Abstract: Applications in nanomedicine, such as diagnostics and targeted therapeutics, rely on the detection and targeting of membrane biomarkers. The present invention, in one embodiment, utilizes quantitative profiling, spatial mapping, and multiplexing of cancer biomarkers using functionalized quantum dots. This approach provides highly selective targeting molecular markers for pancreatic cancer with extremely low levels of non-specific binding and provides quantitative spatial information of biomarker distribution on a single cell, which is important since tumors cell populations are inherently heterogeneous. The quantitative measurements (number of molecules per square micron) is validated using flow cytometry and demonstrated using multiplexed quantitative profiling using color-coded quantum dots.