Cyano-Coordinated Tin Halide Perovskites for Wearable Health Monitoring and Weak Light Imaging.

Low-toxicity tin halide perovskites with excellent optoelectronic properties are promising candidates for photodetection. However, tin halide perovskite photodetectors have suffered from high dark current owing to uncontrollable Sn2+ oxidation. Here, 2-cyanoethan-1-aminium iodide (CNI) is introduced in CH(NH2 )2 SnI3 (FASnI3 ) perovskite films to inhibit Sn2+ oxidation by the strong coordination interaction between the cyano group (C≡N) and Sn2+ . Consequently, FASnI3 -CNI films exhibit reduced nonradiative recombination and lower trap density. The self-powered photodetector based on FASnI3 -CNI exhibits low dark current (1.04 × 10-9 A cm-2 ), high detectivity (2.2 × 1013 Jones at 785 nm), fast response speed (2.62 µs), and good stability. Mechanism studies show the increase in the activation energy required for thermal emission and generated carriers, leading to a lower dark current in the FASnI3 -CNI photodetector. In addition, flexible photodetectors based on FASnI3 -CNI, exhibiting high detectivity and fast response speed, are employed in wearable electronics to monitor the human heart rate under weak light and zero bias conditions. Finally, the FASnI3 -CNI perovskite photodetectors are integrated with a 32 × 32 thin-film transistor backplane, capable of ultraweak light (170 nW cm-2 ) real-time imaging with high contrast, and zero power consumption, demonstrating the great potential for image sensor applications.

Pyroelectric-Accelerated Perovskite Photodetector for Picosecond Light Detection and Ranging.

Light detection and ranging (LiDAR) is indispensable in applications such as unmanned aerial vehicles, autonomous driving, and biomimetic robots. However, the precision and available distance of LiDAR are constrained by the speed and sensitivity of the photodetector, necessitating the use of expensive and energy-consuming avalanche diodes. To address these challenges, in this study, a pyroelectricity-based acceleration strategy with 2D-(graded 3D) perovskite heterojunction is proposed to achieve a record high speed (27.7 ns with an active area of 9 mm2, and 176 ps with an active area of 0.2 mm2) and high responsivity (0.65 A W-1) at zero bias. This success is attributed to the unique mechanism where the electrons from the pyroelectric effect at the Cl-rich 2D/3D interface directly recombine with excess holes during light-dark transitions, breaking speed limitations related to carrier mobility and capacitive effect. Furthermore, the introduced pyroelectric effect significantly enhances the photoresponse, resulting in a self-powered external quantum efficiency exceeding 100%. The study also demonstrates precise position detection at the centimeter level. In conclusion, this research presents a pioneering approach for developing high-speed photodiodes with exceptional sensitivity, mitigating energy and cost concerns in LiDAR applications.

Frequency-selective perovskite photodetector for anti-interference optical communications.

Free-space coupling, essential for various communication applications, often faces significant signal loss and interference from ambient light. Traditional methods rely on integrating complex optical and electronic systems, leading to bulkier and costlier communication equipment. Here, we show an asymmetric 2D-3D-2D perovskite structure device to achieve a frequency-selective photoresponse in a single device. By combining two electromotive forces of equal magnitude in the opposite directions, the device output is attenuated to zero under constant light illumination. Because these reverse photodiodes have different response speeds, the device only responds near a certain frequency, which can be tuned by manipulating the 2D perovskite components. The target device achieves an ultrafast response of 19.7/18.3 ns in the frequency-selective photoresponse range 0.8-9.7 MHz. This anti-interference photodetector can accurately transmit character and video data under strong light interference with a source intensity of up to 454 mW cm-2.

Two-Terminal Perovskite Optoelectronic Synapse for Rapid Trained Neuromorphic Computation with High Accuracy.

Emerging neural morphological vision sensors inspired by biological systems that integrate image perception, memory, and information computing are expected to transform the landscape of machine vision and artificial intelligence. However, stable and reconfigurable light-induced synaptic behavior always relies on independent gateport modulation. Despite its potential, the limitations of uncontrollable defects and ionic characteristics have led to simpler, smaller, and more integration-friendly two-terminal devices being used as sidelines. In this work, the synergy between ion migration barriers and readout voltage is proven to be the key to realizing stable, reconfigurable, and precisely controllable postsynaptic current in two-terminal devices. Following the same mechanism, optical and electrical signal synchronous triggering is proposed to serve as a preprocessing method to achieve a recognition accuracy of 96.5%. Impressively, the gradual ion accumulation during the training process induces photocurrent evolution, serving as a reference for the dynamic learning rate and boosting accuracy to 97.8% in just 10 epochs. The PSC modulation potential under short optical pulse of 20 ns is also revealed. This optoelectronic device with perception, memory, and computation capabilities can promote the development of new devices for future photonic neural morphological circuits and artificial vision.

Suppression of migration and invasion by taraxerol in the triple-negative breast cancer cell line MDA-MB-231 via the ERK/Slug axis.

