Abstract
Two-photon imaging in the near-infrared window holds huge promise for real life biological imaging due to the increased penetration depth. All-inorganic CsPbX(3) nanocrystals with bright luminescence and broad spectral tunability are excellent smart probes for two-photon bioimaging. But, the poor stability in water is a well-documented issue for limiting their practical use. Herein, we present the development of specific antibody attached water-resistant one-dimensional (1D) CsPbBr(3) nanowires, two-dimensional (2D) CsPbBr(3) nanoplatelets, and three-dimensional (3D) CsPbBr(3) nanocubes which can be used for selective and simultaneous two-photon imaging of heterogeneous breast cancer cells in the near IR biological window. The current manuscript reports the design of excellent photoluminescence quantum yield (PLQY), biocompatible and photostable 1D CsPbBr(3) nanowires, 2D CsPbBr(3) nanoplatelets, and 3D CsPbBr(3) nanocubes through an interfacial conversion from zero-dimensional (0D) Cs(4)PbBr(6) nanocrystals via a water triggered strategy. Reported data show that just by varying the amount of water, one can control the dimension of CsPbBr(3) perovskite crystals. Time-dependent transition electron microscopy and emission spectra have been reported to find the possible pathway for the formation of 1D, 2D, and 3D CsPbBr(3) nanocrystals from 0D Cs(4)PbBr(6) nanocrystals. Biocompatible 1D, 2D, and 3D CsPbBr(3) nanocrystals were developed by coating with amine-poly(ethylene glycol)-propionic acid. Experimental data show the water-driven design of 1D, 2D, and 3D CsPbBr(3) nanocrystals exhibits strong single-photon PLQY of ∼66-88% as well as excellent two-photon absorption properties (σ(2)) of ∼8.3 × 10(5)-7.1 × 10(4) GM. Furthermore, reported data show more than 86% of PL intensity remains for 1D, 2D, and 3D CsPbBr(3) nanocrystals after 35 days under water, and they exhibit excellent photostability of keeping 99% PL intensity after 3 h under UV light. The current report demonstrates for the first time that antibody attached 1D and 2D perovskites have capability for simultaneous two-photon imaging of triple negative breast cancer cells and human epidermal growth factor receptor 2 positive breast cancer cells. CsPbBr(3) nanocrystals exhibit very high two-photon absorption cross-section and good photostability in water, which are superior to those of commonly used organic probes (σ(2) = 11 GM for fluorescein), and therefore, they have capability to be a better probe for bioimaging applications.