Highly sensitive light-up near-infrared fluorescent probe for detection and imaging of β-glucuronidase in human serum,living cells and tumor-bearing mice

β-Glucuronidase(GUS)plays a key role in tumor initiation,metastasis,and progression,and thus,has been proposed as a promising cancer biomarker.In this study,we designed an enzyme-activatable near-infrared(NIR)fluorescent probe(DCM-βGlcA)for the rapid and accurate detection of GUS activity in vitro,in vivo and ex vivo.The DCM-βGlcA was prepared by linking a glucuronic acid residue to dicyanomethylene-4 H-pyran(DCM).This probe exhibited significant light-up NIR fluorescent signals at 680 nm after reacting with GUS and the Stokes shift could reach 150 nm.The DCM-βGlcA showed a high sensitivity toward GUS and an excellent linear relationship at concentrations ranging between 0 and 4 U L^(-1)(R^(2)=0.9974)with the limit of detection as low as 0.19 U L^(-1).We used the DCM-βGlcA to identify GUS serum levels in both cancer patients and healthy individuals with a similar accuracy as that of an enzyme-linked immunosorbent assay(ELISA)while being easier and faster to perform.Moreover,the DCM-βGlcA was used for tracking endogenous GUS in living cells,thereby discriminating GUSoverexpressed liver cancer from normal cells.Additionally,the DCM-βGlcA was able to detect and image endogenous GUS in liver cancer tissue and tumor-bearing mouse models.These findings demonstrate the potential of the DCM-βGlcA as a promising tool for detecting and monitoring GUS activity in preclinical applications.

Preparation of ultrathin ReS2 nanosheets and their application to Q-switched Er-doped fiber lasers

We study the exfoliation of ultrathin ReS2 nanosheets from the prepared ReS2 powder and their application to Q-switched Er-doped fiber laser.XRD,Raman,and XPS spectra confirm the successful preparation of the layered ReS2.SEM images show that the obtained ReS2 sheets have lateral size below 200 nm.The thickness of the ReS2 nanosheets is smaller than 5 nm according to the AFM results.ReS2/PVA film is applied as a saturable absorber in an Er-doped Q-switched fiber laser,and a minimum pulse duration of 2.4μs and an output power of 1.25 mW are obtained,indicating the potential application to Q-switched lasers.

Ultralong-life lithium metal batteries enabled by decorating robust hybrid interphases on 3D layered framworks

Stable solid-electrolyte interphase(SEI)is crucial for advanced development of lithium metal batteries.However,the continuous collapse and reconstruction of SEI will deplete fresh Li and electrolytes upon cycling,leading to irreversible capacity loss.Herein,we addressed this issue by pre-formation of artificial robust hybrid interphase on a 3D layered graphene/lithium metal framework,in which is constructed by LiF associated with Li2TiF 6generated by the in-situ reaction between the surfacial lithium and titanium fluoride contained electrolytes.The as-obtained interphase can maintain the structure integrality and avoid continuous consumption of the fresh Li and electrolytes.As a consequence,the Li symmetric cells achieve high-efficiency Li deposition and stable cycling over 3600 h.When paired with LiFePO_(4)cathodes,the coin cells exhibit long lifespan(>800 cycles)with almost 88.3%retention of the initial capacity.