A Flexible MXene-Black Phosphorus/Zinc Oxide Hybrid Structure with Excellent UVA-Specific Photoelectric Sensing Properties for Human Skin Protection.

Ultraviolet A (UVA) radiation causes various irreversible damages to human skin, so the research about UVA-specific sensing device is urgent. 2D black phosphorus (BP) is used in many photosensors due to its advantages of high carrier mobility and tunable bandgap, but its application for UVA-specific photosensor is not reported. Here, a MXene-BP/Zinc oxide (ZnO) hybrid structure with lamellar-spherical interfaces like finger lime fruit is prepared by the layer-by-layer assembly (LLA) method, and p-n junctions are constructed between BP and ZnO with the Ti3C2Tx electrode, showing excellent photoelectric performance. Density functional theory (DFT) calculations demonstrate that the enhanced performance is attributed to the rapid separation of photogenerated carriers in the presence of a built-in electric field at interface. Furthermore, a flexible MXene-BP/ZnO based UVA-specific photosensor is prepared, which shows a specific response to UVA as high as 7 mA W-1 and excellent mechanical stability, maintaining 98.46% response after 100 bending cycles. In particular, the integrated anti-UVA skin protection device shows excellent UVA-specific identification and wireless transmission capability, which can provide timely UVA exposure information and skin protection warning for the visually impaired. This work demonstrates a new approach for further developments of advanced photoelectric sensing technology toward improving people's skin health protection.

GIWAXS experimental methods at the NFPS-BL17B beamline at Shanghai Synchrotron Radiation Facility.

The BL17B beamline at the Shanghai Synchrotron Radiation Facility was first designed as a versatile high-throughput protein crystallography beamline and one of five beamlines affiliated to the National Facility for Protein Science in Shanghai. It was officially opened to users in July 2015. As a bending magnet beamline, BL17B has the advantages of high photon flux, brightness, energy resolution and continuous adjustable energy between 5 and 23 keV. The experimental station excels in crystal screening and structure determination, providing cost-effective routine experimental services to numerous users. Given the interdisciplinary and green energy research demands, BL17B beamline has undergone optimization, expanded its range of experimental methods and enhanced sample environments for a more user-friendly testing mode. These methods include single-crystal X-ray diffraction, powder crystal X-ray diffraction, wide-angle X-ray scattering, grazing-incidence wide-angle X-ray scattering (GIWAXS), and fully scattered atom pair distribution function analysis, covering structure detection from crystalline to amorphous states. This paper primarily presents the performance of the BL17B beamline and the application of the GIWAXS methodology at the beamline in the field of perovskite materials.

The inactivation of the non-enveloped enterovirus 71 (EV71) by a novel disinfectant gel formulation for topical use.

BACKGROUND: Hand-foot-mouth disease may cause severe central nervous system complications and even death, that is induced mainly by enterovirus 71 (EV71), which is a non-enveloped virus. Inactivation of the EV71 on hands could effectively inhibit the transmission. However, the inactivations of the EV71 by conventional disinfectants including the alcohols are poor, due to the high stability of the EV71. A novel pyridyl imidazolidinone compound (TJAB1099) was designed to specifically inhibit EV71 replication in vitro. It may potentially be developed as formulations applied on hands for EV71 transmission control. METHODS: The stress stability of TJAB1099 was first evaluated after storing in high temperature (60 °C, RH 10%), high humidity (25 °C, RH90%), and the high-intensity photolysis (4500 Lx ± 500 Lx) for 15 days, respectively. A wash-free antimicrobial gel containing the TJAB1099 was developed using the copolymer carrier. The antiviral activity, the acute oral toxicity, and the local irritation of the antimicrobial gel were evaluated accordingly. RESULTS: The results indicated that the TJAB1099 was stable during the storage in high temperature and humidity. However, a significant change (p < .0001) was detected when TJAB1099 stored in the high-intensity photolysis. The antimicrobial gel containing 1 µM TJAB1099 could inhibit EV71 significantly higher than the ethanol (75%) (p < .0001) and commercialized disinfectant products (p < .0001). The results of acute oral toxicity and the local irritation suggest that the TJAB1099 containing antimicrobial gel was not causing skin irritations and acute oral toxicity symptoms. CONCLUSIONS: The results suggest that the antimicrobial gel containing TJAB1099 was safe and could effectively inhibit EV71 transmission in vitro.

