Aggregate (Hoboken, N.J.)最新文献

The exploration of antibiotic-independent phototherapy strategies for the treatment of bacterial biofilm infections has gained significant attention. However, efficient eradication of bacterial biofilms remains a challenge. Herein, a self-regulated phototheranostic nanosystem with single wavelength-triggered photothermal therapy (PTT)/photodynamic therapy (PDT) transformation and oxygen supply for multimodal synergistic therapy of bacterial biofilm infections is presented. This approach combines a eutectic mixture of natural phase-change materials (PCMs) and an aggregation-induced emission (AIE) phototheranostic agent TPA-ICN to form colloidally stable nanopartcicles (i.e. AIE@PCM NPs). The reversible solid−liquid phase transition of PCMs facilitates the adaptive regulation of the aggregation states of TPA-ICN, enabling a switch between the energy dissipation pathways for enhanced PDT in solid PCMs or enhanced PTT in liquid PCMs. Additionally, oxygen-carrying thermoresponsive nanoparticles are also introduced to alleviate the hypoxic microenvironment of biofilms by releasing oxygen upon heating by AIE@PCM NPs with enhanced PTT. The nanosystem exhibits outstanding therapeutic efficacy against bacterial biofilms both in vitro and in vivo, with an antibacterial efficiency of 99.99%. This study utilizes a self-regulated theranostic nanoplatform with adaptive PTT/PDT transformation via the phase transition of PCMs and heat-triggered oxygen release, holding great promise in the safe and efficient treatment of bacterial biofilm infections.

Developing the sensitive point-of-care testing (POCT) of oncogenic nucleic acids from human papillomavirus (HPV) infection is essential in preventing cervical cancer, especially in resource-limited settings. Rolling circle amplification (RCA) is attractive in achieving POCT via nucleic acid-based aggregation under isothermal conditions. However, the influence of RCA product structure on the aggregation remains unexplored resulting in limited sensitivity. Here, a minimum secondary structured RCA technique (MSS-RCA) is developed by designing a unique circular template, demonstrating significantly enhanced detection sensitivity with only one amplification step and one primer under isothermal conditions. The amplification efficiency of MSS-RCA could be kinetically manipulated by controlling the secondary structure of the circular template. Introducing the invertase probe to MSS-RCA, HPV16 E6/E7 nucleic acid target was detected with a personal glucose meter (PGM) with a sensitivity of 5 fm (50 zmol in 10 µL). This integrated MSS-RCA-PGM detection system was successfully applied to detect HPV16 E6/E7 mRNA extracted from 54 cervical swab samples reaching a positive predictive value of 100.00% and negative predictive values of 96.00% (77.77% to 99.40%, 95% CI). MSS-RCA-PGM provides a sensitive POCT platform for the detection of nucleic acid biomarkers for screening of cervical cancer or other diseases.

Organic light-emitting diodes (OLEDs) based on multiple resonance-thermally activated delayed fluorescence (MR-TADF) have the advantages of high exciton utilization and excellent color purity. However, the large conjugated planarity of general MR-TADF emitters makes them easily aggregate in the form of π–π stacking, resulting in aggregation-caused quenching (ACQ) and the formation of excimers, which reduce exciton utilization efficiency and color purity. To address these issues, large shielding units can be incorporated to prevent interchromophore interactions, whereas the majority of reported molecules are limited to blue-green light emissions. This work proposes a strategy of incorporating steric hindrance groups at different sites of the B/N core to suppress interactions between chromophore, contributing to blue MR-TADF emitters with high photo-luminance quantum yields (PLQYs ≥ 95%) and narrow full width at half maximum (FWHM), and importantly, great suppression of the ACQ effect. Therefore, blue OLEDs achieve high external quantum efficiencies up to 34.3% and high color purity with FWHM of about 27 nm and CIE around (0.12, 0.15), even at a high doping concentration of 20 wt%.

