Search

Combining photothermal therapy (PTT) with chemodynamic therapy (CDT) is an efficacious strategy for cancer treatment. However, the hyperthermia-induced heat shock response and low Fenton reaction efficiency limited its clinical application. Here, we present self-assembled querce-tin-Fe3+nanoparticles (Qu-Fe NPs) for synergetic near-infrared (NIR) light-triggered low-temperature PTT (LTPTT) and glutathione (GSH)-activated CDT. Qu-Fe NPs had a broad absorption range extending to the NIR region and excellent photothermal conversion ability. After endocytosis into cancer cells, these NPs partially released Qu that downregulated the expression of heat shock protein 70, in turn allowing for LTPTT. Moreover, Qu-Fe NPs could deplete the overexpressed GSH in cancer cells, increasing their sensitivity to reactive oxygen species. Meanwhile, Fe3+could be reduced to Fe2+, which can react with endogenous H2O2to generate hydroxyl radicals to achieve CDT. Heat generated by PTT could further accelerate the Fenton reaction in CDT, thus resulting in the synergistic effects between LTPTT and CDT. Both in vitroand in vivoresults showed that Qu-Fe NPs could effectively inhibit tumor growth. This work presents a new approach for achieving mutually reinforced, synergetic NPs that can be used for LTPTT/CDT combination therapy.

Clinical phototheranostic agents suffer from low absorption in near-infrared (NIR) region, decreasing singlet oxygen quantum yield (1O2QY) caused by aggregation in water, and low photothermal conversion efficiency (PCE), all of which are factors weakening their phototheranostic efficacy. Herein, we designed and synthesized a donor-acceptor-donor (D-A-D) structured boron-dipyrromethene derivative (B-2TPA) which exhibited NIR absorption and fluorescence. After being encapsulated in amphiphilic distearoyl phosphoethanolamine polyethyleneglycol 2000 (DSPE-PEG-2000), the water-soluble B-2TPAnanoparticles (NPs) had increasing 1O2QY (6.7%) due to the intermolecular aggregation-induced decrease in the energy gap between singlet and triplet excited states. Moreover, the quenched fluorescence and stable twisted intramolecular charge transfer in aggregates further increased the PCE of B-2TPANPs to 60.1%. In vitroand in vivostudies confirmed that B-2TPANPs could be used in NIR fluorescence and photoacoustic imaging-guided synergistic photodynamic and photothermal therapy in tumor treatment.

Combining phototherapy and chemotherapy has been considered a promising modality for cancer therapy due to their synergistic effect. Herein, we developed three D-π-A-structured boron dipyrromethenes (BODIPYs) (named as B-B, B-C, and B-C-Pt). Due to their enlarged π-conjugated structure and high intramolecular charge transfer effect, the synthesized BODIPYs had photothermal conversion capability, and their absorption and fluorescence spectra were red-shifted. The cisplatin-appended BODIPY (B-C-Pt) exhibited good singlet oxygen (1O2) generation ability and near infrared (NIR) absorption and fluorescence (λAbs= 748 nm, λEm= 947 nm). After being encapsulated by distearoyl phosphoethanolamine polyethyleneglycol 2000 (DSPE-PEG-2000), which could inhibit the H-aggregation of B-C-Pt, the absorption and fluorescence of the obtained B-C-Ptnanoparticles (NPs) were red-shifted to 762 and 985 nm, respectively. The 1O2quantum yield and photothermal conversion efficiency of the B-C-PtNPs were 4.0% and 40.6%, respectively. Moreover, B-C-PtNPs had chemotherapeutic efficacy due to the presence of cisplatin. In vitroand in vivostudies further demonstrated that B-C-PtNPs had synergistic therapeutic efficacy. Together, B-C-PtNPs could be employed in NIR II fluorescent and photoacoustic imaging-guided synergistic phototherapy and chemotherapy for cancer treatment.

Benzoyl peroxide (BPO) has been added in wheat flour because of its bleaching effect. However, the abnormal used BPO has caused increasing concern due to its strong oxidization capability which may have adverse effects on living organisms. Herein, we present a carbon dot (CD)-based fluorescent and colorimetric probe for visually, sensitively and selectively sensing BPO. The addition of BPO could quench the red fluorescence of CDs peaked at 622 and 677 nm, and decrease the absorbance at 613 nm, while increase the absorbance at 450 nm, resulting in a fluorescence turn-off and colorimetric spectral response. Moreover, the CDs had short response time of 10 min and high sensitivity towards BPO with a low limit of detection of 28 nmol/L. The applicability of the CDs in detecting BPO in wheat, noodle and starch samples was further demonstrated, and good recovery results were obtained.

Ordered mesoporous siliceous material has been identified as one of the key elements of the catalysis concept. Here we report an efficient Friedel-Crafts reaction of indoles with isatins catalyzed by PWA/MCM-41, which got the di(indolyl)indolin-2-ones derivatives with high yield. Moreover, the catalysts were characterized by XRD and SEM/EDS, the EDS spectrum indicated that the catalyst used in this reaction also contains tungsten, and the proposed mechanism for the synthesis of 3,3-di(indolyl)indolin-2-ones was also discussed. Finally, the catalyst can be reused repeatedly for several times without obvious loss of activity.