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1.
J Hazard Mater ; 475: 134908, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38889459

ABSTRACT

Previous research has established a MES embedding a microbial electrode to facilitate the degradation of antibiotics in water. We modified microbial electrodes in the MES with PEDOT and rGO to enhance electron utilization on electrodes and to further promote antibiotic degradation. Density functional theory calculations on the SMX molecule indicated that the C4-S8 and S8-N27 bonds are the most susceptible to electron attack. The introduction of various functional groups and multivalent elements enhanced the electrodes' capacitance and electron mediation capabilities. This led to enhance both electron utilization on the electrodes and the removal efficiency of SMX. After 120 h, the degradation efficiency of SMX by PEDOT and rGO-modified electrodes increased by 45.47 % and 25.19 %, respectively, compared to unmodified electrodes. The relative abundance of sulfate-reducing and denitrifying bacteria significantly increased in PEDOT and rGO-modified electrodes, while the abundance of nitrifying bacteria and potential antibiotic resistance gene host microbes significantly decreased. The impact of PEDOT modification positively influenced microbial Cellular Processes, including cell growth, death, and motility. This study provides insights into the mechanisms of direct electron involvement in antibiotic degradation steps in microbial electrochemistry, and provides a possible path for improved strategies in antibiotic degradation and sustainable environmental remediation.


Subject(s)
Anti-Bacterial Agents , Electrodes , Electrons , Polymers , Anti-Bacterial Agents/chemistry , Polymers/chemistry , Bacteria/metabolism , Bacteria/genetics , Graphite/chemistry , Bridged Bicyclo Compounds, Heterocyclic/chemistry , Electrochemical Techniques , Water Pollutants, Chemical/chemistry
2.
J Med Chem ; 67(12): 10035-10056, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38885173

ABSTRACT

Triple-negative breast cancer (TNBC) represents a highly aggressive and heterogeneous malignancy. Currently, effective therapies for TNBC are very limited and remain a significant unmet clinical need. Targeting the transcription-regulating cyclin-dependent kinase 9 (CDK9) has emerged as a promising avenue for therapeutic treatment of TNBC. Herein, we report the design, synthesis, optimization, and evaluation of a new series of aminopyrazolotriazine compounds as orally bioavailable, potent, and CDK9/2 selectivity-improved inhibitors, enabling efficacious inhibition of TNBC cell growth, as well as notable antitumor effect in TNBC models. The compound C35 demonstrated low-nanomolar potency with substantially improved CDK9/2 selectivity, downregulated the CDK9-downstream targets (e.g., MCL-1), and induced apoptosis in TNBC cell lines. Moreover, with the desired oral bioavailability, oral administration of C35 could significantly suppress the tumor progression in two TNBC mouse models. This study demonstrates that target transcriptional regulation is an effective strategy and holds promising potential as a targeted therapy for the treatment of TNBC.


Subject(s)
Antineoplastic Agents , Cyclin-Dependent Kinase 9 , Protein Kinase Inhibitors , Triple Negative Breast Neoplasms , Cyclin-Dependent Kinase 9/antagonists & inhibitors , Cyclin-Dependent Kinase 9/metabolism , Triple Negative Breast Neoplasms/drug therapy , Triple Negative Breast Neoplasms/pathology , Humans , Animals , Female , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/chemistry , Antineoplastic Agents/chemical synthesis , Administration, Oral , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , Protein Kinase Inhibitors/pharmacokinetics , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/chemical synthesis , Mice , Cell Line, Tumor , Structure-Activity Relationship , Biological Availability , Cell Proliferation/drug effects , Apoptosis/drug effects , Drug Discovery , Transcription, Genetic/drug effects , Mice, Nude , Xenograft Model Antitumor Assays
3.
Talanta ; 276: 126209, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38728802

ABSTRACT

The rapid development of nanozymes has offered substantial opportunities for the fields of biomedicine, chemical sensing, and food safety. Among these applications, multichannel sensors, with the capability of simultaneously detecting multiple target analytes, hold promise for the practical application of nanozymes in chemical sensing with high detection efficiency. In this study, Rh-decorated Pd nanocubes (Pd-Rh nanocubes) with significantly enhanced peroxidase-like activity are synthesized through the mediation of underpotential deposition (UPD) and subsequently employed to develop a multichannel colorimetric sensor for discriminating tea polyphenols (TPs) and tea authentication. Based on a single reactive unit of efficient catalytic oxidation of 3,3',5,5'-tetramethylbenzidine dihydrochloride (TMB), the nanozyme-based multichannel colorimetric sensor responds to each analyte in as short as 1 min. With the aid of principal component analysis (PCA) and hierarchical cluster analysis (HCA), various TPs and types of tea can be accurately identified. This work not only provides a new type of simply structured and highly active nanozymes but also develops a concise and rapid multichannel sensor for practical application in tea authentication and quality inspection.


