Optimization Formula and Stability of Rifampicin–Pectin Pulmospheres Produced by Aerosolization Technique: Effect of Polymer Concentration

Tuberculosis is a global challenge notable in developing countries due to its high mortality rate and significant health problems. Rifampicin, semi-synthetic antibiotic effective against tuberculosis, undergoes first-pass metabolism in the liver when administered orally, resulting in low drug concentrations in the lungs. This can potentially reduce its bactericidal activity, leading to treatment failure, relapse, and bacterial resistance. One strategy is to administer the drug directly into the lungs by inhalation.This approach can improve the drug's bioavailability, enable controlled release, reduce toxicity, and enhance patient compliance. The purpose of this study is to investigate how the concentration of pectin affects the properties and stability of inhalable rifampicin–pectin pulmospheres. These pulmospheres, produced using the aerosolization technique, were prepared using different polymer concentrations of 1.5% (F1), 1.75% (F2), and 2% (F3). The physical characteristics of pulmospheres were assessed, including organoleptic, yield, moisture content (MC), drug loading, entrapment efficiency, and morphology. This study found that the yield was 53.23% ± 5.85 to 94.58% ± 3.06; the MC was 2.89% ± 0.66 to 3.44% ± 0.44; the drug loading was 0.43% ± 0.02 to 2.09% ± 0.58; and the entrapment efficiency was 7.71% ± 0.33 to 72.18% ± 16.78. Spherical and smooth pulmospheres were found. Formula 3 is the best rifampicin–pectin pulmospheres demonstrating superior physical characteristics and the ability to maintain stability up to day 28. Increasing the pectin concentration led to enhance drug loading, encapsulation efficiency and stability, suggesting their potency as an effective pulmonary delivery system for tuberculosis treatment.