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1.
Inorg Chem ; 63(21): 9753-9762, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38743025

ABSTRACT

Global warming and heavy metal pollution pose tremendous challenges to human development, and photocatalysis is considered to be an effective strategy to solve these problems. Herein, copper(II) tetra (4-carboxyphenyl) porphyrin (CuTCPP) molecules were successfully in situ loaded onto Bi4O5Br2 by a hydrothermal approach. A series of experimental results show that the light absorption capacity and photogenerated carrier separation efficiency were synchronously enhanced after the construction of CuTCPP/Bi4O5Br2 composites. Hence, the as-prepared composites possess significantly improved photocatalytic ability for both CO2 and Cr(VI) reduction. Specifically, CuTCPP/Bi4O5Br2-2 achieves a CO generation rate of 17.14 µmol g-1 under 5 h irradiation, which is twice as high as that of Bi4O5Br2 (8.57 µmol g-1). Besides, the optimized CuTCPP/Bi4O5Br2-2 also exhibits a removal rate of 61.87% for Cr(VI) within 100 min under irradiation. Furthermore, the mechanism of CO2 and Cr(VI) photoreduction was explored by in situ Fourier transform infrared spectroscopy and capture experiments, respectively. This work can be a reference toward the construction of photocatalysts with high activity for solar energy conversion.

2.
J Colloid Interface Sci ; 665: 825-837, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38564946

ABSTRACT

Photocatalytic peroxymonosulfate (PMS) oxidation systems demonstrate significant potential and promising prospects through the interconnection of photocatalytic and PMS oxidation for simultaneously achieving efficient pollutant removal and reduction of PMS dosage, which prevents resource wastage and secondary pollution. In this study, a Z-scheme Bi25FeO40/BiOCl (BOFC) heterojunction was constructed to carry out the photocatalytic PMS oxidation process for tetracyclines (TCs) pollutants at low PMS concentrations (0.08 mM). The photocatalytic PMS oxidation rate of Bi25FeO40/BiOCl composites for tetracycline hydrochloride (TCH), chlortetracycline (CTC), oxytetracycline (OTC) and doxycycline (DXC) reaches 86.6%, 83.6%, 86.7%, and 88.0% within 120 min. Simultaneously, the BOFC/PMS system under visible light (Vis) equally displayed the practical application prospects for the solo and mixed simulated TCs antibiotics wastewater. Based on the electron spin resonance (ESR) and X-ray photoelectron spectroscopy (XPS) valence band spectrum, a Z-scheme electron migration pathway was proposed to elucidate the mechanism underlying the performance enhancement of BOFC composites. Bi25FeO40 in BOFC composites can serve as active site for activating PMS by the formation of Fe3+/Fe2+ cycle. Toxicity estimation software tool (T.E.S.T.) and mung beans planting experiment demonstrates that BOFC/PMS/Vis system can reduce toxicity of TCs wastewater. Therefore, BOFC/PMS/Vis system achieves efficient examination in different water environments and efficient utilization of PMS, which displays a scientific reference for achieving environmentally-friendly and resource-saving handling processes.


Subject(s)
Environmental Pollutants , Peroxides , Wastewater , Reactive Oxygen Species , Anti-Bacterial Agents , Tetracycline , Light , Tetracyclines , Oxygen
3.
Talanta ; 246: 123515, 2022 Aug 15.
Article in English | MEDLINE | ID: mdl-35533566

ABSTRACT

Highly sensitive detection of enrofloxacin (ENR) is crucial for contaminant detection and environmental protection. A sensitive and selective photoelectrochemical (PEC) aptasensor was assembled by Au nanoparticles sensitized Bi24O31Br10 (Au/Bi24O31Br10) composites for detecting ENR. Due to the synergistic effect of bismuth-rich strategy and surface plasmon resonance (SPR) effect, Au/Bi24O31Br10 possessed promoted visible light absorption capacity further enhancing PEC performance and detection sensitivity of the constructed PEC aptasensor. By chemically adsorption effect between the sulfhydryl modified aptamer and Au nanoparticles, the ENR-aptamer was introduced into the PEC sensor to achieve highly selective detection of ENR. The PEC ENR aptasensor based on Au/Bi24O31Br10 composites possessed a broad linear detection scope (0.72-36000 ng L-1), satisfactory limit of detection (0.30 ng L-1, S/N = 3), high selectivity and stability. This work provides a new way for the trace detection of antibiotics in environmental analysis field.


