Atomic layer deposition paves the way for next-generation smart and functional textiles

As technology evolves and consumer needs diversify, textiles have become crucial to determining the future of fashion, sustainability, and functionality. Functional textiles, which not only provide comfort and aesthetics as traditional textiles but also endow textiles with special functions such as antibacterial, anti-odor, moisture absorption and perspiration, anti-ultraviolet (UV), flame-retardant, self-cleaning, and anti-static properties through technological innovation and upgrading, have attracted increasing attention because they satisfy the specific needs of people in different environments and occasions. However, functionality often occurs at the expense of comfort in existing functional products. Endowing textiles with excellent multi-functionality with marginal effects on comfort and wearability properties continues to be a challenge. Atomic layer deposition (ALD) paves the way for creating functional fabrics by enabling the formation of highly conforming inorganic/organic coatings over a large area with precise atomic-level film thickness control from a self-limiting reaction mechanism. Therefore, this paper introduces the reaction mechanism of ALD and the unique advantages of depositing inorganic nanofilms on fiber and textile surfaces. The factors influencing ALD and the commonly used ALD-derived technologies are then discussed. Subsequently, the research progress and breakthroughs in inorganic nanofilms prepared by ALD in conferring multifunctional properties on textile surfaces, such as antimicrobial, UV-resistant, heat-insulating, multifunctional wetting, structural coloring, thermoelectric elements, and flexible sensing, are reviewed. Finally, future developments and possible challenges of ALD for the large-scale production of multifunctional fabrics are proposed, which are expected to promote the development of next-generation advanced functional textiles.

Exploring the synergy between bioluminescence and nanomaterials: Innovations in analytical and therapeutic applications

The application of bioluminescent luciferin-luciferase systems for visualizing and stimulating various processes in living systems is of great interest due to its specific nature and high signal-to-noise ratio. Nanomaterials can finely manipulate multiple parameters of the bioluminescent systems, including the enzyme stability, intensity, and duration of the irradiation. Also, bioluminescence can affect the properties of a nanomaterial, namely, to carry out BRET, to trigger cascades of various photochemical transformations. Here we summarize cases of the interplay between nanomaterials and various bioluminescent systems to improve various biosensors, biovisualization in cellulo, in vivo, and for therapy over the past twenty years. We reviewed interactions between a wide range of nanomaterials and bioluminescent systems, including bacterial and genetically encoded luciferases. This review aims to serve as a comprehensive guide for developing bioluminescent multimodal nanoplatforms for analytic applications and therapy.

Defect-engineered magnetic bismuth nanomedicine for dual-modal imaging and synergistic lung tumor therapy

Bismuth sulfide (Bi2S3) nanomaterials are recognized for their potential in tumor therapy due to their narrow bandgap and low toxicity. However, limited photothermal conversion efficiency (PCE) and low carrier density restrict their broader application in photothermal cancer treatment. To address these challenges, we designed defect-engineered, magnetic-targeting Bi2S3-based photothermal nanoparticles, Fe3O4@Au@Bi2S3 nanorugbys (Fe3O4@Au@Bi2S3 NRs). These nanoparticles were developed using a layer-by-layer encapsulation strategy with sulfur vacancies (Vs) and Bi antisite defects (Bi replacing S, Bis), enhancing electron trapping and recombination to boost the near-infrared (NIR) response. The PCE of Fe3O4@Au@Bi2S3 NRs reached 44.34 %, which significantly improved their efficacy in photothermal treatment for lung tumors. Moreover, the polyvinylpyrrolidone (PVP) coating on the nanoparticles enabled efficient loading and pH-responsive release of doxorubicin hydrochloride (DOX), facilitating synergistic chemo-photothermal therapy. When exposed to an external magnetic field, the nanoparticles demonstrated strong magnetic targeting and enhanced computed tomography (CT) imaging capabilities, improving tumor treatment accuracy. Both in vitro and in vivo studies showed that this combined therapy effectively induced cancer cell apoptosis and inhibited tumor proliferation, showcasing outstanding anti-tumor performance. This study provides a promising strategy for enhancing chemo-photothermal therapy through defect-engineered, magnetic-targeted Fe3O4@Au@Bi2S3 nanoparticles, holding significant potential for clinical applications in tumor therapy.

Discovery of Pseudo-Luciferase Activity in Immunoglobulin G (IgG) and Its Application to the Detection of IgG Denaturation

Antibodies are used as diagnostics and as pharmaceuticals, but they are susceptible to degradation at various stages of the manufacturing process. Currently, there is insufficient technology to detect degraded (non-native) antibodies easily and rapidly, despite the degradation of an antibody negatively affecting the product quality, safety, and efficacy. Here, we have developed an assay based on biomolecule-catalyzing chemiluminescence (BCL) in which the native or non-native immunoglobulin G (IgG) itself catalyzes the oxidative luminescent reaction of an imidazopyrazinone-type luciferin and emits different colored light depending on the conformation of the IgG. In this BCL-based assay, the degree of IgG degradation can be detected by simply mixing the luciferin and reading the resulting emission wavelength.

Real-time bioluminescence imaging of nitroreductase in breast cancer bone metastasis

Bone metastasis is a leading cause of mortality in breast cancer patients. Monitoring biomarkers for bone metastasis in breast cancer is crucial for the development of effective interventional treatments. Despite being a highly vascularized tissue, the bone presents a particularly hypoxic environment. Tumor hypoxia is closely linked to increased levels of various reductases, including nitroreductase (NTR). Currently, there are few probes available to detect NTR levels in breast cancer bone metastases. Although bioluminescent imaging is promising due to its specificity and high signal-to-noise ratio, many probes face challenges such as short emission wavelengths, reliance on complex conditions like external adenosine triphosphate, or lack of tissue specificity. In this study, through "caging" the luciferase substrate with an NTR-responsive aromatic nitro recognition group, we developed a highly sensitive and selective NTR-sensitive bioluminescent probe. The resulting probe effectively detects NTR in breast cancer cells and enables real-time monitoring of NTR in a mouse model of breast cancer bone metastasis. Additionally, it can differentiate between primary and bone tumors, and allow continuous monitoring of NTR levels, thus providing valuable insights into bone tumor progression. This work provides a powerful tool for further understanding the biological functions of NTR in breast cancer bone metastasis.

Optical Detection Techniques for Biomedical Sensing: A Review of Printed Circuit Board (PCB)-Based Lab-on-Chip Systems

Lab on Printed Circuit Boards (Lab-on-PCB) technology has emerged as a promising platform, offering miniaturization, integration, and cost-effective fabrication for a wide range of sensing applications. This review explores the most common optical detection techniques implemented on printed circuit boards (PCBs), including absorbance, fluorescence, and chemiluminescence, discussing their working principles, advantages, and limitations in the context of PCB-based sensing. Additionally, evanescent wave generation is considered as an alternative optical approach with benefits for specific applications. Elements such as excitation sources, photodetectors, and the distinguishing characteristics of each method are analyzed to provide a comprehensive, but concise, overview of the field. Emphasis is placed on how the PCB platform influences the performance, sensitivity, and feasibility of these detection methods, highlighting relevant design considerations. This work aims to provide a solid foundation for researchers interested in optical sensing within this technology, serving as a reference for future developments and applications in PCB-based optical detection.

