To enhance the efficacy of photodynamic therapy, precisely modifying the absorption wavelength of the photosensitizer is of crucial importance. Herein, a simple yet effective conjugation-extension strategy was proposed. By extending...

Hydroxyl radicals (center dot OH), possessing extremely strong oxidative capability, play crucial roles in various fields. The detection of center dot OH is quite important but remains challenging. In this work, a series of quinoline-based fluorescent probes (F-1, F-2, F-3, and F-4) with aggregation enhanced emission (AEE) characteristics were designed and synthesized. All four probes exhibited pronounced turn-on fluorescence responses toward center dot OH with high selectivity and specificity, accompanied by distinct naked-eye recognition manifested as bright cyan fluorescence. Among them, probe F-4 showed the best sensing performance: upon the addition of 100 mu M center dot OH, its fluorescence intensity increased by 4.77-fold, and the limit of detection was as low as 124 nM within a linear detection range of 10 to 100 mu M. The mechanism of fluorescence enhancement may be attributed to the oxidation of the -CH2OH group in the probes by center dot OH to form -CH2CHO. Furthermore, a paper-based sensor was fabricated by simply depositing F-4 onto filter paper, enabling rapid naked-eye detection of center dot OH. This work provides a promising strategy for the development of novel AEE active fluorescent probes for center dot OH detection.

Incorporation of fused ring structure can effectively redshift the wavelength of host-guest doped organic room temperature phosphorescent (ORTP) materials, but would cause inefficient intersystem crossing (ISC) due to the increased singlet-triplet energy gap. To address the issue, we proposed a fused ring-fused heterocyclic ring (FR-FHR) guest strategy to achieve outstanding ORTP. In this strategy, fused ring (FR) contributes to the long wavelength emission, and fused heterocyclic ring (FHR) is enhances the ISC, thus enabling the simultaneous realization of long wavelength emission and high signal-to-background ratio (SBR). Three guest molecules-NTPH, OTPH, and STPH-were designed and synthesized, each comprising two distinct building blocks: a fused ring core and a fused heterocyclic ring substituent. When doped into a Benzophenone (BPO) host, the resulting BPO/XTPHs system showed outstanding phosphorescence lifetime (from 0.276 to 0.343 s) and long afterglow performance (at least 6 s of afterglow emission), which leads a remarkable SBR as high as 4945 after UV off 30 s by in vivo imaging system imaging. The excellent time-dependent characteristics and high SBR of BPO/XTPH highlight their potential for practical applications in afterglow imaging, such as fingerprint visualization.

Synergistic therapy of photothermal therapy (PTT) and photodynamic therapy (PDT) represents one of the most promising strategies for tumor treatment. However, the precise regulation of PTT and PDT remains challenging owing to their inherently competitive relationship. Herein, two pairs of synergistic phototherapy agents (PTAs) are developed based on the simple cationization strategy, which can regulate the proportion of PDT and PTT through the enhancement of intramolecular motion. Upon cationization, the photothermal conversion efficiency increased (45.0% of TPAY vs 53.2% of TPAYI, and 45.9% of TPNY vs 48.0% of TPNYI), while the reactive oxygen species (ROS) generation rate decreased correspondingly. With the synergistic PTAs, tumors ablation was achieved through the combined effects of ROS generation and photothermal heating, which further triggered immunotherapy and effectively inhibited the distant tumor. This study provides compelling evidence for a novel cationization strategy, which achieves triple functionality, i.e., increasing PTT contribution, enabling mitochondria targeting, and realizing multimodal synergistic tumor therapy.

