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Organic-inorganic metal halides have attracted great attention due to their tunable structural and spectroscopic properties. Here, two organic-inorganic hybrid manganese bromides, (TEMA) 2 MnBr 4 (TEMA = triethylmethylammonium) and (TEBA) 2 MnBr 4 (TEBA = benzyltriethylammonium), are synthesized using the evaporation crystallization method. Following a heat-induced phase transition at 363 K, the structure and optical properties of (TEMA) 2 MnBr 4 change but return to their initial state upon cooling to room temperature, as confirmed by X-ray diffraction, photoluminescence (PL), and Raman spectra. Meanwhile, (TEBA) 2 MnBr 4 , with a larger Mn-Mn distance, exhibits a higher photoluminescence quantum yield of 98.1% and greater thermal quenching temperature. However, due to the poorer thermal stability of the organic cation, the crystal melts at 400 K, leading to fluorescence quenching. White LEDs based on (TEMA) 2 MnBr 4 and (TEBA) 2 MnBr 4 are successfully fabricated with color rendering indices of 97.4 and 97.2, respectively. The investigation provides deep insights into the structural and optical properties of (TEMA) 2 MnBr 4 and (TEBA) 2 MnBr 4 , advancing research for LED display design by tuning organic cations.

In this Letter, erbium (Er 3+ ) and ytterbium (Yb 3+ ) codoped perovskite Cs 2 Ag 0.6 Na 0.4 In 0.9 Bi 0.1 Cl 6 microcrystal (MC) is synthesized and demonstrated systematically to the most prospective optical temperature sensing materials. A dual-mode thermometry based on fluorescence intensity ratio and fluorescence lifetime provides a self-reference and highly sensitive temperature measurement under dual wavelength excitation at a temperature from 300 to 470 K. Combined with the white-light emission derived from self-trapped excitons (STEs), the characteristic emission peak of Er 3+ ions can be observed under 405 nm laser excitation. The fluorescence intensity ratio (FIR) between perovskite and Er 3+ is used as temperature-dependent probe signal, of which maximum value for relative and absolute sensitivities reaches to 1.40% K -1 and 8.20 × 10 -2 K -1 . Moreover, Er 3+ luminescence becomes stronger with the feeding Yb 3+ increasing under 980 nm laser excitation. The energy transfer of Er 3+ and Yb 3+ is revealed by power-dependent photoluminescence (PL) spectroscopy, and the involved upconversion mechanism pertains to the two-photon excitation process. The results reveal that the Er 3+ /Yb 3+ codoped lead-free double perovskite MC is a good candidate for a thermometric material for the novel dual-mode design.

Both targeting and penetrating ability are the key characteristics for tissue probing and precise delivery. To construct an efficient nano probing and delivery system toward human epidermal growth factor receptor 2 (HER2) positive cancer, we established a nano liposomal system functionalized with a newly screened HER2 targeting peptide (HP2, YDLKEPEH) and the cell-penetrating peptide TAT simultaneously. Compared with the monofunctionalized liposomal probes, the dual-functional ones demonstrated a synergetic effect in cell uptake, drug delivery, and in vivo imaging. The improved efficacy of the synergetic system provides a prospective strategy for cancer diagnosis and therapy.

Mild acidic environment and angiogenesis are two typical characteristics of tumor. The specific response toward both lower pH and angiogenesis may enhance the targeting ability both for drug and diagnostic probe delivery. Herein, we present a kind of dual responding self-assembled nanotransformation material that is tumor angiogenesis targeting and pH triggered based on amphiphilic conjugation between peptides (STP) and aromatic molecules (tetraphenylethylene (TPE)). The morphology of the self-assembled peptide conjugates is responsibly changed from nanoparticles in neutral condition to nanofibers in acidic condition, which "turn on" the in vivo targeting imaging and accelerate the efficient drug delivery and in vivo therapy. On the basis of the well-controlled nanotransformation both in vitro and in vivo, we envisioned the successful demonstration of the responding materials would open a new avenue in turn on targeting imaging diagnostics and specific cancer therapeutics.

One switchable nanodelivery system was constructed. Liposomes were functionalized by a novel dual-recognition peptide STP, which is pH-responsive as well as the affinity ligand of tumor marker VEGFR2 (the angiogenesis marker vascular endothelial growth factor receptor 2). Efficient drug delivery and in vivo therapy could be "turned on" and accelerated only in the conditions of VEGFR2 overexpression and a mild acidic environment. We envisioned that the successful demonstration of this switchable nanocarrier system would open a new avenue on rapid cytoplasmic delivery for specific cancer diagnostics and therapeutics.

We present here a specific targeting nanocarrier system by functionalization of liposomes with one new type of breast cancer targeting peptide (H6, YLFFVFER) by a micromixer with high efficiency. Antitumor drugs could be successfully delivered into human epidermal growth factor receptor 2 (HER2) positive breast cancer cells with high efficiency in both in vivo and ex vivo models.