Perovskite Probe-Based Machine Learning Imaging Model for Rapid Pathologic Diagnosis of Cancers.

Accurately distinguishing tumor cells from normal cells is a key issue in tumor diagnosis, evaluation, and treatment. Fluorescence-based immunohistochemistry as the standard method faces the inherent challenges of the heterogeneity of tumor cells and the lack of big data analysis of probing images. Here, we have demonstrated a machine learning-driven imaging method for rapid pathological diagnosis of five types of cancers (breast, colon, liver, lung, and stomach) using a perovskite nanocrystal probe. After conducting the bioanalysis of survivin expression in five different cancers, high-efficiency perovskite nanocrystal probes modified with the survivin antibody can recognize the cancer tissue section at the single cell level. The tumor to normal (T/N) ratio is 10.3-fold higher than that of a conventional fluorescent probe, which can successfully differentiate between tumors and adjacent normal tissues within 10 min. The features of the fluorescence intensity and pathological texture morphology have been extracted and analyzed from 1000 fluorescence images by machine learning. The final integrated decision model makes the area under the receiver operating characteristic curve (area under the curve) value of machine learning classification of breast, colon, liver, lung, and stomach above 90% while predicting the tumor organ of 92% of positive patients. This method demonstrates a high T/N ratio probe in the precise diagnosis of multiple cancers, which will be good for improving the accuracy of surgical resection and reducing cancer mortality.

Magneto-Controlled Tubular Liquid Actuators with Pore Engineering for Liquid Transport and Regulation.

Liquid manipulation using tubular actuators finds diverse applications ranging from microfluidics, printing, liquid transfer to micro-reactors. Achieving flexible and simple regulation of manipulated liquid droplets during transport is crucial for the tubular liquid actuators to perform complex and multiple functions, yet it remains challenging. Here, a facile tubular actuator for directional transport of various liquid droplets under the control of an externally applied magnetic field is presented. The surfaces of the actuator can be engineered with submillimeter-sized through-hole pores, which enables the liquid droplet to be easily modulated in the transport process. Furthermore, the liquid actuator with featured through-hole pores is expanded to function as a switch in an integrated external electric circuit by magnetically controlling the motion of a conductive liquid droplet. This work develops a strategy for regulating liquid droplets in the tubular actuation systems, which may inspire ideas for designing functional liquid actuators with potential applications in microfluidics, microchemical reaction, liquid switch, and liquid robotics.

Ultrasensitive Detection of Cancer Biomarkers Using Photonic-Crystal-Enhanced Single-Molecule Imaging.

The rapid and sensitive quantification of low-abundance protein markers holds immense significance in early disease diagnosis and treatment. Single-molecule fluorescence imaging exhibits very high detection sensitivity and thus has great application potential in this area. The single-molecule signal, however, is often susceptible to interference from background noise due to its inherently weak intensity. A variety of signal amplification techniques based on cascading reactions have been developed to improve the signal-to-noise ratio of single-molecule imaging. Nevertheless, the operation of these methods is typically complicated and time-consuming, which limits the clinical application. Herein, we introduce an enzyme-free, photonic-crystal-based single-molecule (PC-SM) biochip for cost-effective, time-efficient, and ultrasensitive detection of disease markers. The PC-SM biochip can enhance the signal-to-noise ratio of single molecules by nearly 3-fold compared with unamplified samples, through coupling of the single-molecule photon energy with the optical band gap of the photonic crystal. We used the PC-SM biochip to detect the low-abundance leukemia inhibitory factor in the blood of pancreatic cancer patients and healthy people and achieved a detection limit of 2.0 pg/L and an AUC of 0.9067. The method exhibits exceptional sensitivity and specificity, showing great application potential in various clinical settings.

Machine Learning-Assisted High-Throughput Identification and Quantification of Protein Biomarkers with Printed Heterochains.

