Influence of the feed composition on the production of polylysine-Indomethacin microparticles by spray-drying

CESCHAN NE; BUCALÁ V; RAMÍREZ RIGO MV

Córdoba

Congreso; 3° Reunión Internacional de Ciencias Farmacéuticas (RICiFa 2014); 2014

Universidad Nacional de Córdoba

Indomethacin (IN) reduces pain and inflammation in osteoarthritis, rheumatoid arthritis and tendinitis. Inhaled administration was proposed to overcome gastrointestinal side effects. Spray drying (SD) is an adequate technique to manufacture inhalable powders. The aim of this work is to produce a novel material constituted by IN (model acid drug) and polylysine (PL, cationic polylectrolyte) evaluating relationships process-product quality. PL was combined with IN to obtain (PL-IN)x Y% solutions with different neutralization degrees (25-50-75%, identified with subscripts) and total solid contents (identified as percentages, 1.3-1.6-2.6%w/v). The amount of drug in the solutions, drying performance and residual moisture of the powders were assayed. IN content in the product and glass transition temperature (Tg) of the material were analyzed. Drug content in the feed was in accordance with the amount of IN used for preparing the solutions, except for the (PL-IN)751.6% solution where partial precipitation of the drug was detected. This behavior was associated to the poor solubility and high hydrophobicity of IN. SD yields were adequate for lab scale. At fixed feed solid content, yields decreased from 54.38- 46.23% when the neutralization degree of PL changed from 25-75%. When solid content of (PLIN) 50 was modified from 1.3-1.6%, yield was around 50% but it substantially increased up to 67% when solid content was 2.6%. Residual moisture was low (3.504.84%) indicating that drying was efficient. Drug content in the product was in good agreement with the amount of IN in the feed. Tg values decreased from 138.50-126.07 °C with the IN content in the product. It is due to the plasticizing effect of the drug on the polymer structure. Stickiness in the chamber could explain the yield behavior of the tested samples. Feed solid content and neutralization degree were variables that modify the process yield and product quality.