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1.
Biomacromolecules ; 2024 May 09.
Article in English | MEDLINE | ID: mdl-38720431

ABSTRACT

Reactive oxygen species (ROS) have emerged as a promising treatment option for antibacterial and biofilm eradication. However, their therapeutic efficacy is significantly hampered by the unique microenvironments of diabetic wounds. In this study, we designed and synthesized porphyrin-based Fe covalent organic frameworks (Fe-COF) through a Schiff base condensation reaction. Subsequently, Fe-COF were encapsulated with hyaluronic acid (HA) through electrostatic adsorption, resulting in a novel formulation named HA-Fe-COF for diabetic wound healing. HA-Fe-COF were engineered to respond to hyaluronidase in the infected wound, leading to the controlled release of Fe-COF. Those released Fe-COF served a dual role as photosensitizers, generating singlet oxygen and localized heating when exposed to dual light sources. Additionally, they acted as peroxidase-like nanozymes, facilitating the production of ROS through enzymatic reactions. This innovative approach enabled a synergistic therapeutic effect combining photodynamic, photothermal, and chemodynamic modalities. Furthermore, the sustained release of HA from HA-Fe-COF promoted angiogenesis, collagen deposition, and re-epithelialization during the diabetic wound healing process. This "all-in-one" strategy offers a novel approach for the development of antimicrobial and biofilm eradication strategies that minimize damage to healthy tissues in vivo.

2.
Biosens Bioelectron ; 257: 116332, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38677016

ABSTRACT

In situ detection of dopamine (DA) at single-cell level is critical for exploring neurotransmitter-related biological processes and diseases. However, the low content of DA and a variety of distractors with similar oxidation potentials as DA in cells brought great challenges. Here, a sensitive and specific electrochemical nanosensor was proposed for in situ detection of DA in single living cells based on nanodiamond (ND) and molecularly imprinted polymer (MIP)-functionalized carbon fiber nanoelectrode (ND/MIP/CFNE). Due to its excellent electrocatalytic property, ND was modified to the surface of CFNE based on amide bonding. Compared with bare CFNE, ND-modified CFNE can enhance oxidation currents of DA by about 4-fold, improving signal-to-noise ratio and detection sensitivity. MIP was further electropolymerized on the surface of nanoelectrodes to achieve specific capture and recognition of DA, which could avoid the interference of complex matrix and analogs in cells. Taking advantage of the precise positioning capability of a single-cell analyzer and micromanipulator, ND/MIP/CFNE could be precisely inserted into different locations of single cells and monitor oxidation signal of DA. The concentration of DA in the cytoplasm of single pheochromocytoma (PC12) cell was measured to be about 0.4 µM, providing a sensitive and powerful method for single-cell detection. Furthermore, the nanoelectrodes can monitor the fluctuation of intracellular DA under drug stimulation, providing new ideas and methods for new drug development and efficacy evaluation.


Subject(s)
Biosensing Techniques , Dopamine , Electrochemical Techniques , Molecularly Imprinted Polymers , Single-Cell Analysis , Dopamine/analysis , Dopamine/chemistry , Biosensing Techniques/instrumentation , Biosensing Techniques/methods , PC12 Cells , Electrochemical Techniques/methods , Molecularly Imprinted Polymers/chemistry , Animals , Rats , Nanodiamonds/chemistry , Electrodes , Carbon Fiber/chemistry , Molecular Imprinting/methods , Limit of Detection , Polymers/chemistry
3.
Chem Commun (Camb) ; 60(27): 3649-3652, 2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38372355

ABSTRACT

Herein, silica microspheres with ordered mesopores are synthesized and applied as a stationary phase for supercritical fluid chromatography (SFC). The excellent particle monodispersity and pore orderliness coupled with the rapid analytes diffusion of the supercritical fluid lead to an ultra-high column efficiency of 340 000 plate per m.

