A system and method of sensing physiological conditions in biological applications includes a laser source for optically exciting a plurality of luminescent quantum dots and a plurality of biomolecules in a nanoscale sensing system having a nanocrystal structure, where the plurality of biomolecules is stained with dye. In a multi-photon excitation process, a laser system optically excites, the plurality of luminescent quantum dots and the plurality of biomolecules in the nanoscale sensing system, where fluorescence resonance energy transfer (FRET) occurs between the plurality of quantum dots and the plurality of biomolecules. Stability of self assembly of quantum dot peptide conjugates within the plurality of biomolecules is investigated. Physiological conditions at the cellular level are determined, using a spectrometer to sense fluorosence spectra. The sensing of physiological conditions includes transducing signals into immunoassays, clinical diagnostics and cellular imaging to provide treatment to biological subjects including human patients.
METHODS OF GENERATING FLORESCENCE RESONANCE ENERGY TRANSFER (FRET) BETWEEN SEMICONDUCTOR QUANTUM DOTS AND FLUORESCENT DYES/PROTEINS VIA MULTI-PHOTON EXCITATION, ACHIEVING ZERO BACKGROUND OR DIRECT EXCITATION CONTRIBUTIONS TO THE FRET SIGNATURE