Exploring Electron Transfer Mechanism in Synergistic Interactional Reduced Polyoxometalate-Based Cu(I)-Organic Framework for Photocatalytic Removal of U(VI).

Photocatalytic reduction of U(VI) is a promising method for removing uranium containing pollutants. However, using polyoxometalate-based metal-organic frameworks (POMOFs) for photoreduction of U(VI) is rare, and the relevant charge transfer pathway is also not yet clear. In this article, we demonstrate a highly efficient strategy and revealed a clearly electron transfer pathway for the photoreduction of U(VI) with 99% removal efficiency by using a novel POMOF, [Cu(4,4'-bipy)]5·{AsMo4VMo6VIV2VO40(VIVO)[VIVO(H2O)]}·2H2O (1), as catalyst. The POMOF catalyst was constructed by the connection of reduced {AsMo10V4} clusters and Cu(I)-MOF chains through Cu-O coordination bonds, which exhibits a broader and stronger light absorption capacity due to the presence of reduced {AsMo10V4} clusters. Significantly, the transition of electrons from Cu(I)-MOF to {AsMo10V4} clusters (Cu → Mo/V) greatly inhibits the recombination of photogenerated carriers, thereby advancing electron transfer. More importantly, the {AsMo10V4} clusters are not only adsorption sites but also catalytically active sites. This causes the fast transfer of photogenerated electrons from Mo/V to UO22+(Mo/V → O → U) via the surface oxygen atoms. The shorter electron transmission distance between catalytic active sites and UO22+ achieves faster and more effective electron transport. All in all, the highly effective photocatalytic removal of U(VI) using the POMOF as a catalyst is predominantly due to the synergistic interaction between Cu(I)-MOFs and reduced {AsMo10V4} clusters.

Design, synthesis, and biological evaluation of gambogenic acid derivatives: Unraveling their anti-cancer effects by inducing pyroptosis.

Gambogenic acid (GNA), a caged xanthone derived from Garcinia hanburyi, exhibits a wide range of anti-cancer properties. The caged skeleton of GNA serves as the fundamental pharmacophore responsible for its antitumor effects. However, limited exploration has focused on the structural modifications of GNA. This study endeavors to diversify the structure of GNA and enhance its anti-cancer efficacy. Sulfoximines, recognized as pivotal motifs in medicinal chemistry due to their outstanding properties, have featured in several anti-cancer drugs undergoing clinical trials. Accordingly, a series of 33 GNA derivatives combined with sulfoximines were synthesized and evaluated for their anti-cancer effects against MIAPaCa2, MDA-MB-231, and A549 cells in vitro. The activity screening led to the identification of compound 12k, which exhibited the most potent anti-cancer effect. Mechanistic studies revealed that 12k primarily induced pyroptosis in MIAPaCa2 and MDA-MB-231 cells by activating the caspase-3/gasdermin E (GSDME) pathway. These findings suggested that 12k is a promising drug candidate in cancer therapy and highlighted the potential of sulfoximines as a valuable functional group in drug discovery.

Low Bandgap 2D Perovskite Single Crystal with Anomalous-large Charges/ions Collection Ratio for Ultra-sensitive and Stable X-ray Detectors.

The low-dimensional halide perovskites have attracted increasing attention due to their improved moisture stability, reduced defects, and suppressed ions migration in many optoelectronic devices such as solar cells, light-emitting diodes, X-ray detectors, and so on. However, they are still limited by their large band gap and short charge carriers' diffusion length. Here, we demonstrate that the introduction of metal ions into organic interlayers of two-dimensional (2D) perovskite by cross-linking the copper paddle-wheel cluster-based lead bromide ([Cu(O2 C-(CH2 )3 -NH3 )2 ]PbBr4 ) perovskite single crystals with coordination bonds can not only significantly reduce the perovskite band gap to 0.96 eV to boost the X-ray induced charge carriers, but can also selectively improve the charge carriers' transport along the out-of-plane direction and blocking the ions motion paths. The [Cu(O2 C-(CH2 )3 -NH3 )2 ]PbBr4 single-crystal device can reach a record charges/ions collection ratio of 1.69×1018 ±4.7 % µGyair -1 s, and exhibit a large sensitivity of 1.14×105 ±7% µC Gyair -1 cm-2 with the lowest detectable dose rate of 56 nGyair s-1 under 120 keV X-rays irradiation. In addition, [Cu(O2 C-(CH2 )3 -NH3 )2 ]PbBr4 single-crystal detector exposed to the air without any encapsulation shows excellent X-ray imaging capability with long-term operational stability without any attenuation of 120 days.