Advanced in vitro diagnosis technologies are highly desirable in early detection, prognosis, and progression monitoring of diseases. Here, we engineer a multiplex protein biosensing strategy based on the tunable liquid confinement self-assembly of multi-material heterochains, which show improved sensitivity, throughput, and accuracy compared to standard ELISA kits. By controlling the material combination and the number of ligand nanoparticles (NPs), we observe robust near-field enhancement as well as both strong electromagnetic resonance in polymer-semiconductor heterochains. In particular, their optical signals show a linear response to the coordination number of the semiconductor NPs in a wide range. Accordingly, a visible nanophotonic biosensor is developed by functionalizing antibodies on central polymer chains that can identify target proteins attached to semiconductor NPs. This allows for the specific detection of multiple protein biomarkers from healthy people and pancreatic cancer patients in one step with an ultralow detection limit (1 pg/mL). Furthermore, rapid and high-throughput quantification of protein expression levels in diverse clinical samples such as buffer, urine, and serum is achieved by combining a neural network algorithm, with an average accuracy of 97.3%. This work demonstrates that the heterochain-based biosensor is an exemplary candidate for constructing next-generation diagnostic tools and suitable for many clinical settings.

Spin population determines whether antiaromaticity can increase or decrease radical stability.

Aromaticity, as a classical and fundamental concept in chemistry, can enhance thermodynamic stability. In sharp contrast, a previous study showed that antiaromaticity rather than aromaticity can enhance the radical stability of α-methyl heterocyclic compounds. Here, we demonstrate a similar antiaromaticity-promoted radical stability when the methyl group is replaced by five-membered (alkyl)(amino)cyclics (AACs). More interestingly, when an AAC is fused with an antiaromatic ring, the radical stability could be either reduced or enhanced, depending on the spin population. Specifically, when the spin density is populated on an incoming antiaromatic 1,4-dihydro-1,4-diborinine moiety, the radical stability is enhanced whereas when the spin density is maintained on the original five-membered ring, the radical stability is reduced. Our findings highlight the importance of spin density in tuning the radical stability, inviting experimental chemists' verification.

Printed On-Chip Perovskite Heterostructure Arrays for Optical Switchable Logic Gates.

The use of optoelectronic devices for high-speed and low-power data transmission and computing is considered in the next-generation logic circuits. Heterostructures, which can generate and transmit photoresponse signals dealing with different input lights, are highly desirable for optoelectronic logic gates. Here, the printed on-chip perovskite heterostructures are demonstrated to achieve optical-controlled "AND" and "OR" optoelectronic logic gates. Perovskite heterostructures are printed with a high degree of control over composition, site, and crystallization. Different regions of the printed perovskite heterostructures exhibit distinguishable photoresponse to varied wavelengths of input lights, which can be utilized to achieve optical-controlled logic functions. Correspondingly, parallel operations of the two logic gates ("AND" and "OR") by way of choosing the output electrodes under the single perovskite heterostructure. Benefiting from the uniform crystallization and strict alignment of the printed perovskite heterostructures, the integrated 3 × 3 pixels all exhibit 100% logic operation accuracy. Finally, optical-controlled logic gates responding to multiwavelength light can be printed on the predesigned microelectrodes as the on-chip integrated circuits. This printing strategy allows for integrating heterostructure-based optical and electronic devices from a unit-scale device to a system-scale device.

Spatiotemporal-Dependent Confinement Effect of Bubble Swarms Enables a Fractal Hierarchical Assembly with Promoted Chirality.

The submarine-confined bubble swarm is considered an important constraining environment for the early evolution of living matter due to the abundant gas/water interfaces it provides. Similarly, the spatiotemporal characteristics of the confinement effect in this particular scenario may also impact the origin, transfer, and amplification of chirality in organisms. Here, we explore the confinement effect on the chiral hierarchical assembly of the amphiphiles in the confined bubble array stabilized by the micropillar templates. Compared with the other confinement conditions, the assembly in the bubble scenario yields a fractal morphology and exhibits a unique level of the chiral degree, ordering, and orientation consistency, which can be attributed to the characteristic interfacial effects of the rapidly formed gas/water interfaces. Thus, molecules with a balanced amphiphilicity can be more favorable for the promotion. Not limited to the pure enantiomers, chiral amplification of the enantiomer-mixed assembly is observed only in the bubble scenario. Beyond the interfacial mechanism, the fast formation kinetics of the confined liquid bridges in the bubble scenario endows the assembly with the tunable hierarchical morphology when regulating the amphiphilicity, aggregates, and confined spaces. Furthermore, the chiral-induced spin selectivity (CISS) effect of the fractal hierarchical assembly was systematically investigated, and a strategy based on photoisomerization was developed to efficiently modulate the CISS effect. This work provides insights into the robustness of confined bubble swarms in promoting a chiral hierarchical assembly and the potential applications of the resulting chiral hierarchical patterns in solid-state spintronic and optical devices.

Signaling pathways in colorectal cancer implications for the target therapies.

