title: Caffeine-loaded niosomes: characterization and in vitro release studies.
abstract: We prepared different neutral and positively charged niosomal formulations containing sorbitan esters for entrapment of caffeine. Drug entrapment reduced following the incorporation of positively charged molecule. Furthermore, the span 60-containing niosomes showed the highest drug encapsulation efficiency due to solid-state nature of this surfactant's bilayers. There was a regular relationship between lipophilicity (HLB values) of surfactants and mean particle sizes; increasing the HLB value resulted in larger niosomes. By means of diffusion experiments with Franz diffusion cells, the effects of different vesicular components and that of the positive charge on the release of caffeine from various vesicle formulations were studied. Obtained results indicate that a combined erosion-diffusion mechanism regulates the permeation of caffeine through cellulose acetate membranes. High encapsulation efficiency, appropriate size distribution, and good vesicular stability, especially in solid state niosomes, make this type of vesicular systems a good alternative to liposomes for topical delivery of caffeine.
authors.affiliation: Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, and Pharmaceutical Technology Research Center, Kerman University of Medical Sciences, Kerman, Iran.
authors.forename: Payam
authors.initials: P
authors.lastname: Khazaeli
authors.forename: Abbas
authors.initials: A
authors.lastname: Pardakhty
authors.forename: Hamideh
authors.initials: H
authors.lastname: Shoorabi
mesh_terms: D000287:Administration, Topical; D002110:Caffeine / Q000737:chemistry*; D002482:Cellulose / Q000031:analogs & derivatives; D000697:Central Nervous System Stimulants / Q000737:chemistry*; D002626:Chemistry, Pharmaceutical; D004058:Diffusion; D004337:Drug Carriers / Q000737:chemistry*; D004355:Drug Stability; D004356:Drug Storage; D006601:Hexoses / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D008081:Liposomes; D008567:Membranes, Artificial; D010316:Particle Size; D011136:Polysorbates / Q000737:chemistry; D013501:Surface-Active Agents / Q000737:chemistry; D013696:Temperature
chemical_list: D000697:Central Nervous System Stimulants; D004337:Drug Carriers; D006601:Hexoses; D008081:Liposomes; D008567:Membranes, Artificial; D011136:Polysorbates; D013501:Surface-Active Agents; D002110:Caffeine; C005062:acetylcellulose; D002482:Cellulose; C009298:sorbitan monostearate