4.
Intern Emerg Med ; 19(3): 721-730, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38386096

ABSTRACT

Acute-on-chronic liver failure (ACLF) implies high short-term mortality rates and usually requires intensive care unit (ICU) admission. Proper prognosis for these patients is crucial for early referral for liver transplantation. The superiority of CLIF-C ACLF score in Asian patients with ACLF admitted to an ICU remains inconclusive when compared to other scoring systems. The purpose of the study is (i) to compare the predictive performance of original MELD, MELD-Lactate, CLIF-C ACLF, CLIF-C ACLF-Lactate, and APACHE-II scores for short-term mortality assessment. (ii) to build and validate a novel scoring system and to compare its predictive performance to that of the original five scores. Two hundred sixty-five consecutive cirrhotic patients with ACLF who were admitted to our ICU were enrolled. The prognostic values for mortality were assessed by ROC analysis. A novel model was developed and internally validated using fivefold cross-validation. Alcohol abuse was identified as the primary etiology of cirrhosis. The AUROC of the five prognostic scores were not significantly superior to each other in predicting 1-month and 3-month mortality. The newly developed prognostic model, incorporating age, alveolar-arterial gradient (A-a gradient), BUN, total bilirubin level, INR, and HE grades, exhibited significantly improved performance in predicting 1-month and 3-month mortality with AUROC of 0.863 and 0.829, respectively, as compared to the original five prognostic scores. The novel ACLF model seems to be superior to the original five scores in predicting short-term mortality in ACLF patients admitted to an ICU. Further rigorous validation is required.


Subject(s)
Acute-On-Chronic Liver Failure , Intensive Care Units , Humans , Acute-On-Chronic Liver Failure/mortality , Male , Female , Intensive Care Units/organization & administration , Intensive Care Units/statistics & numerical data , Middle Aged , Prognosis , Aged , Adult , ROC Curve , Severity of Illness Index , Predictive Value of Tests , APACHE
5.
Small ; : e2310247, 2024 Feb 17.
Article in English | MEDLINE | ID: mdl-38368267

ABSTRACT

Chemodynamic therapy (CDT) has emerged as a promising approach for treating infected diabetic wounds, while reliable imaging technology for simultaneous monitoring of ROS and therapeutic processes is still a formidable challenge. Herein, smart covalent organic framework (COF) nanoreactors (COF NRs) are constructed by hyaluronic acid (HA) packaged glucose oxidase (GOx) covalently linked Fe-COF for diabetic wound healing. Upon the breakdown of the HA protective layer, GOx consumes glucose to produce gluconic acid and hydrogen peroxide (H2 O2 ), resulting in decreased local pH and H2 O2 supplementation. Density functional theory (DFT) calculations show that Fe-COF has high catalytic activity towards H2 O2 , leading to in situ generation of hydroxyl radicals (·OH) for sterilization, and the localized downregulation of glucose effectively improved the microenvironment of diabetic wounds. Meanwhile, based on the near-infrared photothermal imaging of oxidized 3,3',5,5'-tetramethylbenzidine (oxTMB), the authors showed that TMB can be applied for the point-of-care testing of ·OH and glucose, and assessing the sterilization progress in vivo. More significantly, the facile photothermal signaling strategy can be extended to monitor various ROS-mediated therapeutic systems, enabling accurate prediction of treatment outcomes.

6.
Angew Chem Int Ed Engl ; 63(10): e202317571, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38230818

ABSTRACT

Insight into effect of deuterium isotopes on organic near-IR (NIR) emitters was explored by the use of self-assembled Pt(II) complexes H-3-f and HPh-3-f, and their deuterated analogues D-3-f and DPh-3-f, respectively (Scheme 2). In vacuum deposited thin film, albeit having nearly identical emission spectral feature maximized at ~810 nm, H-3-f and D-3-f exhibit remarkable difference in photoluminescence quantum yield (PLQY) of 29 % and 50 %, respectively. Distinction in PLQY is also observed for HPh-3-f (800 nm, 50 %) and DPh-3-f (798 nm, 67 %). We then elucidated the theoretical differences in the impact on near-infrared (NIR) luminescence between Pt(II) complexes and organic small molecules upon deuteration. The results establish a general guideline for the deuteration on NIR emission efficiency. From a perspective of practical application, NIR OLEDs based on D-3-f and DPh-3-f emitters attain EQEmax of 15.5 % (radiance 31,287 mW Sr-1 m-2 ) and 16.6 % (radiance of 32,279 mW Sr-1 m-2 ) at 764 nm and 796 nm, respectively, both of which set new records for NIR OLEDs of >750 nm.

