Near-infrared imaging for visualizing the synergistic relationship between autophagy and NFS1 protein during multidrug resistance using an ICT-TICT integrated platform.

Drug resistance is a major challenge for cancer treatment, and its identification is crucial for medical research. However, since drug resistance is a multi-faceted phenomenon, it is important to simultaneously evaluate multiple target fluctuations. Recently developed fluorescence-based probes that can simultaneously respond to multiple targets offer many advantages for real-time and in situ monitoring of cellular metabolism, including ease of operation, rapid reporting, and their non-invasive nature. As such we developed a dual-response platform (Vis-H2S) with integrated ICT-TICT to image H2S and viscosity in mitochondria, which could simultaneously track fluctuations in cysteine desulfurase (NFS1 protein and H2S inducer) and autophagy during chemotherapy-induced multidrug resistance. This platform could monitor multiple endogenous metabolites and the synergistic relationship between autophagy and NFS1 protein during multidrug resistance induced by chemotherapy. The results indicated that chemotherapeutic drugs simultaneously up-regulate the levels of NFS1 protein and autophagy. It was also found that the NFS1 protein was linked with autophagy, which eventually led to multidrug resistance. As such, this platform could serve as an effective tool for the in-depth exploration of drug resistance mechanisms.

Water-Promoted Mild and General Michaelis-Arbuzov Reaction of Triaryl Phosphites and Aryl Iodides by Palladium Catalysis.

A Pd-catalyzed relatively general Michaelis-Arbuzov reaction of triaryl phosphites and aryl iodides for preparing useful aryl phosphonates was developed. Interestingly, water can greatly facilitate the reaction through a water-participating phosphonium intermediate rearrangement process, which also makes the reaction conditions rather mild. In comparison with the known methods, this reaction is milder and more general, as it exhibits excellent functional group tolerance, can be applied to various triaryl phosphites and aryl iodides, and can be extended to aryl phosphonites and phosphinites. A gram-scale reaction with a low catalyst loading also revealed its practicality and potential in large-scale preparation.

Ligand-Free Iron-Catalyzed Construction of C-P Bonds via Phosphorylation of Alcohols: Synthesis of Phosphine Oxides and Phosphine Compounds.

An efficient method for the construction of C-P(V) and C-P(III) bonds via the iron-catalyzed phosphorylation of alcohols under ligand-free conditions is disclosed. This strategy represents a straightforward process to prepare a series of phosphine oxides and phosphine compounds in good to excellent yields from the readily available alcohols and P-H compounds. A plausible mechanism is also proposed. We anticipate that this mode of transforming simple alcohols would apply in chemical synthesis widely.

Polycarboxyl ionic liquid functionalized Yb-MOFs nanoballs based dual-wavelength responsive photoelectrochemical aptasensor for the simultaneous determination of AFB1 and OTA.

Developing an accurate and precise approach for the simultaneous detection of ochratoxin A (OTA) and aflatoxin B1 (AFB1) is significant for food safety surveillance. Herein, a photoelectrochemical sensing platform was constructed based on polycarboxylic ionic liquid functionalized metal-organic framework integrated with gold nanoparticles (Yb-MOFs@AuNPs). Sulfhydryl functionalized hairpin DNA (hDNA) was immobilized on a Yb-MOFs@AuNPs modified glassy carbon electrode (GCE) surface through Au-S bond. After blocking residual active binding sites with BSA, gold nanoparticles-labeled AFB1 aptamer (AuNPs-Apt 1) and gold nanorods-labeled OTA aptamer (AuNRs-Apt 2) were introduced to construct a photoelectrochemical aptasensor for the simultaneous determination of AFB1 and OTA. Due to the surface plasmon resonance effect and the nanometer size effect of gold nanomaterials, the photoelectrochemical aptasensor can output photocurrent responses as being excited with different wavelengths at 520 nm and 808 nm, respectively. When the AFB1 and OTA concentration in the range of 0.001-50.0 ng mL-1, a good linear relationship between the photocurrent difference (ΔI) before and after recognizing targets and the logarithm of AFB1 or OTA concentration was obtained. The detection limits for AFB1 and OTA were 0.40 pg mL-1 and 0.19 pg mL-1, respectively. AFB1 and OTA in corn samples were detected simultaneously by the photoelectrochemical aptasensor.

Factors associated with workplace violence against Chinese healthcare workers: an online cross-sectional survey.