Determination of triazine herbicides in fresh vegetables by dynamic microwave-assisted extraction coupled with homogeneous ionic liquid microextraction high performance liquid chromatography.

A novel extraction method, dynamic microwave-assisted extraction coupled with homogeneous ionic liquid microextraction, was developed for the determination of triazine herbicides, including desmetryn, terbumeton, propazine, terbuthylazine, dimethametryn, and dipropetryn in fresh vegetable samples by high performance liquid chromatography (HPLC). In the developed method, 120 µL of 1-butyl-3-methylimidazolium tetrafluoroborate ([C4MIM][BF4]) was added to 10 mL of aqueous solution containing 0.3 g of NaCl to obtained the extraction solvent. Six triazines could be extracted completely within 4 min by the present method. Then, [NH4][PF6] was added into the extract to form a water-insoluble ionic liquid [C4MIM][PF6] via a simple metathesis reaction, and the analytes were enriched into the ionic liquid phase. After centrifugation and dilution with acetonitrile, the resulting solution was analyzed directly by HPLC. The effects of some experimental parameters, including type and volume of ionic liquid, volume of extraction solvent, amount of ion-pairing agent [NH4][PF6], salt concentration, microwave power, and flow rate of extraction solvent on the extraction efficiency were investigated and optimized. Under the optimum experimental conditions, the linearity for determining the analytes was in the range of 2.50-250.00 µg kg(-1), with the correlation coefficients ranging from 0.9989 to 0.9999. When the present method was applied to the analysis of vegetable samples, satisfactory recoveries were obtained in the range of 76.8%-106.9%, and relative standard deviations were lower than 9.8%.

Sonochemical regulation of oxygen vacancies for Bi2WO6 nanosheet-based photoanodes to promote photoelectrochemical performance.

Integration of oxygen vacancies (Vo) into nanostructured semiconductor-based photocatalysts has been recognized as a promising strategy for enhancing the performance of photoelectrochemical (PEC) water splitting. However, precisely controlling the Vo concentration in photocatalysts via an effective and tunable approach remains challenging. Herein, a series of optimized bismuth tungstate (Bi2WO6) nanosheet-based photoanodes with varying concentrations of Vo were prepared by a sonochemical method with in situ cavitation detection, which enables accurate manipulation of the acoustic cavitation intensity applied to the surface of Bi2WO6 photoanodes in alkaline solution. Based on the analysis of the Vo concentration and sound field characteristics, the mechanism of sonochemical regulation of Vo in Bi2WO6 nanosheets was interpreted. Specifically, the increase in Vo concentration can be attributed to the enhancement of Bi-O bond dissociation. This enhancement is influenced not only by the intensified impact of shear force and the generation of active radicals by transient cavitation, but also by the accelerated diffusion of the reactant, a result of stable cavitation. By optimizing the transient and stable cavitation intensity, a Vo-rich Bi2WO6 photoanode was obtained without altering the microstructure of Bi2WO6 nanosheets. The presence of high concentration Vo facilitates the interfacial chemical reactivity and the transmission of photogenerated carriers, leading to the drastic promotion of the PEC water splitting performance. The transient photocurrent density of the Vo-rich Bi2WO6 photoanode reaches 69.2 µA cm-2 (1.23 V vs. RHE), 7.86 times that of the untreated Bi2WO6 photoanode. Additionally, the charge injection efficiency increases to 35.4%. This work provides a controllable and effective method for defect engineering of nanostructured semiconductor-based electrodes.