With the development of aggregation-induced emission (AIE) materials, the drawbacks of conventional fluorescence materials subjected to aggregation-caused quenching (ACQ) have been resolved. This has allowed for the improvement of novel AIE fluorescent materials that exhibit enhanced photostability, a higher signal-to-noise ratio, and better imaging quality. Meanwhile, the enhanced phototherapeutic effect of AIE materials has garnered widespread attention in the realm of tumor treatment. The distinct physiological and anatomical characteristics of the urinary system make it suitable for the use of AIE materials. Additionally, AIE-based phototherapy provides a superior solution to deal with the weaknesses of conventional treatments for urologic neoplasms. In this review, the scientific advancement on the use of AIE materials in urinary system diseases since the emergence of the AIE concept is reviewed in detail. The review highlights the promise of AIE materials for biomarkers detection, fluorescence imaging (FLI) in vivo and in vitro, AIE-based phototherapy, and synergistic therapy from both diagnostic and therapeutic viewpoints. It is firmly believed that AIE materials hold immense untapped potential for the diagnosis and treatment of urologic disease, as well as all diseases of the human body.

The energy dissipation pathways of a photosensitizer for phototherapies, including photodynamic therapy (PDT) and photothermal therapy (PTT), compete directly with that of its fluorescence (FL) emission. Enriching heavy atoms on the π-conjugated systems and aggregation-caused quenching are two effective methods to turn off the FL emission of photosensitizers, which is expected to boost the intersystem crossing (for PDT) and nonradiative transition (for PTT) of photosensitizers for maximized phototherapeutic efficacy. Following this approach, an all-iodine-substituted polydiacetylene aggregate poly(diiododiacetylene) (PIDA) has been developed, which shows a superior near infrared absorption (ε_808nm = 26.1 g⁻¹ cm⁻¹ L) with completely blocked FL, as well as high efficiency of reactive oxygen species generation (nearly 45 folds of indocyanine green) and photothermal conversion (33.4%). To make the insoluble fibrillar PIDA aggregates favorable for systemic administration, they are converted into nanospheres through a pre-polymerization morphology transformation strategy. The in vivo study on a 4T1 tumor-bearing mouse model demonstrates that PIDA nanospheres can almost eliminate the tumor entirely in 16 days and prolong the survival time of mice to over 60 days, validating their effective phototherapeutic response through the strategy of inhibiting FL for boosted intersystem crossing and nonradiative transition.

The prevention of blindness from glaucoma requires multiple treatments to lower intraocular pressure. Here, human contact lenses are modified with highly porous metal-organic frameworks with sustained release of brimonidine for prolonged glaucoma treatment. Various metal-organic frameworks were screened for their attachment to lenses, loading with brimonidine, and drug-release properties. Optimized therapeutic ocular lenses conjugated with MIL-101(Cr) frameworks maintain optical transparency and power. Coating of lenses with MIL-101(Cr) nanoparticles reduced brimonidine washout with tears and ensured a gradual and localized release of the drug into the eyeball through the cornea. The hybrid lenses provided a 4.5-fold better decrease in eye pressure, compared by area under the curve (AUC) value to a commercially available brimonidine tartrate solution. Therapeutic lenses did not induce any notable eye irritation or corneal damage in vivo. The newly developed hybrid lenses are expected to provide a robust platform for the therapy and prevention of various ocular diseases.

Metalated covalent organic frameworks (COFs) for 2D and 3D topologies are continuously being developed, whereas metalated COFs with 1D topologies are still in their infancy. Here, a novel 1D phenanthroline-based COF containing 4,4-(1,10-phenanthroline-2,9-diyl)bis[benzaldehyde] (PBA) is reported (PAD-COF). Subsequently, a metalated 1D COF, Co SAS/PAD-COF, is constructed using the bidentate ligand properties of PBA and anchoring the single Co atoms in PAD-COF through a post-synthetic modification strategy. This complex significantly improved the photocatalytic performance of PAD-COF, and the CO yield of the optimized Co SAS/PAD-COF was stable at 3091 µmol g⁻¹ h⁻¹ with a selectivity of 93%, which is approximately 43.7 times that of the original PAD-COF. Experimental and theoretical results demonstrate the excellent CO₂ photoreduction activity of Co SAS/PAD-COF owing to the synergistic effect of single Co catalytic sites and PAD-COF. Among them, PAD-COF, as the host, adsorbs CO₂ molecules and loads single Co atoms. Meanwhile, Co atoms function as catalytic sites and promote the adsorption and activation of CO₂, while reducing the reaction energy barrier formed by the *COOH intermediates. Therefore, this unique metalated 1D COF provides a fresh approach to photocatalytic CO₂ reduction.