Objectives: Workplace violence (WPV) against healthcare workers (HCWs) has reached significant levels globally, impeding the quality and accessibility of healthcare systems. However, there is limited available knowledge regarding the determinants linked with WPV among HCWs and the discrepancies observed across various levels of hospitals in China. The objective of the present research was to investigate the factors linked to WPV and job satisfaction among HCWs in China. Methods: A self-developed questionnaire based on WeChat was employed to collect data. The questionnaire consisted of demographic information as well as occupational factors. To measure WPV, the Chinese version of the Workplace Violence Scale was utilized. Career satisfaction was assessed through two questions regarding career choices. The collected data was analyzed using descriptive analyses, chi-square tests, and multivariate logistic regressions. Results: A total of 3,781 valid questionnaires (1,029 doctors and 2,752 nurses) were collected. Among all participants, 2,201 (58.2%) reported experiencing at least one form of WPV in the past year, with emotional abuse being the most frequent occurrence (49.7%), followed by threats (27.9%). The multivariate logistic regression analysis revealed several risk factors associated with WPV, including male gender, shift work, senior professional title, bachelor's degree education, employment in secondary-level hospitals, and working over 50 h per week (p < 0.05). Career satisfaction among HCWs who experienced high levels of WPV was low, with only 11.2% remaining confident in their profession, and a mere 2.0% supporting their children pursuing careers in healthcare. Conclusion: WPV poses a significant challenge within the Chinese healthcare system. Efforts should be made to address the identified risk factors and promote a safe and satisfying working environment for HCWs.

A smart cysteine-activated and heavy-atom-free nano-photosensitizer for photodynamic therapy to treat cancers.

A smart and heavy-atom-free photoinactive nano-photosensitizer capable of being activated by cysteine at the tumor site to generate highly photoactive nano-photosensitizers that show strong NIR absorption and fluorescence with a good singlet oxygen quantum yield (16.8%) for photodynamic therapy is reported.

Design a dual-response two-photon fluorescent probe for simultaneous imaging of mitochondrial viscosity and peroxynitrite in a thrombosis model.

BACKGROUND: Venous thromboembolism is a sudden cardiovascular disease that can lead to death, and its pathologic development is closely related to vascular viscosity and inflammation. However, direct evidence from in vivo is really scarce. The key limitation is that the combined probes cannot detect multiple markers simultaneously, which may lead to unreliable results. Therefore, to develop a single probe that can simultaneously monitor the variations of viscosity in the vascular microenvironment as well as inflammation level during venous thrombosis. RESULTS: A dual-responsive two-photon fluorescent probe, Cou-ONOO, was designed and synthesized. Cou-ONOO provides a visualization tool for monitoring the viscosity of the vascular as well as the inflammatory marker ONOO‾ during thromboembolism via dual-channel simultaneous imaging. As a single probe that can recognize dual targets, Cou-ONOO effectively avoids the problems from unreliable results caused by complex synthesis and differences in intracellular localization, diffusion, and metabolism of different dyes as using combinatorial probes. Using Cou-ONOO, simultaneous imaging the variations of viscosity and ONOO‾at the cellular and tissue levels was successfully performed. In addition, Cou-ONOO also successfully visualized and tracked the viscosity of the vascular microenvironment and ONOO‾ during venous embolism in mice. SIGNIFICANCE: Experimental results show that both viscosity and inflammation are abnormally overexpressed in the microenvironment at the thrombus site during venous thrombosis. An intuitive visualization tool to elucidate the variations of viscosity as well as inflammation level in the vascular microenvironment during thrombosis was provided, which will facilitate a better clinical understanding of the pathological process of thrombosis.

Dual-wavelength responsive CuS@COF nanosheets for high-performance photothermal/photodynamic combination treatments.

