Direct Observation of Photon Induced Giant Band Renormalization in 2D PdSe2 Dichalcogenide by Transient Absorption Spectroscopy.

Insight into fundamental light-matter interaction as well as underlying photo-physical processes is crucial for the development of novel optoelectronic devices. Palladium diselenide (PdSe2 ), an important representative of emerging 2D noble metal dichalcogenides, has gain considerable attention owing to its unique optical, physical, and chemical properties. In this study, 2D PdSe2 nanosheets (NSs) are prepared using the liquid-phase exfoliation method. A broadband carrier relaxation dynamics from visible to near-infrared bands are revealed using a time-resolved transient absorption spectrometer, giving results that indicate band filling and bandgap renormalization (BGR) effects in the 2D PdSe2 NSs. The observed blue-shift of the transient absorption spectra at the primary stage and the subsequent red-shift can be ascribed to this BGR effect. These findings reveal the many-body character of the 2D TMDs material and may hold keys for applications in the field of optoelectronics and ultrafast photonics.

Crystallization-driven Nanoparticle Crystalsomes.

Nanoparticle (NP) assembly has been extensively studied, and a library of NP superstructures has been synthesized. These intricate structures show unique collective optical, electronic, and magnetic properties. In this work, we report a bottom-up approach for fabricating spherical gold nanoparticle (AuNP) assemblies that mimic colloidosomes. Co-crystallization of lipoic acid-end-functionalized poly(ethylene oxide) (PEO) and AuNPs in solution via a self-seeding method led to the formation of hollow spherical NP assemblies named nanoparticle crystalsomes (NPCs). Due to the spherical shape, the translational symmetry of PEO crystals is broken in NPCs, which can be attributed to the competition between NP close packing and polymer crystallization. This was confirmed by tuning the NPC morphology via varying the self-seeding temperature, crystallization temperature, and PEO molecular weight. We envisage that this strategy paves the way to attaining exquisite morphological control of NP assemblies with broken translational symmetry.

Ti3CN MXene-based ultra-sensitive optical fiber salinity sensor.

A Ti3CN MXene enabled ultra-sensitive optical fiber sensor is proposed, and a salinity measurement is conducted to evaluate its sensing performance in a low-concentration target molecule detection environment. Owing to the abundance of hydrophilic functional groups (-O, -F, and -OH), large specific surface, and broad-spectrum absorption characteristics of the MXene layers, the sensing performance of the MXene-incorporated sensor is greatly improved and an ultra-high salinity sensitivity of -5.34 nm/‰ is achieved (equivalent to a refractive index sensitivity of -33429 nm/RIU). Such an excellent sensing performance is 137.33% higher than that of the bare fiber sensor and is significantly enhanced over previously reported fiber sensors. Furthermore, the sensing performance of the sensor is improved without damaging the fiber structure, which is a huge advantage when compared with the traditional fiber post-processing techniques. Finally, because the refractive index is commonly used to characterize the detection ability of biosensors, our contribution suggests the integration of MXene as a potential approach to develop high-performance optical fiber biosensors.

How the Dark Triad associated with internet gaming disorder? The serial mediation of basic psychological needs satisfaction and negative coping styles.

According to the I-PACE model, this study focused on the role of need satisfaction and negative coping styles in the relationship between the Dark Triad (i.e., Machiavellianism, psychopathy, and narcissism) and internet gaming disorder (IGD). In a sample of 749 emerging adult gamers, a multiple mediation model with Dark Triad as the distal variable, psychological need satisfaction and negative coping style as mediating variables, and IGD as the outcome variable was tested. Results indicated that Machiavellianism and psychopathy were found to be significant predictors of IGD when mediated by psychological need satisfaction and negative coping styles. Narcissism predicts IGD only through the indirect effect of negative coping styles. The findings enhanced our understanding that Machiavellianism and psychopathy are characterized by compensatory use of internet games, as well as added new perspectives to the understanding of addiction mechanisms in narcissists.

A Facile Approach for Elemental-Doped Carbon Quantum Dots and Their Application for Efficient Photodetectors.