Developing dynamic color-tunable ultra-long room temperature phosphorescence (URTP) polymers with afterglow of over 1 s, photo-chromism, and multi-stimuli response for practical anti-counterfeiting and information security applications is attractive but very challenging. Herein, by doping multicolor phosphorescence pyridinium bromide L block or viologen-based photo-chromic V block into polyvinyl alcohol matrixes, the water-stimuli-responsive color-tunable URTP polymer films with afterglow of up to 8 s and the reversible viologen-based photochromic polymer films have been developed. More significantly, a series of dynamic color-tunable URTP polymer films with ultra-long afterglow of over 6 s, photo-chromism, and water-stimuli response have been successfully exploited by integrating L and V blocks into one polymer system. Mechanistic investigations have revealed that their photo-chromism mainly comes from the photo-generated viologen free radicals. Furthermore, their dynamic multilevel anti-counterfeiting applications have been demonstrated. These results pave the way to develop smarter multifunctional URTP materials for anti-counterfeiting and optical sensing.

Viologen, as a type of strong electron acceptor, is prone to undergo electron transfer (ET) and change color under external stimuli. However, due to the easy aggregation of viologen molecules, they usually suffer from poor fluorescence emission in the condensed phase. Herein, a new viologen derivative of VioCl₂·2Cl (1²⁺·2Cl) was designed and synthesized, in which the fluorescence was enhanced by introducing Me-β-CD to weaken the interactions between viologen molecules. Then a viologen-based host–guest supramolecule of 1²⁺@Me-β-CD was obtained by electrostatic interactions. Photo-/chemo-responded guest 1²⁺ supplies 1²⁺@Me-β-CD, a green and dark purple caused by intramolecular and intermolecular ET. Furthermore, 1²⁺@Me-β-CD displays an additional thermal responsive purple color. The triple chromic behaviors all exhibit excellent reversibility and cycling stability. As expected, 1²⁺@Me-β-CD exhibits strong photoluminescence (PL) in solid–liquid dual states, presenting an improved quantum yield (Φ) from 1²⁺ (Φ_s = 0.37%, Φ_l = 16.74%) to 1²⁺@Me-β-CD (Φ_s = 10.45%, Φ_l = 25.86%), and the fluorescence intensity can be dynamically modulated by light, heat, and acid/base vapors. The multi-responsive chromism and tunable fluorescence of 1²⁺@Me-β-CD allow for potential applications in information security and smart windows.

Zero-dimensional (0D) hybrid manganese halides have gained wide attention for the various crystal structures, excellent optical performance and scintillation properties compared with 3D lead halide perovskite nanocrystals. In this work, a new family of 0D hybrid manganese halides of A₂MnBr₄ (A = BzTPP, Br-BzTPP, and F-BzTPP) based on discrete [MnBr₄]²⁻ tetrahedral units is reported as highly efficient lead-free scintillators. Excited by UV or blue light, these hybrids emit bright green light originating from the d–d transition of Mn²⁺ with near-unity PLQY (99.5%). Significantly, high PLQY and low self-absorption render extraordinary radioluminescence properties with the highest light yield of 80,100 photons MeV⁻¹, which reached the climax of present hybrid manganese halides and surpassed most commercial scintillators. The radioluminescence intensity features a linear response to X-ray doses with a detection limit of 30 nGy_air s⁻¹, far lower than the requirement of medical diagnostic (5.5 µGy_air s⁻¹). X-ray imaging demonstrates ultrahigh spatial resolution of 14.06 lp mm⁻¹ and short afterglow of 0.3 ms showcasing promising application prospects in radiography. Overall, we demonstrated new hybrid manganese halides as promising scintillators for advanced applications in X-ray imaging with multiple superiorities of nontoxicity, facile-assembly process, high irradiation light yield, excellent resolution, and stability.