Activatable Near-Infrared Fluorescent and Photoacoustic Dual-Modal Probe for Highly Sensitive Imaging of Sulfatase In Vivo

Abstract

Sulfatase is an important biomarker closely associated with various diseases. However, the state-of-the-art sulfatase probes are plagued with a short absorption/emission wavelength and limited sensitivity. Developing highly sensitive fluorescent probes for in vivo imaging of sulfatase remains a grand challenge. Herein, for the first time, an activatable near-infrared fluorescence/photoacoustic (NIRF/PA) dual-modal probe (Hcy-SA) for visualizing sulfatase activity in living cells and animals is developed. Hcy-SA is composed of a sulfate ester moiety as the recognition unit and a NIR fluorophore hemicyanine (Hcy-OH) as the NIRF/PA reporter. The designed probe exhibits a rapid response, excellent sensitivity, and high specificity for sulfatase detection in vitro. More importantly, cells and in vivo experiments confirm that Hcy-SA can be successfully applied for PA/NIRF dual-modal imaging of sulfatase activity in living sulfatase-overexpressed tumor cells and tumor-bearing animals. This probe can serve as a promising tool for sulfatase-related pathological research and cancer diagnosis.

A near-infrared fluorescent probe for detecting hydrogen sulfide with high selectivity in cells and ulcerative colitis in mice

“…Against this background, small molecule fluorescent probes have attracted extensive attention in the field of biosensing due to their outstanding merits such as real-time detection, high temporal and spatial resolution, in situ non-invasiveness and good biocompatibility. 16–26 As yet, a series of H 2 S-responsive fluorescent probes have been designed and synthesized, but it is difficult to use many of them in vivo as a result of the disadvantages of short emission wavelength and small Stokes shift (Table S1†). For instance, the Huo group reported a nitro-reduction strategy-based H 2 S fluorescent probe, manifesting the eminent imaging ability for H 2 S in living cells.…”

A large Stokes shift NIR fluorescent probe for visual monitoring of mitochondrial peroxynitrite during inflammation and ferroptosis and in an Alzheimer's disease model

“…When compared with conventional ONOO − detection techniques, such as electrochemistry, 16 electron paramagnetic resonance spectroscopy, 17 ultraviolet–visible (UV–vis) absorption spectroscopy, 18 and high-performance liquid chromatography, 19 fluorescence imaging is a practical and reliable method for tracking various biomolecules and biological parameters in living systems owing to its simplicity, high sensitivity, biocompatibility, non-invasiveness, and real-time detection capabilities. 20–22 Thus far, several fluorescent probes have been reported for detecting ONOO − in biological systems (Table S1†). For example, Zhao et al constructed an ONOO − -responsive green fluorescent probe using boron dipyrromethene (BODIPY) and 4-hydroxyaniline as the core and recognition sites, respectively.…”

Engineering a near-infrared LAP fluorescent probe with high sensitivity and selectivity for surgical resection of liver cancer

“…Fluorescent probes, especially near-infrared fluorescent probes, have attracted much more attention due to the advantages of higher spatiotemporal resolution, lower photon scattering of biological tissues, stronger tissue penetration ability, low background fluorescence in biological tissues, and weak spontaneous fluorescence, which allow the capture of deeper and more accurate biological information. 7–19 Recently, the development of fluorescent probes to detect liver tumors has continued to increase in recent years. 20–32 Despite their improvements, as for the sensitivity and specificity of most of these probes, they still have some limitations with regard to their uses.…”