The present work demonstrates a facile hydrothermal approach to synthesize lanthanide-doped carbon quantum dots (CQDs) with europium and/or gadolinium elements. Taking the advantage of broadband adsorption in the ultraviolet-visible region, the doped QDs are directly used as building blocks for photo-electrochemical (PEC)-type photodetectors (PDs) and their performance is systematically investigated under various conditions. The europium (Eu) and gadolinium (Gd) co-doped (C:EuGd) QDs exhibit better photo-response than the single-elemental doped ones and also show outstanding long-term stability. According to the apparent response to light from 350 to 400 nm, the C:EuGd QDs are demonstrated to hold great potential for narrow-band PDs. This work highlights the practical applications of lanthanide-doped CQDs for PDs, and the results are beneficial for the development of elemental-doped CQDs in general.

Ultra-Small 2D PbS Nanoplatelets: Liquid-Phase Exfoliation and Emerging Applications for Photo-Electrochemical Photodetectors.

2D PbS nanoplatelets (NPLs) form an emerging class of photoactive materials and have been proposed as robust materials for high-performance optoelectronic devices. However, the main drawback of PbS NPLs is the large lateral size, which inhibits their further investigations and practical applications. In this work, ultra-small 2D PbS NPLs with uniform lateral size (11.2 ± 1.7 nm) and thickness (3.7 ± 0.9 nm, ≈6 layers) have been successfully fabricated by a facile liquid-phase exfoliation approach. Their transient optical response and photo-response behavior are evaluated by femtosecond-resolved transient absorption and photo-electrochemical (PEC) measurements. It is shown that the NPLs-based photodetectors (PDs) exhibit excellent photo-response performance from UV to the visible range, showing extremely high photo-responsivity (27.81 mA W-1 ) and remarkable detectivity (3.96 × 1010 Jones), which are figures of merit outperforming currently reported PEC-type PDs. The outstanding properties are further analyzed based on the results of first-principle calculations, including electronic band structure and free energies for the oxygen evolution reaction process. This work highlights promising applications of ultra-small 2D PbS NPLs with the potential for breakthrough developments also in other fields of optoelectronic devices.

Broadband Nonlinear Photonics in Few-Layer Borophene.

In this paper, 2D borophene is synthesized through a liquid-phase exfoliation. The morphology and structure of as-prepared borophene are systemically analyzed, and the Z-scan is used to measure the nonlinear optical properties. It is found that the saturable absorber (SA) properties of borophene make it serve as an excellent broadband optical switch, which is strongly used for mode-locking in near- and mid-infrared laser systems. Ultrastable pulses with durations as short as 792 and 693 fs are successfully delivered at the central wavelengths of 1063 and 1560 nm, respectively. Furthermore, stable pulses at a wavelength of 1878 nm are demonstrated from a thulium mode-locked fiber laser based on the same borophene SA. This research reveals a significant potential for borophene used in lasers helping extending the frontiers of photonic technologies.

Sulfur-Doped CoO Nanoflakes with Loosely Packed Structure Realizing Enhanced Oxygen Evolution Reaction.

The development of active and inexpensive electrocatalysts for the oxygen evolution reaction (OER) to promote water splitting has always been a major challenge. Cobalt-based oxides and sulfides have been actively investigated due to their low cost and high activity. However, the lower intrinsic conductivity of cobalt oxide and the inferior stability of cobalt sulfides still limit their practical application. Herein, CoO was chosen for a proof-of-concept study in which the anion-doping strategy was used to obtain an excellent catalyst. Sulfur incorporation optimizes the charge-transfer properties and active sites of sulfur-doped CoO (S-CoO) and thus gives rise to improved catalytic activity. Besides sulfur doping, the stable framework of the cobalt oxide was well maintained, and thus high stability of S-CoO throughout the reaction process was ensured.

Shackling Effect Induced Property Differences in Metallo-Supramolecular Polymers.

We demonstrate here the synthesis of a novel class of metallo-supramolecular polymers with shackled structure, via the coordination of cyclic di(bis-terpyridine-triphenyl ether ester) ligands with ruthenium(II) ions. The constraint from the ring topology via the shackling of ligands provides novel properties to these metallo-supramolecular polymers, including the formation of dendritic crystals, red-shift of absorption bands in the UV-vis spectra from interchain charge-transfer transitions, and a typical flash-type memory behavior.

Highly Chemiluminescent Magnetic Beads for Label-Free Sensing of 2,4,6-Trinitrotoluene.

