Lanthanide-doped nanomaterials for luminescence detection and imaging

•Lanthanide-doped nanomaterials are essential for optical imaging.•Lanthanide-doped nanomaterials have excellent luminescence.•Lanthanide-doped nanomaterials can be functionalized with polymers.•Lanthanide-doped luminescent nanocomposites can be used in analytical chemistry.•Regulated and multicolor emissions of lanthanide-doped nanocomposites can be useful.

Lanthanide-doped inorganic nanomaterials are a prominent class of nanocrystals with multicolor emissions that are an essential tool for optical imaging in analytical chemistry. Based on the excellent luminescence of lanthanide-doped nanomaterials, novel nanocomposites with diverse sizes (sub-10 nm) and properties, such as luminescence-plasmon, magnetism-luminescence, and upconversion (UC) and downconversion (DC) dual-mode luminescence, have been designed and prepared. These functional nanocomposites have been achieved by functionalization of lanthanide-doped nanomaterials with various types of polymers, responsive moieties, and targeting molecules. Here, we summarize the recent advancements in application of lanthanide-doped luminescence nanocomposites in analytical chemistry and highlight the challenges for future research. Precisely regulated and multicolor-emission lanthanide-doped nanocomposites will be a next thrust for applications in theranostics. Future applications of lanthanide-doped nanocomposites will benefit from such research.