7.
Anal Chem ; 96(5): 1852-1860, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38279192

ABSTRACT

The self-powered electrochemical sensor (SPES), an analytical sensing device without external power supply, is integrated with the dual function of power supply and detection performance, which lay the foundation for the development of intelligent and portable electrochemical sensing devices. Herein, a novel SPES based on a zinc-air battery was constructed for the detection of hydrogen sulfide (H2S) in the lysate of colon cancer cells. Typically, an Fe/Fe3C@graphene foam with oxygen reduction performance was used to construct SPES based on a zinc-air battery (ZAB-SPES), which brings the open-circuit voltage to 1.30 V. Among them, the poisoning effect of H2S causes the catalytic performance of the oxygen reduction catalyst to decrease, causing a significant decrease in the discharge voltage of ZAB. Based on this principle, ZAB-SPES was constructed for the detection of H2S using a digital multimeter. The proposed ZAB-SPES demonstrated good selectivity and reproducibility for detecting H2S compared to the results of the H2S-specific fluorescence probe. This strategy enriches the idea of constructing a self-powered sensor and a digital multimeter as detection devices, providing technical support for the portability of SPESs.

8.
Anal Bioanal Chem ; 416(1): 163-173, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37930375

ABSTRACT

Alpha-fetoprotein (AFP) is inextricably linked to various diseases, including liver cancer. Thus, detecting the content of AFP in biology has great significance in diagnosis, treatment, and intervention. Motivated by the urgent need for affordable and convenient electronic sensors in the analysis and detection of aqueous biological samples, we combined the solution-gated graphene transistor (SGGT) with the catalytic reaction of enzyme nanoprobes (HRP-AuNPs-Ab2) to accurately sense AFP. The SGGT immunosensor demonstrated high specificity and stability, excellent selectivity, and excessive linearity over a range of 4 ng/mL to 500 ng/mL, with the lower detection limit down to 1.03 ng/mL. Finally, clinical samples were successfully detected by the SGGT immunosensor, and the results were consistent with chemiluminescence methods that are popular in hospitals for detecting AFP. Notably, the SGGT immunosensor is also recyclable, so it has excellent potential for use in high-throughput detection.


Subject(s)
Biosensing Techniques , Graphite , Metal Nanoparticles , Humans , alpha-Fetoproteins/analysis , Gold , Biosensing Techniques/methods , Electrochemical Techniques/methods , Immunoassay/methods , Limit of Detection
9.
Article in English | MEDLINE | ID: mdl-38049372

ABSTRACT

Near-infrared organic light-emitting diodes (NIR OLEDs) have significant potential for wearable phototherapeutic applications because of the unique properties of the OLEDs, including their free-form electronics and the excellent biomedical effects of NIR emission. In spite of their tremendous promise, given that the majority of NIR OLEDs in previous research have relied on the utilization of an intrinsically brittle indium tin oxide (ITO) electrode, their practicality in the field of wearable electronics is inherently constrained. Here, we report wearable and wavelength-tunable NIR OLEDs that employ a high-performance NIR emitter and an innovative architecture by replacing the ITO with a silver (Ag) electrode. The NIR OLEDs permit wavelength tuning of emissions from 700 to 800 nm and afford stable operation even under repeated bending conditions. The NIR OLEDs provide a lowered device temperature of 37.5 °C even during continuous operation under several emission intensities. In vitro experiments were performed with freshly fabricated NIR OLEDs. The outcomes were evaluated against experimental results performed using the same procedure utilizing blue, green, and red OLEDs. When exposed to NIR light irradiation, the promoting effect of cell proliferation surpassed the proliferative responses observed under the influence of visible light irradiation. The proliferation effect of human hair follicle dermal papilla cells is clearly related to the irradiation wavelength and time, thus underscoring the potential of wavelength-tunable NIR OLEDs for efficacious phototherapy. This work will open novel avenues for wearable NIR OLEDs in the field of biomedical application.