Bioluminescent imaging of an oomycete pathogen empowers chemical selections and rational fungicide applications

Fungicides play an indispensable role in ensuring food security. However, rational chemical selection and fungicide precision application guidance remain constrained by the limitations in real-time monitoring of tracking pathogens within plant tissues. In the current study, we generated a genetically stable Phytophthora infestans strain (PiLuc) expressing luciferase gene, which serves as a dual-mode quantification platform for both in vitro and in vivo throughput screening. Consequently, we designed a 96-well plate high-throughput screening system to assess compounds inhibitory efficacy using PiLuc. Crucially, bioluminescence imaging enabled visualization of PiLuc in potato leaves and tubers during early infection stage, which is invisible to the naked eye. Capitalizing on the semi non-destructive and visual advantages, we developed a system for fungicide bioavailability evaluation and dosage-response assessment in tuber tissues, integrating real-time dynamic monitoring of pathogen. The development of bioluminescent imaging of late blight pathogen establishes an enabling platform for high-throughput fungicide screening while improving the precision bioavailability assessments.

Protein Engineering for Spatiotemporally Resolved Cellular Monitoring

Protein engineering has been extensively applied to the development of genetically encoded reporters for spatiotemporally resolved monitoring of dynamic biochemical activity across cellular compartments in living cells. Genetically encoded reporters facilitate the visualization and recording of cellular processes, including transmission of signaling molecules, protease activity, and protein-protein interactions. In this review, we describe and assess common reporter motifs and protein engineering strategies for designing genetically encoded reporters. We also discuss essential parameters for evaluating genetically encoded reporters, along with future protein engineering opportunities in this field.

Empowering bacteria with light: Optogenetically engineered bacteria for light-controlled disease theranostics and regulation

Bacterial therapy has emerged as a promising approach for disease treatment due to its environmental sensitivity, immunogenicity, and modifiability. However, the clinical application of engineered bacteria is limited by differences of expression levels in patients and possible off-targeting. Optogenetics, which combines optics and genetics, offers key advantages such as remote controllability, non-invasiveness, and precise spatiotemporal control. By utilizing optogenetic tools, the behavior of engineered bacteria can be finely regulated, enabling on-demand control of the dosage and location of their therapeutic products. In this review, we highlight the latest advancements in the optogenetic engineering of bacteria for light-controlled disease theranostics and therapeutic regulation. By constructing a three-dimensional analytical framework of "sense-produce-apply", we begin by discussing the key components of bacterial optogenetic systems, categorizing them based on their photosensitive protein response to blue, green, and red light. Next, we introduce innovative light-producing tools that extend beyond traditional light sources. Then, special emphasis is placed on the biomedical applications of optogenetically engineered bacteria in treating diseases such as cancer, intestinal inflammation and systemic disease regulation. Finally, we address the challenges and future prospects of bacterial optogenetics, outlining potential directions for enhancing the safety and efficacy of light-controlled bacterial therapies. This review aims to provide insights and strategies for researchers working to advance the application of optogenetically engineered bacteria in drug delivery, precision medicine and therapeutic regulation.

Recombinant auto-bioluminescent Escherichia coli to monitor the progression of Escherichia coli infection in the embryonated chicken eggs

RESEARCH HIGHLIGHTS

Bioluminescence imaging enabled real-time, noninvasive tracking of a bioluminescent APEC infection in embryonated chicken eggs over time.Bioluminescence signals showed contrasting patterns for dead and surviving embryos.The ilux2-APEC showed a higher luminoscore than luxABCDE-APEC in inoculated embryonated chicken eggs.The in ovo bioluminescent signal from intact eggs effectively reflects the ex ovo signal following the take out of yolk and embryo.

The impact of common redox mediators on cellular health: a comprehensive study

Electrochemistry has become a key technique for studying biomolecular reactions and dynamics of living systems by using electron-transfer reactions to probe the complex interactions between biological redox molecules and their surrounding environments. To enable such measurements, redox mediators such as ferro/ferricyanide, ferrocene methanol, and tris(bipyridine) ruthenium(II) chloride are used. However, the impact of these exogeneous redox mediators on the health of cell cultures remains underexplored. Herein, we present the effects of three common redox mediators on the health of four of the most commonly used cell lines (Panc1, HeLa, U2OS, and MDA-MB-231) in biological studies. Cell health was assessed using three independent parameters: reactive oxygen species quantification by fluorescence flow cytometry, cell migration through scratch assays, and cell growth via luminescence assays. We show that as the concentration of mediator exceeds 1 mM, ROS increases in all cell types while cell viability plumets. In contrast, cell migration was only hindered at the highest concentration of each mediator. Our observations highlight the crucial role that optimized mediator concentrations play in ensuring accuracy when studying biological systems by electrochemical methods. As such, these findings provide a critical reference for selecting redox mediator concentrations for bioanalytical studies on live cells.

An optimized luciferin formulation for NanoLuc-based in vivo bioluminescence imaging

Bioluminescence imaging (BLI) is widely used in preclinical biomedical research for noninvasive tracking of cell populations and biochemical events in vivo. With recent improvements in BLI brightness from the engineering of bioluminescent enzymes (luciferases) and substrates (luciferins), optimizing luciferin formulations to maximize delivery and minimize toxicity becomes important, especially for marine coelenterazine-type luciferins with limited solubility. Here, we complete the characterization of a previously reported NanoLuc substrate, designated cephalofurimazine-9 (CFz9), and optimize its formulation with water-soluble excipients. We report a pH-controlled formulation of CFz9 enabling high-dose delivery to achieve peak brightness comparable to other furimazine analogs both inside and outside the brain while reducing toxicity. Thus, an optimized CFz9 formulation improves the performance and tolerability of whole-animal BLI with NanoLuc-based reporters.

The development of a low-toxic peroxyoxalate chemiluminescent system for light-emitting plants

Light-emitting plants (LEPs) represent a promising technology for harnessing nature's processes for sustainable illumination. However, ensuring the long-term stability and efficiency of the emission without compromising plant health is critical. To address these issues, the experiment explored the creation of a chemiluminescent reaction using ethyl vanillin, a food flavoring compound, as an alternative to commercial chemiluminescent products, which are carcinogenic. Divanillyl oxalate (DVO) was used as a precursor in the chemiluminescence system, combined with an organic solvent, NaOH, H2O2, and fluorescein dye. Light emissions were measured after applying the mixtures onto Epipremmum aureum leaves. Additionally, other organic solvents (triacetin, dimethyl phthalate (DMP), ethylene glycol, glycerol, and DMSO) were assessed in the chemiluminescence system. Results showed that the DVO-fluorescence system emitted light up to 7.98 × 105 a.u. when formulated with 0.5 mL of 70 mg/mL DVO, 0.5 mL fluorescein, and 0.5 mL of 3% (v/v) H2O2, 0.1 mL of 0.01 M NaOH in DMP:EG (1:3 v/v) with fluorescein dye. After foliar application, the intensity of light emitted by E. aureum sprayed with the DVO-fluorescence system reached a level that was 0.56 times the intensity of commercial products. Moreover, the emitted light remained visible to the naked eye for up to 60 min. The DVO chemiluminescence system was also effective in emitting light.