Decomposition-Reassembly Synthesis of a Silverton-Type Polyoxometalate 3D Framework: Semiconducting Properties and Photocatalytic Applications.

Polyoxometalate-based all-inorganic three-dimensional (3D) frameworks have recently attracted attention as a unique class of materials due to their unique physicochemical properties and a wide field of application with excellent prospects. We herein synthesized a novel all-inorganic 3D framework material based on cobalt-substituted Silverton-type polyoxometalate, H6{Co6W10O42[Co(H2O)4]3}·2H2O (Co9W10), which was successfully constructed using Na12[WCo3II(H2O)2(CoIIW9O34)2]·46-48H2O (Co5W19) and Co(NO3)2·6H2O as starting materials in a hydrothermal reaction via a decomposition-reassembly route together with the rational adjustment of pH values. Co9W10 has been structurally characterized using single-crystal X-ray diffraction. Photocurrent response, band-gap (Eg) value, and the VB-XPS spectrum have been measured to reveal the semiconducting property of Co9W10. Furthermore, we synthesized x% PTh/Co9W10 composites (PTh = polythiophene, x = 0.5, 1, 2, 5) for photodegradation of tetracycline hydrochloride (TH) to evaluate the photocatalytic activities of title composites. Due to the optimal molar ratio of hybrids and matching energy levels, 2% PTh/Co9W10 composites show the best photocatalytic activities among these composites.

Exploring the Coordination Modes of a Keggin-Type [ZnW12O40]6- Anionic Cluster: Bonding Patterns, Crystal Structure, and Semiconducting Properties.

Polyoxometalate-based organic-inorganic hybrid compounds (POIHCs) have been greatly developed due to their wide application prospects, but the pursuit of their directed synthesis via molecular design still remains a challenge. Herein, we demonstrate that the coordination modes of the Keggin-type [ZnW12O40]6- anion can be tuned, which leads to different semiconductor characteristics. Using the same building block, ligand, and metal ion (ZnW12, phen, Cu2+), we synthesized three new POIHCs with different bonding patterns by means of different coordination modes of ZnW12. The three POIHCs (H2phen){ZnW12O40[Cu(phen)2]2}·3H2O (1), {ZnW12O40[Cu(phen)(H2O)2]2[Cu(phen)(H2O)]}n·3H2O (2), and (Me4N)2{ZnW12O40[Cu(phen)(H2O)]2}n·5H2O (3) (phen = 1,10-phenanthroline) have been structurally characterized by single-crystal X-ray diffraction. Compound 1 appears as a zero-dimensional coordination complex cluster, while compounds 2 and 3 are both 1D chain structures with different Cu2+ bridge linkages. Although these three POIHCs possess the same chemical components, their semiconductor properties are different, which is demonstrated by measurements of transient photocurrent and band gap (Eg) values. Furthermore, we carried out comparative experiments on the photoconductivity performance of compounds 1-3 and their photocatalytic reduction from O2 to H2O2, indicating the significant influence of the energy level matching on the photocatalytic activity.

Cancer Cell Membrane Vesicle for Multiplex MicroRNA Imaging in Living Cells.

