A multi-glycomic platform for the analysis of food carbohydrates.

Carbohydrates comprise the largest fraction of most diets and exert a profound impact on health. Components such as simple sugars and starch supply energy, while indigestible components, deemed dietary fiber, reach the colon to provide food for the tens of trillions of microbes that make up the gut microbiota. The interactions between dietary carbohydrates, our gastrointestinal tracts, the gut microbiome and host health are dictated by their structures.

Bottom-Up Then Top-Down Synthesis of Gold Nanostructures Using Mesoporous Silica-Coated Gold Nanorods.

Gold nanostructures were synthesized by etching away gold from heat-treated mesoporous silica-coated gold nanorods (AuNR@mSiO), providing an example of top-down modification of nanostructures made using bottom-up methodology. Twelve different types of nanostructures were made using this ottom-p-hen-p-dowynthesis (BUTTONS), of which the etching of the same starting nanomaterial of AuNR@mSiO was found to be controlled by how AuNR@mSiO were heat treated, the etchant concentration, and etching time. When the heat treatment occurred in smooth moving solutions in round-bottomed flasks, red-shifted longitudinal surface plasmon resonance (LSPR) was observed, on the order of 10-30 min, indicating increased aspect ratios of the gold nanostructures inside the mesoporous silica shells.