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Room temperature phosphorescence (RTP) nanoprobes play crucial roles in hypoxia imaging due to their high signal-to-background ratio (SBR) in the time domain. However, synthesizing RTP probes in aqueous media with a small size and high quantum yield remains challenging for intracellular hypoxic imaging up to present. Herein, aqueous RTP nanoprobes consisting of naphthalene anhydride derivatives, cucurbit[7]uril (CB[7]), and organosilicon are reported via supermolecular confined methods. Benefiting from the noncovalent confinement of CB[7] and hydrolysis reactions of organosilicon, such small-sized RTP nanoprobes (5–10 nm) exhibit inherent tunable phosphorescence (from 400 to 680 nm) with microsecond second lifetimes (up to ∼158.7 μs) and high quantum yield (up to ∼30%). The as-prepared RTP nanoprobes illustrate excellent intracellular hypoxia responsibility in a broad range from ∼0.1 to 21% oxygen concentrations. Compared to traditional fluorescence mode, the SBR value (∼108.69) of microsecond-range time-resolved in vitroimaging is up to 2.26 times greater in severe hypoxia (<0.1% O2), offering opportunities for precision imaging analysis in a hypoxic environment.

Ocular neovascularization can result in devastating diseases that lead to marked vision impairment and eventual visual loss. In clinical implementation, neovascular eye diseases are first diagnosed by fluorescein angiography and then treated by multiple intravitreal injections, which nevertheless involves vision-threatening complications, as well as lack of real-time monitoring disease progression and timely assessment of therapeutic outcomes. To address this critical issue, we herein present a kind of theranostic agents made of peptide-functionalized silicon nanoparticles (SiNPs), suitable for simultaneous ocular neovascularization imaging and therapy. Typically, in addition to negligible toxicity and high specific binding ability to human retinal microvascular endothelial cells tube formation, the cyclo-(Arg-Gly-Asp-d-Tyr-Cys) (c-(RGDyC))-conjugated SiNPs (SiNPs-RGD) features efficacious antiangiogenic ability in wound healing migration, transwell migration, transwell invasion, and tube formation assays. Taking advantage of these unique merits, we further employ the SiNPs-RGD for labeling angiogenic blood vessels and neovascularization suppression, demonstrating obvious inhibition of new blood vessels formation in mouse corneas. These results suggest the SiNPs-RGD as a novel class of high-quality theranostic probes is suitable for simultaneous diagnosis and treatment in ocular neovascular diseases.