10.
Mikrochim Acta ; 190(11): 459, 2023 11 03.
Article in English | MEDLINE | ID: mdl-37921998

ABSTRACT

N-doped carbon Co/CoOx with laccase-like activity was directionally designed by pyrolyzing Co-coordination polymer and applied to detect epinephrine, which revealed a new preparation strategy for laccase mimics. The formation mechanism of the N-doped carbon Co/CoOx nanozyme was reconnoitered by a thermogravimetric-mass spectrometry system (TG-MS). N-doped carbon Co/CoOx exhibited outstanding laccase-like activity, and the Michaelis-Menten constant and maximum initial velocity were calculated to be 0.087 mM and 0.0089 µM s-1, respectively. Based on this principle, a simple colorimetric sensing platform was developed for the quantitative detection of epinephrine, which can be used to diagnose pheochromocytoma. In addition, the visual platform for detecting epinephrine exhibited a linear range of 3 to 20 µg mL-1 and a calculated detection limit of 0.42 µg mL-1. Therefore, the proposed colorimetric sensing platform is a promising candidate to be applied in precise early pheochromocytoma diagnosis.


Subject(s)
Adrenal Gland Neoplasms , Pheochromocytoma , Humans , Laccase , Carbon , Epinephrine
11.
Diagnostics (Basel) ; 13(20)2023 Oct 10.
Article in English | MEDLINE | ID: mdl-37891981

ABSTRACT

BACKGROUND: Acute-on-chronic-liver failure (ACLF) demonstrates high short-term mortality rates and usually requires intensive care unit (ICU) admission. Accurate prognostication of these patients is pivotal for timely referral for liver transplantation. The superiority of CLIF-C ACLF, CLIF-C ACLF lactate, and NACSELD-ACLF scores in Asian patients with ACLF admitted to an ICU remains inconclusive. AIMS: To compare the predictive performance of CLIF-C ACLF, CLIF-C ACLF lactate, and NACSELD-ACLF scores for one-month mortality. METHODS: 276 consecutive cirrhotic patients with ACLF admitted to ICU were enrolled. The prognostic values for one-month mortality were assessed by AUROC analysis. RESULTS: The primary cause of cirrhosis in this cohort was alcohol abuse (56.5%). AUROC analysis (95% confidence intervals) demonstrated that CLIF-C ACLF lactate [0.802 (0.747-0.856)] outperformed both CLIF-C ACLF [0.791 (0.733-0.848)] and NACSELD-ACLF [0.673 (0.606-0.740)] in predicting one-month mortality. However, no statistically significant difference was observed between the predictive abilities of CLIF-C ACLF and CLIF-C ACLF lactate. CONCLUSIONS: In critically ill cirrhotic patients with ACLF admitted to the hepatology ICU, CLIF ACLF-lactate outperformed CLIF-C ACLF and NACSELD-ACLF in predicting one-month mortality. Nevertheless, no statistically significant difference was observed between CLIF-C ACLF and CLIF-C ACLF lactate. Larger-scale multi-center prospective studies are warranted to validate these results.

12.
J Pers Med ; 13(10)2023 Oct 13.
Article in English | MEDLINE | ID: mdl-37888101

ABSTRACT

BACKGROUND: Recurrent common bile duct stone after endoscopic retrograde cholangiopancreatography is an undesirable problem, even when a following cholecystectomy is carried out. Important factors are the composition and properties of stones; the most significant etiology among these is the lipid level. While numerous studies have established the association between serum lipid levels and gallstones, no study has previously reported on recurrent common bile duct stones after endoscopic sphincterotomy with following cholecystectomy. MATERIALS AND METHODS: We retrospectively collected 2016 patients underwent endoscopic sphincterotomy from 1 January 2015 to 31 December 2017 in Linkou Chang Gung Memorial Hospital. Finally, 303 patients whose serum lipid levels had been checked following a cholecystectomy after ERCP were included for analysis. We evaluated if metabolic factors including body weight, BMI, HbA1C, serum lipid profile, and lipid-lowering drugs may impact the rate of common bile duct stone recurrence. Furthermore, we tried to find if there is any factor that may impact time to recurrence. RESULTS: A serum HDL level ≥ 40 (p = 0.000, OR = 0.207, 95% CI = 0.114-0.376) is a protective factor, and a total cholesterol level ≥ 200 (p = 0.004, OR = 4.558, 95% CI = 1.625-12.787) is a risk factor of recurrent common bile duct stones after endoscopic sphincterotomy with cholecystectomy. Lipid-lowering drugs, specifically statins, have been shown to reduce the risk of recurrence significantly (p = 0.003, OR = 0.297, 95% CI = 0.132-0.665). No factors were found to impact the time to recurrence in this study. CONCLUSIONS: The serum lipid level could influence the recurrence of common bile duct stones after endoscopic sphincterotomy followed by cholecystectomy, and it appears that statins can reduce the risk of recurrence.

