الفهرس 
AbstractOnly 14 pages are availabe for public view
 |  | from | 500 |  |  |
| | | from | 500 | | |
Abstract
Drug targeting in treatment of asthma includes either direct application of a drug into bronchi in higher concentration than that in other organs. The successful example of this approach includes administration of antiasthmatic agents loaded in metered dose inhalers (MDIs) inhalers directly to the lung, or through indirect delivery as in rectal administration. Moreover, transdermal administration as skin hydrogel may act also as targeting drug; since loss in drug is minimal. For protecting antiasthmatic agents from chemical degradation; provide sustained release to improve the availability of the drug; and provide a targeting effect to improve the efficiency of the drug; they are encapsulated into non-toxic vesicles which can encapsulate both hydrophilic and hydrophobic materials referred as niosomes and liposomes. The main objectives in this investigation were; to prepare niosomes composed of span60 and cholesterol in different molar ratios containing ketotifen fumarate and salbutamol sulphate as prophylactic and treatment of asthma.. The physical properties and in-vitro release characteristics of these tablets were evaluated using scanning and transmission electron microscope in addition to XRD and DSC to examine the EE%, formation of niosomes, their sizes, the calorimetric behavior and the crystalline nature of the drug befor and after the preparation of niosomes. Furthermore, MDIs containing the selected niosomes were also prepared and evaluated for their physical properties. In addition, liquid suppositories of P407 and P188, PEG, WH15 with Tween and propylene glycol, HPMC, carbopol 934 with and without liposomes and niosomes containing drugs were also prepared and evaluated. The bioavailability of ketotifen fumarate from selected formulae I human volunteers and the stability of salbutamol sulphate were also studied. The obtained results revealed that, the in-vitro release profiles from the different prepared formulae were dependant on span 60 : cholesterol molar ratios, P407: P188 ratios, the type of solid suppositories bases, and the viscosity of HPMC, carbopol 934 with and without liposomes and niosomes. Also, niosomal salbutamol sulphate in all ratios have high stability upon storage for three months at 2-8 ˚C. niosomes also for the two drugs showed controlled release effect. Also, niosomal ketotifen fumarate in MDIs showed higher bioavailability in comparison to that containing the drug alone indicated by higher Cmax attained in longer Tmax and higher AUC0-24 values in human volunteers. Also, the obtained results revealed that, the in-vitro release profiles of the two drugs from HPMCgels were higher than that of carbopol 934. Also, it was found that, niosomal and liposomal hydrogels showed controlled release of the drugs in comparison to HPMC and carbopol934 gels. Furthermore, liquid suppositories composed of mixture of P407/P188 in concentration of 21/9 achieved the most optimal gel temperature, gel strength, bioadhesive force. Also, 21/9 liquid suppositories have the highest drugs release compared to PEG, WH15 with Tween and propylene glycol conventional suppositories.