Colorectal carcinoma (CRC) stands as a pressing global health issue, marked by the unbridled proliferation of immature cells influenced by multifaceted internal and external factors. Numerous studies have explored the intricate mechanisms of tumorigenesis in CRC, with a primary emphasis on signaling pathways, particularly those associated with growth factors and chemokines. However, the sheer diversity of molecular targets introduces complexity into the selection of targeted therapies, posing a significant challenge in achieving treatment precision. The quest for an effective CRC treatment is further complicated by the absence of pathological insights into the mutations or alterations occurring in tumor cells. This study reveals the transfer of signaling from the cell membrane to the nucleus, unveiling recent advancements in this crucial cellular process. By shedding light on this novel dimension, the research enhances our understanding of the molecular intricacies underlying CRC, providing a potential avenue for breakthroughs in targeted therapeutic strategies. In addition, the study comprehensively outlines the potential immune responses incited by the aberrant activation of signaling pathways, with a specific focus on immune cells, cytokines, and their collective impact on the dynamic landscape of drug development. This research not only contributes significantly to advancing CRC treatment and molecular medicine but also lays the groundwork for future breakthroughs and clinical trials, fostering optimism for improved outcomes and refined approaches in combating colorectal carcinoma.

Lead-Chelating Intermediate for Air-Processed Phase-Pure FAPbI3 Perovskite Solar Cells.

Formamidinium-lead triiodide (FAPbI3) perovskite holds promise as a prime candidate in the realm of perovskite photovoltaics. However, the photo-active α-FAPbI3 phase, existing as a metastable state, is observable solely at elevated temperatures and is susceptible to degradation into the δ-phase in ambient air. Therefore, the attainment of phase-stable α-FAPbI3 in ambient conditions has become a crucial objective in perovskite research. Here, we proposed an efficient conversion process of PbI2 into the α-FAPbI3 perovskites in ambient air. This conversion was facilitated by the introduction of chelating molecules, which interacted with PbI2 to form an intermediate phase. Due to the reduced formation barrier resulting from the altered reaction pathway, this stable intermediate phase transitioned directly into α-FAPbI3 upon the deposition of the organic cation solution, effectively bypassing the formation of δ-FAPbI3. Consequently, the ambient-fabricated FAPbI3 perovskite solar cells (PSCs) exhibited an outstanding power conversion efficiency of 25.08 %, along with a high open-circuit voltage of 1.19 V. Furthermore, the unencapsulated devices demonstrated remarkable environmental stability. Notably, this innovative approach promises broad applicability across various chelating molecules, opening new avenues for further progress in the ambient air fabrication of FAPbI3 PSCs.

Droplet-based mechanical transducers modulated by the symmetry of wettability patterns.

Asymmetric mechanical transducers have important applications in energy harvesting, signal transmission, and micro-mechanics. To achieve asymmetric transformation of mechanical motion or energy, active robotic metamaterials, as well as materials with asymmetric microstructures or internal orientation, are usually employed. However, these strategies usually require continuous energy supplement and laborious fabrication, and limited transformation modes are achieved. Herein, utilizing wettability patterned surfaces for precise control of the droplet contact line and inner flow, we demonstrate a droplet-based mechanical transducer system, and achieve multimodal responses to specific vibrations. By virtue of the synergistic effect of surface tension and solid-liquid adhesion on the liquid dynamics, the droplet on the patterned substrate can exhibit symmetric/asymmetric vibration transformation when the substrate vibrates horizontally. Based on this, we construct arrayed patterns with distinct arrangements on the substrate, and employ the swarm effect of the arrayed droplets to achieve three-dimensional and multimodal actuation of the target plate under a fixed input vibration. Further, we demonstrate the utilization of the mechanical transducers for vibration management, object transport, and laser modulation. These findings provide a simple yet efficient strategy to realize a multimodal mechanical transducer, which shows significant potential for aseismic design, optical molding, as well as micro-electromechanical systems (MEMS).

Unveiling the Potential of Two-Terminal Perovskite/Organic Tandem Solar Cells: Mechanisms, Status, and Challenges.