Head and Neck Squamous Cell Carcinoma (HNSCC), characterized by a propensity for recurrence and metastasis, underscores the inadequacies of existing treatments. In this research, a liposome called DI@Lipo was developed to co-deliver cisplatin (DDP) and indocyanine green (ICG), aiming to trigger synergistic pyroptosis to enhance antitumor immunity. DI@Lipo cleverly harnessed the light-activated powers of ICG, combined them with DDP's tumor-killing ability, to induce activation of the NLRP3 inflammasome. This, in turn, spurred gasdermin D into action, setting off a fiery pyroptosis. This chain reaction triggered a substantial release of Damage-Associated Molecular Patterns (DAMPs) and inflammatory cytokines, which in turn stimulated dendritic cells to mature and attracted an influx of killer T cells. In murine models of HNSCC, this combination therapy not only effectively eliminated primary tumors but also induced a potent abscopal effect, suppressing untreated distant tumors. Importantly, this treatment improved overall survival rates without causing notable systemic toxicity. Additionally, the DI@Lipo platform facilitated fluorescence and photoacoustic imaging (PAI) for potential treatment monitoring. These findings highlight how DI@Lipo-triggered pyroptosis could effectively transform immunologically dormant tumors into responsive ones, presenting a practical therapeutic avenue to combat treatment resistance in head and neck squamous cell carcinoma.

Triggering near-infrared (NIR) room-temperature phosphorescence (RTP) poses a major challenge, because the narrow optical gap promotes nonradiative decay via thermal vibrations. Here, we report a series of high-performance RTP materials based on graphene nanoribbons, namely nHBT (n = 1-4). Unlike the modulation of fluorescence by extending π-conjugation, enhancing molecular conjugation more effectively induces red-shifted phosphorescence, enabling NIR emission. By doping nHBT in polyvinylpyrrolidone, NIR RTP with a maximum emission wavelength of 898 nm is achieved, exhibiting a quantum yield of 2.9% and a lifetime of 1.9 ms. Moreover, the rigid fused-ring framework suppresses molecular motions and nonradiative decay, resulting in a persistent afterglow even at 377 K. Well-dispersed NIR RTP nanoparticles were further obtained using polystyrene-b-poly(ethylene glycol) as the host and surfactant. In vivo studies demonstrate excellent capability to suppress background fluorescence, achieving a signal-to-background ratio as high as 47.3 ± 4.2. These results highlight rigid graphene nanoribbons as a versatile platform for high-performance NIR RTP and biophotonic applications.

Performance of two-dimensional conductive metal-organic frameworks (MOFs) in supercapacitor applications relies not only on their intrinsic structural properties but also on their mesostructures related to the size, shape, orientation, and aggregation morphology of crystallites assembled on a current collector. Nevertheless, the influence of crystallite orientation and aggregation morphology on the capacitive behavior remains poorly understood. Herein, the capacitive performance of dense face-on, sparse face-on, and edge-on Cu3(HHTP)2 (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) films, with controlled thicknesses and distinct crystallite morphologies, was systematically investigated in an aqueous electrolyte (3 M KCl). Face-on films showed a positive correlation between areal capacitance and thickness, indicating efficient electron and ion transport along their vertically aligned [001] channels. Although sparse face-on films exhibited a lower volumetric capacitance (98 F cm-3) than dense films (205 F cm-3), their isolated rod-like crystallites facilitated lateral interlayer ion diffusion, notably accelerating capacitive kinetics. Conversely, edge-on films displayed increasing areal capacitance only up to a limited thickness (883 nm), beyond which ion diffusion was impeded by a dense base layer formed by lateral intergrowth of vertically aligned sheet-like crystallites. Interestingly, despite featuring much shorter [001] channels, edge-on films showed slower capacitive kinetics than face-on films of comparable thicknesses, which was attributed to their more geometrically heterogeneous surface.

Excitation wavelength-dependent (Ex-De) chromophores, which exhibit changes in spectral composition with varying excitation wavelengths, have garnered significant interest. However, the pursuit of novel photoluminescence (PL) mechanisms and high luminescence quantum yields is facing huge challenges. Here, we discover that the introduction of a spinacine moiety to 2-(2-hydroxy-5-methylphenyl)benzothiazole, a traditional excited-state intramolecular proton transfer (ESIPT) fluorophore, results in a novel Ex-De PL molecule. The luminescent color of this compound can be effectively modulated from greenish-blue to yellow-green by adjusting either the excitation wavelength or temperature. Transient absorption and spectroelectrochemistry spectra elucidate the underlying mechanism, demonstrating the roles of ESIPT and proton-coupled electron transfer (PCET). When embedded in a poly(vinyl alcohol) film, the composite exhibits remarkable Ex-De PL behavior, achieving absolute fluorescence quantum yields of 55.6% (λ ex: 396 nm) and 69.6% (λ ex: 363 nm), as well as phosphorescence at room temperature. These properties highlight its potential for multiple encryption features, enhancing its application in anti-counterfeiting technologies.

