RETRACTED ARTICLE: The Influence of Sodium Hyaluronate, l-Leucine and Sodium Taurocholate on the Nebulization of Aqueous Betamethasone-17-Valerate Suspensions

Abstract

Abstract. The purpose of this research was to evaluate the variables that are suggested to influence the adsorption of the hydrophilic hyaluronic acid (HA) onto the surface of the hydrophobic betamethasone-17-valerate (BV) particles in order to formulate a nebulizable suspension. The adsorption of HA from aqueous solutions (0.04% to 0.16%, w/v) to a fixed BV concentration (0.04%, w/v) under different experimental conditions, was investigated. The method of preparation of HA-BV suspensions involved suspending BV particles either in the hydrated HA solution (method 1) or in water followed by addition of solid HA (method 2). Other variables like the time required for the adsorption to complete and temperature at which adsorption is carried out were studied. The nebulization of the suspensions was tested via an air jet nebulizer connected to a twin stage impinger. In order to improve the nebulization behavior of the optimized suspension, L-leucine or sodium taurocholate was incorporated in increasing concentrations (0.01-0.04%, w/v). The optimized suspension, having a nebulization efficiency of 33.75%, was achieved following the adsorption of HA (0.1%, w/v) onto BV particles adopting method 2 of preparation and extending for three days at 4°C. Incorporation of either l-leucine or sodium taurocholate significantly decreased the aggregate size of the optimized suspension and consequently caused significant increases in the nebulization efficiency to reach 46.87% and 56.25%, respectively.

The function and performance of aqueous aerosol devices for inhalation therapy

“…Jet nebulization of nanoparticle dispersions of deoxyribonuclease I (DNase I) showed similar results, while greater than 50% activity of the protein is maintained . Importantly, the nebulization performance of suspensions using jet nebulizers is also dependent on formulation properties, with different excipients and methods of preparation providing rather variable drug deposition patterns . In addition, drug nanoparticle aggregation may also occur during jet nebulization …”

Alternatives to conventional suspensions for pulmonary drug delivery by nebulisers: A review

“…For example, addition of l-leucine or sodium taurocholate has been claimed to increase the efficiency of nebulisation in a suspension containing betamethasone-17-valerate and hyaluronic acid. 18 …”