As one of the triterpene extracts of Taraxacum, a traditional Chinese plant, taraxerol (TRX) exhibits antitumor activity. In this study, we evaluated the effects of TRX on the migration and invasion of MDA-MB-231 cells, analyzed the molecular mechanism through network pharmacology and molecular docking, and finally verified it by in vitro experiments. The results showed that TRX could inhibit the migration and invasion of MDA-MB-231 cells in a time- and concentration-dependent manner, while MAPK3 was the most promising target and could stably combine with TRX. In addition, the relative protein expression levels were detected by Western blot, and we observed that TRX could inhibit the migration and invasion of MDA-MB-231 cells via the ERK/Slug axis. Moreover, an ERK activator (tert-butylhydroquinone, tBHQ) partially reversed the suppressive effect of TRX on MDA-MB-231 cells. In conclusion, TRX inhibited the migration and invasion of MDA-MB-231 cells via the ERK/Slug axis.

Emerging Computational Micro-Spectrometers - From Complex System Integration to Simple In Situ Modulation.

The extensive applications of spectrum analysis across various fields have rendered the traditional desktop spectrometers unable to meet the market demand for portability and instantaneity. Reducing the size of spectrometers has become a topic of interest. Based on this trend, a novel type of computational spectrometer is developed and has been widely studied owing to its unique features. Such spectrometers do not need to integrate complex mechanical or optical structures, and most of them can achieve spectrum analysis by the properties of the material itself combines with the reconstruction algorithm. Impressively, a single-detector computational spectrometer has recently been successfully realized based on in situ modulation of material properties. This not only enables the further miniaturization of the device, but also means that the footprint-resolution limitation which has always existed in the field of hyperspectral imaging has been broken, opening a new era of image analysis. This review summarizes the classifications and principles of various spectrometers, compares the spectrum resolution performances of different types of spectrometers, and highlights the progress of computational spectrometers, especially the revolutionary single-detector spectrometer. It is expected that this review will provide a positive impact on expanding the boundary of spectrum analysis and move hyperspectral imaging forward.

A Single-Dot Perovskite Spectrometer.

There are significant applications for miniature on-chip spectrometers in many fields. However, at present, on-chip spectrometers have to utilize an integrated strategy to achieve spectral analysis, which undoubtedly squanders the photosensitive area and adds pressure to the miniaturization of the spectrometer. Here, a unique spectrometer design that adopts a single detection point with in situ modulation realized by the photogain control at various bias voltages is demonstrated. With micrometer-level footprints, this single-dot spectrometer processes a resolution of about 5 nm and a response time down to about 197 µs. This is the first in situ perovskite modulation strategy that breaks the footprint-resolution restriction of spectrum analysis and demonstrates a new design direction for functional perovskite devices.

Therapeutic potential of anti-miR29a in breast cancer patients with type 2 diabetes: an in vitro and xenograft mouse-model study.

Background: MicroRNAs (miRNAs) acting as tumour suppressors or oncogenes, known as oncomiRs, are a promising new focus in targeted therapies for cancer. Approximately 16% of breast cancer patients have pre-existing diabetes. Breast cancer with type 2 diabetes mellitus (BDM) is provided with its unique biological characteristics and clinical characteristics. This study primarily investigated the therapeutic potential and regulatory mechanism of miR-29a in patients with BDM. Methods: The significance of miR-29a in BDM was analyzed by real-time reverse transcriptase polymerase chain reaction (qRT-PCR) in breast tissues. A cell model for BDM was established by using MDA-MB-231 cells cultured in 3T3-L1 adipocytes cultured with high levels of glucose and insulin. A type 2 diabetes mellitus (T2DM) mouse model was induced in female BALB/c mice through a high-fat diet plus low doses of streptozotocin (STZ). The xenograft mouse-model for BDM was established on these T2DM mouse by using MDA-MB-231 cells. Then the biological effects of miR-29a knockdown mediated by lentivirus-shRNAs on cell proliferation, apoptosis, cell cycle, and migration were investigated. Results: Our results indicated that miR-29a was upregulated in patients with BDM, which correlated with a worse prognosis. In human breast cancer cells, miR-29a knockdown reduced cell proliferation and cell migration and invasion in BDM. In the T2DM xenograft, miR-29a knockdown suppressed MDA-MB-231 cells tumorigenesis and metastasis. We also demonstrated that miR-29a promoted BDM cell growth and metastasis by targeting Sirtuin 1 (SIRT1). Conclusions: Our findings indicated that anti-miR-29a inhibited cell proliferation and invasion in BDM by targeting SIRT1. We believe anti-miR-29a may represent a novel therapeutic approach for the management of patients with BDM.

2D Ruddlesden-Popper Perovskite with Ordered Phase Distribution for High-Performance Self-Powered Photodetectors.