Effectively improving the ability of electron transfer is the cornerstone of designing pure type I photosensitizers (PSs). At present, the attractive strategy is to introduce electron-rich structures to promote electron transfer capacity. Herein, we developed a novel core with fused heterocyclic rings (bicyclic 2-pyridone, BCP) based on which a series of excellent pure type I PSs can subsequently be constructed. BCP, with the fused heterocyclic rings, can act as an "electronic pool" for forming an electron-rich environment. Electrochemical experiments and theoretical calculations prove that BCP exhibits a more significant electron transfer phenomenon compared to the non-conjugated case. Based on BCP, a pure type I PS core, triphenylamine (electron donor, D) was introduced to produce a molecule (BCP-TPA) with near infrared emission and high type I PDT efficiency using the typical D-pi-D structure. BCP-TPA showed superior ability to produce pure type I ROS, which effectively inhibited tumor growth in in vivo experiments. This work provides a new core to synthesize pure type I PSs, combining fused heterocyclic rings to form an electron-rich environment.

The near-infrared (NIR) emission host-guest doped organic room temperature phosphorescence (ORTP) materials provide significant advantages and application for information anti-counterfeiting applications. The fused-ring structure of guest molecules is considered to be an effective method for redshirting the emission wavelength. Herein, we present a dual-fused-ring (DFR) guest strategy to develop NIR emission host-guest doped ORTP system. Five guest molecules with DFR effect were synthesized, incorporating a fused-ring core (1,2,3,4-tetraphenylnaphthalene, TPN) and various fused-ring substituents (benzene, naphthalene, anthracene, and pyrene). Using benzophenone (BPO) as the host, BPO/TPNs system exhibited excellent phosphorescence properties with emission wavelength ranging from 541 to 766 nm and lifetime from 27 to 355 ms. The experimental and theoretical studies prove that DFR strategy effectively lowers the lowest triplet excited state (T1) level and improve intersystem crossing (ISC) efficiency. The outstanding color- and time-dependent features of BPO/TPNs enable multi-anticounterfeiting applications. This work provides a facile and effective strategy for designing ORTP materials with both long wavelengths and extended lifetimes with DFR effect.

Nanopore sensing is a so-called label-free, single-molecule technology; however, multiple events of different molecules are recorded to obtain statistically robust data, which can limit both efficiency and sample use. To overcome these challenges, nanopore molecular ping-pong technology enables precise single-molecule manipulation, reducing systematic and stochastic errors by repeatedly measuring the same molecule. This review introduces the fundamentals and advancements of ping-pong technology, highlighting a recent breakthrough achieving over 10,000 recaptures of a single dsDNA molecule within minutes. This innovation not only minimizes sample requirements, which is critical for nonamplifiable samples, but also significantly enhances experimental precision. While current applications focus on dsDNA, extending this technology to protein and glycan analysis could transform nanopore research. Just as nanopore technology revolutionized DNA sequencing, it holds the potential to drive the development of nanopore-based protein and glycan sequencers, paving the way for groundbreaking advancements in molecular biology and biomedicine.

Based on the enhanced peroxidase-like activity of carbon dots nanozymes (CDszymes), with a specific oxidation reaction of D-amino acid oxidase catalysing the formation of H2O2 from D-amino acid, an ultrasensitive sensing platform, was constructed for the quantitative detection of D-amino acids in saliva. With the increase of D-amino acids concentration, the blue color of catalytic product gradually deepend, the fluorescence CDszymes gradually quenched, and the temperature gradually increased. Using D-alanine as D-amino acid models, the detection limits of D-alanine in colorimetric/photothermal/fluorescent mode were 0.3 μM, 1.8 μM, and 0.04 μM, respectively. The proposed detection platform exhibits promising application potential in clinical diagnostics. The exceptional sensing performance can be attributed to the utilization of CDszymes with outstanding POD activity. Revolving around the blind synthesis of CDszymes exhibiting high-efficiency POD activity, this study delved into the underlying mechanism governing the regulation of the POD activity of CDszymes by precursor functional groups. This work investigates the valence band theory to enhance the peroxidase-like of CDszymes, thereby offering a rational approach for designing CDszymes.