Upgrade of crystallography beamline BL19U1 at the Shanghai Synchrotron Radiation Facility.

BL19U1, an energy-tunable protein complex crystallography beamline at the Shanghai Synchrotron Radiation Facility, has emerged as one of the most productive MX beamlines since opening to the public in July 2015. As of October 2023, it has contributed to over 2000 protein structures deposited in the Protein Data Bank (PDB), resulting in the publication of more than 1000 scientific papers. In response to increasing interest in structure-based drug design utilizing X-ray crystallography for fragment library screening, enhancements have been implemented in both hardware and data collection systems on the beamline to optimize efficiency. Hardware upgrades include the transition from MD2 to MD2S for the diffractometer, alongside the installation of a humidity controller featuring a rapid nozzle exchanger. This allows users to opt for either low-temperature or room-temperature data collection modes. The control system has been upgraded from Blu-Ice to MXCuBE3, which supports website-mode data collection, providing enhanced compatibility and easy expansion with new features. An automated data processing pipeline has also been developed to offer users real-time feedback on data quality.

Ionic liquid-based microwave-assisted surfactant-improved dispersive liquid-liquid microextraction and derivatization of aminoglycosides in milk samples.

A green and simple method, ionic liquid-based microwave-assisted surfactant-improved dispersive liquid-liquid microextraction and derivatization was developed for the determination of aminoglycosides in milk samples. Nonionic surfactant Triton X-100 and ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate were used as the disperser and extraction solvent, respectively. Extraction, preconcentration, and derivatization of aminoglycosides were carried out in a single step. Several experimental parameters, including type and volume of extraction solvent, type and concentration of surfactant, microwave power and irradiation time, concentration of derivatization reagent, and pH value and volume of buffer were investigated and optimized. Under the optimum experimental conditions, the linearities for determining the analytes were in the range 0.4-10.0 ng/mL for tobramycin, 1.0-25.0 ng/mL for neomycin, and 2.0-50.0 ng/mL for gentamicin, with the correlation coefficients ranging from 0.9991 to 0.9998. The LODs for the analytes were between 0.11 and 0.50 ng/mL. The present method was applied to the analysis of different milk samples, and the recoveries of aminoglycosides obtained were in the range 96.4-105.4% with the RSDs lower than 5.5%. The results showed that the present method was a rapid, convenient, and environmentally friendly method for the determination of aminoglycosides in milk samples.

Tailored novel multifunctional benzyl-functionalized magnetic ionic liquid for rapid and efficient monitoring of trace fluoroquinolones in food samples.

The novel hydrophobic cobalt anion-based benzyl-functionalized magnetic ionic liquid (MIL) was first designed, synthesized, and employed as a multifunctional extractant (for extraction, visual observation, and magnetic separation) for fast dispersive liquid-liquid microextraction of fluoroquinolones (FQs). According to the aromatic structure of FQs, three benzyl-functionalized MILs were customized by introducing various aromatic functional groups (benzyl, paracetyl phenyl, and m-methoxyphenyl) to justify the extraction efficiency and selectivity. In particular, the paracetyl phenyl functionalized MIL showed superior extraction efficiency among others due to its hydrophobicity and strong interactions of hydrogen bonding and π-π stacking. Moreover, under optimal conditions, the limits of detection were as low as 0.47-0.56 µg/L, and the enhancement factors were as high as 88-95. The recoveries were between 90.8 % and 107.8 %, and the relative standard deviation was less than 5.4 %. Ascribed to these outstanding experimental results, the benzyl-functionalized MIL is a potential magnetic extractant for detecting trace FQs in food samples.

Application of supramolecular solvent based on the surface-active ionic liquid in dispersive liquid-liquid microextraction of triazine herbicides in tea samples.

