Anantachoke Natthinee, Makha Mohamed, Raston Colin L, Reutrakul Vichai, Smith Nigel C, Saunders Martin
Department of Chemistry, Faculty of Science, Mahidol University, Bangkok 10400, Thailand.
J Am Chem Soc. 2006 Oct 25;128(42):13847-53. doi: 10.1021/ja063545n.
Nanoparticles of trans-beta-carotene are accessible using spinning disk processing (SDP), by varying the reaction conditions and the choice of surfactant, macrocyclic amphiphiles, sulfonato-calix[4,5,6,8]arenes, and alpha,beta-cyclodextrins. SDP ensures rapid mixing and fast kinetics, and nanoparticles of the carotene formed in the presence of the calixarenes are stable with respect to extraction of the carotene into an organic solvent, unlike in the presence of the cyclodextrins. Insight into the supramolecular structure of the carotene nanoparticles has also been established. The mean particle sizes (dynamic light scattering, DLS) have been optimized at 40(2) and 56(1) nm and 71.4(6) and 82(1) nm, respectively, for each sulfonato-calix[5,6 and 4,8]arene, whereas the cyclodextrins form nanoparticles with a mean diameter of 71(1) and 68.5(6) nm, respectively. Zeta-potential studies show stability of all the colloidal dispersions at pH > 4 with values below -30 mV. UV-visible spectroscopy shows a blue shift indicative of H-aggregates of the carotene within the nanoparticles. The surface area derived from BET studies is 39.12 m(2)/g corresponding to particles of 76.7(5) nm in diameter, in agreement with sizes obtained from DLS and TEM measurements.
通过旋转盘处理（SDP），改变反应条件以及表面活性剂、大环两亲物、磺基杯[4,5,6,8]芳烃和α,β-环糊精的选择，可以制备反式β-胡萝卜素纳米颗粒。SDP可确保快速混合和快速动力学，与环糊精存在时的情况不同，在杯芳烃存在下形成的胡萝卜素纳米颗粒在将胡萝卜素萃取到有机溶剂中时是稳定的。对胡萝卜素纳米颗粒的超分子结构也有了深入了解。对于每种磺基杯[5,6和4,8]芳烃，平均粒径（动态光散射，DLS）分别优化为40(2)和56(1) nm以及71.4(6)和82(1) nm，而环糊精形成的纳米颗粒平均直径分别为71(1)和68.5(6) nm。ζ电位研究表明，在pH > 4时，所有胶体分散体均稳定，其值低于 -30 mV。紫外可见光谱显示出蓝移，表明纳米颗粒内胡萝卜素形成了H-聚集体。BET研究得出的表面积为39.12 m²/g，对应于直径为76.7(5) nm的颗粒，这与从DLS和TEM测量获得的尺寸一致。
