molekulacímkézés

molekulacímkézés is a biophotonic technique used to attach fluorescent, radioactive or other detectable labels to biomolecules such as DNA, RNA, proteins or small molecules, enabling their visualization or quantification in biological systems. The concept originated in the mid‑20th century when chemists began incorporating radiolabels into nucleic acids for tracking cellular processes. With the advent of fluorescence microscopy and high‑throughput sequencing, more sophisticated non‑radioactive labels were developed, including quantum dots, fluorescent dyes and enzyme‑coupled tags.

Common labeling methods include covalent conjugation through amine, thiol or carboxyl groups, enzymatic tagging such as biotin‑avidin coupling, and click chemistry which allows rapid, biocompatible attachment of azide or alkyne functional groups. For nucleic acids, primers or probes can be labeled with fluorophores for polymerase chain reaction or in situ hybridization, while proteins are often tagged with fluorophores or biotin for flow cytometry and surface plasmon resonance.

Applications span basic research and clinical diagnostics. In molecular biology, labeled probes enable the detection of gene expression, chromosomal abnormalities and protein–protein interactions. In drug development, labeling antibodies and small molecules allows pharmacokinetic studies and imaging of therapeutic distribution. Clinical diagnostics use labeled antibodies in immunohistochemistry and flow cytometry to identify cancer biomarkers or infectious agents. Advancements in super‑resolution microscopy have pushed labeling sensitivity and specificity, permitting the observation of sub‑nanometer scale molecular assemblies.

molekulacímkézés remains a critical tool for translational science, bridging the gap between molecular structure and functional phenotype by providing a visible, measurable handle on otherwise invisible biomolecules.