[20a-P7-1~37] 12.1 Fabrications and Structure Controls

[20a-P7-28] Correlation between molecular distortion and color in carotenoids crystals

〇Ryuju Suzuki¹, Okada Satoshi¹, Deguchi Shigeru¹ (1.JAMSTEC)

Keywords:carotenoids, nanocrystals

Carotenoids are natural pigments that are wide-spread in nature with yellow to red color tones. Carotenoids are often nanocrystallized in practical use in the foodstuffs and pharmaceutical industry, because of their insolubility in water. However, the correlation between the morphology and color of the carotenoids nanoparticles has not been entirely clear. In this research, we fabricated nanoparticles of carotenoids and studied their structures and optical properties. Carotenoids (β-carotene, lycopene, lutein, astaxanthin) were successfully nanocrystallized by reprecipitation method. Each of carotenoids formed nanoparticles about 50 nm in size. The powder XRD pattern of the β-carotene nanoparticles was different from that of its single crystal. In addition, absorption spectra of the β-carotene nanoparticles were blue-shifted compared to those of the bulk crystal. The blue shift may suggest that the carotenoids molecules would be conformationally distorted in the nanoparticles.