Until now, despite the great success acquired in scientific research and commercial applications, magnetic beads (MBs) have been used for nothing more than a carrier in most cases in bioassays. In this work, highly chemiluminescent magnetic beads containing N-(4-aminobutyl)-N-ethyl isoluminol (ABEI) and Co2+ (Co2+/ABEI/MBs) were first synthesized via a facile strategy. ABEI and Co2+ were grafted onto the surface of carboxylated MBs by virtue of a carboxyl group and electrostatic interaction. The as-prepared Co2+/ABEI/MBs exhibited good paramagnetic properties, satisfactory stability, and intense chemiluminescence (CL) emission when reacted with H2O2, which was more than 150 times that of ABEI functionalized MBs. Furthermore, it was found that 2,4,6-trinitrotoluene (TNT) aptamer could attach to the surface of Co2+/ABEI/MBs via electrostatic interaction and coordination interaction between TNT aptamer and Co2+, leading to a decrease in CL intensity due to the catalytic site Co2+ being blocked by the aptamer. In the presence of TNT, TNT would bind strongly with TNT aptamer and detach from the surface of Co2+/ABEI/MBs, resulting in partial restoration of the CL signal. Accordingly, label-free aptasensor was developed for the determination of TNT in the range of 0.05-25 ng/mL with a detection limit of 17 pg/mL. This work demonstrates that Co2+/ABEI/MBs are easily connected with recognition biomolecules, which are not only magnetic carriers but also direct sensing interfaces with excellent CL activity. It provides a novel CL interface with a magnetic property which easily separates analytes from the sample matrix to construct label-free bioassays.

Catalyst-free synthesis of 3-sulfone nitrile from sulfonyl hydrazides and acrylonitrile in water.

A novel catalyst-free sulfonation reaction for synthesizing 3-sulfone nitrile compounds from sulfonyl hydrazides and acrylonitriles in water, without any metal catalyst, ligand or organic solvent, was demonstrated. This catalyst-free protocol provides a new synthetic method for the construction of 3-sulfone nitrile compounds with excellent yields. The D2O experiment adequately proved that the catalyst-free sulfonation reaction occurs via a Michael addition mechanism and that the hydrogen of 3-sulfone nitrile comes from water.

A label-free method for the detection of specific DNA sequences using gold nanoparticles bifunctionalized with a chemiluminescent reagent and a catalyst as signal reporters.

Sensitive, specific, simple, fast, and low-cost DNA detection methods are extremely important in clinical diagnostics, gene therapy, and a variety of biomedical studies. In this work, we developed a general method for the detection of specific DNA sequences from Mycobacterium tuberculosis (TB), hepatitis B virus (HBV), and myelocytomatosis viral oncogene (v-myc) using gold nanoparticles bifunctionalized with both a chemiluminescent (CL) reagent and a catalytic metal complex as signal reporters and a DNA strand complementary to the target as the capture probe. In this CL method, a biotinylated single-strand DNA capture probe was immobilized in a streptavidin-coated microwell. Upon the addition of the target single-strand DNA, the capture probe hybridized with the target DNA. After adding the bifunctionalized gold nanoparticles and H2O2, a well-defined CL signal was obtained, and the CL intensity was observed to change as the target DNA concentration was increased. It was possible to determine the concentration of the target TB single-strand DNA in the range 1.0 × 10-13-1.0 × 10-8 M with a detection limit of 4.8 × 10-14 M. HBV single-strand DNA and v-myc single-strand DNA could also be determined in the range 1.0 × 10-11-1.0 × 10-8 M with detection limits of 5.9 × 10-12 M and 8.0 × 10-12 M, respectively, using this CL technique. The method reported in this paper is the first label-free CL method for the determination of specific DNA sequences to utilize gold nanoparticles bifunctionalized with both a CL reagent and a catalytic metal complex. The sensitivity of this CL method is superior to those of most previously reported label-free methods. Compared with methods that use polymerase chain reaction amplification, this label-free CL method is much simpler, faster, and more economic. This work has thus demonstrated a simple and fast scanning strategy for the detection of specific DNA sequences related to diseases. Graphical Abstract Schematic illustration of label-free CL method for detection of specific DNA sequences.

Transcriptome analysis of an endoparasitoid wasp Cotesia chilonis (Hymenoptera: Braconidae) reveals genes involved in successful parasitism.

