We developed a new kind of suspension array for multiplexed immunoassays using silica colloidal crystal beads (SCCBs) as coding carriers. The monodisperse and size-controlled SCCBs were fabricated by a microfluidic device. Calcination was employed to improve the mechanical stability and lower the fluorescent background of the SCCBs. Immobilization of protein molecules on the surface of the SCCBs through chemical bonds was studied, and the modification condition was optimized to increase the detection sensitivity. Results indicated that the SCCBs as supports were more sensitive (0.92 ng/mL IgG) than the glass beads (27 ng/mL IgG) and the planar carriers (140 ng/mL IgG). A multiplex immunoassay showed the flexibility and feasibility of SCCBs array in clinical applications.

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Biomimetic enzyme cascade reaction systems in microcapsules are developed for mimicking biocatalysis of organelles.

Photonic crystal (PC) based bioassay techniques have many advantages in sensitive biomolecular screening, label-free detection, real-time monitoring of enzyme activity, cell morphology research, and so on. This study provides an overall survey of the basic concepts and up-to-date research concerning the very promising use of PC materials for bioassays. It includes the design and application of PC fi lms, PC microcarriers, PC fi bers, and PC optofl uidics for fl uorescence enhancement or label-free bioassays. Emphasis is given to the description of the functional structures of different PC materials and their respective sensing mechanisms. Examples of detecting various types of analytes are presented. This article promotes communication among chemistry, biology, medicine, pharmacy, and material science.