In this study, a novel supramolecular solvent based on surface-active ionic liquid was prepared and used as an extraction solvent for dispersive liquid-liquid microextraction of four triazine herbicides in tea samples. The formation mechanism, microstructure and physicochemical properties of supramolecular solvent were studied. Some parameters, including the molar ratio of surface-active ionic liquid to tetrahydrofuran, volume of supramolecular solvent, vortex time, pH of sample solution, type and amount of salt, were investigated and optimized. The good linearities (r > 0.9990) for the analytes were obtained. The limits of detection and quantification for triazine herbicides were in the range of 1.7-2.1 µg kg-1 and 5.6-7.1 µg kg-1, respectively. The spiked recoveries were 80.0-119.9 %. The supramolecular solvent prepared in this study has the advantages of simple preparation process, low viscosity and good dispersibility. It can be used for the extraction and enrichment of trace triazine herbicides in tea samples.

Ionic liquid-based carbon dots as highly biocompatible and sensitive fluorescent probe for the determination of vitamin P in fruit samples.

Vitamin P (VP) known as rutin is one of the common flavonoids, which widely exists in fruits and vegetables and often used as a dietary additive. The rapid and accurate detection of VP in food matrices is critical for evaluating food quality and guiding diet. Herein, a rapid, accurate, and selective detection scheme for VP in fruit samples was proposed for the first time using ionic liquid-based carbon dots (IL-CDs). The synthesized IL-CDs exhibited great biocompatibility and excellent optical properties including high fluorescence intensity, high quantum yield, and good fluorescence stability. Through an internal filtering effect (IFE), VP could greatly reduce the fluorescence of these CDs. In the present study, this probe demonstrated good sensitivity and excellent selectivity toward VP with a low detection limit of 60.0 nmol/L. Moreover, this approach was effectively applied to detect VP in food samples with a recovery range of 97 % to 119 %. More interestingly, the results of cell imaging suggested that IL-CDs were expected to be promising material for bioimaging.

Determination of sulfonamides in livers using matrix solid-phase dispersion extraction high-performance liquid chromatography.

The matrix solid-phase dispersion (MSPD) was applied for extracting seven sulfonamides (SAs) in liver samples. The separation and determination were carried out by high-performance liquid chromatography. The analytes were derivated with fluorescamine and detected with fluorescence detector. The types of dispersion adsorbents for MSPD were examined and the highest recovery was obtained when the diatomaceous earth was used as the dispersion adsorbent and the mass ratio of dispersion adsorbent to sample was 3:1. The acetone was used as the elution solvent. Under the optimal conditions, the linear range for determining the SAs in liver samples was 5.0-1000.0 ng/g. The porcine, chicken and cattle liver samples were analyzed and the average recoveries of seven SAs were higher than 84.6%.

One-pot synthesized organosilica nanospheres for multiplexed fluorescent nanobarcoding and subcellular tracking.

Multicolor microbeads are widely used in flow cytometry for various cellular and immunoassays. However, they are limited by their large size of around one to tens of micrometers. Nanomaterials for multiplexed analysis are emerging as valuable tools in high-throughput assays and fluorescence cell barcoding. We present barcoding and related cellular studies based on mass-produced organosilane-derived multifunctional nanospheres with a uniform size. Functional groups including thiols, amines, and azides were integrated in one step from various organosilanes without additional orthosilicates. Fluorescent nanobarcodes (NBs) were achieved through flexible physical adsorption and chemical ligation of spectrally separated fluorescent dyes. Live cells labeled with the NBs were readily distinguished by flow cytometry. The NBs have a small and uniform size (ca. 27 nm in diameter), excellent biocompatibility, rapid cellular uptake, and low dye leakage. The fluorescent nanospheres were applied for long-term cell tracking during multiple rounds of cell division and monitored over 48 hours. While most nanospheres were endolysosome-targeting, modification with fluorescein isothiocyanate (FITC) surprisingly lighted up the cell nucleus. This work lays the foundation of a unique family of functional nanomaterials promising for multiplex detection and other chemical and biological applications.

