Research conducted by N. Murthy and co-authors at Georgia Tech and the Emery University School of Medicine, both in Atlanta, USA, and the Atlanta VA Medical Center in Decatur, Ga., USA, reports that a family of sensors based on a hydrocyanine scaffold allows imaging of reactive oxygen species (ROS) in vivo. Species such as superoxide and the hydroxyl radical have significant roles in inflammatory diseases, thus these biological probes could prove beneficial to medical diagnostics and other research.
According to a report by the American Chemical Society, the hydrocyanine skeleton forms when the iminium cation of a cyanine dye is reduced with NaBH4. Hydrocyanines typically are weakly fluorescent because the reduction disrupts their structures; however, fluorescence is increased, reportedly up to 118-fold, by oxidation with ROS via regeneration of the extended conjugated structure. Researchers prepared five test hydrocyanine compounds, at least two of which exhibit wavelengths in the near-IR, making it possible to detect ROS in vivo.
ROS detection in vivo was confirmed with fluorescence measurements by using one compound in the presence of lipopolysaccharide-treated mouse tissue. Whereas initial work suggests the hydrocyanines could be useful research tools for medical diagnostics, the personal care arena might find this technology applicable to the study of aging mechanisms in skin.