Chitinosans as tableting excipients for modified release delivery systems

The term 'chitinosans' embraces the spectrum of acetylated poly(N-glucosami nes) ranging from chitin to chitosan. Chitinosans (I), at acidic pH, have p rotonated amines which can interact with oppositely charged drug ions and, thereby, modify drug release from drug delivery systems. Tablets were compr essed from a physical mixture containing salicylic acid (II) as the model d rug, I, and magnesium stearate. Five commercial I compounds, varying in deg ree of deacetylation and molecular weight, were selected. Tablets were comp ressed at 5000, 10000, and 15000 psig using a Carver and a single punch tab let press. The differential scanning calorimetry thermograms provided evide nce of I-Il interaction in the powder blend. Analysis of variance (ANOVA) i ndicated that the compression pressure did not significantly affect the cru shing strength (CS) or the release profile of II from the I-matrix tablets (P > 0.05). Furthermore, the ANOVA also indicated that the tablet press use d during manufacture did not affect the above properties (P > 0.05); howeve r, the chitinosans significantly affected the CS as well as the release pro file of II from I-matrix tablets (P < 0.05). This study provides further ev idence for the use of commercial I compounds as excipients for use in modif ied release drug delivery systems. (C) 1999 Elsevier Science B.V. All right s reserved.