Role of calcium acetate in promoting Vibrio campbellii bioluminescence and alleviating salinity stress in Episcia cupreata

This study examines the role of calcium in regulating the bioluminescence of Vibrio campbellii PSU5986 and its potential to alleviate salt stress in plants, which has implications for developing light-emitting plants (LEPs). The effects of organic calcium acetate (C₄H₆CaO₄) were compared to inorganic calcium chloride (CaCl₂) and skim milk regarding their impact on bacterial bioluminescence and plant physiology. While skim milk induced the highest initial luminescence, both C₄H₆CaO₄ and CaCl₂ prolonged light emission for over 16 h. Notably, C₄H₆CaO₄ prevented leaf shrinkage, a condition observed with inorganic salts after 24 h. Periodic supplementation of C₄H₆CaO₄ (every 6 h) improved bacterial immobilization and colonization, extending luminescence over 4 cycles (24 h). Bacterial enumeration revealed colonization densities of approximately 6.82 × 106 CFU cm⁻2 within leaf tissues and 5.22 × 1011 CFU cm⁻2 on the leaf surface. Quantitative PCR analysis indicated that luxG exhibited significantly higher copy numbers than luxA and luxC, highlighting its critical role in bioluminescence through flavin reductase activity. Additionally, C₄H₆CaO₄ reduced salt-induced oxidative stress by increasing chlorophyll levels while decreasing carotenoid (40.00%), anthocyanin (36.94%), proline (14.13%), and malondialdehyde (21.84%) accumulation compared to NaCl-treated plants. These findings emphasize the potential of C₄H₆CaO₄ to sustain bacterial luminescence and enhance plant resilience, contributing to the advancement of LEP technology as a sustainable bioenergy alternative.

Deciphering the Luminescence Spectral Shape of an Oxyluciferin Analogue through a Mixed Quantum-Classical Approach

In this contribution, we present a computational study on the absorption and emission spectra of the cproxy- anion in water, an analogue of the firefly oxyluciferin phenolate keto form. This compound displays a broad absorption spectrum and a large Stokes shift, two features that remain elusive to computational approaches, preventing a complete understanding of the photophysics behind this molecule. Here we attempt a fully first-principles computation of both absorption and emission spectral shapes and positions, explicitly including the effect of soft molecular flexible modes and of the stiff vibrational motions as well as those of the solvent. Namely, we adopt a recently developed mixed-quantum classical approach, the so-called Adiabatic Molecular Dynamics-generalized vertical Hessian (Ad-MD|gVH) method, which has been revealed to be well suited to reproduce band shapes in condensed phases. We also explore the performance of DFT functionals to build the potential energy surfaces and investigate the possible role of interstate couplings. By this means, we are able to obtain a first-principles simulation of the emission band shape close to the experimental one, and we correctly reproduce the two-peak shape of the absorption spectrum, both in terms of their spacing and relative intensity. However, the low-energy band of the computed absorption spectrum is too narrow, and the Stokes shift is remarkably underestimated. Through a careful analysis of different computational settings, we are able to identify some key aspects that partly explain these discrepancies, including the limitations of TD-DFT to properly describe the electronic energy along the flexible torsional degree of freedom in the lowest-excited state and the key role of mutual polarization of the solvent and the dye.

CadmiLume: A Novel Smartphone-Based Bioluminescence Color-Tuning Assay and Biosensor for Cadmium and Heavy Metal Detection in Water Samples

Heavy metal contamination of soil and water is a growing environmental concern, especially mercury, lead, and cadmium. Therefore, fast and reliable methodologies to assess contamination in the field are in demand. However, many methodologies require laborious, expensive, and cumbersome equipment that is not convenient for rapid field analysis. Mobile phone technology coupled with bioluminescent assays provides accessible hands-on alternatives that has already been shown to be feasible. Previously, we demonstrated that firefly luciferases can be harnessed as luminescence color-tuning sensors for toxic metals. An assay based on such a principle was already successfully applied for teaching biochemistry laboratory lessons, which demonstrates the effect of cadmium on enzyme function based on bioluminescence color change. For analytical detection of cadmium in water, here, we developed a novel bioluminescence assay using the cadmium-sensitive Amydetes vivianii firefly luciferase coupled with a cell phone provided with a program to quantify cadmium concentration based on luminescence color discrimination. The application has proven to be efficient with high precision between 0.10 and 2 mM of cadmium, being appliable to diluted water samples (0.1-2 µM) upon concentration and relying on reference cadmium standards values. The light emitted by the reference standards and samples in a dark box is captured by the smartphone's camera, which, using computer vision, automatically quantifies cadmium according to the RGB color. CadmiLume is a simple and easy luminescent enzymatic biosensor for cadmium contamination in water samples, which instantaneously can provide results with the convenience of a smartphone in the palm of one's hands.

De novo luciferases enable multiplexed bioluminescence imaging

We leverage AI-powered de novo protein design to create a new generation of luciferase catalysts, termed the neoLux series, which exhibit superior properties over native luciferases. These features include compact size, robust stability, cofactor independence, efficient cellular expression, higher catalytic efficiency, and unique substrate orthogonality, marking a significant advancement beyond the limitations of native luciferases. Additionally, we computationally designed highly efficient neoLux-fluorescent protein FRET fusions capable of simultaneous multi-parametric imaging in cellulo and in vivo. Our pioneering approach has created a unified luminescent toolkit to allow for multi-colored tracking of cancer heterogeneity in vivo, paving the way for complex biological discovery.

Recent advances in multimodal mechanoluminescent sensors enabled by nanostructure design

Multiple modes of perception have evolved in creatures to help them survive in a highly complex world under different harsh environments. Inspired by this, multimodal sensing materials have been created as one of the most crucial elements to bridge artificial intelligence with reality. The well-organized integration of multiple independent stimuli in a single material rather than simple integration, is expected to increase the accuracy and multifunctional applications of sensing devices. However, achieving multifunction coupling through elaborate nanostructure and supramolecular design, still remains a challenge that attracts great attention. Under the framework of nanostructural design for a multimodal response, the coupling of mechanoluminescence ability and advanced stimulus-response, has been reported to realize comprehensive perception and multifunctional applications for more complex scenarios. Herein, this mini review briefly provides an overview on the latest advances of multimodal mechanoluminescent sensors, concentrating on the nanostructure design strategy for multifunctional coupling, including triboelectric compositing, supramolecular interfacial connection, and band structure modulation; as well as emphatically discussing the advantages of mechanoluminescence coupling with self-powered sensing, piezoresistive response, temperature/chemical detection, and the corresponding advanced tools for heterogeneous output decoupling. Finally, the conclusions and outlook of multimodal mechanoluminescent sensors are presented.

Engineering a thermophilic luciferase variant from Photuris pennsylvanica into a mesophilic-like enzyme for expanded applications potential

Luciferase, known for its exceptional catalytic bioluminescent properties, has been widely utilized in diverse applications within biotechnology and medical research. Currently, enhancing thermostability and catalytic activity is a primary focus for optimizing luciferase modifications to further expand its detection range and accuracy. This study revealed a highly thermostable luciferase variant from Photuris pennsylvanica, Ppe146-1H2, which inherently exhibits thermophilic enzyme characteristics that are not conducive for optimal catalytic performance in practical applications. Building upon structural analysis, this research engineered Ppe146-1H2 into Ppe146-LGR via the residue substitutions I422L, D435G, and I519R. Ppe146-LGR retained notably thermostability, exhibiting a melting temperature (Tm value) of 75.3 ± 0.3 °C. Additionally, the variant demonstrated efficient catalytic activity at moderate temperatures, exhibiting 3.8 and 3.7-fold higher catalytic efficiencies towards D-luciferin and ATP at 37 °C compared to Ppe146-1H2. Overall, Ppe146-LGR displayed mesophilic-like catalytic activity and thermophilic-like thermostability simultaneously. In addition to enhanced catalytic properties, Ppe146-LGR emitted longer-wavelength light (580 nm) and operated optimally at near-neutral pH, coordinating with the current demands of luciferase applications. Through validation via rapid bacterial detection and reporter gene assays, it has been demonstrated that Ppe146-LGR holds promise as a valuable tool in the field of bioluminescence technology.

