title: Kinetics of protein-protein complex coacervation and biphasic release of salbutamol sulfate from coacervate matrix.
abstract: Turbidimetric titration was used to initiate associative intermolecular interactions between a pair of protein molecules, gelatin-A and gelatin-B, having complementary charges that led to pH-induced liquid-liquid phase separation and the formation of complex coacervate. The stoichiometric binding ratio was found to be [gelatin-A]/[gelatin-B]=3:2. The size of soluble intermolecular aggregates present in the supernatant exhibited interesting time-dependent coacervation because of residual electrostatic interactions. Dynamic light scattering and turbidity studies provided a systematic account of coacervation behavior. Rheology studies attributed the softening of the coacervate matrix to the presence of encapsulated salbutamol sulfate. The in vitro drug release kinetics was probed in simulated gastric fluid medium at physiological temperature (37 degrees C), which showed biphasic behavior. The initial release kinetics exhibited an exponential growth to saturation behavior, followed by a slower logarithmic release process.
authors.affiliation: Department of Chemistry, St. Stephens College, Delhi, India.
authors.forename: Ananya
authors.initials: A
authors.lastname: Tiwari
authors.forename: Sonal
authors.initials: S
authors.lastname: Bindal
authors.forename: H B
authors.initials: HB
authors.lastname: Bohidar
mesh_terms: D000420:Albuterol / Q000737:chemistry*; D005780:Gelatin / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D009391:Nephelometry and Turbidimetry; D010316:Particle Size; D011485:Protein Binding; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors
chemical_list: D005780:Gelatin; D000420:Albuterol