Sensitive Detection Research Articles

Integration of 6-Thioguanine Functionalized Molybdenum-Copper Bimetallic Nanoclusters With Fluorescence Spectroscopy for the Sensitive Detection of Uric Acid in Biofluids.

In this paper, a single-step synthetic approach is presented for the development of bimetallic molybdenum-copper nanoclusters (Mo-CuNCs), shielded by a small molecule 6-thioguanine (6-TG). The Mo-CuNCs possessed a small size, high fluorescence, stable behavior, and good solubility in water. The 6-TG-Mo-CuNCs exhibit strong blue fluorescence emission at 410 nm after exciting at 330 nm as compared to its monometallic nanoclusters. Utilizing 6-TG-Mo-CuNCs superior biochemical stability, uric acid (UA) can be specifically detected as an oxidative stress biomarker using an inner filter effect mechanism. The probe demonstrated good sensing capability for detecting UA within the range of 0.09-5.00 μM and a detection limit of 0.237 μM. The method feasibility is further validated by quantifying UA in urine and plasma samples.

Amino-functionalized vertically ordered mesoporous silica film on electrochemically polarized screen-printed carbon electrodes for the construction of gated electrochemical aptasensors and sensitive detection of carcinoembryonic antigens

Disposable electrochemical biosensors with high sensitivity are very fit for point-of-care testing in clinical diagnosis. Herein, amino-functionalized, vertically ordered mesoporous silica films (NH2-VMSF) attached to an electrochemically polarized screen-printed carbon electrode (p-SPCE) are prepared using a simple electrochemical method and then utilized to construct a gated electrochemical aptasensor for rapid and sensitive determination of carcinoembryonic antigen (CEA). After being treated with the electrochemical polarization procedure, p-SPCE has plentiful oxygen-containing groups and improved catalytic ability, which help promote the stability of NH2-VMSF on SPCE without the use of an adhesive layer and simultaneously generate a highly electroactive sensing interface. Owing to the numerous uniform and ultrasmall nanopores of NH2-VMSF, CEA-specific aptamer anchored on the external surface of NH2-VMSF/p-SPCE serves as the gatekeeper, allowing the specific recognition and binding of CEA and eventually impeding the ingress of electrochemical probes [Fe(CN)63−/4−] through the silica nanochannels. The declined electrochemical responses of Fe(CN)63−/4− can be used to quantitatively detect CEA, yielding a wide detection range (100 fg/mL to 100 ng/mL) and a low limit of detection (24 fg/mL). Moreover, the proposed NH2-VMSF/p-SPCE-based electrochemical aptasensor can be applied to detect the amount of CEA in spiked human serum samples, which extends the biological application of a disposable NH2-VMSF/p-SPCE sensor by modulating the biological recognition species.

Electroactivated SERS Nanoplatform for Rapid and Sensitive Detection and Identification of Tumor-Derived Exosome miRNA.

Exosomal miRNA expression derived from tumor cells provides a valuable and promising noninvasive modality for the early diagnosis and assessment of the efficacy of cancer treatment. However, accurate detection and identification of miRNA within exosomes have been challenging due to its low abundance and the complexity and tedious extraction with large sample volumes in the separation process. Here, we developed an electrically activated nanoplatform for rapid and sensitive detection and identification of exosome miRNA, through triggering miRNA release by opening exosomes that were captured on the electrode surface using a slightly applied electric field (50 mV), and simultaneously detected them with surface-enhanced Raman spectroscopy (SERS) in situ. The method possessed superior specificity and sensitivity for exosomal miRNA detection, with a low detection concentration of 0.5 nM. The SERS sensor chips also showed a superior sensing performance of exosomal miRNA in complex body fluids such as urine and blood. We found that exosomal miRNA contents derived from tumor cells were significantly higher than those in normal cells, and importantly, the concentrations of exosomes secreted from three different cell lines were distinctly augmented after mild electrical stimulation (ES) treatment. Furthermore, the miRNA expression within exosomes was upregulated after the ES treatment of cells. The developed approach and SERS detection platform for exosomal miRNA are promising for noninvasive and precise screening, classification, and monitoring of cancer.