Unveiling the potential of microbial bioluminescence for marine pollution monitoring: a review

Marine pollution threatens global ecosystems, underscoring the urgent need for robust and efficient monitoring systems. Microbial bioluminescence has emerged as a promising tool for pollution detection, offering unique advantages due to its simplicity, sensitivity, and ecological relevance. This review explores the fundamental principles of bacterial and dinoflagellate bioluminescence, ecological significance, and their applications in marine pollution monitoring. Bioluminescence-based detection systems are broadly categorized into whole-cell biosensors (WCBs) and enzyme-based biosensors. WCBs are further classified into recombinant organisms based WCBs (Class I and Class II WCBs) and wild-type organisms based WCBs (Class III WCBs), demonstrating distinct pollutant detection and stress-response monitoring capabilities. We highlight their potential to improve pollution monitoring strategies by critically evaluating these technologies. Integrating bioluminescence-based systems into current frameworks could significantly enhance the assessment of marine ecosystem health, facilitate timely pollution management, and support the conservation and sustainable use of marine resources.

Mechanisms and applications of bacterial luciferase and its auxiliary enzymes

Bacterial luciferase (LuxAB) catalyzes the conversion of reduced flavin mononucleotide (FMNH⁻), oxygen, and a long-chain aldehyde to oxidized FMN, the corresponding acid and water with concomitant light emission. This bioluminescence reaction requires the reaction of a flavin reductase such as LuxG (in vivo partner of LuxAB) to supply FMNH⁻ for the LuxAB reaction. LuxAB is a well-known self-sufficient luciferase system because both aldehyde and FMNH⁻ substrates can be produced by the associated enzymes encoded by the genes in the lux operon, allowing the system to be auto-luminous. This makes it useful for in vivo applications. Structural and functional studies have long been performed in efforts to gain a better understanding of the LuxAB reaction. Recently, continued exploration of the LuxAB reaction have elucidated the mechanisms of C4a-hydroperoxyflavin formation and identified key catalytic residues such as His44 that facilitates the generation of flavin intermediates important for light generation. Advancements in protein engineering and synthetic biology have improved the bioluminescence properties of LuxAB. Various applications of LuxAB for bioimaging, bioreporters, biosensing in metabolic engineering and real-time monitoring of aldehyde metabolites in biofuel production pathways have been developed during the last decade. Challenging issues such as achieving red-shifted emissions, optimizing the signal intensity and identifying mechanisms related to the generation of light-emitting species remain to be explored. Nevertheless, LuxAB continues to be a promising tool for diverse biotechnological and biomedical applications.

Machine Learning Nonadiabatic Dynamics: Eliminating Phase Freedom of Nonadiabatic Couplings with the State-Interaction State-Averaged Spin-Restricted Ensemble-Referenced Kohn-Sham Approach

Excited-state molecular dynamics (ESMD) simulations near conical intersections (CIs) pose significant challenges when using machine learning potentials (MLPs). Although MLPs have gained recognition for their integration into mixed quantum-classical (MQC) methods, such as trajectory surface hopping (TSH), and their capacity to model correlated electron-nuclear dynamics efficiently, difficulties persist in managing nonadiabatic dynamics. Specifically, singularities at CIs and double-valued coupling elements result in discontinuities that disrupt the smoothness of predictive functions. Partial solutions have been provided by learning diabatic Hamiltonians with phaseless loss functions to these challenges. However, a definitive method for addressing the discontinuities caused by CIs and double-valued coupling elements has yet to be developed. Here, we introduce the phaseless coupling term, Δ2, derived from the square of the off-diagonal elements of the diabatic Hamiltonian in the state-interaction state-averaged spin-restricted ensemble-referenced Kohn-Sham (SI-SA-REKS, briefly SSR)(2,2) formalism. This approach improves the stability and accuracy of the MLP model by addressing the issues arising from CI singularities and double-valued coupling functions. We apply this method to the penta-2,4-dieniminium cation (PSB3), demonstrating its effectiveness in improving MLP training for ML-based nonadiabatic dynamics. Our results show that the Δ2-based ML-ESMD method can reproduce ab initio ESMD simulations, underscoring its potential and efficiency for broader applications, particularly in large-scale and long-time scale ESMD simulations.

Automated Engineering Protein Dynamics via Loop Grafting: Improving Renilla Luciferase Catalysis

Engineering protein dynamics is a challenging and unsolved problem in protein design. Loop transplantation or loop grafting has been previously employed to transfer dynamic properties between proteins. We recently released a LoopGrafter Web server to execute the loop grafting task, employing eight computational tools and one database. The LoopGrafter method relies on the prediction of the local dynamic behavior of the elements to be transplanted and has successfully reconstructed previously engineered sequences. However, it was unclear whether catalytically competitive previously uncharacterized designs could be obtained by this method. Here, we address this question, showing how LoopGrafter generates viable loop-grafted chimeras of luciferases, how these chimeras encompass the activity of interest and unique kinetic properties, and how all this process is done fully automatically and agnostic of any previous knowledge. All constructed designs proved to be catalytically active, and the most active one improved the activity of the template enzyme by 4 orders of magnitude. The computational details and parameter optimization of the sequence pairing step of the LoopGrafter workflow are revealed. The optimized and experimentally validated loop grafting workflow available as a fully automated Web server represents a powerful approach for engineering catalytically efficient enzymes by modification of protein dynamics.

A Bioluminescent Probe for H2S Detection in Tumor Microenvironment

Hydrogen sulfide (H2S) is an endogenous gaseous signaling molecule that regulates various physiological functions, and its abnormal levels have been closely linked to the onset and progression of numerous diseases including renal cell carcinoma (RCC). RCC is the most common malignant tumor of the kidney, accounting for 85-90% of all kidney cancer cases. However, studies using H2S as a biomarker for monitoring RCC progression at the molecular level remain relatively limited. Most current H2S luminescent probes suffer from low sensitivity and often need external stimuli, such as cysteine, to artificially elevate H2S levels, thereby reducing their effectiveness in detecting H2S in cells or in vivo. Although bioluminescent imaging probes are gaining attention for their specificity and high signal-to-noise ratio, no existing probes are specifically designed for detecting H2S in RCC. Additionally, many bioluminescent probes face challenges such as short emission wavelengths or dependence on complex conditions such as external adenosine triphosphate (ATP). Herein, through "caging" the luciferin substrate QTZ with H2S recognition groups, a H2S-sensitive bioluminescent probe QTZ-N3 with good sensitivity (∼0.19 μM) and selectivity was prepared. QTZ-N3 can effectively detect endogenous H2S in 786-O-Nluc renal cancer cells and sensitively monitor H2S levels in the RCC xenograft nude mouse model without requiring stimuli like cysteine. Furthermore, QTZ-N3 allows for the real-time monitoring of H2S during tumor progression. This work lays a solid foundation for future understanding of the biological functions of H2S in vivo.

Stimuli-Responsive DNA Nanomachines for Intracellular Targeted Electrochemiluminescence Imaging in Single Cells

Electrochemiluminescence (ECL) microscopy has emerged as a powerful technique for single-cell imaging owing to its unparalleled background-free imaging advantages. However, controlled intracellular ECL imaging remains challenging. Here, we developed a stimuli-responsive self-assembled DNA nanomachine that enables the ECL imaging of intracellular target biomolecules in single cells. The ECL nanoprobe consists of an ECL nanoemitter constructed from Ru(bpy)3 2+-doped metal-organic framework as the nanoreactor core, with a DNA polymer hydrogel (DNAgel) shell acting as the stimuli-gated layer. The outer functionalized DNAgel of the ECL nanoprobe was specifically designed to block ECL generation and to dissociate by ATP molecules, thereby enabling selective recovery of ECL emission capability. Such an engineered stimuli-responsive nanomachine successfully achieved the targeted ECL imaging of intracellular ATP distribution with spatial resolution. In addition, ECL imaging of various intracellular biomolecules should be generalizable by simply changing the switching DNA sequence of the probe. Our research provided a reliable strategy for ECL microscopy within cells, which will broaden the application of ECL in single-cell and single-molecule profiling.

