Evaluating the effect of sodium alginate and sodium carboxymethylcellulose on pulmonary delivery of levofloxacin spray-dried microparticles

Background

Patients with cystic fibrosis commonly suffer from lung infections caused by Pseudomonas aeruginosa. Recently, the Levofloxacin (LVF) nebulizing solution (Quinsair®) has been prescribed for the antimicrobial management. The sustained-release (SR) dry powder formulation of LVF is a convenient alternative to Quinsair®. It has the potential to enhance patient convenience and decrease the likelihood of drug resistance over time.

Objective

In this paper, we set forth to formulate and evaluate the potential application of sodium alginate (SA) and sodium carboxymethylcellulose (SCMC) for sustained pulmonary delivery of LVF.

Methods

The spray-dried (SD) LVF microparticles were formulated using SCMC and SA along with L-leucine (Leu). The microparticles were analyzed in terms of particle size, morphology, x-ray diffraction (XRD), in-vitro drug release, and aerodynamic properties. Selected formulations were further proceeded to short-term stability test.

Results

The polymer-containing samples displayed process yield of 33.31%–39.67%, mean entrapment efficiency of 89% and volume size within the range of 2–5 μm. All the hydrogel microparticles were amorphous and exhibited rounded morphology with surface indentations. Formulations with a drug-to-excipient ratio of 50:50 and higher, showed a 24-h SR. The aerodynamic parameters were fine particle fraction and emitted dose percentage ranging between 46.21%–60.6% and 66.67%–87.75%, respectively. The short-term stability test revealed that the formulation with a 50:50 drug-to-excipient ratio, containing SA, demonstrated better physical stability.

Conclusion

The selected formulation containing SA has the potential to extend the release duration. However, further enhancements are required to optimize its performance.

Graphical abstract