For successful parasitization, parasitiods usually depend on the chemosensory cues for the selection of hosts, as well as a variety of virulence factors introduced into their hosts to overcome host immunity and prevent rejection of progeny development. In bracovirus-carrying wasps, the symbiotic polydnaviruses act in manipulating development and immunity of hosts. The endoparasitoid Cotesia chilonis carrying bracovirus as a key host immunosuppressive factor is a superior endoparasitoid of rice stem borer, Chilo suppressalis. So far, genomic information for C. chilonis is not available and transcriptomic data may provide valuable resources for global studying on physiological processes of C. chilonis, including chemosensation and parasitism at molecular level. Here, we performed RNA-seq to characterize the transcriptome of C. chilonis adults. We obtained 27,717,892 reads, assembled into 38,318 unigenes with a mean size of 690 bp. Approximately, 62.1% of the unigenes were annotated using NCBI databases. A large number of chemoreception-related genes encoding proteins including odorant receptors, gustatory receptors, odorant-binding proteins, chemosensory proteins, transient receptor potential ion channels, and sensory neuron membrane proteins were identified in silico. Totally, 72 transcripts possessing high identities with the bracovirus-related genes were identified. We investigated the mRNA expression levels of several transcripts at different developmental stages (including egg, larva, pupae, and adult) by quantitative real-time PCR analysis. The results revealed that some genes had adult-specific expression, indicating their potential significance for mating and parasitism. Overall, these results provide comprehensive insights into transcriptomic data of a polydnavirus-carrying parasitoid of a rice pest.

THE ENDOPARASITOID Pteromalus puparum INFLUENCES HOST GENE EXPRESSION WITHIN FIRST HOUR OF PARASITIZATION.

The small cabbage butterfly, Pieris rapae, is an important pest of cruciferous corps, and Pteromalus puparum is a predominant pupal endoparasitoid wasp of this butterfly. For successful development of parasitoid offspring, female parasitoids usually introduce one or several kinds of maternal factors into the hemocoels during oviposition to suppress host immunity. To investigate the early changes in host immune-related genes following parasitization, we analyzed transcriptomes of parasitized and unparasitized, control, host pupae. Approximately 17.7 and 19.3 million paired-end reads were generated from nonparasitized and parasitized host pupae, and assembled de novo into 45,639 transcripts and 27,659 nonredundant unigenes. The average unigene length was 790 bp. A total 18,377 of 27,659 unigenes were annotated and we identified 557 differentially expressed unigenes in host pupae at 1 h after parasitization, of which 21 were immune-related. Parasitization led to downregulation of most pattern recognition receptors and upregulation of all serine protease inhibitors. The transcirptomic profile of P. rapae is considerably affected by parasitization. This study provides valuable sources for future investigations of the molecular interaction between P. puparum and its host P. rapae.

Dynamically tunable chemiluminescence of luminol-functionalized silver nanoparticles and its application to protein sensing arrays.

It is still a great challenge to develop an array-based sensing system that can obtain only multiparameters, according to a single experiment and device. The role of conventional chemiluminescence (CL) in biosensing has been limited to a signal transducer in which a single signal (CL intensity) can be obtained for quantifying the concentrations of analytes. In this work, we have developed an dynamically tunable CL system, based on the reaction of luminol-functionalized silver nanoparticles (luminol-AgNPs) with H2O2, which could be tunable via adjusting various conditions such as the concentration of H2O2, pH value, and addition of protein. A single experiment operation could obtain multiparameters including CL intensity, the time to appear CL emission and the time to reach CL peak value. The tunable, low-background, and highly reproducible CL system based on luminol-AgNPs is applied, for the first time, as a sensing platform with trichannel properties for protein sensing arrays by principal component analysis. Identification of 35 unknowns demonstrated a success rate of >96%. The developed sensing arrays based on the luminol-AgNPs provide a new way to use nanoparticles-based CL for the fabrication of sensing arrays and hold great promise for biomedical application in the future.

A general chemiluminescence strategy for measuring aptamer-target binding and target concentration.