Inspired by nature: Bioluminescent systems for bioimaging applications

Bioluminescence is a natural process where biological organisms produce light through chemical reactions. These reactions predominantly occur between small-molecule substrates and luciferase within bioluminescent organisms. Bioluminescence imaging (BLI) has shown significant potential in biomedical research owing to its non-invasive, real-time observation and quantification. In this review, we introduced the chemical mechanism of bioluminescent systems and categorized several strategies that successfully addressed the native limitations, including improvements on the chemical structures of luciferase-luciferin bioluminescence system and bioluminescence resonance energy transfer (BRET) methods. In addition, we also reviewed and summarized recent advances in bioimaging applications. We hope that this review can provide effective guidance for the development and application of bioluminescent systems in the field of bioimaging.

Genetically Engineered Bacteria as A Living Bioreactor for Monitoring and Elevating Hypoxia-Activated Prodrug Tumor Therapy

Tirapazamine (TPZ), an antitumor prodrug, can be activated in hypoxic environment. It specifically targets the hypoxic microenvironment of tumors and produces toxic free radicals. However, due to the tumor is not completely hypoxic, TPZ often fails to effectively treat the entire tumor tissue, resulting in suboptimal therapeutic outcomes. Herein, a low pathogenic Escherichia coli TOP10 is utilized to selectively colonize tumor tissues, disrupt blood vessels, and induce thrombus formation, leading to the expansion of hypoxic region and improving the therapeutic effect of TPZ. Additionally, a thermosensitive hydrogel is constructed by Pluronic F-127 (F127), which undergoes gelation in situ at the tumor site, resulting in sustained release of TPZ. To monitor the therapeutic process, it is genetically modified TOP10 by integrating the bioluminescent system luxCDABE (TOP10-Lux). The bioluminescent signal is associated with tumor hypoxia enhancement and thrombus formation, which is beneficial for therapeutic monitoring with bioluminescence imaging. In the murine colon cancer model, the TOP10-Lux combined with TPZ-loaded F127 hydrogel effectively suppressed tumor growth, and the treatment process is efficiently monitored. Together, this work employs genetically modified TOP10-Lux to enhance the therapeutic efficacy of TPZ and monitor the treatment process, providing an effective strategy for bacteria-based tumor-targeted chemotherapy and treatment monitoring.

Holistic monitoring of Campylobacter jejuni biofilms with NanoLuc bioluminescence

Campylobacter jejuni, a major cause of foodborne zoonotic infections worldwide, shows a paradoxical ability to survive despite its susceptibility to environmental and food-processing stressors. This resilience is likely due to the bacterium entering a viable but non-culturable state, often within biofilms, or even initiating biofilm formation as a survival strategy. This study presents an innovative application of NanoLuc bioluminescence to accurately monitor the development of C. jejuni biofilms on various substrates, such as polystyrene plates, mucin-coated surfaces, and chicken juice matrices. Introduction of NanoLuc luciferase in a pathogenic C. jejuni strain enables rapid non-invasive holistic observation, capturing a spectrum of cell states that may comprise live, damaged, and viable but non-culturable populations. Our comparative analysis with established biofilm quantification methods highlights the specificity, sensitivity, and simplicity of the NanoLuc assay. The assay is efficient and offers precise cell quantification and thus represents an important complementary or alternative method to conventional biofilm monitoring methods. The findings of this study highlight the need for a versatile approach and suggest combining the NanoLuc assay with other methods to gain comprehensive insight into biofilm dynamics. KEY POINTS: • Innovative NanoLuc bioluminescence assay for sophisticated biofilm quantification. • Holistic monitoring of C. jejuni biofilm by capturing live, damaged and VBNC cells. • Potential for improving understanding of biofilm development and structure.

Bioluminescent Pseudomonas aeruginosa and Escherichia coli for whole-cell screening of antibacterial and adjuvant compounds

Continued efforts to discover new antibacterial molecules are critical to achieve a robust pre-clinical pipeline for new antibiotics. Screening of compound or natural product extract libraries remains a widespread approach and can benefit from the development of whole cell assays that are robust, simple and versatile, and allow for high throughput testing of antibacterial activity. In this study, we created and validated two bioluminescent reporter strains for high-throughput screening, one in Pseudomonas aeruginosa, and another in a hyperporinated and efflux-deficient Escherichia coli. We show that the bioluminescent strains have a large dynamic range that closely correlates with cell viability and is superior to conventional optical density (OD600) measurements, can detect dose-dependent antibacterial activity and be used for different drug discovery applications. We evaluated the assays' performance characteristics (signal to background ratio, signal window, Z' robust) and demonstrated their potential utility for antibiotic drug discovery in two examples. The P. aeruginosa bioluminescent reporter was used in a pilot screen of 960 repurposed compound libraries to identify adjuvants that potentiate the fluoroquinolone antibiotic ofloxacin. The E. coli bioluminescent reporter was used to test the antibacterial activity of bioactive bacterial supernatants and assist with bioassay-guided fractionation of the crude extracts.

A practical, biomimetic, one-pot synthesis of firefly luciferin

The bioluminescence reaction of firefly luciferase with D-luciferin has become an indispensable imaging technique in modern biology and life science experiments, but the high cost of D-luciferin is limiting its further application. Here, we report a practical, one-pot synthesis of D-luciferin from p-benzoquinone (p-BQ), L-cysteine methyl ester and D-cysteine, with an overall yield of 46%. Our route, which is six steps in length and proceeds via 2-cyano-6-hydroxybenzothiazole, is inspired by the mechanistic study of our previously reported biomimetic, non-enzymatic, one-pot formation of L-luciferin from p-BQ and L-cysteine. Advantages of our route include its high yield, low cost, use of only inexpensive, commercially available reagents, without requiring strictly anhydrous and oxygen-free conditions, and elevated temperatures.

mLumiOpto Is a Mitochondrial-Targeted Gene Therapy for Treating Cancer

Mitochondria are important in various aspects of cancer development and progression. Targeting mitochondria in cancer cells holds great therapeutic promise, yet current strategies to specifically and effectively destroy cancer mitochondria in vivo are limited. Here, we developed mitochondrial luminoptogenetics (mLumiOpto), an innovative mitochondrial-targeted luminoptogenetics gene therapy designed to directly disrupt the inner mitochondrial membrane potential and induce cancer cell death. The therapeutic approach included synthesis of a blue light-gated cationic channelrhodopsin in the inner mitochondrial membrane and coexpression of a blue bioluminescence-emitting nanoluciferase in the cytosol of the same cells. The mLumiOpto genes were selectively delivered to cancer cells in vivo by an adeno-associated virus carrying a cancer-specific promoter or cancer-targeted mAB-tagged exosome-associated adeno-associated virus. Induction with nanoluciferase luciferin elicited robust endogenous bioluminescence, which activated cationic channelrhodopsin, triggering cancer cell mitochondrial depolarization and subsequent cell death. Importantly, mLumiOpto demonstrated remarkable efficacy in reducing tumor burden and killing tumor cells in glioblastoma and triple-negative breast cancer xenograft mouse models. Furthermore, the approach induced an antitumor immune response, increasing infiltration of dendritic cells and CD8+ T cells in the tumor microenvironment. These findings establish mLumiOpto as a promising therapeutic strategy by targeting cancer cell mitochondria in vivo. Significance: mLumiOpto is a next generation optogenetic approach that employs selective delivery of genes to cancer cells to trigger mitochondrial depolarization, effectively inducing cell death and reducing tumor burden.