Microwave-accelerated derivatization prior to GC-MS determination of sex hormones.

A new microwave-accelerated derivatization method was developed for rapid determination of 13 natural sex hormones in feeds. Sex hormones were isolated from the sample matrix by ultrasonic extraction, followed by solid-phase extraction, derivatized under microwave irradiation, and then analyzed directly by gas chromatography-mass spectrometry (GC-MS) in selective ion monitoring (SIM) mode. The key parameters affecting derivatization efficiency, including microwave irradiation time, microwave power, and reaction solvent were studied. Under microwave power of 360 W and microwave irradiation for 3 min, 13 natural sex hormones were simultaneously derivatized using heptafluorobutyric acid anhydride (HFBA) as derivatization reagent. This method was applied to the determination of 13 natural sex hormones in different feed samples, and the obtained results were compared with those obtained by the traditional thermal derivatization. The recoveries from 58.1 to 111% were obtained at sex hormone concentrations of 10-300 µg/kg with RSDs ≤12.0%. The results showed that the proposed method was fast, simple, efficient and can be applied to the determination of 13 natural sex hormones in different feed samples.

Determination of sudan dyes in red wine and fruit juice using ionic liquid-based liquid-liquid microextraction and high-performance liquid chromatography.

The liquid-liquid microextraction (LLME) was developed for extracting sudan dyes from red wine and fruit juice. Room temperature ionic liquid was used as the extraction solvent. The target analytes were determined by high-performance liquid chromatography. The extraction parameters were optimized. The optimal conditions are as follows: volume of [C(6)MIM][PF(6)] 50 µL; the extraction time 10 min; pH value of the sample solution 7.0; NaCl concentration in sample solution 5%. The extraction recoveries for the analytes in red wine and fruit samples are 86.79-108.28 and 68.54-85.66%, whereas RSDs are 1.42-5.12 and 1.43-6.19%, respectively. The limits of detection and quantification were 0.428 and 1.426 ng/mL for sudan I, 0.938 and 3.127 ng/mL for sudan II, 1.334 and 4.445 ng/mL for sudan III, 1.454 and 4.846 ng/mL for sudan IV, respectively. Compared with conventional liquid-liquid extraction (CLLE) and ultrasonic extraction (UE), when LLME was applied, the sample amount was less (LLME: 4 mL; CLLE: 10 mL; UE: 10 mL), the extraction time was shorter (LLME: 15 min; CLLE: 110 min; UE: 50 min) and the extraction solvent amount was less (LLME: 0.05 mL IL; CLLE: 15 mL hexane; UE: 20 mL hexane). The proposed method offers a simple, rapid and efficient sample preparation for determining sudan dyes in red wine and fruit juice samples.

Headspace single drop microextraction coupled with microwave extraction of essential oil from plant materials.

Headspace single drop microextraction (HS-SDME) coupled with microwave extraction (ME) was developed and applied to the extraction of the essential oil from dried Syzygium aromaticum (L.) Merr. et Perry and Cuminum cyminum L. The operational parameters, such as microdrop volume, microwave absorption medium (MAM), extraction time, and microwave power were optimized. Ten microliters of decane was used as the microextraction solvent. Ionic liquid and carbonyl iron powder were used as MAM. The extraction time was less than 7 min at the microwave power of 440 W. The proposed method was compared with hydrodistillation (HD). There were no obvious differences in the constituents of essential oils obtained by the two methods.

Hydrogel-Based Optical Ion Sensors: Principles and Challenges for Point-of-Care Testing and Environmental Monitoring.

Hydrogel is a unique family of biocompatible materials with growing applications in chemical and biological sensors. During the past few decades, various hydrogel-based optical ion sensors have been developed aiming at point-of-care testing and environmental monitoring. In this Perspective, we provide an overview of the research field including topics such as photonic crystals, DNAzyme cross-linked hydrogels, ionophore-based ion sensing hydrogels, and fluoroionophore-based optodes. As the different sensing principles are summarized, each strategy offers its advantages and limitations. In a nutshell, developing optical ion sensing hydrogels is still in the early stage with many opportunities lying ahead, especially with challenges in selectivity, assay time, detection limit, and usability.

