Franz-Montan, Michelle ^{[1, 2]} ; Saia Cereda, Cintia Maria ^[2] ; Gaspari, Adele ^[3] ; Goncalves da Silva, Camila Morais ^[2] ; de Araujo, Daniele Ribeiro ^{[4, 2]} ; Padula, Cristina ^[3] ; Santi, Patrizia ^[3] ; Narvaes, Eliene ^[5] ; Novaes, Pedro Duarte ^[5] ; Groppo, Francisco Carlos ^[1] ; de Paula, Eneida ^[2]

Affiliation

^[1] Univ Estadual Campinas, Piracicaba Dent Sch, Dept Physiol Sci, Sao Paulo - Brazil

^[2] Univ Estadual Campinas, Inst Biol, Dept Biochem, Sao Paulo - Brazil

^[3] Univ Parma, Dept Pharm, I-43100 Parma - Italy

^[4] Fed Univ ABC, Human & Nat Sci Ctr, Sao Paulo - Brazil

^[5] Univ Estadual Campinas, Piracicaba Dent Sch, Dept Morphol, Sao Paulo - Brazil

• Document type: Journal article
• Source: Journal of Liposome Research; v. 23, n. 1, p. 54-60, MAR 2013.
• Web of Science Citations: 15

Abstract

The aim of the present study was to characterize a liposome-based benzocaine (BZC) formulation designed for topical use on the oral mucosa and to evaluate its in vitro retention and permeation using the Franz-type diffusion cells through pig esophagus mucosa. To predict the effectiveness of new designed formulations during preclinical studies, a correlation between in vitro assays and in vivo efficacy was performed. Liposomal BZC was characterized in terms of membrane/water partition coefficient, encapsulation efficiency, size, polydispersity, zeta potential, and morphology. Liposomal BZC (BL10) was incorporated into gel formulation and its performances were compared to plain BZC gel (B10) and the commercially available BZC gel (B20). BL10 and B10 presented higher flux and retention on pig esophagus mucosa with a shorter lag time, when compared to B20. BZC flux was strongly correlated with in vivo anesthetic efficacy, but not with topical anesthesia duration. The retention studies did not correlate with any of the in vivo efficacy parameters. Thus, in vitro permeation study can be useful to predict anesthetic efficacy during preclinical tests, because a correlation between flux and anesthetic efficacy was observed. Therefore, in vitro assays, followed by in vivo efficacy, are necessary to confirm anesthetic performance. (AU)

• FAPESP's process: 06/00121-9 - New formulations for the controlled release of local anesthetics in dentistry: from development to clinical tests
• Grantee: Eneida de Paula
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 09/08860-3 - Transdermal permeation and biocompatibility studies on gel formulations of benzocaine encapsulated in elastic and conventional liposomes
• Grantee: Michelle Franz Montan Braga Leite
• Support Opportunities: Scholarships in Brazil - Post-Doctoral