Biomimetic Electrodynamic Metal-Organic Framework Nanosponges for Augmented Treatment of Biofilm Infections

Electrodynamic therapy (EDT) is a promising alternative approach for antibacterial therapy, as reactive oxygen species (ROS) are produced efficiently in response to an electric field without relying on endogenous H2O2 and O2. However, the inherent toxicity of metallic catalysts and numerous bacterial toxins during the therapeutic process still hinder its development. Herein, biomimetic metal-organic (MOF@EV) nanosponges composed of ginger-derived extracellular vesicles (EVs), and electrodynamic metal-organic frameworks (MOFs) are developed for the eradication of bacterial infections and the absorption of toxins. The prolonged circulation time of MOF@EV in vivo facilitates their accumulation at infection sites. More interestingly, MOF@EV can behave as nanosponges and effectively prevent host cells from binding to bacterial toxins, thereby reducing damage to cells. Subsequently, the MOF@EV nanosponges are discovered to work as electro-sensitizers, which is confirmed through both theoretical calculation and experimental verification. As a result, ROS is continuously produced under the electric field to achieve effective EDT-mediated bacterial eradication. Meanwhile, the treatment process of MOF@EV in vivo is visualized in mice infected with luciferase-expressing Staphylococcus aureus (S. aureus), and excellent biofilm eradication capacity and detoxification efficiency are demonstrated in a subcutaneous abscess model. This work provides a promising strategy for the treatment of bacterial infections.

Harnessing Bioluminescence: A Comprehensive Review of In Vivo Imaging for Disease Monitoring and Therapeutic Intervention

The technique of using naturally occurring light-emitting reactants (photoproteins and luciferases] that have been extracted from a wide range of animals is known as bioluminescence imaging, or BLI. This imaging offers important details on the location and functional state of regenerative cells inserted into various disease-modeling animals. Reports on gene expression patterns, cell motions, and even the actions of individual biomolecules in whole tissues and live animals have all been made possible by bioluminescence. Generally speaking, bioluminescent light in animals may be found down to a few centimetres, while the precise limit depends on the signal's brightness and the detector's sensitivity. We can now spatiotemporally visualize cell behaviors in any body region of a living animal in a time frame process, including proliferation, apoptosis, migration, and immunological responses, thanks to BLI. The biological applications of in vivo BLI in nondestructively monitoring biological processes in intact small animal models are reviewed in this work, along with some of the advancements that will make BLI a more versatile molecular imaging tool.

Molecular Spies in Action: Genetically Encoded Fluorescent Biosensors Light up Cellular Signals

Cellular function is controlled through intricate networks of signals, which lead to the myriad pathways governing cell fate. Fluorescent biosensors have enabled the study of these signaling pathways in living systems across temporal and spatial scales. Over the years there has been an explosion in the number of fluorescent biosensors, as they have become available for numerous targets, utilized across spectral space, and suited for various imaging techniques. To guide users through this extensive biosensor landscape, we discuss critical aspects of fluorescent proteins for consideration in biosensor development, smart tagging strategies, and the historical and recent biosensors of various types, grouped by target, and with a focus on the design and recent applications of these sensors in living systems.

Harnessing luciferase chemistry in regulated cell death modalities and autophagy: overview and perspectives

Regulated cell death is a fate of cells in (patho)physiological conditions during which extrinsic or intrinsic signals or redox equilibrium pathways following infection, cellular stress or injury are coupled to cell death modalities like apoptosis, necroptosis, pyroptosis or ferroptosis. An immediate survival response to cellular stress is often induction of autophagy, a process that deals with removal of aggregated proteins and damaged organelles by a lysosomal recycling process. These cellular processes and their regulation are crucial in several human diseases. Exploiting high-throughput assays which discriminate distinct cell death modalities and autophagy are critical to identify potential therapeutic agents that modulate these cellular responses. In the past few years, luciferase-based assays have been widely developed for assessing regulated cell death and autophagy pathways due to their simplicity, sensitivity, known chemistry, different spectral properties and high-throughput potential. Here, we review basic principles of bioluminescent reactions from a mechanistic perspective, along with their implication in vitro and in vivo for probing cell death and autophagy pathways. These include applying luciferase-, luciferin-, and ATP-based biosensors for investigating regulated cell death modalities. We discuss multiplex bioluminescence platforms which simultaneously distinguish between the various cell death phenomena and cellular stress recovery processes such as autophagy. We also highlight the recent technological achievements of bioluminescent tools for the prediction of drug effectiveness in pathways associated with regulated cell death.

Bioluminescent Whole-Cell Bioreporter Bacterial Panel for Sustainable Screening and Discovery of Bioactive Compounds Derived from Mushrooms

This study presents a rapid and comprehensive method for screening mushroom extracts for the putative discovery of bioactive molecules, including those exhibiting antimicrobial activity. This approach utilizes a panel of bioluminescent bacteria, whose light production is a sensitive indicator of various cellular effects triggered by the extracts, including disruption of bacterial communication (quorum sensing), protein and DNA damage, fatty acid metabolism alterations, and oxidative stress induction. The bioassay's strength is its ability to efficiently analyze a large number of extracts simultaneously while also assessing several different mechanisms of toxicity, significantly reducing screening time. All samples analyzed exhibited more than one cellular effect, as indicated by the reporter bacteria. Four samples (C. cornucopioides, F. fomentarius, I. obliquus, and M. giganteus) displayed the highest number (six) of possible mechanisms of antibacterial activity. Additionally, combining extraction and purification protocols with a bioluminescent bacterial panel enables simultaneous improvement of the desired antimicrobial properties of the extracts. The presented approach offers a valuable tool for uncovering the diverse antimicrobial mechanisms of mushroom extracts.

Behind the glow: unveiling the nature of NanoLuc reactants and products

Due to the largely recognized utility of bioluminescence in many fields, a wide variety of luciferase-luciferin systems have been investigated in order to find the best-suited for a number of different applications. The collected knowledge has allowed the identification of a few necessary, or at least desirable, properties, such as bright luminescence, low background signal and small dimension of the enzyme that must exhibit structural stability at operating conditions. The NanoLuc-furimazine pair seems to meet all these requirements, but the mechanism of the reaction and the characteristics of the species responsible for the emission remain unknown. The aim of this study is to identify the luminescent product among the possible forms of oxidized furimazine and to understand how the chemical form and structure of the system, before and after the oxidation, are involved into the reaction mechanism and determine emission. To do this, we consider two possible forms of furimazine, the keto and the enol one, and test which of them is the most plausible candidate in the bioluminescence process on the basis of enzyme-substrate interactions from docking calculations. A similar procedure is repeated for three possible forms of the furimamide luminescent product, and their properties in the protein environment are then evaluated via QM/MM calculations. In contrast with previous indications, our simulations well support the involvement of the enol form of furimazine as reagent and point to the zwitterionic forms of furimamide as emissive species.

Direct and Ultrasensitive Bioluminescent Detection of Intact Respiratory Viruses

Respiratory viruses such as SARS-CoV-2, influenza, and respiratory syncytial virus (RSV) represent pressing health risks. Rapid diagnostic tests for these viruses detect single antigens or nucleic acids, which do not necessarily correlate with the amount of the intact virus. Instead, specific detection of intact respiratory virus particles may be more effective at assessing the contagiousness of a patient. Here, we report GLOVID, a modular biosensor platform to detect intact virions against a background of "free" viral proteins in solution. Our approach harnesses the multivalent display of distinct proteins on the surface of a viral particle to template the reconstitution of a split luciferase, allowing specific, single-step detection of intact influenza A and RSV virions corresponding to 0.1-0.3 fM of genomic units. The protein ligation system used to assemble GLOVID sensors is compatible with a broad range of binding domains, including nanobodies, scFv fragments, and cyclic peptides, which allows straightforward adjustment of the sensor platform to target different viruses.