Subject(s)
Colorimetry , Palladium , Polyphenols , Tea , Tea/chemistry , Polyphenols/analysis , Polyphenols/chemistry , Colorimetry/methods , Palladium/chemistry , Benzidines/chemistry , Metal Nanoparticles/chemistry , Principal Component Analysis , Peroxidase/chemistry , Catalysis , Oxidation-Reduction
4.
RSC Adv ; 14(25): 17491-17497, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38818364

ABSTRACT

A dual-signal optical sensing platform was successfully developed for the determination of ascorbic acid (AA) based on blue fluorescent carbon dots (CDs) and manganese dioxide nanosheets (MnO2 NSs) with strong Tyndall effect (TE) scattering and fluorescence quenching capabilities. In this nanosystem, CDs-MnO2 NS composites were employed as probes to evaluate the AA concentration. Owing to the strong reduction, the presence of the target AA could reduce the MnO2 NSs to Mn2+ and induce the degradation of the MnO2 NSs, resulting in a significant decrease in the TE scattering intensity of the MnO2 NSs and the fluorescence recovery of the CDs. Therefore, a novel optical sensor based on TE scattering and fluorescence dual detectors was developed for the sensitive determination of AA. Under optimized conditions, the limits of detection (LODs) of the two modes were 113 and 3 nM, respectively. Furthermore, the dual-signal optical sensing platform was successfully applied for the detection of AA in human serum.

5.
Biosens Bioelectron ; 259: 116402, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38788342

ABSTRACT

In this work, a high-performance conjugated microporous polymer (CMP) decorated with BiOBr (Tr(PhXOD)3-CMP/BiOBr) is synthesized to application in construction of ultrasensitive photoelectrochemical (PEC) biosensor for sensing miRNA-122, by firstly coupling with efficient clip toehold-mediated allosteric bicycle strand displacement (ABSD). Notably, the Tr(PhXOD)3-CMP/BiOBr not only owns self-enhanced D-A-D structure that extremely shortens migration distance of photo-generated electron, but also forms Z-type heterostructure for accelerating electron-hole separation, thereby significantly enhancing the photocurrent with 10-fold higher than commonly used methods. Meanwhile, the clip toehold-mediated ABSD based on ternary linkage structure transformation avoids the attrition of invading strand, endowing the conservation of high concentration for undergoing rapid reaction with high-efficiency DNA amplification, which dramatically improves reaction time and superior target conversion. The experimental results indicate that proposed PEC biosensor had a high sensitivity to miRNA-122 with a detection limit of 0.49 fM, which provides a newly organic/inorganic photosensitive nanomaterials and efficient DNA strand displacement in bioanalytical and early clinical disease diagnosis.


Subject(s)
Biosensing Techniques , Limit of Detection , MicroRNAs , Polymers , Biosensing Techniques/methods , Polymers/chemistry , MicroRNAs/analysis , Electrochemical Techniques/methods , Humans , DNA/chemistry
6.
Int Immunopharmacol ; 131: 111833, 2024 Apr 20.
Article in English | MEDLINE | ID: mdl-38503012

ABSTRACT

Nonalcoholic steatohepatitis (NASH), an inflammatory subtype of nonalcoholic fatty liver disease (NAFLD), is characterized by liver steatosis, inflammation, hepatocellular injury and different degrees of fibrosis, and has been becoming the leading cause of liver-related morbidity and mortality worldwide. Unfortunately, the pathogenesis of NASH has not been completely clarified, and there are no approved therapeutic drugs. Recent accumulated evidences have revealed the involvement of macrophage in the regulation of host liver steatosis, inflammation and fibrosis, and different phenotypes of macrophages have different metabolic characteristics. Therefore, targeted regulation of macrophage immunometabolism may contribute to the treatment and prognosis of NASH. In this review, we summarized the current evidences of the role of macrophage immunometabolism in NASH, especially focused on the related function conversion, as well as the strategies to promote its polarization balance in the liver, and hold promise for macrophage immunometabolism-targeted therapies in the treatment of NASH.


