Chlorhexidine/losartan ionic pair binding and its nanoprecipitation: physico-chemical characterisation and antimicrobial activity

• Published in: Supramolecular chemistry Vol. 24; no. 3; pp. 204 - 212
• Main Authors: Denadai, Ângelo M.L., de Oliveira, André M., Daniel, Izabela M.P., Carneiro, Luan A., Ribeiro, Kherolayne C., Beraldo, Heloísa de O., da Costa, Kelen J.R., da Cunha, Vivianne C., Cortés, Maria E., Sinisterra, Rubén D.
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis Group 01.03.2012; Taylor & Francis Ltd
• Subjects: antimicrobial; Antimicrobial agents; Bacteriology; chlorhexidine; hydrophobic ion paring; losartan; Nanoparticles
• ISSN: 1061-0278; 1029-0478
• DOI: 10.1080/10610278.2011.642101

Chlorhexidine is a widely used, di-cationic, broad-spectrum antimicrobial agent and losartan is a well-known, anionic-specific antagonist of AT1 renin-angiotensin receptor that acts as an anti-hypertensive agent. The combination of these molecules gives a chlorhexidine di-losartanate (ClxLos 2 ) hydrophobic ion pair that spontaneously aggregates into nanoparticles (NPs). This work investigated the formation of ClxLos 2 NPs using the analysis of the solid state by fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry and scanning electron microscopy and in aqueous environment by calorimetric, zeta potential and dynamic light scattering titrations. Furthermore, to demonstrate the potential antimicrobial activity of ClxLos 2 , in vitro antibacterial tests were conducted against Staphylococcus aureus (ATCC 27664), Streptococcus viridans (ATCC 11563) and Enterococcus faecalis (ATCC 14508). Based on these studies, it is proposed that ClxLos 2 could be used for controlled drug release based on ionic dissociation during dilution, thereby avoiding the use of any solid matrix.