13.
Anal Chim Acta ; 1269: 341341, 2023 Aug 15.
Article in English | MEDLINE | ID: mdl-37290849

ABSTRACT

It is a great challenge to develop an effective super-sensitive capture method for multiplex heavy metal ions (HMIs), because HMIs is extremely toxic to public health and the environment, what's more their contamination is usually multiplex ions pollution. In this work, a 3D high-porous conductive polymer hydrogel was designed and prepared with high-stable and easy mass production, which is very favorable for the industrialization. The polymer hydrogel (g-C3N4-P(Ani-Py)-PAAM) was formed from the mixture of aniline pyrrole copolymer and acrylamide cross-linked with phytic acid as dopant and cross-linker and integrated with g-C3N4. The 3D networked high-porous hydrogel not only exhibits excellent electrical conductivity, but also provides a large surface area for increasing the number of immobilized ions. Importantly, the 3D high-porous conductive polymer hydrogel was applied successfully in electrochemical multiplex sensing of HIMs. The prepared sensor used differential pulse anodic stripping voltammetry exhibited high sensitivities, low detection limit and wide detection ranges for Cd2+, Pb2+, Hg2+ and Cu2+, respectively. Moreover, the sensor showed a high accuracy in lake water test. The preparation and application of the hydrogel in electrochemical sensor provided an availability strategy to capture and detect the various HMIs by electrochemistry in solution and has great commercial application prospect.


Subject(s)
Metals, Heavy , Phytic Acid , Porosity , Hydrogels , Polymers , Electric Conductivity , Ions
14.
Cancers (Basel) ; 15(11)2023 May 31.
Article in English | MEDLINE | ID: mdl-37296962

ABSTRACT

Fully covered self-expandable metallic stents (FCSEMSs) are inserted in patients with unresectable pancreatic ductal adenocarcinoma (PDAC) to resolve malignant distal bile duct obstructions. Some patients receive FCSEMSs during primary endoscopic retrograde cholangiopancreatography (ERCP), and others receive FCSEMSs during a later session, after the placement of a plastic stent. We aimed to evaluate the efficacy of FCSEMSs for primary use or following plastic stent placement. A total of 159 patients with pancreatic adenocarcinoma (m:f, 102:57) who had achieved clinical success underwent ERCP with the placement of FCSEMSs for palliation of obstructive jaundice. One-hundred and three patients had received FCSEMSs in a first ERCP, and 56 had received FCSEMSs after prior plastic stenting. Twenty-two patients in the primary metal stent group and 18 in the prior plastic stent group had recurrent biliary obstruction (RBO). The RBO rates and self-expandable metal stent patency duration did not differ between the two groups. An FCSEMS longer than 6 cm was identified as a risk factor for RBO in patients with PDAC. Thus, choosing an appropriate FCSEMS length is an important factor in preventing FCSEMS dysfunction in patients with PDAC with malignant distal bile-duct obstruction.