Subject(s)
Aptamers, Nucleotide , Biosensing Techniques , Metal Nanoparticles , Bismuth , Electrochemical Techniques , Enrofloxacin , Gold , Limit of Detection
4.
Mikrochim Acta ; 188(9): 289, 2021 08 05.
Article in English | MEDLINE | ID: mdl-34355248

ABSTRACT

A photoelectrochemical (PEC) aptasensor was designed and constructed by Bi24O31Cl10/BiOCl heterojunction as a photoelectric active material for realizing the determination of trace ciprofloxacin (CIP) in water. Compared with Bi24O31Cl10, Bi24O31Cl10/BiOCl heterojunction possessed the improvement of light harvesting and the enhancement of photocurrent signal. The formation of heterojunction between Bi24O31Cl10 and BiOCl can accelerate the transportation efficiency and inhibit the recombination rate of photoinduced carriers. Based on the excellent PEC performance, CIP aptamer was introduced on the modified Bi24O31Cl10/BiOCl/indium tin oxide (ITO) electrode for fabricating a PEC aptasensor. Owing to the combination between aptamer and CIP, CIP-aptamer complex can block the transfer of charge, leading to the reduction of photocurrent response. The PEC aptasensor possessed high sensitivity with a wide detection range (5.0~1.0 × 104 ng L-1) and a low detection limit (1.67 ng L-1, S/N = 3). The PEC aptasensor with good selectivity and reproducibility has been applied to the determination of CIP in water.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Aptamers, Nucleotide/metabolism , Ciprofloxacin/therapeutic use , Electrochemical Techniques/methods , Anti-Bacterial Agents/pharmacology , Ciprofloxacin/pharmacology , Humans
5.
Analyst ; 145(23): 7695-7700, 2020 Nov 23.
Article in English | MEDLINE | ID: mdl-32985629

ABSTRACT

A photoelectrochemical (PEC) aptasensor based on silver nanoparticle/BiOCl (AgNP/BiOCl) composites was constructed for detecting chloramphenicol (CAP). The surface-plasmon resonance (SPR) effect of AgNPs can focus the incident light and promote the migration and separation of the photogenerated carriers of AgNP/BiOCl composites. As a result, the AgNP/BiOCl composites showed an enhanced PEC performance compared to that of pure BiOCl. A PEC CAP aptasensor was fabricated using AgNP/BiOCl composites as photoactive materials and a CAP aptamer as a recognition element. The PEC aptasensor exhibited a broad linear response range (0.2 pM-10 nM), a low limit of determination (0.08 pM), satisfactory selectivity, stability, and reproducibility to meet the practical analysis requirements. This work demonstrates that the PEC CAP aptasensor has a promising prospect in environmental assays.

