Neocuproine hydrochloride monohydrate is widely used as a chelating agent in biochemical research, particularly for the detection and quantification of copper ions. It forms a stable complex with Cu(I), which is useful in spectrophotometric assays to measure copper concentrations in various samples, such as biological fluids and environmental water.

In analytical chemistry, it serves as a selective reagent for copper analysis due to its high affinity for Cu(I), enabling precise and sensitive detection. It is also employed in studies involving redox reactions, where copper plays a critical role.

Additionally, this compound is utilized in organic synthesis as a catalyst or ligand in reactions involving copper-mediated processes. Its ability to stabilize Cu(I) ions makes it valuable in developing new synthetic methodologies.

In biological research, it is used to investigate copper's role in cellular processes, including enzyme activity and metal homeostasis, providing insights into copper-related diseases and metabolic pathways.