A Copper-Incorporatedmeso-(N'-acetyl-hydrizide)-BODIPY as a "Off-On" Fluorescent Probe for Histidine.

We present a highly sensitive and selective fluorescence "turn-on" sensor for L-histidine (His) detection in aqueous solutions utilizing a 1-Cu2+ complex. This sensing platform employs a fluorescence-based ligand displacement approach, featuring a meso-(N'-acetyl-hydrizide)-based BODIPY derivative (1) complexed with Cu2+. Initially highly fluorescent, the emission of 1 is selectively quenched by Cu2+ ions, forming the 1-Cu2+ complex. The high affinity between His and Cu2+ effectively displaces 1 from the complex, restoring fluorescence. The system exhibits rapid response (within 5 minutes), excellent sensitivity (detection limit of 78 nM), operational simplicity, and a large fluorescence "turn-on" signal. It demonstrates remarkable selectivity for His over other amino acids, with maleimide masking cysteine interference. Notably stable in complex biological matrices, the sensor has successfully quantified His in artificial urine samples. Its practical applicability extends to paper-based test strips, offering portability and potential for real-time His monitoring in clinical diagnostics and biological systems.

Rapid Dual-Gene Detection of Burkholderia gladioli and Subspecies Cocovenenans in Fresh Noodles and Tremella Using CRISPR-Cas12a/Cas13a.

Burkholderia gladioli pv. cocovenenans is a notable foodborne pathogen that poses a significant risk to food safety. Contaminated food requires distinct classification and treatment procedures for non-pathogenic B. gladioli and its pathogenic subspecies cocovenenans. Hence, establishing a rapid and sensitive detection method to distinguish them is necessary. In this study, we aimed to establish a method combining the CRISPR-Cas12a/Cas13a dual system with recombinase aided amplification for rapid, specific and sensitive detection of non-pathogenic B. gladioli and pathogenic subspecies cocovenenans in food. First, a RAA-CRISPR-Cas12a/Cas13a method was developed and its feasibility was assessed. Next, specificity was analyzed using 23 strains of B. gladioli and 5 non-target strains. Following this, sensitivity was evaluated by preparing gradient dilutions of B. gladioli pv. cocovenenans bacterial solutions. At last, real food test samples, including fresh noodles and tremella artificially contaminated with B. gladioli pv. cocovenenans, were utilized for method validation and sensitivity comparison. The established RAA-CRISPR-Cas12a/Cas13a method exhibited high specificity and achieved 100% accuracy in detecting species B. gladioli and its subspecies cocovenenans. This rapid method could be finished within 45 min with a detection limit of 10° CFU/mL for bacterial concentration. Additionally, it achieved detection limits of 102 CFU/g for fresh noodles and 103 CFU/g for tremella. The rapid RAA-CRISPR-Cas12a/Cas13a method demonstrated high specificity and sensitivity in detecting and disgusting species B. gladioli and subspecies cocovenenans in both food test samples and post-cultivation colonies. The RAA-CRISPR-Cas12a/Cas13a method presented in this study offers a novel molecular approach for the rapid, accurate and sensitive detection of B. gladioli and its subspecies cocovenenans in foods.

SERS-Based Microfluidic Bioscreening Platform for Selective Detection of β-Amyloid Peptides.

This study reports development of a microfluidic device for highly sensitive and selective detection of a β-amyloid peptide (Aβ1-42) in simulated cerebrospinal fluid, using surface-enhanced Raman spectroscopy (SERS). The device ensemble comprises a purine ligand (Pu) and its interaction with silver nanoparticles (AgNPs) to generate SERS hotspots. The low surface energy of the synthesized Pu ligand and high surface energy of AgNPs are utilized for the functionalization and formation of a Pu-AgNP SERS substrate. We have integrated a novel polydimethylsiloxane (PDMS) microfluidic device with Pu-AgNPs using a combination of photo- and soft lithography fabrication, sealed by thermal cross-linking with another layer of PDMS, to produce an effective screening platform for Aβ1-42. The SERS spectrum from the microfluidic device affords almost noise-free measurements, with excellent limit-of-detection values.

Highly sensitive and rapid detection of Vibrio parahaemolyticus using a dual-recognition platform based on functionalized quantum dots and aptamer.