6.
Anal Chim Acta ; 1125: 299-307, 2020 Aug 15.
Article in English | MEDLINE | ID: mdl-32674777

ABSTRACT

As a broad-spectrum tetracycline antibiotic, the overuse of oxytetracycline (OTC) causes antibiotics residues in the environment and seriously threats to human health owing to effective antibacterial properties. Thus, it is particularly important to design a photoelectrochemical (PEC) aptasensor to detect OTC with excellent performance. Herein, we developed a selective and stable PEC aptasensor of OTC on the basis of Co3O4 nanoparticles (Co3O4 NPs)/graphitic carbon nitride (g-CN) heterojunction, used as PEC active materials. The Co3O4 NPs were successfully grown on the g-CN via grinding and calcining mixture of Co3O4 precursors and bulk g-CN. The Co3O4/g-CN heterojunction with improved light utilization and promoted electrons/holes separation capability can exhibit higher PEC signal than that of g-CN. In order to implement the purpose of specific recognition, OTC-aptamer was introduced into modified electrode to construct highly selective PEC aptasensor for OTC determination, which can possess wide linear range (0.01-500 nM) with low detection limit (3.5 pM, S/N = 3). This PEC aptasensor platform with excellent selectivity and high stability can provide a practical application in the field of water monitoring.


Subject(s)
Aptamers, Nucleotide/chemistry , Biosensing Techniques/methods , Electrochemical Techniques/methods , Metal Nanoparticles/chemistry , Oxytetracycline/analysis , Photochemistry/methods , Base Sequence , Cobalt/chemistry , Cobalt/radiation effects , Graphite/chemistry , Graphite/radiation effects , Light , Limit of Detection , Metal Nanoparticles/radiation effects , Nitrogen Compounds/chemistry , Nitrogen Compounds/radiation effects , Oxides/chemistry , Oxides/radiation effects , Oxytetracycline/chemistry , Reproducibility of Results , Rivers/chemistry , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/chemistry
7.
Biosens Bioelectron ; 148: 111802, 2020 Jan 15.
Article in English | MEDLINE | ID: mdl-31665671

ABSTRACT

Ciprofloxacin (CIP) as a typical antibiotic is widely used to produce antimicrobial drugs. Determination of CIP has raised extensive concern due to its possible toxic effects on human health. Here, a simple photoelectrochemical (PEC) sensor for detecting CIP has been developed by using the nitrogen-deficient graphitic carbon nitride (ND-g-CN) as a PEC active material. The ND-g-CN material exhibits two-dimension (2D) thin sheet structure with abundant nitrogen vacancies. The 2D thin sheet structure can enable the effective charge separation and transfer, thus dramatically improving the PEC performance. Simultaneously, nitrogen vacancies can serve as charge trap to efficiently inhibit the charge recombination. Furthermore, the synergistic effect of the two can widen the absorption edge and decrease the band gap of ND-g-CN material, resulting in increasing light harvesting and enhancing PEC performance. CIP can be oxidized by the holes of ND-g-CN, thus realizing effective charge separation, which can result in the amplification of the photocurrent. The designed PEC sensor demonstrated a wide detection range from 60 to 19090 ng L-1 and a low detection limit of 20 ng L-1 for CIP assay. This strategy broadens the application of graphitic carbon nitride (g-CN) material in PEC field and presents a promising potential for the practical application in the environmental monitoring.


Subject(s)
Anti-Bacterial Agents/analysis , Ciprofloxacin/analysis , Electrochemical Techniques/methods , Graphite/chemistry , Nitrogen Compounds/chemistry , Nitrogen/chemistry , Animals , Electrons , Food Contamination/analysis , Light , Limit of Detection , Milk/chemistry , Sewage/analysis , Water Pollutants, Chemical/analysis
8.
Mikrochim Acta ; 186(11): 737, 2019 11 01.
Article in English | MEDLINE | ID: mdl-31673790