Photothermal therapy (PTT) makes it difficult to achieve good performance on tumor treatments due to insufficient photothermal conversion efficiency, etc. Combining PTT with photodynamic therapy (PDT) and other therapeutic tools can significantly enhance the tumor-killing ability and has been widely used in the development of therapeutic platforms. Copper sulfide nanoparticle (CuS NP) photothermal reagents have the advantages of low toxicity and simple synthesis; therefore, combining CuS NPs with PDT photosensitizers is an effective strategy to construct a PTT/PDT combination therapeutic platform. However, PDT photosensitizers and photothermal agents generally assembled through hydrophobic interaction, suffer from low coating efficiency or the risk of drug leakage, thus seriously restricting their applications. To address these challenges, CuS NPs with excellent photothermal conversion performance were selected as the core material to prepare CuS@COF nanosheets through a dual-ligand assistant strategy with 4,7-bis(4-aminophenyl)-2,1,3-benzothiadiazole (BTD) and 2,4,6-trihydroxybenzene-1,3,5-tricarbaldehyde (TP). As a PTT/PDT combination therapeutic platform, CuS@COF nanosheets possess a porous TP-BDT-based COF shell, and it can sufficiently contact oxygen to provide high singlet oxygen (1O2) yield under 505 nm laser irradiation. Upon illumination with a 1064 nm laser, CuS@COF nanosheets can effectively convert the photon energy into thermal energy with a photothermal conversion efficiency of 63.4%. The results of the CCK8 experiment showed that the phototoxicity of the PTT/PDT combination treatment reached 85.1%, which was much higher than the effect of a single treatment. It was also confirmed in vivo that the tumor inhibition effect of the PDT/PTT combination treatment group was much greater than that of the single treatment group.

Perspectives of parents of adolescents with repeated non-suicidal self-injury on sharing their caretaking experiences with peers: a qualitative study.

Background: The prevalence of non-suicidal self-injury among adolescents has increased over the years. Most parents, however, are poorly informed and confused about this behavior. Sharing caretaking experiences with parents in similar situations seems to be beneficial. Nevertheless, few researchers have explored the views of parents who share their caretaking experiences with peers. Aim: This study aimed to investigate the perspectives of parents of adolescents with repeated non-suicidal self-injury on sharing their caretaking experiences with peers as well as the motivations for and barriers to this behavior. Methods: This qualitative study adopted a purposive sampling method. Participants (16 mothers and 2 fathers) were recruited from the mental health center of a tertiary hospital in Chengdu, Sichuan, China. A total of 18 semistructured face-to-face individual interviews were conducted. All interviews were audio-recorded and analyzed thematically using NVivo 11. Results: Three themes and nine subthemes were identified: (1) sharable caretaking experiences: reflection and transformation, self-emotional management, and diversified support; (2) motivations for sharing: empathy, reciprocity, and meaning; and (3) barriers to sharing: inadequate knowledge, low self-identity, and concerns for children. Conclusion: Parents accumulate a wealth of experience during their long-term care of adolescents with repeated non-suicidal self-injury. Although most parents are willing to share their caretaking experiences with peers, there are several barriers. Therefore, in order to increase parents' motivation to share, psychological education is necessary.

The effects of family environment cognition and its difference perceived by adolescents and their parents on the treatment effect of non-suicidal self-injury behaviors in adolescents: a 1-year prospective cohort study.

Introduction: Family environment is the primary environment for adolescent growth and development, which is believed to have an important impact on the occurrence of non-suicidal self-injury (NSSI) behavior in adolescents. This study aimed to explore the effects of family environment cognition and cognitive differences perceived by adolescents and their parents on the treatment effects of NSSI in adolescents and to provide more potential perspectives for NSSI treatment. Methods: A one-year prospective longitudinal sub-cohort investigation was carried out among 199 adolescents engaged in NSSI and one of their important guardians from the Longitudinal Psychosomatic Disease Study (LoPDS). The NSSI behaviors of adolescents were evaluated at 3 months, 6 months and 1 year after enrollment. The family environment scale (FES) and NSSI Behavior Questionnaire were used as assessment tools for family environment and adolescents NSSI behaviors. Multiple linear regression was used to investigate the role of family environment perception difference in the treatment effect of adolescent NSSI. Results: After one year of follow-up, the perceived self-injury impulse score in recent 2 weeks, self-injury impulse frequency in recent 2 weeks, total number of self-injury in recent 2 weeks decreased significantly. The higher the adolescent family cohesion (Beta: 1.130, 95% CI: 0.886,1.373; p=0.032), parental family expressiveness (Beta: 0.818, 95% CI: 0.375,1.260; p=0.037) and parental family active-recreational orientation score (Beta: 0.609, 95% CI: 0.236,0.981; p=0.048), the better the treatment effect. However, higher adolescent family conflict (Beta: -0.838, 95% CI: -1.377,-0.298; p=0.024) were associated with lower treatment outcomes. The greater the cognitive difference between parents and adolescents in family cohesion (Beta: -1.307, 95% CI: -2.074,-0.539; p=0.014) and family conflict(Beta: -0.665, 95% CI: -0.919,-0.410; p=0.037), the worse the therapeutic effect of NSSI might be. Discussion: There were certain differences in the cognition of family relationships between parents and adolescents, and subjective family relationship cognition and cognitive differences had a significant effect on the treatment effect of NSSI in adolescents. Helping them identify the cause of cognitive differences and conducting systematic family therapy from the points of difference may be another perspective to improve the treatment effect of NSSI in adolescents.

