A sulfatase-activatable AIEgen nanoprobe for inhalation imaging-guided surgical excision of lung cancer

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

“…Next, we made further efforts to study the reaction kinetics of Hcy-SA with sulfatase. A closer exploration indicated that the enzymatic Michaelis–Menten constants ( K m ) and maximum reaction rate ( V max ) of Hcy-SA toward sulfatase were calculated to be 9.34 μM and 6.02 μM/min, respectively (Figure S14), which were comparable to the literature reported values. − Such a small Michaelis constant suggested the excellent affinity of Hcy-SA with sulfatase. In addition, PA intensities at 700 nm (PA700 intensity) of Hcy-SA treated with different concentrations of sulfatase (0.0–20 U/L) were also recorded to verify the quantitative analysis feasibility of Hcy-SA for sulfatase by PA mode.…”

“…Moreover, the NIRF712 intensity had a good linear relationship with the concentrations of sulfatase in the range of 0.3–12 U/L, and the estimated detection limit is 0.23 U/L (Figure B). It is noteworthy that this sensitivity was superior to that of the existing fluorescent probes, indicating that Hcy-SA provided a highly sensitive means for sulfatase detection. − Molecular docking experiments were carried out to further illustrate the excellent sensitivity of Hcy-SA to sulfatase. As shown in Figure S13, and Tables S2 and S4, Hcy-SA molecules approached the hydrophobic interspace of sulfatase by the hydrophobic interaction with LEU 68, ALA 69, VAL 91, and GLN 153, and the π-cation interactions with LYS 302, indicating the excellent binding ability of Hcy-SA toward sulfatase.…”

“…Fluorescent probes combined with confocal microscopy hold great potential to monitor various enzyme activities with high sensitivity, unrivaled spatiotemporal resolution, and nondestructive fast analysis abilities. , In particular, the activatable fluorescent probes, which can generate enhanced fluorescence signals when interacting with specific molecules or cellular events, realize better response contrast and higher detection sensitivity. , However, the absorption and emission wavelengths of state-of-the-art activatable probes for sulfatase are limited to be within the visible-light region due to utilizing 4-methylumbelliferone, N -methylisoindole, 7-hydroxy-9 H -(1,3-dichloro-9,9-dimethylacridin-2-one), or naphthalimide as the chromophore, hindering further applications in living biological systems. An aggregation induced emission (AIE) fluorescent probe has been constructed for imaging of sulfatase activity in a mouse metastatic lung tumor model, while its fluorescence is far from near-infrared, and the detection limit is unsatisfactory. There is still a lack of reliable and effective methods for the highly sensitive detection of sulfatase activity in living biological systems.…”

“…17,18 However, the absorption and emission wavelengths of state-of-the-art activatable probes for sulfatase are limited to be within the visible-light region due to utilizing 4-methylumbelliferone, 19 N-methylisoindole, 20 7hydroxy-9H-(1,3-dichloro-9,9-dimethylacridin-2-one), 21 or naphthalimide 22 as the chromophore, hindering further applications in living biological systems. An aggregation induced emission (AIE) fluorescent probe has been constructed for imaging of sulfatase activity in a mouse metastatic lung tumor model, 23 while its fluorescence is far from nearinfrared, and the detection limit is unsatisfactory. There is still a lack of reliable and effective methods for the highly sensitive detection of sulfatase activity in living biological systems.…”

Visualizing intracellular dynamics with AIE probes

“…TPE-derivative with a sulfatase recognition unit self-assembled into nanoparticles which could be activated by the catalytic domain of sulfatase to afford hydrophobic DQM-OH, which shows fluorescence on and can further interact with the hydrophobic site of sulfatase to generate stronger fluorescence. 66 As cancer cells are reported to show high sulfatase activity, the probe showed a time-dependent fluorescence enhancement in H460 and A549 cells due to the increased formation of DQM-OH (Fig. 7E).…”