Investigation of photosensitively bioconjugated targeted quantum dots for the labeling of Cu/Zn superoxide dismutase in fixed cells and tissue sections.

This study presents the development of targeted and antibody cross-linked QDs and explores whether these bioconjugates could specifically and effectively label Cu/Zn superoxide dismutase (SOD1) on fixed cells and tissues. QD-antibody conjugation was achieved by using our previously invented AmiNoacid (monomer) Decorated and Light Underpining Conjugation Approach (ANADOLUCA) method. In this method, we have used a photosensitive aminoacid monomer having ruthenium complex which is a synthetic and inexpensive material for the preparation of bioconjugates. Its specificity was demonstrated by extracting the active enzyme from rat liver lysate by using the bioconjugate. It provided accurate antibody orientation, high specificity and mechanic stability. The protocol steps for QD-antibody conjugation and specimen preparation were described in detail. The nanobioconjugates were prepared under mild conditions (for example in day light), independent of pH and temperature, without affecting conformation and function of protein. This protocol is simple, inexpensive and can be successfully adapted to detect other targets on different cell types and tissues.