15.
Talanta ; 260: 124613, 2023 Aug 01.
Article in English | MEDLINE | ID: mdl-37146454

ABSTRACT

Covalent organic framework (COF), a kind of porous polymer with crystalline properties, is a periodic porous framework material with precise regulation at atomic level, which can be formed by the orderly connection of pre-designed organic construction units through covalent bonds. Compared with metal-organic frameworks, COFs exhibit unique performance, including tailor-made functions, stronger load ability, structural diversity, ordered porosity, intrinsic stability and excellent adsorption features, are more conducive to the expansion of electrochemical sensing applications and the universality of applications. In addition, COFs can accurately integrate organic structural units with atomic precision into ordered structures, so that the structural diversity and application of COFs can be greatly enriched by designing new construction units and adopting reasonable functional strategies. In this review, we mainly summarized state-of-the-art recent advances of the classification and synthesis strategy of COFs, the design of functionalized COF for electrochemical sensors and COFs-based electrochemical sensing. Then, an overview of the considerable recent advances made in applying outstanding COFs to establish electrochemical sensing platform, including electrochemical sensor based on voltammetry, amperometry, electrochemical impedance spectroscopy, electrochemiluminescence, photoelectrochemical sensor and others. Finally, we discussed the positive outlooks, critical challenges and bright directions of COFs-based electrochemical sensing in the field of disease diagnosis, environmental monitoring, food safety, drug analysis, etc.

16.
ACS Sens ; 8(5): 2011-2020, 2023 05 26.
Article in English | MEDLINE | ID: mdl-37083364

ABSTRACT

Single-particle collision electrochemistry (SPCE) has shown great promise in biosensing applications due to its high sensitivity, high flux, and fast response. However, a low effective collision frequency and a large number of interfering substances in complex matrices limit its broad application in clinical samples. Herein, a novel and universal SPCE biosensor was proposed to realize sensitive detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) based on the collision and oxidation of single silver nanoparticles (Ag NPs) on polysulfide-functionalized gold ultramicroelectrodes (Ps-Au UMEs). Taking advantage of the strong interaction of the Ag-S bond, collision and oxidation of Ag NPs on the Ps-Au UME surface could be greatly promoted to generate enhanced Faraday currents. Compared with bare Au UMEs, the collision frequency of Ps-Au UMEs was increased by 15-fold, which vastly improved the detection sensitivity and practicability of SPCE in biosensing. By combining magnetic separation, liposome encapsulation release, and DNAzyme-assisted signal amplification, the SPCE biosensor provided a dynamic range of 5 orders of magnitude for spike proteins with a detection limit of 6.78 fg/mL and a detection limit of 21 TCID50/mL for SARS-CoV-2. Furthermore, SARS-CoV-2 detection in nasopharyngeal swab samples of infected patients was successfully conducted, indicating the potential of the SPCE biosensor for use in clinically relevant diagnosis.


Subject(s)
COVID-19 , Metal Nanoparticles , Humans , SARS-CoV-2 , Microelectrodes , Metal Nanoparticles/chemistry , COVID-19/diagnosis , Electrochemistry , Silver
17.
ACS Appl Mater Interfaces ; 15(18): 21917-21928, 2023 May 10.
Article in English | MEDLINE | ID: mdl-37105764

ABSTRACT

The in situ detection of low-content cancer biomarkers by an endogenous activator instead of an exogenous initiator in vitro remains a great challenge, leaving a gap in the development of a tumor-specific nanosensor with an endogenous protease-activatable manner. Herein, we proposed an endogenous protease-activatable nanosensor (PA-NS) guided by peptide nucleic acid-peptide-DNA copolymers to realize AND-gated and dual-model sensing of miRNA-21 (miR-21) by combining electrochemical detection with optical imaging in living tumor cells, without an additional introduction of an exogenous activator or nanomaterials. Moreover, the PA-NS can only be activated by "dual keys" (overexpressed miR-21 and cathepsin B protease in tumor cells) simultaneously, which enables effective improvement of the tumor-to-healthy cells ratio. The fluorescence intensity measured in single tumor cells was ∼3.5-fold higher than that in single healthy cells, and the electrochemical response decreased ∼30% in the presence of target miRNA. Furthermore, studies on regulation of the protease activity and miR-21 fluctuation under external stimulation have contributed to our understanding of the biological processes and drug screenings underlying disease development. This specific endogenous protease-mediated manner for dual-model detection of miRNA guarantees excellent tumor-selective capability, which offers new opportunities to study cell heterogeneity and provides more reliable fundamentals for the diagnosis and treatment of cancer down to the single-cell level.