ABSTRACT

A self-powered photoelectrochemical (PEC) aptamer probe is presented for the determination of oxytetracycline (OTC). The assay is based on the use of g-C3N4 and NiO nanocrystals (NCs) which form a heterojunction. The latter was prepared by two-step hydrothermal pyrolysis by using the ionic liquid 1-hydroxyethyl-3-methylimidazole chloride which functions as a morphological template to form NiO NCs. The heterojunction exhibits much better electronic conductivity, wider absorption range, higher electron-hole-separation productivity, and stronger photocurrent compared to plain g-C3N4. The heterojunction was adopted to construct a self-powered PEC aptamer probe for OTC detection. An OTC-binding aptamer was immobilized on the heterojunction and the probe was constructed. The aptamer on the probe binding with OTC can form steric hindrance for transmitting of electrons and cause the PEC signal change depending on the OTC concentration. The photocurrent decreases with increasing OTC concentration in the 0.01 to 100 nM concentration range and its detection limit is 4 pM (at S/N = 3). Graphical abstract Schematic representation of a self-powered photochemical aptamer probe. The probe performs enhanced ability for oxytetracycline (OTC) determination due to the formation of NiO nanocrystals/g-C3N4 (NiO NCs/g-C3N4) heterojunction and the specification recognition of the aptamer.

9.
Mikrochim Acta ; 186(12): 794, 2019 11 16.
Article in English | MEDLINE | ID: mdl-31734780

ABSTRACT

A photoelectrochemical (PEC) aptasensor is described for detecting tetracycline (TC). A gold nanoparticles/BiOBr (AuNPs/BiOBr) composite was prepared where the AuNPs play a key function in carrier transfer which is ascribed to the wavelength-dependent dual function as an electron sink and as a hot-electron donor. Due to this dual function, the composite exhibits a wide photo-response and high electron transfer efficiency. This results in enormously enhanced PEC response. The TC-aptamer was immobilized on an ITO modified with AuNPs/BiOBr via Au-S covalent bonding. The resulting PEC aptasensor possesses a wide linear range (1-104 ng L-1) and a low detection limit (0.35 ng L-1; at S/N = 3). Graphical abstractSchematic representation of a photoelectrochemical aptasensor for tetracycline based on the use of a AuNP/BiOBr composite with electron sink and hot-electron donor properties of the gold nanoparticles.


Subject(s)
Aptamers, Nucleotide/chemistry , Biosensing Techniques/methods , Bismuth/chemistry , Electrochemical Techniques/methods , Metal Nanoparticles/chemistry , Tetracycline/analysis , Anti-Bacterial Agents/analysis , Anti-Bacterial Agents/chemistry , Gold/chemistry , Limit of Detection , Nanocomposites/chemistry , Nanocomposites/radiation effects , Reproducibility of Results , Tetracycline/chemistry , Ultraviolet Rays
10.
Dalton Trans ; 47(38): 13353-13359, 2018 Oct 02.
Article in English | MEDLINE | ID: mdl-30156238

ABSTRACT

It is generally known that pollution by 4-chlorophenol (4-CP) raises environmental concerns owing to the high toxicity of 4-CP. The necessity for determining and controlling the presence of 4-CP in the aqueous environment to achieve good water-quality objectives is now well recognized. Thus, a sensitive photoelectrochemical (PEC) sensing platform was fabricated on the basis of a BiPO4 nanocrystal/BiOBr (BiPO4/BiOBr) heterojunction for monitoring 4-CP. The BiPO4/BiOBr heterojunction was prepared using an in situ hydrothermal route assisted by the ionic liquids 1-hexadecyl-3-methylimidazolium bromide ([C16mim]Br) as the source of Br, and 1-octyl-3-methylimidazolium dihydrogen phosphate ([Omim]H2PO4) as the P source. Ionic liquids can also act as morphological templates, and have been considered to offer a suitable green route to nanocrystal synthesis. The resultant BiPO4/BiOBr heterojunction presented a higher PEC response than BiOBr. The BiPO4/BiOBr/ITO displayed an obvious photocurrent increment against 160 ng mL-1 4-CP, and therefore a PEC sensing platform on the basis of a BiPO4/BiOBr heterojunction was fabricated for monitoring 4-CP. This PEC sensor exhibited a wide linear range from 8.00 to 2400.00 ng mL-1 with a low detection limit, high selectivity, and good anti-interference properties. The as-prepared PEC sensor is expected to be utilized to determine 4-CP, and offers an important analytical method for rapid detection in real samples.

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