Highly efficient cellular transfection and intracellular signal amplification is a prerequisite for low-abundant microRNA (miRNA) imaging and biomedical application. Herein, we report a functional cancer cell membrane (CM) vesicle, Au-P/DSN@CM (DSN, double-specific nucleases), which consists of Au nanoparticles modified with three types of fluorescent miRNA detection probes (Au-P) and DSN that simultaneously encapsulate in cancer CM. We find that the Au-P/DSN@CM could specifically target the cancer cell and transfect the cell with higher efficiency than Au nanoparticles. The internalized Au-P/DSN@CM could further specifically recognize the target miRNA and induce DSN-assisted target recycle signal amplification, leading to multiple miRNA simultaneous detection with high sensitivity. It successfully detects oncogenic miRNAs in MCF-7 cells with high sensitivity and is amenable to monitor the dynamic expression change of oncogenic miRNAs in cancer cells. Our study represents a promising gene delivery vector for cancer diagnosis and potential therapy.

Rationally Designing Metal-Organic Frameworks Based on [Ln2] Magnetic Building Blocks Utilizing 2-Hydroxyisophthalate and Fine-Tuning the Magnetic Properties of Dy Analogues by Terminal Coordinated Solvents.

By utilizing the 2-hydroxyisophthalic acid (H3ipO) ligand, 2D metal-organic frameworks (MOFs) featuring rare Ophenol-bridged [Ln2]-magnetic building blocks (MBBs), [Ln2(ipO)2(DMF)(H2O)] [Ln = Gd (1), Dy (2); DMF = N,N-dimethylformamide], were rationally designed and synthesized. When the reaction solvents that behave as terminal ligands were changed, the coordination geometries of LnIII ions and the arrangement fashion of [Ln2]-MBBs for these MOFs were modified accordingly. Another type of 2D MOF of [Ln2(ipO)2(H2O)4]·2H2O [Ln = Gd (3), Dy (4)] was thus obtained. MOFs 1 and 3 exhibited favorable magnetocaloric effect, whose maximum -ΔSm values reach 30.0 and 31.7 J kg-1 K-1, respectively. None of the single-molecule-magnet (SMM) behavior was observed in 2. However, from 2 to 4, the change of the terminal coordinated solvents brought obvious improvement of the magnetic properties. MOF 4 showed interesting relaxation behavior, in which dual relaxation was only visible under weak direct-current fields, and its highest effective energy barrier (Ueff) reached up to 243 K. Ab initio calculations revealed the tuning mechanism of the terminal coordinated solvents. Their change optimized the arrangements of the magnetic axis of the DyIII centers in both each MBB and the whole framework, thus improving the magnetic anisotropy and magnetic interactions of the system. Significantly, within the [Dy2]-MBBs of 4, the angle made by the individual magnetic axis and Dy···Dy' line is nearly 0°. This case favoring a high SMM performance not only was scarcely achieved in discrete {Ln2}-SMMs with numerous members but also has never been observed in any MBB-based MOFs as far as we know.

Online extraction and cleanup-quadrupole time-of-flight tandem mass spectrometry for rapid analysis of bioactive components in natural products.

The challenges in direct analysis of a complex system (e.g., natural product, food, biological samples) by mass spectrometry (MS) are the sophisticated sample preparation methods and ionization suppression by matrix interferences. Consequently, a novel online extraction and cleanup-quadrupole time-of-flight tandem mass spectrometry (OLEC-QTOF-MS/MS) system was developed for rapid, efficient, and sensitive analysis of flavonoids in Citri Reticulatae Pericarpium (CRP). For the OLEC strategy, a guard column packed with solid CRP (0.5 mg) and C18 gel was positioned on a manual injection valve, in which interferences with large polarities were online removed by methanol-0.1% formic acid (25:75, v/v) for 3 min, while target flavonoids were online extracted by methanol-0.1% formic acid (70:30, v/v) for 10 min for the subsequent QTOF-MS/MS analysis. The method was validated using official marker, hesperidin, by external standard method. Excellent linear ranges from 0.02 to 52.0 µg L-1 (R2, 0.9935) with a limit of detection (LOD) of 0.006 µg were obtained. Acceptable reproducibility (RSD 8.1 and 9.6% for intra- and inter-day variations) and recoveries (from 99.5 to 112.0%) were also attained. In addition, 20 flavonoids in CRP were identified according to their exact mass and fragmentation ions in MS/MS spectra, and five of them were reported for the first time. Obviously, OLEC-QTOF-MS/MS presented several advantages, such as simple operation and high sensitivity, which provided new perspectives for rapid analysis of bioactive components in complex natural products. Graphical Abstract ᅟ.