Subject(s)
Non-alcoholic Fatty Liver Disease , Humans , Non-alcoholic Fatty Liver Disease/drug therapy , Liver/pathology , Inflammation/metabolism , Fibrosis , Macrophages/metabolism
7.
J Pharm Biomed Anal ; 243: 116083, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38447348

ABSTRACT

Daratumumab, a humanized monoclonal antibody utilized in treating immunoglobulin light-chain amyloidosis and relapsed/refractory multiple myeloma, was quantified in rat serum through a simple, economical and effective liquid chromatography tandem-mass spectrometry (LC-MS/MS) method. A surrogate peptide, LLIYDASNR, derived from trypsin hydrolysis, was quantitatively analyzed with LLIYDASN [13C6, 15N4] RAT as an internal standard. This corrected variations from sample pretreatment and mass spectrometry response, involving denaturation and trypsin hydrolysis in a two-step process lasting approximately 1 hour. Methodological validation demonstrated a linear range of 1 µg/mL to 1000 µg/mL in rat serum. Precision, accuracy, matrix effect, sensitivity, stability, selectivity, carryover, and interference met acceptance criteria. The validated LC-MS/MS approach was successfully applied to a pharmacokinetic study of daratumumab in rats at an intravenous dose of 15 mg/kg.


Subject(s)
Liquid Chromatography-Mass Spectrometry , Tandem Mass Spectrometry , Chromatography, Liquid/methods , Trypsin , Tandem Mass Spectrometry/methods , Antibodies, Monoclonal/chemistry , Immunoglobulin G , Digestion , Reproducibility of Results
8.
Biosens Bioelectron ; 250: 116081, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38316088

ABSTRACT

In this work, a novel covalent organic frame (TAPT-TFPB COF) with self-enhanced photoelectric activity was prepared for decorating on conductive single-walled carbon nanotubes (SWCNT) to synthetize a high-performance photoelectric nanocomposite (COF/SWCNT), in which the interfacial charge separation and photogenerated carrier migration rate was significantly improved to obtain desiring photoelectric conversion efficiency for generating an extremely high photocurrent. Accordingly, the synthetic COF/SWCNT was ingeniously applied in the fabrication of ultrasensitive photoelectrochemical (PEC) biosensor for realizing the trace ATP detection by integrating with an Exo III-assisted dual DNA recycling amplification strategy. The recycling amplification could efficiently convert trace target ATP into plentiful output DNA, which ingeniously triggered the hybridization chain reaction (HCR) to generate a long DNA strand with substantial quencher manganese porphyrin (MnPP) loading to depress the photocurrent of COF/SWCNT. The experimental data showed that proposed biosensor had a detection range from 10 fmol L-1 to 10 nmol L-1 with the detection limit as low as 2.75 fmol L-1 (S/N = 3). In addition, this proposed biosensor showed excellent analytical performance in terms of stability, specificity and reproducibility, providing a possibility to accomplish sensitive and accurate in vitro diagnosis.


Subject(s)
Biosensing Techniques , Nanocomposites , Nanotubes, Carbon , Reproducibility of Results , DNA , Adenosine Triphosphate , Electrochemical Techniques , Limit of Detection
9.
Anal Bioanal Chem ; 416(8): 1821-1832, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38363308

ABSTRACT

This paper describes initially the application of the Tyndall effect (TE) of metal-organic framework (MOF) materials as a colorimetric signaling strategy for the sensitive detection of pyrophosphate ion (PPi). The used MOF NH2-MIL-101(Fe) was prepared with Fe3+ ions and fluorescent ligands of 2-amino terephthalic acid (NH2-BDC). The fluorescence of NH2-BDC in MOF is quenched due to the ligand-to-metal charge transfer effect, while the NH2-MIL-101(Fe) suspension shows a strong TE. In the presence of PPi analyte, the MOFs will undergo decomposition because of the competitive binding of Fe3+ by PPi over NH2-BDC, resulting in a significant decrease in the TE signal and fluorescence restoration from the released ligands. The results demonstrate that the new method only requires a laser pointer pen (for TE creation) and a smartphone (for portable quantitative readout) to detect PPi in a linear concentration range of 1.25-800 µM, with a detection limit of ~210 nM (3σ) which is ~38 times lower than that obtained from traditional fluorescence with a spectrophotometer (linear concentration range, 50-800 µM; detection limit, 8.15 µM). Moreover, the acceptable recovery of PPi in several real samples (i.e., pond water, black tea, and human serum and urine) ranges from 97.66 to 119.15%.