As one of the most harmful pathogenic bacteria in shrimp aquaculture, Vibrio parahaemolyticus often causes massive mortality in shrimp. Accurate and rapid detection of V. parahaemolyticus in shrimp farming is essential for avoiding huge economic losses caused by related diseases. In this study, we designed a dual-recognition platform for efficient identification and quantification of V. parahaemolyticus. First, the target bacterium was captured with magnetic beads functionalized by aptamers (Apt-MBs), and then, the broad-spectrum fluorescent probe FcMBL@CdSe-ZnS was used to detect the bacterium based on the interactions between fragment crystallizable mannose-binding lectin (FcMBL) and pathogenic bacteria. The proposed dual-recognition strategy centered around aptamers and FcMBL@CdSe-ZnS was applied to definite quantification of V. parahaemolyticus over a wide range of 10-108 CFU/mL with a limit of detection of 4 CFU/mL within 55 min. The feasibility was demonstrated by using the platform to detect V. parahaemolyticus from shrimp intestine, aquaculture water, and seawater.

CRISPR-Cas12a-regulated DNA adsorption on MoS2 quantum dots: Enhanced enzyme mimics for sensitive colorimetric detection of human monkeypox virus and human papillomavirus DNA

Diseases caused by viruses, such as monkeypox virus (MPXV) and human papillomavirus (HPV), pose serious threats to human health and safety. Although numerous strategies have been constructed for detecting MPXV and HPV DNA, most methods require either laborious procedures or complicated instruments involving skilled professionals. In this research, a CRISPR-Cas12a-mediated colorimetric detection platform for MPXV and HPV sensing was constructed for the first time by applying probe DNA to reprogram the catalytic properties of molybdenum disulfide quantum dots (MoS2 QDs). In the presence of MPXV or HPV targets, the CRISPR-Cas12a trans-cleavage activity is effectively motivated to decompose the probe DNA, leading to the suppression of enzymatic activity DNA enhancer adsorbed on MoS2 QDs, resulting in greatly decreased catalytic behaviors. The MoS2 QDs-DNA nanohybrids displayed prominent specificity and sensitivity, with detection limits at subpicomolar levels, as well as excellent stability and accuracy for determining MPXV and HPV DNA in human sera biosamples. Furthermore, the proposed colorimetric biosensing approach can be ensembled with a smartphone platform, allowing visible analysis of DNA targets. Taken together, this colorimetric strategy offers a novel diagnosis method for MPXV and HPV DNA detection, particularly favorable for highly endemic developing countries with restricted medical and instrumental support.

Full on-device manipulation of olefin metathesis for precise manufacturing.

Olefin metathesis, as a powerful metal-catalysed carbon-carbon bond-forming method, has achieved considerable progress in recent years. However, the complexity originating from multicomponent interactions has long impeded a complete mechanistic understanding of olefin metathesis, which hampers further optimization of the reaction. Here, we clarify both productive and hidden degenerate pathways of ring-closing metathesis by focusing on one individual catalyst, using a sensitive single-molecule electrical detection platform. In addition to visualizing the full pathway, we found that the conventionally unwanted degenerate pathways have an unexpected constructive coupling effect on the productive pathway, and both types of pathway can be regulated by an external electric field. We then pushed forward this ability to ring-opening metathesis polymerization involving more interactive components. With single-monomer-insertion-event resolution, precise on-device synthesis of a single polymer was achieved by online manipulation of monomer insertion dynamics, intramolecular chain transfer, stereoregularity, degree of polymerization and block copolymerization. These results offer a comprehensive mechanistic understanding of olefin metathesis, exemplifying infinite opportunities for practical precise manufacturing.

