Functional dye molecules, such as porphyrins, attached to CdSe quantum dots (QDs) through anchoring meso-pyridyl substituents, form quasi-stable nanoassemblies. This fact results in photoluminescence (PL) quenching of the QDs both due to Förster resonance energy transfer (FRET) and the formation of non-radiative surface states under conditions of quantum confinement (non-FRET). ...