Photoactivated chemotherapy (PACT) is a novel cancer treatment method that has drawn increasing attention due to its high selectivity and low side effects by spatio-temporal control of irradiation. Compared with photodynamic therapy (PDT), oxygen-independent PACT is more suitable for treating hypoxic tumors. By finely tuning ligand structures and coordination configurations, many Ru(II) complexes can undergo photoinduced ligand dissociation, and the resulting Ru(II) aqua species and/or free ligands may have anticancer activity, showing their potential as PACT agents. In this mini-review, we summarized the progress in Ru(II)-based PACT agents, as well as challenges that researchers in this field still face.

Uniformly dispersed ultrafine platinum nanoparticles confined in a covalent organic framework (Pt/COF) have been designed and synthesized, which exhibit good catalytic activities in both enzyme-like and electrocatalytic catalysis. Benefiting from the space-confinement effect of pores in the COF matrix, the size of in situ grown Pt nanoparticles is as small as 2.44 nm with a narrow size distribution. Owing to the structure superiority, the Pt/COF catalyst exhibits much better peroxidase/oxidase-like activity than unsupported Pt nanoparticles and a physical mixture of the two components. Based on the inhibition of catalytic oxidation of the peroxidase substrate by Pt/COF, a sensitive colorimetric method is established for tannic acid sensing. Furthermore, the Pt/COF catalyst also exhibits better electrocatalytic activity and stability than commercial Pt/C catalyst towards the methanol oxidation reaction (MOR). This work demonstrates the promising application potential of COF-supported materials in both enzyme-mimetic and electrocatalytic catalysis.

Regulating the catalytic activity of nanozymes is significant for their applications in various fields. Here, we demonstrate a new strategy to achieve reversible regulation of the nanozyme's activity for sensing purpose. This strategy involves the use of zero-dimensional MoS₂ quantum dots (MQDs) as the building blocks of nanozymes which display very weak peroxidase (POD)-like activity. Interestingly, such POD-like activity of the MQDs largely enhances in the presence of Fe³⁺ while diminishes with the addition of captopril thereafter. Further investigations identify the mechanism of Fe³⁺-mediated aggregation-induced enhancement of the POD-like activity and the inhibitory effect of captopril on the enhancement, which is highly dependent on their concentrations. Based on this finding, a colorimetric method for the detection of captopril is developed. This sensing approach exhibits the merits of simplicity, rapidness, reliability, and low cost, which has been successfully applied in quality control of captopril in pharmaceutical products. Moreover, the present sensing platform allows smartphone read-out, which has promising applications in point-of-care testing devices for clinical diagnosis and drug analysis.