The low-efficiency cellular uptake property of current nanoparticles greatly restricts their application in the biomedical field. Herein, we demonstrate that novel virus-like mesoporous silica nanoparticles can easily be synthesized, showing greatly superior cellular uptake property. The unique virus-like mesoporous silica nanoparticles with a spiky tubular rough surface have been successfully synthesized via a novel single-micelle epitaxial growth approach in a low-concentration-surfactant oil/water biphase system. The virus-like nanoparticles’ rough surface morphology results mainly from the mesoporous silica nanotubes spontaneously grown via an epitaxial growth process. The obtained nanoparticles show uniform particle size and excellent monodispersity. The structural parameters of the nanoparticles can be well tuned with controllable core diameter (∼60–160 nm), tubular length (∼6–70 nm), and outer diameter (∼6–10 nm). Thanks to the biomimetic morphology, the virus-like nanoparticles show greatly superior cellular uptake property (invading living cells in large quantities within few minutes, <5 min), unique internalization pathways, and extended blood circulation duration (t1/2 = 2.16 h), which is much longer than that of conventional mesoporous silica nanoparticles (0.45 h). Furthermore, our epitaxial growth strategy can be applied to fabricate various virus-like mesoporous core–shell structures, paving the way toward designed synthesis of virus-like nanocomposites for biomedicine applications.

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Lanthanide doped core-multishell structured NaGdF4:Yb,Er@NaYF4:Yb@NaGdF4:Yb,Nd@NaYF4@NaGdF4:Yb,Tm@NaYF4 nanoparticles with power-density independent orthogonal excitations-emissions upconversion luminescence (UCL) were fabricated for the first time. The optical properties of these core-multishell structured nanoparticles were related to the absorption filtration effect of the NaGdF4:Yb,Tm layer. By tuning the thickness of the filtration layer, the nanoparticles can exhibit unique two independent groups of UCL: Tm(3+) prominent UV/blue (UV=ultraviolet) UCL under the excitation at 980 nm and Er(3+) prominent green/red UCL under the excitation at 796 nm. The filtration-shell mediated orthogonal excitations-emissions UCL are power-density independent. As a proof of concept, the core-multishell nanoparticles are used in multi-dimensional security design and imaging-guided combined photodynamic therapy and chemotherapy.