Sensitive Detection of Gynecological Cancer Recurrence Using Circulating Tumor DNA and Digital PCR: A Comparative Study with Serum Biochemical Markers

Early detection of recurrences in gynecological cancers is crucial for women’s health. Circulating tumor DNA (ctDNA) analysis through liquid biopsy offers a promising approach for monitoring disease progression and identifying relapses. This study investigated the utility of digital Polymerase Chain Reaction (dPCR) for ctDNA detection in three gynecological cancer patients with clinically confirmed relapses during a two-year post-surgical follow-up. Patient-specific tumor mutations were identified through whole-exome sequencing (WES) and confirmed via Sanger sequencing. dPCR probes targeting these mutations were used to quantify the ctDNA levels in plasma samples collected throughout the follow-up period, and the findings were compared with standard serum biochemical markers. In two patients, persistent positive dPCR signals for the selected mutations were detected after tumor removal, with ctDNA levels progressively increasing even after post-surgical chemotherapy. Notably, dPCR identified elevated ctDNA levels before an increase in the cancer antigen 125 (CA125) biochemical marker was observed. In the third patient, no ctDNA signals from the two selected mutations were detected despite clinical evidence of recurrence, suggesting the emergence of new mutations. While this study highlights the promise of dPCR for early recurrence detection in gynecological cancers, it also underscores the critical need for comprehensive mutation panels to overcome the inherent challenges posed by tumor heterogeneity and the emergence of new mutations during disease progression.

Locking-Fluorescence Signals Regulated CRISPR/Cas12a Biosensor Based on Metal-Organic Framework for Sensitive Detection of Salmonella typhimurium.

The efficient, sensitive, and rapid detection of Salmonella typhimurium (S. typhimurium) in food and food products is important to ensure food safety and health. This study developed a fluorescence biosensing assay that integrated recombinase-aided amplification (RAA) and CRISPR/Cas12a with a zeolitic imidazolate framework-8@fluorescein sodium (ZIF-8@FLS) nanocomposite for the sensitive detection of S. typhimurium. In this approach, using RAA as a preamplification module, CRISPR/Cas12a-AChE as a target recognition and dual-enzyme cascade amplification module, and the prepared ZIF-8@FLS with high porosity and rapid pH responsiveness as a fluorescence signal explosive amplification module, the RAA-CRISPR/Cas12a-ZIF-8@FLS biosensor was constructed. Under optimal conditions, it exhibited an excellent linear relationship for S. Typhimurium, with a sensitive detection limit as low as 1.3 × 102 CFU/mL and could complete sample detection within 2 h relying on the RAA and ZIF-8@FLS explosive fluorescence rapid response, demonstrating its significant advantages in specificity, sensitivity, and reliability in food-borne pathogens detection.

DNA Nanomaterial-Based Electrochemical Biosensors for Clinical Diagnosis.

Sensitive and quantitative detection of chemical and biological molecules for screening, diagnosis and monitoring diseases is essential to treatment planning and response monitoring. Electrochemical biosensors are fast, sensitive, and easy to miniaturize, which has led to rapid development in clinical diagnosis. Benefiting from their excellent molecular recognition ability and high programmability, DNA nanomaterials could overcome the Debye length of electrochemical biosensors by simple molecular design and are well suited as recognition elements for electrochemical biosensors. Therefore, to enhance the sensitivity and specificity of electrochemical biosensors, significant progress has been made in recent years by optimizing the DNA nanomaterials design. Here, the establishment of electrochemical sensing strategies based on DNA nanomaterials is reviewed in detail. First, the structural design of DNA nanomaterial is examined to enhance the sensitivity of electrochemical biosensors by improving recognition and overcoming Debye length. In addition, the strategies of electrical signal transduction and signal amplification based on DNA nanomaterials are reviewed, and the applications of DNA nanomaterial-based electrochemical biosensors and integrated devices in clinical diagnosis are further summarized. Finally, the main opportunities and challenges of DNA nanomaterial-based electrochemical biosensors in detecting disease biomarkers are presented in an aim to guide the design of DNA nanomaterial-based electrochemical devices with high sensitivity and specificity.

Long-wavelength red-emitting ClO− fluorescent probe for visualizing inflammation and drug-induced renal injury