Perovskite/organic tandem solar cells (PO-TSCs) demonstrate exceptional suitability for emerging applications such as building-integrated photovoltaics, wearable devices, and greenhouse farming. By leveraging the distinctive attributes of perovskite and organic materials, which encompass expanded solar spectrum utilization, chemically benign solubility, and soft nature, PO-TSCs position themselves as ideal candidates for high-performance semi-transparent photovoltaics (ST-PVs). Despite these advantages, their development significantly lags behind other perovskite-based counterparts, such as perovskite/perovskite, perovskite/silicon, and perovskite/Cu(In, Ga)Se2. To address existing challenges and unlock the full potential of PO-TSCs, an exploration of the fundamental mechanisms governing tandem photovoltaic devices is embarked. Delving into critical aspects such as charge generation/separation, energy level alignment, and material choices becomes pivotal for optimizing PO-TSC performance. The investigation of monolithic two-terminal PO-TSCs offers insights into achievements and barriers, recognizing the competitive landscape with other TSC counterparts. Further scrutiny of perovskite absorbers and organic absorbers in TSCs reveals strategies aimed at enhancing stability and efficiency. The discussion extends to interconnection layers, elucidating their role in optimizing light transmission and balancing carrier recombination. In conclusion, a compelling outlook on the dynamic landscape of PO-TSCs is presented, highlighting the remarkable efficiency progression and signaling their potential to revolutionize solar energy harvesting technologies.

In-Situ Cyclized Polyacrylonitrile as an Electron Selective Layer for n-i-p Perovskite Solar Cell with Enhanced Efficiency and Stability.

In situ cyclized polyacrylonitrile (CPAN) is developed to replace n-type metal oxide semiconductors (TiO2 or SnO2) as an electron selective layer (ESL) for highly efficient and stable n-i-p perovskite solar cells (PSCs). The CPAN layer is fabricated via facile in situ cyclization reaction of polyacrylonitrile (PAN) coated on a conducting glass substrate. The CPAN layer is robust and insoluble in common solvents, and possesses n-type semiconductor properties with a high electron mobility of 4.13×10-3 cm2 V-1 s-1. With the CPAN as an ESL, the PSC affords a power conversion efficiency (PCE) of 23.12 %, which is the highest for the n-i-p PSCs with organic ESLs. Moreover, the device with the CPAN layer holds superior operational stability, maintaining over 90 % of their initial efficiency after 500 h continuous light soaking. These results confirm that the CPAN layer would be a desirable low-cost and efficient ESL for n-i-p PSCs and other photoelectronic devices with high performance and stability.

Printed Divisional Optical Biochip for Multiplex Visualizable Exosome Analysis at Point-of-Care.

Rapid detection of various exosomes is of great significance in early diagnosis and postoperative monitoring of cancers. Here, a divisional optical biochip is reported for multiplex exosome analysis via combining the self-assembly of nanochains and precise surface patterning. Arising from resonance-induced near-field enhancement, the nanochains show distinct color changes after capturing target exosomes for direct visual detection. Then, a series of divisional nanochain-based biochips conjugated with several specific antibodies are fabricated through designed hydrophilic and hydrophobic patterns. Because of the significant wettability difference, one sample droplet is precisely self-splitting into several microdroplets enabling simultaneous identification of multiple target exosomes in 30 min with a sensitivity of 6 × 107 particles mL-1 , which is about two orders lower than enzyme-linked immunosorbent assay. Apart from the trace amount detection, excellent semiquantitative capability is demonstrated to distinguish clinical exosomes from glioblastoma patients and healthy people. This method is simple, versatile, and highly efficient that can be extended as a diagnostic tool for many diseases, promoting the development of liquid biopsy.

Bio-inspired optical structures for enhancing luminescence.

Luminescence is an essential signal for many plants, insects, and marine organisms to attract the opposite sex, avoid predators, and so on. Most luminescent living organisms have ingenious optical structures which can help them get high luminescent performances. These remarkable and efficient structures have been formed by natural selection from long-time evolution. Researchers keenly observed the enhanced luminescence phenomena and studied how these phenomena happen in order to learn the characteristics of bio-photonics. In this review, we summarize the optical structures for enhancing luminescence and their applications. The structures are classified according to their different functions. We focus on how researchers use these biological inspirations to enhance different luminescence processes, such as chemiluminescence (CL), photoluminescence (PL), and electroluminescence (EL). It lays a foundation for further research on the applications of luminescence enhancement. Furthermore, we give examples of luminescence enhancement by bio-inspired structures in information encryption, biochemical detection, and light sources. These examples show that it is possible to use bio-inspired optical structures to solve complex problems in optical applications. Our work will provide guidance for research on biomimetic optics, micro- and nano-optical structures, and enhanced luminescence.