Insights into the antibacterial activity and antibacterial mechanism of silver modified fullerene towards Staphylococcus aureus by multiple spectrometric examinations.

Clarifying the antibacterial mechanism of silver (Ag)-based materials is of great significance for the rational design, synthesis, and evaluation of antimicrobials. Herein, detailed description of the antibacterial mechanism of a synthesized silver deposited fullerene material (Ag(I)-C60) towards Staphylococcus aureus was surveyed from the point of view of DNA damage by ultraviolet-visible spectroscopy (UV-vis), inductively coupled plasma mass spectrometry (ICP-MS), and liquid chromatography-mass spectrometry (LC-MS). The model material, Ag(I)-C60, was prepared by liquid-liquid interfacial precipitation method, and characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), thermos-gravimetric analysis (TGA), and nitrogen adsorption/desorption analysis. Ultra-efficient bacteriostatic rate of Ag(I)-C60 was found to be 88.98% under light irradiation for 20 min. UV-vis measurement of the composition changes of four DNA bases showed that they changed in the presence of Ag(I)-C60 under light irradiation, suggesting Ag(I)-C60 could destroy the cells and genetic material of Staphylococcus aureus and thereby inhibit its growth and reproduction. ICP-MS analysis demonstrated the releasing behavior of Ag+ from Ag-based materials. Finally, the transformation pathway of G, A, C, and T were measured by LC-MS, demonstrating the conversion of Adenine (m/z 136.06) to 8-OH-Ade (m/z 174.04). These collective results suggested that Ag(I)-C60 was a new ultra-efficient antibacterial by slowly releasing Ag+ in water and producing a large amount of ROS under light.

Palladium-Catalyzed Decarbonylative Annulation of 2-Arylbenzoic Acids with Internal Alkynes toward Phenanthrenes.

A palladium-catalyzed decarbonylative annulation of 2-arylbenzoic acids with internal alkynes via C(sp2)-H activation has been developed. A series of phenanthrenes were produced in moderate to good yield with good functional group tolerance. The mechanism study indicated that the C(sp2)-H activation should be the rate-determining step during the reaction.

The application and research progress of anti-angiogenesis therapy in tumor immunotherapy.

Tumor immunotherapy, as the focus of scientific research and clinical tumor treatment in recent years, has received extensive attention. Due to its remarkable curative effect and fewer side effects than traditional treatments, it has significant clinical benefits for the treatment of various advanced cancers and can improve cancer patient survival in the long term. Currently, most patients cannot benefit from immunotherapy, and some patients may experience tumor recurrence and drug resistance even if they achieve remission overcome. Numerous studies have shown that the abnormal angiogenesis state of tumors can lead to immunosuppressive tumor microenvironment, which affects the efficacy of immunotherapy. Actually, to improve the efficacy of immunotherapy, the application of anti-angiogenesis drugs to normalize abnormal tumor vessel has been widely confirmed in basic and clinical research. This review not only discusses the risk factors, mechanisms, and effects of abnormal and normalized tumor angiogenesis state on the immune environment, but summarizes the latest progress of immunotherapy combined with anti-angiogenic therapy. We hope this review provides an applied reference for anti-angiogenesis drugs and synergistic immunotherapy therapy.

Palladium-catalyzed and norbornene-mediated C-H amination and C-O alkenylation of aryl triflates.

The C-H amination and C-O alkenylation of aryl triflates was achieved through Pd/norbornene (NBE) cooperative catalysis. By this strategy, various ortho-alkenyl tertiary anilines including those bearing functional groups were produced in good to excellent yields. This reaction represents a new conversion model for phenoxides. It expands the scope of Catellani-type reactions and the application of phenoxides in organic synthesis.

An Antibacterial and Anti-Oxidative Hydrogel Dressing for Promoting Diabetic Wound Healing and Real-Time Monitoring Wound pH Conditions with a NIR Fluorescent Imaging System.