Subject(s)
MicroRNAs , Neoplasms , Peptide Nucleic Acids , Humans , MicroRNAs/genetics , Peptide Hydrolases , Neoplasms/diagnosis , DNA , Peptides
18.
Chem Soc Rev ; 52(4): 1215-1272, 2023 Feb 20.
Article in English | MEDLINE | ID: mdl-36601686

ABSTRACT

Together with the development of two-dimensional (2D) materials, transition metal dichalcogenides (TMDs) have become one of the most popular series of model materials for fundamental sciences and practical applications. Due to the ever-growing requirements of customization and multi-function, dozens of modulated structures have been introduced in TMDs. In this review, we present a systematic and comprehensive overview of the structure modulation of TMDs, including point, linear and out-of-plane structures, following and updating the conventional classification for silicon and related bulk semiconductors. In particular, we focus on the structural characteristics of modulated TMD structures and analyse the corresponding root causes. We also summarize the recent progress in modulating methods, mechanisms, properties and applications based on modulated TMD structures. Finally, we demonstrate challenges and prospects in the structure modulation of TMDs and forecast potential directions about what and how breakthroughs can be achieved.

19.
Anal Chim Acta ; 1239: 340743, 2023 Jan 25.
Article in English | MEDLINE | ID: mdl-36628736

ABSTRACT

Covalent-organic frameworks (COFs), a kind of conjugate crystalline polymers, has great potential for high performance electrochemical sensors due to high porosity, controllable pores and structure, and large specific surface area, etc. Herein, we developed an electrochemical sensor based on confined synthesis of gold nanoparticles @ 1,3,5-triformylphloroglucinol (Tp) and benzidine (BD) connected COFs (Au NPs@TpBD-COFs) for electrochemical detection of bisphenol A (BPA). Firstly, Au NPs were grown on the surface and in the pores of COFs by confinement synthesis strategy, which aimed to improve the conductivity and catalytic activity of COFs. Then, this composite was used to constitute electrochemical sensor for the oxidation of BPA, resulting a good electrocatalytic activity in the phosphate buffer solution (pH 7.4). Due to high conductivity of Au NPs and TpBD-COFs recognize BPA via π-π stacking interactions and hydrogen bonds, the proposed sensor for the detection of BPA has the linear range of 5-1000 µM and the detection limit of 1 µM. Finally, the proposed sensor was used to measure the content of BPA in real water samples with a satisfactory recovery from 98.6 to 106.9%. Those good results confirmed that the proposed electrochemical sensors for monitoring of BPA in the application of COFs provided a significant guidance.


Subject(s)
Metal Nanoparticles , Metal-Organic Frameworks , Metal-Organic Frameworks/chemistry , Metal Nanoparticles/chemistry , Gold/chemistry , Electrochemical Techniques/methods , Limit of Detection
20.
Food Chem ; 410: 135325, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-36610091

ABSTRACT

Aflatoxin B1 (AFB1) that is prone to contaminate corns brings a serious threat to human health. Therefore, it is of great significance to construct novel detection methods for AFB1 tracing. Here, methylamine perovskite quantum dots (MP QDs) encapsulated by ZIF-8 metal-organic frameworks (MP QDs@ZIF-8) were prepared and then ultra-stable electrochemiluminescence (ECL) sensors were developed. By the confinement of cavities structure, multiple MP QDs were crystallized and embedded inside ZIF-8 to form MP QDs@ZIF-8, achieving stable and robust ECL responds in aqueous environment. Further combined with AFB1-imprinted polymer, the constructed ECL sensor showed good selectivity and ultra-sensitivity (the detection limit was 3.5 fg/mL, S/N = 3) with a wide linear range from 11.55 fg/mL to 20 ng/mL for AFB1 quantification. Satisfactory recoveries in corn samples indicated the reliable practicability of the proposed sensor for AFB1 assay. This work provided a novel pathway in designing high-performance ECL sensing platform for food safety.


Subject(s)
Biosensing Techniques , Quantum Dots , Humans , Quantum Dots/chemistry , Aflatoxin B1/analysis , Zea mays , Oxides , Luminescent Measurements/methods , Biosensing Techniques/methods , Limit of Detection , Electrochemical Techniques/methods
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