Photochemically deoxygenating micelles for protecting TTA-UC against oxygen quenching.

Pluronic F127, P123 and cross-linked F127 diacrylate micelles are photochemically deoxygenating nanocapsules in which oxygen could be removed by photochemical reaction with a surfactant and efficient triplet-triplet annihilation photon upconversion (TTA-UC) can be achieved in air. The efficiency of TTA-UC under air is comparable to that under deoxygenated conditions.

Perovskite-based photodetector for real-time and quantitative monitoring of sports motion.

Reliable monitoring the movement amplitude and dynamics during sports exercise is significant for improving training results and preventing training wound. Here, we present a printed perovskite-based photodetector for real-time and quantitative monitoring of sports motion. The ordered nucleation and growth of perovskite crystals are regulated by the 4-acetamidothiophenol (AMTP) at the interface, which promotes the size of perovskite crystals into the micrometer. Benefiting from the uniformity of the AMTP-regulated MAPbI3, the as-prepared photodetector gives great photocurrent response under indoor light or outdoor light. During the exercise, real-time monitoring sports motion is achieved through detecting the illumination changing of photodetectors attaching on the wrist and ankles. Moreover, twelve kinds of common sports can be quantitatively analyzed with the detection of illumination changing on the photodetector. Such photodetector provides an efficient measurement method of wearable electronics for sports monitoring.

Direct writing concave structure on viscoelastic substrate for loading and releasing liquid on skin surface.

Droplet deposition on deformable matrix has a broad application prospect. Regular deposition and diffusion of droplet on the substrate is the key to prepare flexible concave structure. Direct writing technique is an advanced method for depositing ink droplet on various substrates, which could produce a variety of deposition forms. Meanwhile, direct writing technique has the characteristics of simplicity, convenience and strong controllability. In this work, patterned concave structure was fabricated with viscoelastic substrate by direct writing technology, depositing behavior of ink droplet, formation condition and shape control of concave structure were studied with viscoelastic substrate, and practical application of the patterned concave structure was explored in loading and releasing liquid on skin surface. This study provides an efficient method for the preparation and application of controllable concave surface.

Bioinspired "cage traps" for closed-loop lead management of perovskite solar cells under real-world contamination assessment.

Despite the remarkable progress made in perovskite solar cells, great concerns regarding potential Pb contamination risk and environmental vulnerability risks associated with perovskite solar cells pose a significant obstacle to their real-world commercialization. In this study, we took inspiration from the ensnaring prey behavior of spiders and chemical components in spider web to strategically implant a multifunctional mesoporous amino-grafted-carbon net into perovskite solar cells, creating a biomimetic cage traps that could effectively mitigate Pb leakage and shield the external invasion under extreme weather conditions. The synergistic Pb capturing mechanism in terms of chemical chelation and physical adsorption is in-depth explored. Additionally, the Pb contamination assessment of end-of-life perovskite solar cells in the real-world ecosystem, including Yellow River water and soil, is proposed. The sustainable closed-loop Pb management process is also successfully established involving four critical steps: Pb precipitation, Pb adsorption, Pb desorption, and Pb recycling. Our findings provide inspiring insights for promoting green and sustainable industrialization of perovskite solar cells.

Molecular Recognition-Modulated Hetero-Assembly of Nanostructures for Visualizable and Portable Detection of Circulating miRNAs.

Biomolecular markers, particularly circulating microRNAs (miRNAs) play an important role in diagnosis, monitoring, and therapeutic intervention of cancers. However, existing detection strategies remain intricate, laborious, and far from being developed for point-of-care testing. Here, we report a portable colorimetric sensor that utilizes the hetero-assembly of nanostructures driven by base pairing and recognition for direct detection of miRNAs. Following hybridization, two sizes of nanoparticles modified with single-strand DNA can be robustly assembled into heterostructures with strong optical resonance, exhibiting distinct structure colors. Particularly, the large nanoparticles are first arranged into nanochains to enhance scattering signals of small nanoparticles, which allows for sensitive detection and quantification of miRNAs without the requirement of target extraction, amplification, and fluorescent labels. Furthermore, we demonstrate the high specificity and single-base selectivity of testing different miRNA samples, which shows great potential in the diagnosis, staging, and monitoring of cancers. These heterogeneous assembled nanostructures provide an opportunity to develop simple, fast, and convenient tools for miRNAs detection, which is suitable for many scenarios, especially in low-resource setting.