The design and synthesis of multifunctional chitosan hydrogels based on polymerized ionic liquid and a near-infrared (NIR) fluorescent probe (PIL-CS) is a promising strategy, which not only prevents the transition from acute to chronic wounds, but also provides prompt measures regarding microenvironmental alterations in chronic wounds. PIL-CS hydrogel can real-time visualize wound pH through in vivo NIR fluorescent imaging and also feature the pH-responsive sustained drug release, such as antioxidant, to eliminate reactive oxygen species (ROS) and to boost diabetic wound healing. PIL-CS hydrogel is specific, sensitive, stable, and reversible in response to pH changes at the wound site. It, therefore, enables real-time monitoring for a dynamic pH change in the microenvironment of irregular wounds. PIL-CS hydrogel is also designed to possess many merits including high water containment and swelling rate, good biocompatibility, electrical conductivity, antifreeze, tissue adhesion, hemostatic performance, and efficient antibacterial activity against MRSA. In vivo studies showed that PIL-CS hydrogel provided fast diabetic wound healing support, promoted vascular endothelial growth factor (VEGF) production, and reduced ROS and tumor necrosis factor (TNF-α) generation. The results support that the hydrogels coupled with NIR fluorescent probes can be an excellent diabetic wound dressing for enhancing and real-time monitoring skin restoration and regeneration.

Combining radiation and the ATR inhibitor berzosertib activates STING signaling and enhances immunotherapy via inhibiting SHP1 function in colorectal cancer.

BACKGROUND: Immune checkpoint inhibitors (ICIs) targeting programmed cell death protein 1 (PD-1) and programmed death-ligand 1 (PD-L1) have shown a moderate response in colorectal cancer (CRC) with deficient mismatch repair (dMMR) functions and poor response in patients with proficient MMR (pMMR). pMMR tumors are generally immunogenically "cold", emphasizing combination strategies to turn the "cold" tumor "hot" to enhance the efficacy of ICIs. ATR inhibitors (ATRi) have been proven to cooperate with radiation to promote antitumor immunity, but it is unclear whether ATRi could facilitate the efficacy of IR and ICI combinations in CRCs. This study aimed to investigate the efficacy of combining ATRi, irradiation (IR), and anti-PD-L1 antibodies in CRC mouse models with different microsatellite statuses. METHODS: The efficacy of combining ATRi, IR, and anti-PD-L1 antibodies was evaluated in CRC tumors. The tumor microenvironment and transcriptome signatures were investigated under different treatment regimens. The mechanisms were explored via cell viability assay, flow cytometry, immunofluorescence, immunoblotting, co-immunoprecipitation, and real-time quantitative PCR in multiple murine and human CRC cell lines. RESULTS: Combining ATRi berzosertib and IR enhanced CD8+ T cell infiltration and enhanced the efficacy of anti-PD-L1 therapy in mouse CRC models with different microsatellite statuses. The mechanistic study demonstrated that IR + ATRi could activate both the canonical cGAS-STING-pTBK1/pIRF3 axis by increasing cytosolic double-stranded DNA levels and the non-canonical STING signaling by attenuating SHP1-mediated inhibition of the TRAF6-STING-p65 axis, via promoting SUMOylation of SHP1 at lysine 127. By boosting the STING signaling, IR + ATRi induced type I interferon-related gene expression and strong innate immune activation and reinvigorated the cold tumor microenvironment, thus facilitating immunotherapy. CONCLUSIONS: The combination of ATRi and IR could facilitate anti-PD-L1 therapy by promoting STING signaling in CRC models with different microsatellite statuses. The new combination strategy raised by our study is worth investigating in the management of CRC.

A high performance dual-mode biosensor based on Nd-MOF nanosheets functionalized with ionic liquid and gold nanoparticles for sensing of ctDNA.

A dual-mode biosensor constructed based on photoelectrochemical (PEC) and electrochemical (EC) property was developed for assaying circulating tumor DNA (ctDNA), which is commonly used for triple-negative breast cancer diagnosis. Ionic liquid functionalized two-dimensional Nd-MOF nanosheets were successfully synthesized through a template-assisted reagent substituting reaction. Nd-MOF nanosheets integrated with gold nanoparticles (AuNPs) were able to improve photocurrent response and supply active sites for assembling sensing elements. To achieve selective detection of ctDNA, thiol-functionalized capture probes (CPs) were immobilized on the Nd-MOF@AuNPs modified glassy carbon electrode surface, thereby generating a "signal-off" photoelectrochemical biosensor for ctDNA under visible light irradiation. After the recognition of ctDNA, ferrocene-labeled signaling probes (Fc-SPs) were introduced into the biosensing interface. After hybridization between ctDNA and Fc-SPs, the oxidation peak current of Fc-SPs generated from square wave voltammetry can be employed as a "signal-on" electrochemical signal for ctDNA quantification. Under the optimized conditions, a linear relationship was obtained to the logarithm of ctDNA concentration in between 1.0 fmol L-1 to 10 nmol L-1 for the PEC model and 1.0 fmol L-1 to 1.0 nmol L-1 for the EC model. The dual-mode biosensor can provide accurate results for ctDNA assays, effectively eliminating the probable occurrence of false-positive or false-negative results in single-model assays. By switching DNA probe sequences, the proposed dual-mode biosensing platform can serve as a strategy for detecting other DNAs and possesses broad applications in bioassay and early disease diagnosis.