Hypochlorous acid (ClO−), a member of the reactive oxygen species (ROS) family, plays an important role in regulating physiological processes and maintaining homeostasis in the body. However, abnormal ClO− levels in the human body have been associated with a variety of pathological conditions, encompassing inflammation and kidney diseases. In this work, we have developed a novel fluorescent probe, RDNClO, specifically tailored for the sensitive detection of ClO−. RDNClO was synthesized through modifying N - (7 - (2 - carboxyphenyl) -3- (dimethylamino) - 5,6 - dihydro - 10H - benzo[c]xanthen - 10 - ylidene) - N - ethylethanaminium (RDNOH) with 1-naphthaloyl chloride moiety. Spectroscopic analyses reveal that RDNClO exhibits outstanding performance characteristics, including high selectivity, a rapid response time of <25 s, and an ultra-low detection limit of 3.7 nM. Additionally, RDNClO has demonstrated exceptional capabilities in detecting ClO− in real water samples and rapidly identifying ClO− in environmental samples, utilizing agarose as a carrier. It effectively monitors both endogenous ClO− levels in HeLa cells and exogenous ClO− levels in HEK293T cells. Furthermore, RDNClO has excelled in tracking fluctuations in ClO− levels, including in Escherichia coli, the mouse model of arthritis induced by k-carrageenan, and a mouse model of cisplatin-induced renal injury. The development of RDNClO not only establishes a robust theoretical foundation for investigating the pathogenic mechanisms of renal injury but also presents a promising tool for advancing research in this critical area.

Polarization modulated spectroscopic ellipsometry-based surface plasmon resonance biosensor for E. coli K12 detection

In this work, we report on the application of the polarization modulated spectroscopic ellipsometry-based surface plasmon resonance method for sensitive detection of microorganisms in Kretschmann configuration. So far, rotating analyzer and single wavelength polarization modulation methods have widely been investigated for phase sensitive surface plasmon resonance measurement. In this study, a much simpler optical setup relying on fast electro-optic phase modulator crystals is introduced for bacteria detection. A beta barium borate crystal connected to a function generator is adapted for generating phase shifts in the millisecond regime to extract the ellipsometric angles (Ψ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\Psi$$\\end{document} and Δ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\Delta$$\\end{document}) under the surface plasmon resonance condition. For detection, the gold surface was functionalized with anti-Escherichia coli antibodies, and E. coli K12 was attached to them. We show that polarization modulated spectroscopic ellipsometry achieves a refractive index resolution in the order of 10-5\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$10^{-5}$$\\end{document} RIU, and a limit of detection of 102\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$10^{2}$$\\end{document} CFU/mL for E. coli K12 which is compatible with other surface plasmon resonance based phase sensitive methods with more complex detection concepts. As a follow-up step, an optical model can be developed to enhance this biosensor’s performance, and applications for sorting and detecting other biological targets will be investigated.

Chain extension-mediated colorimetric and sensitive detection of osteosarcoma-related miRNA based on CHA-cooperated self-priming

The accurate and dynamic monitoring of osteosarcoma, one of the most prevalent cancers, has a substantial impact on the quality of life of numerous individuals. This study proposes a sample, sensitive, and portable approach to miRNA detection that integrates a catalytic hairpin assembly (CHA) circuit with self-priming mediated chain extension. This method employs CHA as a protein enzyme-free isothermal amplification technique to amplify miRNA signals and induce self-priming through a specially designed hairpin probe. The pyrophosphate sensing probe (pp probe) was employed, which enables dual high-efficiency and stable colorimetric signaling, in contrast to traditional colorimetric modes. This novel system for the colorimetric detection of target miRNA is operated with high sensitivity (LOD of 3.5 fM) and selectivity, with the entire detection procedure requiring approximately 60 min. Additionally, this system could detect miRNA from constructed serum samples with high stability and recovery. This system is unique, extremely simple, and rapid, and it is designed to detect osteosarcoma-related miRNA through a highly sensitive color change. It is likely to be useful in applications that necessitate point-of-care detection of osteosarcoma.

A flexible plasmonic substrate for sensitive surface-enhanced Raman scattering-based detection of fentanyl.

In this work, we demonstrate a straightforward and versatile approach for fabricating flexible SERS substrates for highly sensitive fentanyl detection. Our design strategy integrates the synthesis of a yolk-shell structured plasmonic nanomaterial with a flexible cellulose substrate. The resulting SERS platform demonstrates excellent sensing capabilities, achieving a fentanyl detection limit as low as 4.89 ng mL-1.