Direct from solid natural products to pure compounds in a single step: Coupling online extraction with high-speed counter-current chromatography.

Extraction is the most important step in the purification of bioactive compounds from natural products. This study introduces a simple online extraction strategy coupled with high-speed counter-current chromatography for efficient extraction and purification of bioactive components from solid natural products. For online extraction strategy, 1.0 g of ground Mangnolia officinalis or Piper nigrum was loaded into a guard column, which was then positioned on the manual injection valve instead of the sample loop. Bioactive components were directly extracted by the mobile phase of high-speed counter-current chromatography, and then transferred into high-speed counter-current chromatography for purification. In addition, the compatibility of the developed methodology for direct purification of bioactive components from fresh M. officinalis was successfully demonstrated. Obviously, in comparison with traditional offline heat-reflux extraction, online extraction avoided the instrument, time, solvent, and energy consumption, and purified two phenolic compounds (honokiol and magnolol) from M. officinalis and three alkaloids (piperyline, piperine, and piperanine) from P. nigrum with high extraction efficiency. The superiority of the developed methodology is to establish an easy, rapid, and efficient technique for the purification of a wide variety of bioactive components from solid natural products.

Arising 2D Perovskites for Ionizing Radiation Detection.

2D perovskites have greatly improved moisture stability owing to the large organic cations embedded in the inorganic octahedral structure, which also suppresses the ions migration and reduces the dark current. The suppression of ions migration by 2D perovskites effectively suppresses excessive device noise and baseline drift and shows excellent potential in the direct X-ray detection field. In addition, 2D perovskites have gradually emerged with many unique properties, such as anisotropy, tunable bandgap, high photoluminescence quantum yield, and wide range exciton binding energy, which continuously promote the development of 2D perovskites in ionizing radiation detection. This review aims to systematically summarize the advances and progress of 2D halide perovskite semiconductor and scintillator ionizing radiation detectors, including reported alpha (α) particle, beta (ß) particle, neutron, X-ray, and gamma (γ) ray detection. The unique structural features of 2D perovskites and their advantages in X-ray detection are discussed. Development directions are also proposed to overcome the limitations of 2D halide perovskite radiation detectors.

Cation-π interactions enabled water-stable perovskite X-ray flat mini-panel imager.

Sensitive and stable perovskite X-ray detectors are attractive in low-dosage medical examinations. The high sensitivity, tunable chemical compositions, electronic dimensions, and low-cost raw materials make perovskites promising next-generation semiconductors. However, their ionic nature brings serious concerns about their chemical and water stability, limiting their applications in well-established technologies like crystal polishing, micro-processing, photolithography, etc. Herein we report a one-dimensional tryptamine lead iodide perovskite, which is stable in water for several months as the strong cation-π interactions between organic cations. The one-dimensional and two-dimensional tryptamine lead iodide perovskite tablets are switchable through thermal-annealing or water-soaking treatments to relax microstrains. The water-stable and microstrain-free one-dimensional perovskite tablets yield a large sensitivity of 2.5 × 106 µC Gyair-1 cm-2 with the lowest detectable dose rate of 5 nGyair s-1. Microelectrode arrays are realized by surface photolithography to construct high-performance X-ray flat mini-panels with good X-ray imaging capability, and a record spatial resolution of 17.2 lp mm-1 is demonstrated.

Differential perovskite hemispherical photodetector for intelligent imaging and location tracking.

Advanced photodetectors with intelligent functions are expected to take an important role in future technology. However, completing complex detection tasks within a limited number of pixels is still challenging. Here, we report a differential perovskite hemispherical photodetector serving as a smart locator for intelligent imaging and location tracking. The high external quantum efficiency (~1000%) and low noise (10-13 A Hz-0.5) of perovskite hemispherical photodetector enable stable and large variations in signal response. Analysing the differential light response of only 8 pixels with the computer algorithm can realize the capability of colorful imaging and a computational spectral resolution of 4.7 nm in a low-cost and lensless device geometry. Through machine learning to mimic the differential current signal under different applied biases, one more dimensional detection information can be recorded, for dynamically tracking the running trajectory of an object in a three-dimensional space or two-dimensional plane with a color classification function.

