Amornset TachaprutinunThanchanok UdomsupChuleeporn LuadthongSupason WanichwecharungruangMahidol UniversityChulalongkorn University2018-09-132018-09-132009-06-05International Journal of Pharmaceutics. Vol.374, No.1-2 (2009), 119-124037851732-s2.0-67349177762https://repository.li.mahidol.ac.th/handle/20.500.14594/28319The encapsulation of astaxanthin into polymeric nanospheres by solvent displacement was compared for three chemically diverse polymers, namely; poly(ethylene oxide)-4-methoxycinnamoylphthaloylchitosan (PCPLC), poly(vinylalcohol-co-vinyl-4-methoxycinnamate) (PB4) and ethylcellulose (EC). Although capable of forming nanospheres themselves, EC could not encapsulate astaxanthin at all, whilst PB4 yielded a poor encapsulation efficiency. In contrast, PCPLC yielded reasonably good encapsulation efficiency (98%) at a loading of 40% (w/w). Moreover, the freeze-dried astaxanthin-encapsulated PCPLC nanospheres showed good dispersibility in water yielding stable aqueous suspensions of 300-320 nm nanoparticles. A steady release of astaxanthin from the nanospheres up to a maximum of ∼85% payload over 60 min was also demonstrated, at least in acetone. NMR analysis indicated that after a two-hour-heating at 70 °C in an aqueous environment, PCPLC nanoencapsulated astaxanthin showed minimal heat degradation of olefinic functionality in contrast to that of the unencapsulated pigment molecules which were almost completely destroyed. © 2009 Elsevier B.V. All rights reserved.Mahidol UniversityPharmacology, Toxicology and PharmaceuticsArticleSCOPUS10.1016/j.ijpharm.2009.03.001