Unknown, unlabeled test substance molecules (24), are mixed with known concentration of labeled test substance molecules (12).

The emission profile of the fluorophores is used to determine useful information about the labeled and/or non-labeled molecules including molecular interactions between the molecules.

The labeled molecules may be peptides or proteins, although other types of molecules may be labeled.

Eventually, the tagged molecules collide with other tagged molecules, forcing them to link together in pairs.

The labeled molecules may be fragmented, each fragmented molecule creating at least two separate ions.

Labeled molecules may be detected by hybridization or sequencing based methods.

Quantitation of individual molecules may further comprise stochastic labeling of the one or more molecules with a plurality of oligonucleotide tags to produce one or more stochastically labeled molecules.

A novel method for the labeling of oligonucleotides which results in the economical synthesis of 5' labeled molecules.

Subject of the present invention are new isotopic and isobaric tagged molecules, kits comprising them and methods of using them in mass spectrometry.

Also, the invention relates to ligands / nanoparticles / marked molecule compounds and the method of preparing such compounds.

The cell based methods employ capture systems that display collections of tagged molecules specifically linked to capture agents.

The labelled and unlabelled molecules then “compete” for the same antibody binding sites.

The labeled and unlabeled molecules then "compete" for the same antibody binding sites.

The labeled and unlabeled molecules then “compete” for the same antibody binding sites.

The invention also relates to the detecting device which relates to affinity nanocarriers and / or ligands / nanoparticles / marked molecule compounds, especially relates to chips, enzyme marked plates, chromatographic bands.