Subject(s)
Metal-Organic Frameworks , Humans , Metal-Organic Frameworks/chemistry , Colorimetry/methods , Diphosphates/chemistry , Amino Acids
10.
J Pharm Biomed Anal ; 242: 116012, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38354539

ABSTRACT

Linaprazan (AZD0865, TX07) is one of potassium-competitive acid blockers. However, linaprazan is rapidly excreted from the body, shortening its acid inhibition property. Linaprazan glurate (X842) is a prodrug of linaprazan with a prolonged inhibitory effect on gastric acid secretion. Linaprazan glurate has entered clinical trials, but few studies have reported its metabolism in non-clinical and clinical settings. In this study, we studied the pharmacokinetics, tissue distribution, mass balance, and metabolism of linaprazan glurate in rats after a single oral dose of 2.4 mg/kg (100 µCi/kg) [14C]linaprazan glurate. The results demonstrated that linaprazan glurate was mainly excreted via feces in rats with 70.48% of the dose over 168 h. The plasma AUC0-∞ of linaprazan glurate in female rats was 2 times higher than that in male rats. Drug-related substances were mainly concentrated in the stomach, eyes, liver, small intestine, and large intestine after administration. In blood, drug-related substances were mostly distributed into plasma instead of hemocytes. In total, 13 metabolites were detected in rat plasma, urine, feces, and bile. M150 (2,6-dimethylbenzoic acid) was the predominant metabolite in plasma, accounting for 80.65% and 67.65% of AUC0-24h in male and female rats, respectively. Based on the structures, linaprazan glurate was mainly hydrolyzed into linaprazan, followed by a series of oxidation, dehydrogenation, and glucuronidation in rats. Besides, CES2 is the main metabolic enzyme involved in the hydrolysis of linaprazan glurate to linaprazan.


Subject(s)
Body Fluids , Heterocyclic Compounds, 2-Ring , Rats , Male , Female , Animals , Feces/chemistry , Bile/metabolism , Plasma , Administration, Oral
11.
Article in English | MEDLINE | ID: mdl-38266611

ABSTRACT

A new liquid chromatography tandem mass spectrometry (LC-MS/MS) method was established to quantify the anti-gastric cancer fully human monoclonal antibody (ramucirumab) in rat and human serum. The surrogate peptide (GPSVLPLAPSSK) for ramucirumab was generated by trypsin hydrolysis and quantified using the isotopically labeled peptide GPSVLPLAPSSK[13C6, 15N2]ST containing two more amino acids at the carboxyl end as an internal standard to correct for variations introduced during the enzymatic hydrolysis process and any mass spectrometry changes. Additionally, the oxidation and deamidation of unstable peptides (VVSVLTVLHQDWLNGK and NSLYLQMNSLR) were detected. The quantitative range of the proposed method was 1-1000 µg/mL, and complete methodological validation was performed. The precision, accuracy, matrix effect, sensitivity, stability, selectivity, carryover, and interference of the measurements met the required standards. The validated LC-MS/MS method was applied to pharmacokinetic studies in rats administered ramucirumab at 15 mg/kg intravenously. Overall, a robust, efficient, and cost-effective LC-MS/MS method was successfully developed for quantifying ramucirumab in rat and human serum.


