A dual-site fluorescent probe for discriminately detecting low and high concentration of hypochlorite in living cells

Novel fluorescence probe for ClO- in living cells: Based on FRET mechanism

Hypochlorous acid (HClO) as a kind of reactive oxygen species (ROS) plays a vital role in many biological processes. Organic fluorescence probes have attracted great interests for the detection of HClO, due to their relatively high selectivity and sensitivity, satisfactory spatiotemporal resolution and good biocompatibility. Constructing fluorescence probes to detect HClO with advantages of large Stokes shift, wide emission gap, near infrared emission and good water solubility is still challenging. In this work, a new ratiometric fluorescence probe (named HCY) for HClO was developed. FRET-based HCY was constructed by bonding a coumarin and a flavone fluorophore. In absence of HClO, HCY exists FRET process, however, FRET is inhibited in the presence of HClO because the conjugated double bond broke. Due to the good match of the emission spectrum of the donor and the absorption spectrum of the acceptor, the FRET system appears favorable energy transfer efficiency. HCY showed high sensitivity and rapid response time. The linearity between the ratios of fluorescence intensity and concentration of HClO was established with a low limit of detection. What's more, HCY was also applied for fluorescence images of HClO in RAW264.7 cells.

Benzylidene-isophorone hybrids with strong anticancer activity

Isophorone is a cyclic ketone that has gained significant attention in the field of organic chemistry due to its versatile reactivity and structural attributes. Derivatives of isophorone offer a broad spectrum of applications ranging from pharmaceuticals to polymer chemistry. With the aim of developing novel hybrid structures based on benzylidene by combining with isophorone scaffold, we report 3 derivatives of the benzylidene-isophorone hybrids and its potent anticancer activity. In order to optimize the anticancer activity of hybrids di-substitution of -Cl group in C2 and C6 position of phenyl ring (compound1), -OCH3 group in C2 and C5 position of phenyl ring (compound2), and -OCH3 group in C2 and C3 position of phenyl ring (compound3) of benzylidene (PhCH=) moiety were made. The structure of Compounds1,2 and 3 were elucidated using spectral and XRD methods. Compounds1,2 and 3 exhibit space group P c a 21, P-1, and P 1 21/n 1 respectively. Compounds1,2 and 3 were tested for the potent anticancer activity on MDA MB-231 cell line. All the three compounds exhibit good anticancer activity on the breast cancer cells. The parent hybrid with ortho, ortho directing -Cl (1) exhibits strong antiproliferation effect (IC50 = 0.028 µM) on MDA-MB 231 cell line. However, hybrid structures with ortho, meta directing -OCH3 (2) group showed moderate effect (IC50 = 0.061 µM) and hybrid with ortho, meta directing -OCH3 (3) substitution showed the least potent anticancer activity (IC50 = 0.074 µM). The benzylidene-isophorone hybrids exhibit anticancer effects in the following order: 1 > 2 > 3.

Novel NIR fluorescent probe for hypochlorite ion detection in biological systems

This study presents the synthesis and application of a novel fluorescent probe, NR-ClO, for the detection of hypochlorite ion (ClO-) in biological systems. The probe was synthesized through a nucleophilic substitution reaction between Nile red and dimethylcarbamothioic chloride. The synthesized probe had high sensitivity and selectivity towards ClO-, with a detection limit of 75 nM and a linear range of 0.1-200 μM. The probe's efficacy was validated through in vitro studies using HepG2 cells and in vivo experiments using a mouse model of rheumatoid arthritis. The findings demonstrate that the NR-ClO probe is a promisingly reliable tool for real-time monitoring of ClO- in complex biological environments.