Protective effect of Saussurea involucrata polysaccharide against skin dryness induced by ultraviolet radiation.

Background: Exposure to ultraviolet B (UVB) radiation can damage the epidermis barrier function and eventually result in skin dryness. At present, little work is being devoted to skin dryness. Searching for active ingredients that can protect the skin against UVB-induced dryness will have scientific significance. Methods: Saussurea involucrata polysaccharide (SIP) has been shown to have significant antioxidant and anti-photodamage effects on the skin following UVB irradiation. To evaluate the effect of SIP on UVB-induced skin dryness ex vivo, SIP-containing hydrogel was applied in a mouse model following exposure to UVB and the levels of histopathological changes, DNA damage, inflammation, keratinocyte differentiation, lipid content were then evaluated. The underlying mechanisms of SIP to protect the cells against UVB induced-dryness were determined in HaCaT cells. Results: SIP was found to lower UVB-induced oxidative stress and DNA damage while increasing keratinocyte differentiation and lipid production. Western blot analysis of UVB-irradiated skin tissue revealed a significant increase in peroxisome proliferator-activated receptor-α (PPAR-α) levels, indicating that the underlying mechanism may be related to PPAR-α signaling pathway activation. Conclusions: By activating the PPAR-α pathway, SIP could alleviate UVB-induced oxidative stress and inhibit the inflammatory response, regulate proliferation and differentiation of keratinocytes, and mitigate lipid synthesis disorder. These findings could provide candidate active ingredients with relatively clear mechanistic actions for the development of skin sunscreen moisturizers.

Prominent Free Charges Tunneling Through Organic Interlayer of 2D Perovskites.

The diversity of organic cations greatly enriches the species of 2D perovskites; traditional 2D Ruddlesden-Popper (RP) and Dion-Jacobson (DJ) perovskites are synthesized by two different organic amines. Here, according to the difference in pKa values between conjugated acids of monoprotonated and biprotonated 4-(2-Aminoethyl)pyridine (4AEPy) ions, the 2D perovskites of RP (4AEPy)2 PbI4 and DJ (4AEPy)PbI4 from same organic amine is reported, which can realize reversible transformation under the treatment of HI and NH3 , respectively. The interaction of N-H···N hydrogen bond between adjacent organic molecules in (4AEPy)2 PbI4 leads to the bending conformation of ethylamine groups, which results in a 2.4 Å reduction in layer spacing compared to typical phenylethylamine lead iodine ((PEA)2 PbI4 ) 2D perovskite. Besides, the ethylamine groups of organic layers in (4AEPy)PbI4 are deeply inserted into octahedral cavities and directly participate in the construction of the conduction band minimum, which leads to a small exciton binding energy of 27.3 meV to generate free charges. The stronger coupling between the organic and inorganic layers and the minor exciton binding energy can promote the DJ phase to possess a more stable structure and better optoelectronic properties. Thus the (4AEPy)PbI4 device displays better light response and X-ray detection capability with a high sensitivity of 5627 µC Gyair -1 cm-2 and the lowest detectable dose rate of 20 nGyair s-1 .

Peripheral Inflammatory Biomarkers of Alzheimer's Disease.

Alzheimer's disease (AD) is a neurodegenerative disease of unknown pathological origin. The clinical diagnosis of AD is time-consuming and needs to a combination of clinical evaluation, psychological testing, and imaging assessments. Biomarkers may be good indicators for the clinical diagnosis of AD; hence, it is important to identify suitable biomarkers for the diagnosis and treatment of AD. Peripheral inflammatory biomarkers have been the focus of research in recent years. This review summarizes the role of inflammatory biomarkers in the disease course of AD.