Subject(s)
Ramucirumab , Tandem Mass Spectrometry , Humans , Rats , Animals , Chromatography, Liquid/methods , Tandem Mass Spectrometry/methods , Liquid Chromatography-Mass Spectrometry , Peptides/chemistry , Immunoassay , Digestion , Reproducibility of Results
12.
Small ; 20(3): e2305369, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37679094

ABSTRACT

The growing demand for highly active nanozymes in various fields has led to the development of several strategies to enhance their activity. Plasmonic enhancement, a strategy used in heterogenous catalysis, represents a promising strategy to boost the activity of nanozymes. Herein, Pd-Au heteromeric nanoparticles (Pd-Au dimers) with well-defined heterointerfaces have been explored as plasmonic nanozymes. As a model system, the Pd-Au dimers with integrated peroxidase (POD)-like activity and plasmonic activity are used to investigate the effect of plasmons on enhancing the activity of nanozymes under visible light irradiation. Mechanistic studies revealed that the generation of hot electron-hole pairs plays a dominant role in plasmonic effect, and it greatly enhances the decomposition of H2 O2 to the reactive oxygen species (ROS) intermediates (•OH, •O2 - and 1 O2 ), leading to elevated POD-like activity of the Pd-Au dimers. Finally, the Pd-Au dimers are applied in the plasmon-enhanced colorimetric method for the detection of alkaline phosphatase, exhibiting broad linear range and low detection limit. This study not only provides a straightforward approach for regulating nanozyme activity through plasmonic heterostructures but also sheds light on the mechanism of plasmon-enhanced catalysis of nanozymes.


Subject(s)
Colorimetry , Nanoparticles , Colorimetry/methods , Catalysis , Reactive Oxygen Species
13.
Xenobiotica ; 54(1): 1-9, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38044881

ABSTRACT

LN005 is a peptide-drug conjugate (PDC) targeting glucose-regulated protein 78 (GRP78) to treat several types of cancer, such as breast, colon, and prostate cancer.As a new drug modality, understanding its metabolism and elimination pathways will help us to have a whole picture of it. Currently, there are no metabolic studies on LN005; therefore, this study aimed to investigate the metabolism of LN005, clarify its metabolic profile in the liver S9s of different species, and identify the major metabolic pathways and differences between species.The incubation samples were measured by ultra-high performance liquid chromatography combined with orbitrap tandem mass spectrometry (UHPLC-Orbitrap-HRMS).The results showed that LN005 was metabolised by liver S9s, and four metabolites were identified. The main metabolic pathway of LN005 in liver S9s was oxidative deamination to ketone or hydrolysis. Similar metabolic profiles were observed in mouse, rat, dog, monkey, and human liver S9s, indicating no differences between these four animal species and humans.This study provides information for the structural modification and optimisation of LN005 and affords a reference for subsequent animal experiments and human metabolism of other PDCs.


Subject(s)
Liver , Microsomes, Liver , Male , Rats , Mice , Humans , Animals , Dogs , Microsomes, Liver/metabolism , Chromatography, High Pressure Liquid/methods , Tandem Mass Spectrometry/methods , Peptides/metabolism , Haplorhini
14.
Nanoscale ; 15(46): 18901-18909, 2023 Nov 30.
Article in English | MEDLINE | ID: mdl-37975296

ABSTRACT

The application of surface plasmons in heterogeneous catalysis has attracted widespread attention due to their promising potential for harvesting solar energy. The effect of surface adsorbates on catalysts has been well documented in many traditional reactions; nonetheless, their role in plasmonic catalysis has been rarely studied. In this study, an in situ electrochemical surface cleaning strategy is developed and the influence of surface adsorbates on plasmon-enhanced electrochemistry is investigated. Taking Au nanocubes as an example, plasmonic catalysts with clean surfaces are obtained by Cu2O coating and in situ electrochemical etching. During this process, the surface adsorbates of Au nanocubes are removed together with the Cu2O shells. The Au nanocubes with clean surfaces exhibit remarkable performance in plasmon-enhanced electrooxidation of glucose and an enhancement of 445% is demonstrated. The Au NCs with clean surfaces can not only provide more active sites but also avoid halides as hole scavengers, and therefore, the efficient utilization of hot holes by plasmonic excitation is achieved. This process is also generalized to other molecules and applied in electrochemical sensing with high sensitivity. These results highlight the critical role of surface adsorbates in plasmonic catalysis and may forward the design of efficient plasmonic catalysts for plasmon-enhanced electrochemistry.