2D Ruddlesden-Popper perovskites exhibit great potential in optoelectronic devices for superior stability compared with their 3D counterparts. However, to achieve a high level of device performance, it is crucial but challenging to regulate the phase distribution of 2D perovskites to facilitate charge carrier transfer. Herein, using a solvent additive method (adding a small amount of dimethyl sulfoxide (DMSO) in N,N-dimethylformamide (DMF)) combined with a hot-casting process, the phase distribution of (PEA)2 MA3 Pb4 I13 (PEA+  = C6 H5 CH2 CH2 NH3 + , MA+  = CH3 NH3 + ) perovskite can be well controlled and the Fermi level of perovskites along the film thickness direction can achieve gradient distribution. The increased built-in potential, oriented crystal, and improved crystal quality jointly contribute to the high photoresponse of devices in the entire response spectrum range. The optimum device exhibits a characteristic detection peak at 570 nm with large responsivity/detectivity (0.44 A W-1 /3.38 × 1012 Jones), ultrafast response speed with a rise/fall time of 20.8/20.6 µs, and improved stability. This work suggests the possibility of manipulating the ordered phase distribution of 2D perovskites toward high-performance and stable optoelectronic conversion devices.

Targeted Gene Silencing BRAF Synergized Photothermal Effect Inhibits Hepatoma Cell Growth Using New GAL-GNR-siBRAF Nanosystem.

Liver cancer is one of the most common malignancies worldwide. The RAF kinase inhibitors are effective in the treatment of hepatocellular carcinoma (HCC); therefore, inhibition of the BRAF/MEK/ERK pathway has become a new therapeutic strategy for novel HCC therapy. However, targeted specific delivery systems for tumors are still significant obstacle to clinical applications. Galactose (GAL) can target the asialoglycoprotein receptor (ASGPR) that is highly expressed on liver cancer cells. In this study, we designed a novel multifunctional nanomaterial GAL-GNR-siBRAF which consists of three parts, GAL as the liver cancer-targeting moiety, golden nanorods (GNR) offering photothermal capability under near infrared light, and siRNA specifically silencing BRAF (siBRAF). The nanocarrier GAL-GNR-siBRAF showed high siRNA loading capacity and inhibited the degradation of siRNA in serum. Compared with naked gold nanorods, GAL-GNR-siBRAF possessed lower biotoxicity and higher efficacy of gene silencing. Treatment with GAL-GNR-siBRAF significantly downregulated the expression of BRAF and impaired proliferation, migration, and invasion of liver cancer cells. Moreover, combinatorial photothermal effects and BRAF knockdown by GAL-GNR-siBRAF effectively given rise to tumor cell death. Therefore, our study developed a new type of targeted multi-functional nanomaterial GAL-GNR-siBRAF for the treatment of liver cancer, which provides ideas for the development of new clinical treatment methods.

Perovskite Transparent Conducting Oxide for the Design of a Transparent, Flexible, and Self-Powered Perovskite Photodetector.

Transparent and flexible electronic devices are highly desired to meet the great demand for next-generation devices that are lightweight, flexible, and portable. Transparent conducting oxides (TCOs), such as indium-tin oxide, serve as fundamental components for the design of transparent and flexible electronic devices. However, indium is rare and expensive. Herein, we report the fabrication of low-cost perovskite SrVO3 TCO films on transparent and flexible mica substrates and further demonstrate their utilization as a TCO electrode for building a transparent, flexible, and self-powered perovskite photodetector. Superior stable optical transparency and electrical conductivity are retained in SrVO3 after bending up to 105 cycles. Without an external power source, the constructed all-perovskite photodetector exhibits a high responsivity (42.5 mA W-1), fast response time (3.09/1.23 ms), and an excellent flexibility and bending stability after dozens of cycles of bending at an extreme 90° bending angle. Our results demonstrate that low-cost and structure-compatible transition metal-based perovskite oxides, such as SrVO3, as TCO electrodes have huge potential for building high-performance transparent, flexible, and portable smart electronics.

Nested Inverse Opal Perovskite toward Superior Flexible and Self-Powered Photodetection Performance.

Flexible and self-powered perovskite photodetectors have attracted tremendous research interests due to their applications in wearable and portable devices. However, the conventional planar structured photodetectors are always accompanied with limited device performance and undesired mechanical stability. Herein, a nested inverse opal (NIO) structured perovskite photodetector via a facile template-assisted spin-coating method is reported. The coupling effect of enhanced light capture, increased carrier transport, and improved perovskite film quality enables NIO device to exhibit superior photoresponse performance. The NIO photodetector exhibits a high responsivity of 473 mA W-1 and detectivity up to 1.35 × 1013 Jones at 720 nm without external bias. The NIO structure can efficiently release mechanical stress during the bending process and the photocurrent has no degradation even after 500 cycles of bending. Moreover, the unencapsulated NIO device can operate for over 16 d under ambient conditions, presenting a significantly enhanced environmental stability compared to the planar device. This work demonstrates that deliberate structural design is an effective avenue for constructing self-powered, flexible, and stable optoelectronic devices.