Cucurbitacin promotes hair growth in mice by inhibiting the expression of fibroblast growth factor 18.

Background: The inhibition of fibroblast growth factor 18 (FGF18) promotes the transition of hair follicles (HFs) from the telogen phase to the anagen phase. Cucurbitacin has been shown to have a good effect in promoting hair cell growth. This study explored the potential effect of cucurbitacin on hair growth and its effect on FGF18 expression in mice. Methods: Male C57BL/6J mice were randomly divided into the following two groups: (I) the vehicle group; and (II) the cucurbitacin group. Matrix cream and cucurbitacin cream were applied to the depilated skin on the back of the vehicle group mice and the cucurbitacin group mice, respectively. On days 3, 6, 9, 12, 15, and 18, the hair growth in the depilated dorsal skin of the mice was recorded with a digital camera and a HF detector, and the HF cycle status of the mice was observed by hematoxylin and eosin (H&E) staining. In addition, the level of FGF18 messenger ribonucleic acid (mRNA) in the dorsal skin was measured on days 15 and 18 by quantitative real-time polymerase chain reaction (qRT-PCR), while the level of FGF18 protein was measured by western blot and immunofluorescence staining. Results: The dorsal skin to which the cucurbitacin cream was applied began to darken on day 6 and grew hairs on day 9, which was 3 days earlier than the dorsal skin to which the matrix cream was applied. The H&E staining revealed a transition from the telogen phase to the anagen phase 3 days earlier for the cucurbitacin cream-treated skin than the matrix cream-treated skin. In addition, the skin treated with cucurbitacin cream also showed a significant decrease in FGF18 mRNA as seen by qRT-PCR, and reduced FGF18 protein levels as detected by western blot and immunofluorescence staining compared to the skin treated with matrix cream only. Conclusions: Cucurbitacin significantly reduced the levels of FGF18 mRNA and protein in the dorsal skin of mice to accelerate the HFs to enter the anagen phase earlier, thereby promoting the regeneration of hair. Thus, cucurbitacin can be considered a new and valuable agent for the development of anti-hair loss products.

Cryptotanshinone protects skin cells from ultraviolet radiation-induced photoaging via its antioxidant effect and by reducing mitochondrial dysfunction and inhibiting apoptosis.

The integrity of skin tissue structure and function plays an important role in maintaining skin rejuvenation. Ultraviolet (UV) radiation is the main environmental factor that causes skin aging through photodamage of the skin tissue. Cryptotanshinone (CTS), an active ingredient mianly derived from the Salvia plants of Lamiaceae, has many pharmacological effects, such as anti-inflammatory, antioxidant, and anti-tumor effects. In this study, we showed that CTS could ameliorate the photodamage induced by UV radiation in epidermal keratinocytes (HaCaT) and dermal fibroblasts (HFF-1) when applied to the cells before exposure to the radiation, effectively delaying the aging of the cells. CTS exerted its antiaging effect by reducing the level of reactive oxygen species (ROS) in the cells, attenuating DNA damage, activating the nuclear factor E2-related factor 2 (Nrf2) signaling pathway, and reduced mitochondrial dysfunction as well as inhibiting apoptosis. Further, CTS could promote mitochondrial biosynthesis in skin cells by activating the AMP-activated protein kinase (AMPK)/sirtuin-1 (SIRT1)/peroxisome proliferator-activated receptor-γ co-activator-1α (PGC-1α) signaling pathway. These findings demonstrated the protective effects of CTS against UV radiation-induced skin photoaging and provided a theoretical and experimental basis for the application of CTS as an anti-photodamage and anti-aging agent for the skin.

Associations of social jetlag and emotional and behavioral problems among Chinese preschoolers.