Although much effort has been made for studies on aptamer-target interactions due to promising applications of aptamers in biomedical and analytical fields, measurement of the aptamer-target binding constant and binding site still remains challenging. Herein, we report a sensitive label-free chemiluminescence (CL) strategy to determine the target concentration and, more importantly, to measure the target-aptamer binding constant and binding site. This approach is suitable for multiple types of targets, including small molecules, peptides, and proteins that can enhance the CL initiated by N-(aminobutyl)-N-ethylisoluminol functionalized gold colloids, making the present method a general platform to investigate aptamer-target interactions. This approach can achieve extremely high sensitivity with nanogram samples for measuring the target-aptamer binding constant. And the measurement could be rapidly performed using a simple and low-cost CL system. It provides an effective tool for studying the binding of biologically important molecules to nucleic acids and the selection of aptamers. Besides, we have also discovered that the 14-mer aptamer fragment itself split from the ATP-binding aptamer could selectively capture ATP. The binding constant, site, and conformation between ATP and the 14-mer aptamer fragment were obtained using such a novel CL strategy and molecular dynamic simulation.

Advances in MXene-based luminescence sensing strategies.

MXenes have attracted the attention of many researchers as one of the latest two-dimensional (2D) materials over the last decade. Their great potential for biosensing has also been fully exploited after the discovery of their unique properties such as superior optical properties, excellent hydrophilicity, good thermal stability, excellent mechanical property, high electrical conductivity, biocompatibility, large surface area, and ease of surface functionalization. In the MXene-based luminescence sensing strategy, MXenes typically appear in the form of nanosheets, quantum dots and modified MXene nanocomposites, and they are utilized as different sensing platforms or as a luminescence source. In this review, we focused on the MXene-based luminescence sensing strategies, including fluorescence, electrochemiluminescence and chemiluminescence sensors and the comparison of their performance. Finally, the perspectives of the MXene-based luminescence sensors are discussed.

The Development of an Oral Solution Containing Nirmatrelvir and Ritonavir and Assessment of Its Pharmacokinetics and Stability.

Paxlovid®, a co-packaged medication comprised of separate tablets containing two active ingredients, nirmatrelvir (NRV) and ritonavir (RTV), exhibits good effectiveness against coronavirus disease 2019 (COVID-19). However, the size of the NRV/RTV tablets makes them difficult for some patients to swallow, especially the elderly and those with dysphagia. Therefore, an oral liquid formulation that can overcome this shortcoming and improve patient compliance is required. In this study, we developed a liquid formulation containing NRV and RTV by adopting strategies that used co-solvents and surfactants to enhance the solubility and inhibit possible recrystallization. The in vitro release results showed that NRV and RTV could be maintained at high concentrations in solution for a certain period in the investigated media. In vivo studies in rats showed that the oral bioavailability of NRV/RTV solution was significantly enhanced. Compared to Paxlovid® tablets, the AUC(0-t) of NRV and RTV increased by 6.1 and 3.8 times, respectively, while the Cmax increased by 5.5 times for both. Furthermore, the promoting effect of the absorption of RTV on the bioavailability of NRV was confirmed. Experiments with a beagle showed a similar trend. Stability studies were also conducted at 4 °C, 25 °C, and 40 °C for 90 days, indicating that the oral liquid formulation was physically and chemically stable. This study can be used as a valuable resource for developing and applying oral liquid NRV/RTV formulations in a clinical context.

Corrigendum: A rapid VEGF-gene-sequence photoluminescence detector for osteoarthritis.

[This corrects the article DOI: 10.3389/fbioe.2024.1338901.].

A rapid VEGF-gene-sequence photoluminescence detector for osteoarthritis.

Osteoarthritis (OA) has become a serious problem to the human society for years due to its high economic burden, disability, pain, and severe impact on the patient's lifestyle. The importance of current clinical imaging modalities in the assessment of the onset and progression of OA is well recognized by clinicians, but these modalities can only detect OA in the II stage with significant structural deterioration and clinical symptoms. Blood vessel formation induced by vascular endothelial growth factor (VEGF) occurs in the early stage and throughout the entire course of OA, enables VEGF relating gene sequence to act as a biomarker in the field of early diagnosis and monitoring of the disease. Here in, a facile rapid detection of VEGF relating ssDNA sequence was developed, in which manganese-based zeolitic imidazolate framework nanoparticles (Mn-ZIF-NPs) were synthesized by a simple coprecipitation strategy, followed by the introduction and surficial absorption of probe ssDNAs and the CRISPR/Cas12a system components. Furthermore, fluorescence experiments demonstrated that the biosensor displayed a low detection limit of 2.49 nM, a good linear response to the target ssDNA ranging from 10 nM to 500 nM, and the ability of distinguishing single nucleotide polymorphism. This finding opens a new window for the feasible and rapid detection of ssDNA molecules for the early diagnose of OA.