Deep-Red and Near-Infrared Xanthene Dyes for Rapid Live Cell Imaging

Abstract

In this work, two xanthene dyes (H-hNR and TF-hNR) have been synthesized by a convenient and efficient method. These two dyes exhibited deep-red and near-infrared emissions, high fluorescence quantum yields, and good photostability. Their structure-optical properties were investigated by X-ray crystal structure analysis and density functional theory calculations. Live cell imaging data revealed that H-hNR and TF-hNR could rapidly stain both A549 and HeLa cells with low concentrations. The excellent photophysical and imaging properties render them as promising candidates for use in live cell imaging.

PONy Dyes: Direct Addition of P(III) Nucleophiles to Organic Fluorophores

“…7-(dimethoxyphosphoryl)-3,10-bis(dimethylamino)- 5,6-dihydrobenzo[c]xanthen-12-ium trifluoroacetate Trimethyl phosphite (Sigma-Aldrich; 88 µL, 0.75 mmol, 3 eq) was added at room temperature to a screw-cap test tube containing a stirred solution of H-hNR dye [6] (perchlorate salt; 112 mg, 0.25 mmol) and tetrabutylammonium iodide (92 mg, 0.25 mmol, 1 eq) in dry CH2Cl2 (6 mL). The reaction mixture was evaporated on Celite and the leuco dye was isolated by flash chromatography on Biotage Isolera system (Sepacore Silica HP cartridge, 12 g SiO2; gradient 50% to 100% EtOAchexane over 10 column volumes).…”

“…HPLC: tR = 11.4 min (peak area 98%), MeCN/H2O + 0.1% TFA in both components: 20/80 -100% MeCN in 20 min, detection at 570 nm and 600 nm, column 4×250 mm, flow rate 1.2 mL/min. NMR (400 MHz, CD3CN) δ 8.86 (d, J = 9.9 Hz, 2H), 7.18 (dd, J = 9.9 and 2.6 Hz, 2H),6.79 (« t », J = 2.4 Hz, 2H), 4.86 (dp, J = 7.6 and 6.1 Hz, 2H, CHO), 3.32 (s, 12H, NMe2), 1.45 (d, J = 6.1 Hz, 6H, diastereotopic methyl groups in iPr),1.19 (d, J = 6.1 Hz, 6H, diastereotopic methyl groups in iPr).…”

Rationally Designed Furocarbazoles as Multifunctional Aggregation Induced Emissive Luminogens for the Sensing of Trinitrophenol (TNP) and Cell Imaging

“…Above all, the widespread use of explosive formulations poses a serious threat to the human condition, including skin irritation, anemia, and carcinogenicity, among several others . Therefore, the analysis of explosives has been of importance and several attempts have been committed to designing new materials for detecting nitroaromatics (NACs) . The high risk associated with TNT urged us to use trinitrophenol (TNP) as an analyte, which interestingly has superior explosive power when compared to TNT as well as higher water solubility which also threatens the aquatic life and biodiversity.…”

Synthesis, stability and spectral behavior of fluorogenic sulfone-pyronin and sulfone-rosamine dyes

“…To achieve sensitive and reliable fluorescence detection in complex biological systems or in living organisms, and thus considering biomedical applications for xanthene-based fluorophores, current research efforts are primarily devoted to the design of rhodamines and related compounds having absorption/emission maxima in the spectral range 650-900 nm [15], often called "therapeutic optical window" (or NIR-1 window) [16]. The relevant strategies implemented to achieve this goal can be classified into two main categories: (1) the extension of the p-conjugated system either through the introduction of various fused aromatic rings within the xanthene core [17][18][19][20][21][22][23][24][25][26][27][28][29][30] or the installation of a dimethine bridge connecting another chromophore unit (e.g., dihydroxanthene-hemicyanine fused dyes) [31,32], and (2) the replacement of the 10-position O atom of xanthene by a group 14 element (i.e., C, Si, or Ge) [33][34][35][36] or an oxidized-heteroatom such as B(OH) 2 [37], P(O)R [38,39], P(O)OR [40], or Te(O) [41]. This latter approach is particularly attractive because it produces dyes with significantly red-shifted absorption and fluorescence maxima, typically around or above 650 nm, and keeping compact structures and small molecular weights.…”