Point-of-care testing for early-stage liver cancer diagnosis and personalized medicine: Biomarkers, current technologies and perspectives

Liver cancer is a highly prevalent and lethal form of cancer worldwide. In the absence of early diagnosis, treatment options for this disease are severely restricted. Recent advancements in genomics and bioinformatics have facilitated the discovery of a multitude of novel biomarkers that accurately depict an individual's disease diagnosis, progression, and treatment response. Leveraging these breakthroughs, personalized medicine employs an individual's biomarker profile to enable early detection of liver cancer and inform decisions regarding treatment selection, dosage determination, and prognosis assessment. The current lack of readily applicable, timely, and economically viable tools for biomarker analysis has hindered the incorporation of personalized medicine into regular clinical procedures. Over the past decade, significant advancements have been achieved in the field of molecular point-of-care testing (POCT) and amplification techniques, leading to substantial improvements in the diagnosis of liver cancer and the implementation of precision medicine. Instrument-free PCR technology or plasma PCR technology can shorten the complex procedure of in vitro detection of nucleic acid-based biomarkers. Also, compared to traditional ELISA, various nanomaterials modified with monoclonal antibodies to target proteins for recognition, capture, and detection have improved the efficiency of protein-based biomarker detection. These advances have reduced the time and cost of clinical detection of early-stage hepatocellular carcinoma and improved the efficiency of timely diagnosis and survival of suspected patients while reducing unnecessary testing costs and procedures. This review aims to provide a comprehensive overview of the current and emerging biomarkers employed in the early detection of liver cancer, as well as the advancements in point-of-care molecular testing technology and platforms. The primary objective is to assess their potential in facilitating the implementation of personalized medicine. This review ultimately revealed that the diagnosis of early-stage hepatocellular carcinoma not only requires sensitive biomarkers, but its various modifications and changes during the progression of cirrhosis to early-stage hepatocellular carcinoma will be a greater focus of our attention in the future. The rapid development of POCT has facilitated the opportunity to readily detect liver cancer in the general population in the future, and the integration of multi-pathway multiplexing and intelligent algorithms has improved the sensitivity and accuracy of early liver cancer biomarker detection. It is expected that the integration of point-of-care technology will be instrumental in the widespread adoption of personalized medicine in the foreseeable future.

Theoretical Insight into the Fluorescence Spectral Tuning Mechanism: A Case Study of Flavin-Dependent Bacterial Luciferase

Bioluminescence of bacteria is widely applied in biological imaging, environmental toxicant detection, and many other situations. Understanding the spectral tuning mechanism not only helps explain the diversity of colors observed in nature but also provides principles for bioengineering new color variants for practical applications. In this study, time-dependent density functional theory (TD-DFT) and quantum mechanics and molecular mechanics (QM/MM) calculations have been employed to understand the fluorescence spectral tuning mechanism of bacterial luciferase with a focus on the electrostatic effect. The spectrum can be tuned by both a homogeneous dielectric environment and oriented external electric fields (OEEFs). Increasing the solvent polarity leads to a redshift of the fluorescence emission maximum, λF, accompanied by a substantial increase in density. In contrast, applying an OEEF along the long axis of the isoalloxazine ring (X-axis) leads to a significant red- or blue-shift in λF, depending on the direction of the OEEF, yet with much smaller changes in intensity. The effect of polar solvents is directionless, and the red-shifts can be attributed to the larger dipole moment of the S1 state compared with that of the S0 state. However, the effect of OEEFs directly correlates with the difference dipole moment between the S1 and S0 states, which is directional and is determined by the charge redistribution upon deexcitation. Moreover, the electrostatic effect of bacterial luciferase is in line with the presence of an internal electric field (IEF) pointing in the negative X direction. Finally, the key residues that contribute to this IEF and strategies for modulating the spectrum through site-directed point mutations are discussed.

Amino-Acid-Encoded Supramolecular Nanostructures for Persistent Bioluminescence Imaging of Tumor

Bioluminescence imaging (BLI) is a powerful technique for noninvasive monitoring of biological processes and cell transplantation. Nonetheless, the application of D-luciferin, which is widely employed as a bioluminescent probe, is restricted in long-term in vivo tracking due to its short half-life. This study presents a novel approach using amino acid-encoded building blocks to accumulate and preserve luciferin within tumor cells, through a supramolecular self-assembly strategy. The building block platform called Cys(SEt)-X-CBT (CXCBT, with X representing any amino acid) utilizes a covalent-noncovalent hybrid self-assembly mechanism to generate diverse luciferin-containing nanostructures in tumor cells after glutathione reduction. These nanostructures exhibit efficient tumor-targeted delivery as well as sequence-dependent well-designed morphologies and prolonged bioluminescence performance. Among the selected amino acids (X = Glu, Lys, Leu, Phe), Cys(SEt)-Lys-CBT (CKCBT) exhibits the superior long-lasting bioluminescence signal (up to 72 h) and good biocompatibility. This study demonstrates the potential of amino-acid-encoded supramolecular self-assembly as a convenient and effective method for developing BLI probes for long-term biological tracking and disease imaging.

Optical Image Sensors for Smart Analytical Chemiluminescence Biosensors

Optical biosensors have emerged as a powerful tool in analytical biochemistry, offering high sensitivity and specificity in the detection of various biomolecules. This article explores the advancements in the integration of optical biosensors with microfluidic technologies, creating lab-on-a-chip (LOC) platforms that enable rapid, efficient, and miniaturized analysis at the point of need. These LOC platforms leverage optical phenomena such as chemiluminescence and electrochemiluminescence to achieve real-time detection and quantification of analytes, making them ideal for applications in medical diagnostics, environmental monitoring, and food safety. Various optical detectors used for detecting chemiluminescence are reviewed, including single-point detectors such as photomultiplier tubes (PMT) and avalanche photodiodes (APD), and pixelated detectors such as charge-coupled devices (CCD) and complementary metal-oxide-semiconductor (CMOS) sensors. A significant advancement discussed in this review is the integration of optical biosensors with pixelated image sensors, particularly CMOS image sensors. These sensors provide numerous advantages over traditional single-point detectors, including high-resolution imaging, spatially resolved measurements, and the ability to simultaneously detect multiple analytes. Their compact size, low power consumption, and cost-effectiveness further enhance their suitability for portable and point-of-care diagnostic devices. In the future, the integration of machine learning algorithms with these technologies promises to enhance data analysis and interpretation, driving the development of more sophisticated, efficient, and accessible diagnostic tools for diverse applications.

Luciferase-Loaded Calcium Phosphate Nanoparticles for Persistent Bioluminescence Imaging of Orthotopic Breast Tumors

Bioluminescence imaging (BLI) is an important noninvasive optical imaging technique that has been widely used to monitor many biological processes due to its high sensitivity, resolution, and signal-to-noise ratio. However, the BLI technique based on the firefly luciferin-luciferase system is limited by the expression of exogenous luciferase and the short half-life of firefly luciferin, which pose challenges for long-term tracking in vivo. To solve the problems, here we rationally designed an intelligent strategy for persistent BLI in tumors by combining luciferase-loaded calcium phosphate nanoparticles (Luc@CaP NPs) to provide luciferase and the probe Cys(SEt)-Lys-CBT (CKCBT) to slowly produce the luciferase substrate amino luciferin (Am-luciferin). Luc@CaP NPs constructed with CaP as a carrier could enable luciferase activity to be maintained in vivo for at least 12 h. And compared to the conventional substrate luciferin, CKCBT apparently prolonged the BL time by up to 2 h through GSH-induced intracellular self-assembly and subsequent protease degradation-induced release of Am-luciferin. We anticipate that this strategy could be applied for clinical translation in more disease diagnosis and treatment in the near future.