A near-infrared photoelectrochemical aptasensing system based on Bi2O2S nanoflowers and gold nanoparticles for high-performance determination of MCF-7 cells.

Circulating tumor cells (CTCs) are commonly considered as the major cause of tumor metastasis and can eventually lead to death. Therefore, developing a high-performance method for the determination of CTCs is very significant for promoting the cancer survival rate. Photoelectrochemical biosensing systems have been extensively investigated and applied for bioassays. Herein, Bi2O2S nanoflowers were successfully prepared through a simple one-step hydrothermal method. After being integrated with gold nanoparticles with a diameter of ∼45 nm, AuNPs/Bi2O2S nanocomposites were coated onto an ITO electrode surface to build a photoelectrochemical sensing platform which can be excited with near-infrared light to produce photocurrent response. Subsequently, mercapto-group functionalized aptamer (SH-Apt) was fixed onto the AuNPs/Bi2O2S/ITO surface. Due to the overexpress of MUC1 protein in the cell membrane, MCF-7 cells were specifically trapped on the SH-Apt/AuNPs/Bi2O2S/ITO surface. The introduce of MCF-7 cells lead to an obvious decrease on the photocurrent response. The photocurrent variation shows a satisfied linear relationship to the logarithm of MCF-7 cells concentration ranged from 50 to 6 × 105 cell mL-1. The detection limit obtained is 17 cell mL-1. The PEC biosensor shows excellent sensitivity, selectivity and stability for sensing MCF-7 cells, even for determining MCF-7 cells in clinical serum samples.

A near-infrared photoelectrochemical immunosensor for CA72-4 sensing based on SnS nanorods integrated with gold nanoparticles.

SnS nanorods with near-infrared photoelectric conversion characteristics were successfully synthesized through a simple hydrothermal method. Gold nanoparticles were self-assembled onto SnS nanorods surface to form SnS/AuNPs nanocomposites. The integration of AuNP can significantly improve the photocurrent response of SnS nanorods under being illuminated with 808 nm near-infrared light. A near-infrared photoelectrochemical immunosensing platform based on SNS/AuNPs nanocomposites was constructed for sensing gastric cancer tumor marker CA72-4. Experimental conditions were optimized to improve the immunosensing performances for CA72-4 determination. As CA72-4 concentration varied from 0.01 to 50 U mL-1, the photocurrent variation between the immunosensor before and after reacting with CA72-4 was linearly related to the logarithm of its concentration. The detection limit was calculated to be 0.008 U mL-1. The practicability of the immunosensor was demonstrated by determining CA72-4 in human serum samples.

Ionic liquid functionalized trapezoidal Zn-MOF nanosheets integrated with gold nanoparticles for photoelectrochemical immunosensing alpha-fetoprotein.

An imidazolium based ionic liquid was successfully prepared and used as an organic ligand to coordinate with Zn2+ to prepare trapezoidal metal-organic frameworks (Zn-MOF) nanosheets. Then, gold nanoparticles (AuNPs) were integrated onto Zn-MOF nanosheets surface to produce AuNPs@Zn-MOF nanocomposites by in-situ reduction of chloroauric acid. AuNPs with size less than 5 nm were uniformly dispersed on the entire surface of Zn-MOF nanosheets. AuNPs can significantly promote the photocurrent response of Zn-MOF nanosheets and supply an efficient photoelectrochemical sensing platform for fabricating an immunosensor for alpha-fetoprotein (AFP). For AFP determination, the photocurrent response of the immunosensor was linearly related to the logarithm of AFP concentration in the range of 0.005-15.0 ng/mL. The detection limit was calculated to be 1.88 pg/mL. The PEC immunosensor can be facilely fabricated, and provided some superior analytical characteristics such as excellent selectivity, sensitivity, stability and reproducibility for AFP determination. Practicability of the photoelectrochemical immunosensor was demonstrated by using it in assaying AFP in clinical serum samples.