A Highly Photostable Near‐Infrared Labeling Agent Based on a Phospha‐rhodamine for Long‐Term and Deep Imaging

• DOI: 10.1002/anie.201804731
• Publication Date: 2018-07-09T01:49:20Z
• Authors: Marek Grzybowski; Masayasu Taki; Kieko Senda; Yoshikatsu Sato; Tetsuro Ariyoshi; Yasushi Okada; Ryosuke Kawakami; Takeshi Imamura; Shigehiro Yamaguchi
• Keywords: Rhodamine; Rhodamine B; Fluorescence-lifetime imaging microscopy; Biomolecule

Various fluorescence microscopy techniques require bright NIR-emitting fluorophores with high chemical and photostability. Now, the significant performance improvement of phosphorus-substituted rhodamine dyes (PORs) upon substitution at 9-position a 2,6-dimethoxyphenyl group is reported. The thus obtained dye PREX 710 was used to stain mitochondria in living cells, which allowed long-term three-color imaging vis-NIR range. Moreover, longevity allows tracking dye-labeled biomolecule by single-molecule under physiological conditions. Deep blood vessels mice brain has also been achieved using 710-dextran conjugate.