Abstract: Described herein are photonic crystals comprising a plurality of substantially uniform zein particles. The photonic crystals can be fabricated by assembling the plurality of substantially uniform zein particles into one or more ordered and periodic structures that generate structural color. Also described herein are methods of using the photonic crystals described herein, e.g., as colorants in consumer products, such as food, drugs and/or cosmetics.

Abstract: A dental floss holder for storing and manipulating dental floss used for cleaning a person's teeth comprises a housing, a spool, a fork, a bottom board, a fasten wheel, a block member, a sleeve, a retrieving wheel, a retaining portion and a roll of dental floss which is reeled in the spool, wherein the housing has a position base and an assembling zone at two ends thereof being opposite to each other. The fork is fitted on the position base, the block member is assembled on the housing, the retaining portion is assembled on the bottom board, and the spool, the fasten wheel, the retrieving wheel, the sleeve are defined to coaxially assemble with the assembling zone.

Abstract: A dental floss holder for storing and manipulating dental floss used for cleaning a person's teeth comprises a housing, a spool, a fork, a bottom board, a fasten wheel, a block member, a sleeve, a retrieving wheel, a retaining portion and a roll of dental floss which is reeled in the spool, wherein the housing has a position base and an assembling zone at two ends thereof being opposite to each other. The fork is fitted on the position base, the block member is assembled on the housing, the retaining portion is assembled on the bottom board, and the spool, the fasten wheel, the retrieving wheel, the sleeve are defined to coaxially assemble with the assembling zone.