A large Stokes shift of up to 320 nm was achieved through intermolecular charge transfer, thus realizing the advantage of high signal-to-background ratio in biological imaging applications.

Metabolic engineering has a wide range of applications, spanning key sectors such as energy, pharmaceuticals, agriculture, chemicals, and environmental sustainability. Its core focus is on precisely modulating metabolic pathways to achieve efficient, sustainable, and environmentally friendly biomanufacturing processes, offering new possibilities for societal sustainable development. Gene attenuation is a critical technique within metabolic engineering, pivotal in optimizing metabolic fluxes and improving target metabolite yields. This review article discusses gene attenuation mechanisms, the applications across various biological systems, and implementation strategies. Additionally, we address potential future challenges and explore its potential to drive further advancements in the field.

The chemical investigation of the marine-derived fungus Penicillium sp. led to the isolation of three new secondary metabolites, including one isobenzofuranone (1) and two isochromenones (2 and 3), along with five known compounds (4-8). The structures of the new compounds, including their absolute configurations, were elucidated through comprehensive nuclear magnetic resonance, optical rotatory dispersion, and electronic circular dichroism spectral analyses. The antibacterial, cytotoxic, and α-glucosidase inhibitory activity of all compounds was assessed. Compounds 1 (IC₅₀ = 76.4 µM), 3 (IC₅₀ = 95.4 µM), and 4 (IC₅₀ = 88.3 µM) exhibited inhibitory effects against α-glucosidase, showing comparable activity to the positive control acarbose (IC₅₀ = 67.7 µM). Molecular docking revealed that these structurally analogous compounds exhibited similar binding modes within the active site.

Designing type I photosensitizers (PSs) with ease and precision is a promising approach to address the limitations of traditional photodynamic therapy (PDT) within the hypoxic tumor microenvironment. An effective strategy to achieve type I PSs involves adjusting the energy levels of triplet (T-1) states to inhibit type II PDT, ensuring they are lower than those required for singlet oxygen (O-1(2)) production. Herein, we report an E/Z isomer strategy to precisely regulate the type of reactive oxygen species (ROS) generated, thereby promoting the generation of type I PDT. Two pairs of E/Z isomers of tetraphenyl-1,3-butadiene (TPB) derivatives have been synthesized, which serve as the core of aggregation-induced emission (AIE) materials, exhibiting a typical donor-pi-acceptor structure. These isomers were obtained successfully via silica gel column chromatography. The E isomer demonstrated superior ROS generation efficiency compared with the Z isomer, attributed to its higher intersystem crossing (ISC). Meanwhile, the T-1-S-0 energy gap of the E isomer was smaller than that of O-2, effectively preventing the generation of O-1(2) through the type II process. The E/Z isomer strategy represents a promising avenue for the facile preparation of type I PDT agents and contributes to our understanding of the underlying mechanisms.

Background Microbial engineering aims to enhance the ability of bacteria to produce valuable products, including vitamin B-6 for various applications. Numerous microorganisms naturally produce vitamin B-6, yet the metabolic pathways involved are rigorously controlled. This regulation by the accumulation of vitamin B-6 poses a challenge in constructing an efficient cell factory. Results In this study, we conducted transcriptome and metabolome analyses to investigate the effects of the accumulation of pyridoxine, which is the major commercial form of vitamin B-6, on cellular processes in Escherichia coli. Our omics analysis revealed associations between pyridoxine and amino acids, as well as the tricarboxylic acid (TCA) cycle. Based on these findings, we identified potential targets for fermentation optimization, including succinate, amino acids, and the carbon-to-nitrogen (C/N) ratio. Through targeted modifications, we achieved pyridoxine titers of approximately 514 mg/L in shake flasks and 1.95 g/L in fed-batch fermentation. Conclusion Our results provide insights into pyridoxine biosynthesis within the cellular metabolic network for the first time. Our comprehensive analysis revealed that the fermentation process resulted in a remarkable final yield of 1.95 g/L pyridoxine, the highest reported yield to date. This work lays a foundation for the green industrial production of vitamin B-6 in the future.