title: Investigating the effects of surfactants on the size and hydrolytic stability of poly(adipic anhydride) particles.
abstract: The present study investigates the effects of surfactants (<0.01% v/v) on the size and hydrolytic stability of poly(adipic anhydride) (pAA) micro- and nanospheres fabricated using a modified phase inversion technique. Overall, surfactants increased the output yield by roughly 20%. Lecithin produced the greatest reduction in the volumetric particle size (dvol) compared to particles fabricated with no surfactant (dvol = 530 +/- 300 nm and 2.2 +/- 1.1 microm, respectively). In addition, sorbitan monooleate produced spheres with smaller numeric diameters (dnum) than the control but appeared to induce aggregation (dvol = 7.7 +/- 12.5 microm). The dnum and dvol were not dependent on the hydrophobicity of the surfactant (R2 = 0.36 and 0.03, respectively) or the apparent surface tension of the non-solvent (NS) phase (R2 = 0.44 and 0.04, respectively). In addition, quantitative DSC and FT-IR analysis confirmed that altering the particle size could also influence the hydrolytic stability of pAA.
authors: Department of Molecular Pharmacology, Physiology and Biotechnology, Brown University, Providence, Rhode Island 02912, USA.
authors: A Peter
authors: AP
authors: Morello
authors: Natalie
authors: N
authors: Forbes
authors: Edith
authors: E
authors: Mathiowitz
mesh_terms: D000272:Adipates / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D004339:Drug Compounding; D016503:Drug Delivery Systems; D004355:Drug Stability; D006868:Hydrolysis; D054709:Lecithins; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D008863:Microspheres; D054118:Nanospheres; D010316:Particle Size; D011108:Polymers / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013500:Surface Tension; D013501:Surface-Active Agents
chemical_list: D000272:Adipates; D054709:Lecithins; D011108:Polymers; D013501:Surface-Active Agents; C504784:poly adipic anhydride