To describe the prevalence of social jetlag among preschoolers and explore its association with emotional and behavioral problems, we conducted a cross-sectional survey of healthy development among preschool children in 11 cities in October and November 2017. The study included 27 200 children aged 3-6 years and the questionnaires were completed exclusively by their parents or main caregivers. Social jetlag was calculated by difference of sleep midpoint between weekdays and weekends. Emotional and behavioral problems (emotional symptoms, conduct problems, hyperactivity, peer interaction, and prosocial behavior) among preschoolers were assessed by the Strengths and Difficulties Questionnaire (SDQ). The binary logistic regression model was used to examine the association between social jetlag and emotional/behavioral problems in preschool children. The social jetlag was 0.60 hours in boys and 0.64 hours in girls. After adjusting for confounding factors as children' s gender, age, only child, living area, family economic status, mother's age and education, father's education, screen time and full-day sleep time, we found that longer social jetlag (≥1 h/d) was positively associated with overall emotional and behavioral problems (OR = 1.20, 95%CI: 1.10-1.32; P < .001), emotional symptoms (OR = 1.23, 95% CI: 1.11-1.15, P < .001), hyperactivity (OR = 1.20, 95%CI: 1.11-1.30, P < .001) and conduct problems (OR = 1.18, 95%CI: 1.07-1.31, P < .01). We found that social jetlag is prevalent among Chinese preschool children and is positively associated with emotional and behavioral problems.

Expedite Fluorescent Sensor Prototype for Hydrogen Peroxide Detection with Long-Life Test Substrates.

We report a practical fluorescent sensor device for the trace amount detection of hydrogen peroxide vapor. In this paper, we have significantly improved the performance of fluorescence analysis for the detection of peroxides by solving the problems of packaging and storage of active materials and transferring the chemical experiment phenomenon to the actual project output. The fluorescent sensor molecule, test substrates, mixing methods, and the way to improve the life time are carefully studied. Combined with the design of circuit and programming, a field-test prototype was designed for peroxide explosives and its performance and algorithm were screened and optimized. In the detection of traces of H2O2 generated by ultraviolet separation or leaked as inherent impurities, the high-efficiency and rapid detection of peroxide-based explosives is achieved. The detection limit of H2O2 is expected to reach 2 ppb, and the response time can reach <0.5 s.

Suppression of FGF5 and FGF18 Expression by Cholesterol-Modified siRNAs Promotes Hair Growth in Mice.

FGF5 and FGF18 are key factors in the regulation of the hair follicle cycle. FGF5 is overexpressed during the late anagen phase and serves as a crucial regulatory factor that promotes the anagen-to-catagen transition in the hair follicle cycle. FGF18, which is overexpressed during the telogen phase, mainly regulates the hair follicle cycle by maintaining the telogen phase and inhibiting the entry of hair follicles into the anagen phase. The inhibition of FGF5 may prolong the anagen phase, whereas the inhibition of FGF18 may promote the transition of the hair follicles from the telogen phase to the anagen phase. In the present study, we used siRNA to suppress FGF5 or FGF18 expression as a way to inhibit the activity of these genes. Using qPCR, we showed that FGF5-targeting siRNA modified by cholesterol was more effective than the same siRNA bound to a cell-penetrating peptide at suppressing the expression of FGF5 both in vitro and in vivo. We then investigated the effects of the cholesterol-modified siRNA targeting either FGF5 or FGF18 on the hair follicle cycle in a depilated area of the skin on the back of mice. The cholesterol-modified siRNA, delivered by intradermal injection, effectively regulated the hair follicle cycle by inhibiting the expression of FGF5 and FGF18. More specifically, intradermal injection of a cholesterol-modified FGF5-targeted siRNA effectively prolonged the anagen phase of the hair follicles, whereas intradermal injection of the cholesterol-modified FGF18-targeted siRNA led to the mobilization of telogen follicles to enter the anagen phase earlier. The inhibitory effect of the cholesterol-modified FGF18-targeted siRNA on FGF18 expression was also evaluated for a topically applied siRNA. Topical application of a cream containing the cholesterol-modified FGF18-targeted siRNA on a depilated area of the skin of the back of mice revealed comparable inhibition of FGF18 expression with that observed for the same siRNA delivered by intradermal injection. These findings suggested that alopecia could be prevented and hair regrowth could be restored either through the intradermal injection of cholesterol-modified siRNA targeting FGF5 or FGF18 or the topical application of FGF18 siRNA.