15.
Mikrochim Acta ; 190(12): 478, 2023 Nov 23.
Article in English | MEDLINE | ID: mdl-37993700

ABSTRACT

A dual-mode pH sensor based on nitrogen-doped carbon dots (N-CDs) with the source of o-phenylenediamine and tryptophan has been constructed. Under the stimulation of pH, the N-CDs exhibited prominent both color and fluorescence changes, leading to the rarely discovered colorimetric and fluorescent dual-readouts for the evaluation of pH. The mathematic relationship was established between pH and fluorescence intensity of N-CDs, and between pH and the UV-Vis absorbance ratio at 630 nm and 488 nm of N-CDs, respectively, over a quite broad pH range of 2.2 to 12.0. Multiple techniques are used to explore the dual-mode pH-responsive mechanism, and the preliminary explanation is put forward. The experimental results show that the N-CDs have visualized pH sensing applicability for actual samples, including various water samples and HeLa cell. Furthermore, the N-CD ink is developed for successful information encryption and anti-counterfeiting. This work might provide valuable insights into the sensing mechanism of CDs, and the application potential of CDs in broader fields.

16.
Anal Chem ; 95(45): 16625-16630, 2023 11 14.
Article in English | MEDLINE | ID: mdl-37908115

ABSTRACT

Herein, a novel photocathodic nanocomposite poly{4,8-bis[5-(2-ethylhexyl)-thiophen-2-yl] benzo[1,2-b:4,5-b']dithiophene-2,6-diyl-alt-3-fluoro-2-[(2-ethylhexyl)-carbonyl]thieno[3,4-b]thiophene-4,6-diyl}/phthalocyanine zinc (PTB7-Th/ZnPc) with high photoelectric conversion efficiency under long-wavelength illumination was prepared to construct an ultrasensitive biosensor for the detection of microRNA-21 (miRNA-21), accompanied by a prominent anti-interference capability toward reductive substances. Impressively, the new heterojunction PTB7-Th/ZnPc nanocomposite could not only generate a strong cathodic photocurrent to improve the detection sensitivity under long-wavelength illumination (660 nm) but also effectively avoid the high damage of biological activity caused by short-wavelength light stimulation. Accordingly, by coupling with rolling circle amplification (RCA)-triggered DNA amplification to form functional biquencher nanospheres, a PEC biosensor was fabricated to realize the ultrasensitive analysis of miRNA-21 in the concentration range of 0.1 fM to 10 nM with a detection limit as low as 32 aM. This strategy provided a novel long-wavelength illumination-induced photocurrent enhancement photoactive material for a sensitive and low-damage anti-interference bioassay and early clinical disease diagnosis.


Subject(s)
Biosensing Techniques , MicroRNAs , Nanocomposites , Lighting , Electrochemical Techniques , MicroRNAs/analysis
17.
Anal Chem ; 95(37): 13967-13974, 2023 09 19.
Article in English | MEDLINE | ID: mdl-37672686

ABSTRACT

Herein, we synthesized a novel porphyrinic covalent organic polymer (TPAPP-PTCA PCOP) for constructing a polarity-switchable dual-wavelength photoelectrochemical (PEC) biosensor with ferrocene (Fc) and hydrogen peroxide (H2O2) as regulator and amplifier simultaneously. Interestingly, this new PCOP possessed both n-type and p-type semiconductor characteristics, which thus enabled the appearance of a dual-polarity photocurrent at two different excitation wavelengths. Furthermore, Fc and H2O2 could readily switch the photocurrent of PCOP to the cathode and anode stemming from its efficient electron collection and donation function, respectively. Based on these, a PCOP-based PEC biosensor skillfully integrating dual wavelengths with reliable accuracy and polarity switch with high sensitivity was instituted. As a result, the developed PEC biosensor exhibited a low detection limit down to 0.089 pg mL-1 for the most powerful natural carcinogen aflatoxin M1 (AFM1) assay. Impressively, the target exhibited a completely opposite photocurrent difference to the interfering substances, and the linear correlation coefficient of the assay was improved compared to single-wavelength detection. The PEC sensing platform not only provided a basis for exploring multicharacteristic photoactive material but also innovatively developed the detection mode of the PEC biosensor.