TtAgo-coupled-multiplex-digtal-RPA-CRISPR/Cas12a (TCMDC) for EGFR mutations detection

Epidermal Growth Factor Receptor (EGFR) is an important target for the early evaluation, treatment, and postoperative follow-up in non-small cell lung cancer (NSCLC). Current detection technologies suffer from extended detection time and high rate of false positive amplification. Therefore, the development of rapid, highly sensitive and specific detection methods is of great significance for improving the diagnosis and treatment of lung cancer. In this study, we proposed a fast and sensitive detection method termed Thermus thermophilus Argonaute (Ttago)-Coupled-Multiplex-digital-recombinase polymerase amplification (RPA)-Clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a (TCMDC) detection method, integrating EGFR mutation template enrichment. Based on the cleavage principle of TtAgo, the wild type (WT) template was enriched under the action of double-guide DNA. Two CRISPR RNAs, not restricted by protospacer adjacent motif (PAM) sites, were introduced to target EGFR genes. By combining RPA with CRISPR-Cas12a, we established a single-pot, ultra-sensitive (1 copy, 0.1 %), and visually detectable method for EGFR detection. We further verified the feasibility of this approach using clinical serum samples from lung cancer patients, achieving rapid (within 1 h) and visual detection of EGFR, thereby presenting a promising clinical tool for the detection of lung cancer.

CRISPR-Cas14a and allosteric transcription factors empowered cell-free electrochemical biosensor for highly sensitive and stable detection of progesterone in multiple scenarios

In this study, a cell-free electrochemical assay based on allosteric transcription factors (aTFs) and CRISPR-Cas14a was developed for the detection of progesterone in trace samples. This electrochemical biosensor helps to overcome the drawbacks of the traditional fluorescence assay based on the CRISPR-Cas system and aTFs combined for non-nucleic acid targets that is poorly effective for the detection of colored samples. By comparing and optimizing the concentration and length of the probes in the straight chain and hairpin structure, the sensor performance was improved. In addition, different sgRNA from other studies was designed to overcome the effect of sequence folding in the space region on Cas14a activation. Based on these optimization results, we constructed an electrochemical sensor for progesterone quantification in the range of 66.7pM to 3.33 × 10−1μM. This method requires only 2 μL of sample and does not necessitate complex pretreatment steps, with detection completed within 1.5 h. The method has been successfully applied to food, environmental, and biological samples, with recovery rates between 82.65% and 109%. This suggests that CRISPR and allosteric transcription factor-powered electrochemical detection methods have significant potential for use in the field of small molecule detection under various scenarios.

Nanowire-like phosphorus modulated carbon-based iron nanozyme with oxidase-like activity for sensitive detection of choline and dye degradation

Choline is mainly supplemented through food intake, lack of choline would result in diseases like liver cirrhosis, hardening of the arteries, or neurodegenerative disorders. The accurate detection of choline is important for human health. Herein, a novel nanowire-like phosphorus/nitrogen co-doped carbon-based iron nanozyme (Fe-NPC) with outstanding oxidase-like activity was synthesized, and the influence of phosphorus doping on oxidase-like activity was explored. Proper phosphorus doping was found to enhance the oxidase-like activity of Fe-NPC by increasing surface defects, promoting iron loading, and modulating chemical environment of central site. The oxidase-like activity of Fe-NPC was successfully applied to colorimetric-fluorescent dual mode detection of choline, and good linear relationship in the ranges of 3–200 μM were achieved with LODs of 1.95 and 1.50 μM, respectively. The fluorescent detection was constructed based on the fluorescence quenching of silicon quantum dots (Si QDs) by quinone-imine. The quenching mechanism was attributed to FRET due to the large spectra overlap, reduced fluorescence lifetime and proper donor−acceptor distance. The successful application to the detection of choline in milk proved the practicability of the proposed sensing method. The oxidase-like properties of Fe-NPC was further used in the degradation of cationic dye methyl blue, high degradation efficiency of 74 % was achieved within 5 min under optimal conditions, proving the enormous potential of Fe-NPC for application in environment protection.

Hexagonal Morphology Nickel Sulfide Anchored on Graphene Oxide–Modified Glassy Carbon Electrode for the Sensitive Detection of Paracetamol in Biological Samples

Hexagonal Morphology Nickel Sulfide Anchored on Graphene Oxide–Modified Glassy Carbon Electrode for the Sensitive Detection of Paracetamol in Biological Samples