Colloidal photonic crystal stationary phases - films, monoliths, columns.

摘要

Chromatography, the separation of complex molecule mixtures, is a very powerful analytical technique. Since its invention a century ago it has been continuously adapted and developed. Particulate beds are at the verge of being exchanged for continuous monolithic beds, columns lengths are shrinking towards the centimeter range. Research is driven by a demand for ever more efficient chromatography and integrated separation and analysis systems on chips.;The ideal particulate chromatographic stationary phase and the colloidal crystal structure share a related and comparable building plan. It is an appealing concept to merge aspects of these two fields. A synthesis of stationary phase and optically responsive crystal could lead to an actively sensing chromatographic bed.;Here we produce colloidal photonic crystal films, monoliths, columns and their inverse constructs. The structures are examined for their structural and optical properties, as well as their suitability for optically responsive separation phases. An image processing method measuring refractive indices and refractive index changes is developed, which is based on the optical response of colloidal photonic crystal films and capillaries. Capillary colloidal crystals are brought to an applicable stage and are integrated into a nanovolume liquid chromatography system as microbore capillary columns.;In twenty years the concept of light localization in three-dimensional periodic structures has created the constantly expanding field of photonic crystals. A facile bottom-up approach to photonic structures is the self-assembly of monodisperse colloidal microspheres. Emerging applications are non-linear optical devices, structural colors, and refractive index change sensitive sensors. There exists a continuous search for additional and alternative uses to benefit and apply gained knowledge from the colloidal photonic crystal research.