Subject(s)
Aflatoxin M1 , Hydrogen Peroxide , Amplifiers, Electronic , Polymers
18.
Anal Chim Acta ; 1272: 341436, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37355318

ABSTRACT

Photocathodic biosensor possesses excellent anti-interference capability in bioanalysis, which however suffers from high electron-hole recombination rate with low photocurrent. Herein, a high-performance inorganic organic P3HT@C60@ZnO nanosphere with cascade energy band arrangement was synthesized as photoactive signal probe, which inherited the advantages of inorganic strong optical absorptivity and organic high mobility for photo-generated holes. Specifically, the well-matched band gap endowed not only the improved life for light generated carrier and promoted separation of electron-hole pairs, but also the expansion of charge-depletion layer, significantly improving the photoelectric conversion efficiency for acquiring an extremely high photocathodic signal that increased by 30 times compared with individual materials. Accordingly, by integrating with the efficient amplification of DNA nanonet derived from clamped hybrid chain reaction (C-HCR), a sensitive P3HT@C60@ZnO nanosphere based photocathodic biosensor was proposed for accurate detection of p53. The experimental results showed that the biosensor had a wide detection range from 0.1 fM to 10 nM and a low detection limit of 0.37 fM toward p53, offering a new avenue to construct sensitive PEC platform with superior anti-interference ability and hold a prospective application in early disease diagnosis and biological analysis.


Subject(s)
Biosensing Techniques , Zinc Oxide , Electrochemical Techniques , Tumor Suppressor Protein p53 , DNA/analysis , Biosensing Techniques/methods , Limit of Detection
19.
Biosensors (Basel) ; 13(5)2023 Apr 28.
Article in English | MEDLINE | ID: mdl-37232870

ABSTRACT

The efficacies and toxicities of chiral drug enantiomers are often dissimilar, necessitating chiral recognition methods. Herein, a polylysine-phenylalanine complex framework was used to prepare molecularly imprinted polymers (MIPs) as sensors with enhanced specific recognition capabilities for levo-lansoprazole. The properties of the MIP sensor were investigated using Fourier-transform infrared spectroscopy and electrochemical methods. The optimal sensor performance was achieved by applying self-assembly times of 30.0 and 25.0 min for the complex framework and levo-lansoprazole, respectively, eight electropolymerization cycles with o-phenylenediamine as the functional monomer, an elution time of 5.0 min using an ethanol/acetic acid/H2O mixture (2/3/8, V/V/V) as the eluent, and a rebound time of 10.0 min. A linear relationship was observed between the sensor response intensity (ΔI) and logarithm of the levo-lansoprazole concentration (l-g C) in the range of 1.0 × 10-13-3.0 × 10-11 mol/L. Compared with a conventional MIP sensor, the proposed sensor showed more efficient enantiomeric recognition, with high selectivity and specificity for levo-lansoprazole. The sensor was successfully applied to levo-lansoprazole detection in enteric-coated lansoprazole tablets, thus demonstrating its suitability for practical applications.


Subject(s)
Molecular Imprinting , Molecularly Imprinted Polymers , Phenylalanine , Polylysine , Polymers/chemistry , Molecular Imprinting/methods , Electrochemical Techniques/methods , Limit of Detection
20.
J Hazard Mater ; 457: 131724, 2023 09 05.
Article in English | MEDLINE | ID: mdl-37257386

ABSTRACT

Herein, we synthesized a conjugated microporous polymer (CMP) decorated C60 (CMP@C60) with high photoelectric conversion efficiency, in which continuously repeated donor-acceptor (D-A) π electron unit within one molecule of CMP on C60 could not only effectively increase the mobility of photogenerated carriers with improved electron transmission, but also constitute the cascade energy band matching with reduced electron-hole recombination. Based on the high-performance of CMP@C60 for producing exciting initial photoelectrochemical (PEC) signal, a sensitive signal-off sensing platform was designed for lead ion (Pb2+) assay by coupling with quencher methylene blue (MB) interacting on efficient long tailed Y-triangular DNA structure (LYTD). The proposed LYTD with a tripod structure could generate six long tails in situ on its side at the same time via a simple hybridization chain reaction (HCR), providing notably grooves on electrode to accommodate quencher MB to significantly depress the signal for sensitive detection of Pb2+. As a result, the proposed PEC biosensor revealed excellent analysis capability with a low detection limit of 0.3 fM (S/N = 3). Additionally, it also showed satisfactory stability in the detection of tap water samples, lake water samples and clinical serum samples, manifesting great application prospect in the areas of environmental pollutant detection.


Subject(s)
Biosensing Techniques , Lead , Electrochemical Techniques/methods , Limit of Detection , DNA/chemistry , Biosensing Techniques/methods , Methylene Blue/chemistry , Water , Polymers
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