Anionic Quantum Dots reveal actin-microridges in zebrafish epidermis

Enhancement of hydrophilicity and functionalization of CdTe QDs (Quantum Dots) via surface modifications have made them suitable to be used as specific probes for cell imaging. Applications for targeting cell surfaces have been widely demonstrated in vitro but their use in animal models is not trivial. Here, we reported the interaction of mercaptosuccinic-coated (MSA) CdTe QDs with the epidermis of living and Carnoy-fixed zebrafish embryos. QDs concentrate along adherent junctions and reveal the characteristic pattern of actin microridges at the apical surface of the enveloping layer. In our study, labeling with anionic QDs is attained within few minutes at submicromolar concentrations in whole mounted Carnoy-fixed zebrafish embryos, providing a faster approach compared with immunodetection or standard Phalloidin staining of actin for visualization by fluorescence microscopy.