Tetrandrine activates STING/TBK1/IRF3 pathway to potentiate anti-PD-1 immunotherapy efficacy in non-small cell lung cancer

The efficacy of PD-1 therapy in non-small cell lung cancer (NSCLC) patients remains unsatisfactory. Activating the STING pathway is a promising strategy to improve PD-1 inhibitor efficacy. Here, we found tetrandrine (TET), an anti-tumor compound extracted from a medicinal plant commonly used in traditional Chinese medicine, has the ability to inhibit NSCLC tumor growth. Mechanistically, TET induces nuclear DNA damage and increases cytosolic dsDNA, thereby activating the STING/TBK1/IRF3 pathway, which in turn promotes the tumor infiltration of dendritic cells (DCs), macrophages, as well as CD8+ T cells in mice. In vivo imaging dynamically monitored the increased activity of the STING pathway after TET treatment and predicted the activation of the tumor immune microenvironment. We further revealed that the combination of TET with αPD-1 monoclonal antibody (αPD-1 mAb) yields significant anti-cancer effects by promoting CD8+ T cell infiltration and enhancing its cell-killing effect, which in turn reduced the growth of tumors and prolonged survival of NSCLC mice. Therefore, TET effectively eliminates NSCLC cells and enhances immunotherapy efficacy through the activation of the STING pathway, and combining TET with anti-PD-1 immunotherapy deserves further exploration for applications.

Engineering photodynamics for treatment, priming and imaging

Photodynamic therapy (PDT) is a photochemistry-based treatment approach that relies on the activation of photosensitizers by light to locally generate reactive oxygen species that induce cellular cytotoxicity, in particular for the treatment of tumours. The cytotoxic effects of PDT are depth-limited owing to light penetration limits in tissue. However, photodynamic priming (PDP), which inherently occurs during PDT, can prime the tissue microenvironment to adjuvant therapies beyond the direct PDT ablative zone. In this Review, we discuss the underlying mechanisms of PDT and PDP, and their application to the treatment of cancer, outlining how PDP can permeabilize the tumour vasculature, overcome biological barriers, modulate multidrug resistance, enhance immune responses, increase tumour permeability and enable the photochemical release of drugs. We further examine the molecular engineering of photosensitizers to improve their pharmacodynamic and pharmacokinetic properties, increase their molecular specificity and allow image guidance of PDT, and investigate engineered cellular models for the design and optimization of PDT and PDP. Finally, we discuss alternative activation sources, including ultrasound, X-rays and self-illuminating compounds, and outline key barriers to the clinical translation of PDT and PDP.

Unveiling Invisible Extracellular Vesicles: Cutting-Edge Technologies for Their in Vivo Visualization

Extracellular vesicles (EVs), nanosized lipid bilayer vesicles released by nearly all types of cells, play pivotal roles as intercellular signaling mediators with diverse biological activities. Their adaptability has attracted interest in exploring their role as disease biomarker theranostics. However, the in vivo biodistribution and pharmacokinetic profiles of EVs, particularly following administration into living subjects, remain unclear. Thus, in vivo imaging is vital to enhance our understanding of the homing and retention patterns, blood and tissue half-life, and excretion pathways of exogenous EVs, thereby advancing real-time monitoring within biological systems and their therapeutic applications. This review examines state-of-the-art methods including EV labeling with various agents, including optical imaging, magnetic resonance imaging, and nuclear imaging. The strengths and weaknesses of each technique are comprehensively explored, emphasizing their clinical translation. Despite the potential of EVs as cancer theranostics, achieving a thorough understanding of their in vivo behavior is challenging. This review highlights the urgency of addressing current questions in the biology and therapeutic applications of EVs. It underscores the need for continued research to unravel the complexities surrounding EVs and their potential clinical implications. By identifying these challenges, this review contributes to ongoing efforts to optimize EV imaging techniques for clinical use. Ultimately, bridging the gap between research advancements and clinical applications will facilitate the integration of EV-based theranostics, marking a crucial step toward harnessing the full potential of EVs in medical practice.

Ratiometric Readout of Bacterial Infections via a Lyophilized CRISPR-Cas12a Sensor with Color-Changeable Bioluminescence

The healthcare burden imposed by bacterial infections demands robust and accessible diagnostic methods that can be performed outside hospitals and centralized laboratories. Here, we report Pathogen Assay with Ratiometric Luminescence (PEARL), a sensitive and easy-to-operate platform for detecting pathogenic bacteria. The PEARL leveraged a color-changeable CRISPR-Cas12a sensor and recombinase polymerase amplification to elicit ratiometric bioluminescence responses to target inputs. This platform enabled robust and visualized identification of attomolar bacteria genome deoxyribonucleic acid according to the color changes of the reactions. In addition, the components of the color-changeable Cas12a sensor could be lyophilized for 3 month storage at ambient temperature and then be fully activated with the amplicons derived from crude bacterial lysates, reducing the requirements for cold-chain storage and tedious handling steps. We demonstrated that the PEARL assay is applicable for identifying the infections caused by Pseudomonas aeruginosa in different clinical specimens, including sputa, urines, and swabs derived from wounds. These results revealed the potential of PEARL to be used by untrained personnel, which will facilitate decentralized pathogen diagnosis in community- and resource-limited regions.

Bioimaging and prospects of night pearls-based persistence phosphors in cancer diagnostics

Inorganic persistent phosphors feature great potential for cancer diagnosis due to the long luminescence lifetime, low background scattering, and minimal autofluorescence. With the prominent advantages of near-infrared light, such as deep penetration, high resolution, low autofluorescence, and tissue absorption, persistent phosphors can be used for deep bioimaging. We focus on highlighting inorganic persistent phosphors, emphasizing the synthesis methods and applications in cancer diagnostics. Typical synthetic methods such as the high-temperature solid state, thermal decomposition, hydrothermal/solvothermal, and template methods are proposed to obtain small-size phosphors for biological organisms. The luminescence mechanisms of inorganic persistent phosphors with different excitation are discussed and effective matrixes including galliumate, germanium, aluminate, and fluoride are explored. Finally, the current directions where inorganic persistent phosphors can continue to be optimized and how to further overcome the challenges in cancer diagnosis are summarized.

Single-cell level LasR-mediated quorum sensing response of Pseudomonas aeruginosa to pulses of signal molecules

Quorum sensing (QS) is a communication form between bacteria via small signal molecules that enables global gene regulation as a function of cell density. We applied a microfluidic mother machine to study the kinetics of the QS response of Pseudomonas aeruginosa bacteria to additions and withdrawals of signal molecules. We traced the fast buildup and the subsequent considerably slower decay of a population-level and single-cell-level QS response. We applied a mathematical model to explain the results quantitatively. We found significant heterogeneity in QS on the single-cell level, which may result from variations in quorum-controlled gene expression and protein degradation. Heterogeneity correlates with cell lineage history, too. We used single-cell data to define and quantitatively characterize the population-level quorum state. We found that the population-level QS response is well-defined. The buildup of the quorum is fast upon signal molecule addition. At the same time, its decay is much slower following signal withdrawal, and the quorum may be maintained for several hours in the absence of the signal. Furthermore, the quorum sensing response of the population was largely repeatable in subsequent pulses of signal molecules.