Colorimetric and fluorescent turn-on detection of chloride ions with ionophore and BODIPY: Evaluation with nanospheres and cellulose paper.

Here, we present the optical detection of chloride ions with co-extraction based anion-selective optodes containing a BODIPY derivative (BDP-OH) and the ionophore In(OEP)Cl. Spectroscopic studies suggested that BDP-OH and In(OEP)Cl formed an adduct BDP-O-In(OEP), which was converted to BDP-OH and In(OEP)Cl upon increasing sample Cl- concentration, and induced signal changes in both fluorescence and absorbance modes. The method was evaluated in polystyrene-graft-poly(ethylene oxide) (PS-PEO) nanospheres (ca. 40 nm in diameter) and on cellulose paper. In contrast to Cl- probes based on fluorescence quenching, the nanospheres exhibited turn-on fluorescence and ratiometric absorbance responses to a tunable Cl- concentration range (10 µM-1 M). Through fluorescence microscopy, the nanospheres were able to respond to Cl- concentration changes in HeLa cells. Cellulose paper-based Cl- optodes with colorimetric response were successfully used to measure Cl- in artificial sweat, providing a potential analytical tool for clinical diagnosis of cystic fibrosis.

Flexible Self-Powered Integrated Sensing System with 3D Periodic Ordered Black Phosphorus@MXene Thin-Films.

Accurate and continuous detection of physiological signals without the need for an external power supply is a key technology for realizing wearable electronics as next-generation biomedical devices. Herein, it is shown that a MXene/black phosphorus (BP)-based self-powered smart sensor system can be designed by integrating a flexible pressure sensor with direct-laser-writing micro-supercapacitors and solar cells. Using a layer-by-layer (LbL) self-assembly process to form a periodic interleaving MXene/BP lamellar structure results in a high energy-storage capacity in a direct-laser-writing micro-supercapacitor to drive the operation of sensors and compensate the intermittency of light illumination. Meanwhile, with MXene/BP as the sensitive layer in a flexible pressure sensor, the pressure sensitivity of the device can be improved to 77.61 kPa-1 at an optimized elastic modulus of 0.45 MPa. Furthermore, the smart sensor system with fast response time (10.9 ms) shows a real-time detection capability for the state of the human heart under physiological conditions. It is believed that the proposed study based on the design and integration of MXene materials will provide a general platform for next-generation self-powered electronics.

Microwave extraction of essential oils from dried fruits of Illicium verum Hook. f. and Cuminum cyminum L. using ionic liquid as the microwave absorption medium.

Ionic liquid was used as microwave absorption medium and applied to the extraction of essential oils from dried fruits of the Illicium verum Hook. f. and Cuminum cyminum L. by microwave-assisted extraction. The extraction time is less than 15 min at the microwave power of 440 W. The constituents of essential oils obtained by the proposed method were compared with those obtained by hydrodistillation. There is no obvious difference in the constituents of essential oils obtained by the two methods.

Matrix solid-phase dispersion extraction of sulfonamides from blood.

Matrix solid-phase dispersion extraction was applied to the extraction of sulfadiazine, sulfamerazine, and sulfamethazine from human and animal bloods. The separation and determination of the analytes were carried out by high-performance liquid chromatography. The effects of the types of the dispersion adsorbents and elution solvents were investigated, and the highest recovery was obtained when diatomaceous earth was used as the dispersion adsorbent, while acetone was used as the elution solvent. Under the optimal conditions, the linear range for determining the sulfonamides in blood samples was 0.020-10.0 µg/mL, and the average recoveries of the three sulfonamides were higher than 87.5%.