title: Aminophylline targeting to lung: optimization of the size and drug loading of albumin microspheres.
abstract: Aminophylline, a bronchodilator, was considered a suitable drug for targeting to the lung to treat emphysema. Factorial concept was utilized to optimize the size and drug loading of microspheres suitable for targeting. Aminophylline-loaded albumin microspheres were prepared by heat denaturation adjusting the manufacturing variables, namely albumin concentration, drug concentration, water-oil phase ratio and stirring rate at low and high levels. For two levels of the four variables the experimentation was performed in 16 batches. A good yield of well-defined microspheres of the size range, 2-30 microns, were obtained from all the batches. The drug loading was found maximum (36.33 per cent) in batch XV of microspheres prepared with low albumin concentration, high drug concentration, low water-oil phase ratio and low stirring rate. The least number (13 per cent) of microspheres of batch XV were below 7 microns and the remaining 87 per cent were above this size. Considering the payload and size, microspheres of batch XV were found suitable for targeting to the lung.
authors.affiliation: Department of Pharmaceutics, Banaras Hindu University, Varanasi, India.
authors.forename: K P
authors.initials: KP
authors.lastname: Tripathi
authors.forename: J
authors.initials: J
authors.lastname: Singh
mesh_terms: D000418:Albumins; D000628:Aminophylline / Q000008:administration & dosage* / Q000737:chemistry; D002626:Chemistry, Pharmaceutical / Q000379:methods; D004646:Emphysema / Q000188:drug therapy; D006801:Humans; D008168:Lung / Q000378:metabolism*; D008863:Microspheres; D009928:Organ Specificity; D010316:Particle Size
chemical_list: D000418:Albumins; D000628:Aminophylline