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1.
ChemSusChem ; 2023 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-36683007

RESUMO

The electrochemical nitrogen (N2) reduction reaction (N2RR) under mild conditions is a promising and environmentally friendly alternative to the traditional Haber-Bosch process with high energy consumption and greenhouse emission for the synthesis of ammonia (NH3), but a high-yield production is hindered by the strong nonpolar N≡N bond toward N2 moleculesdissociation or activation. Herein, disordered Au nanoclusters anchored on two-dimensional Ti3C2Tx MXene ultrathin nanosheets are rationally integrated and explored as highly active and selective electrocatalysts for efficient N2-to-NH3 conversion, achieving an exceptional activity with an NH3 yield rate of 88.3 ± 1.7 µg h-1 mgcat.-1 and a Faradaic efficiency of 9.3 ± 0.4 %. A combination of in-situ near-ambient pressure X-ray photoelectron spectroscopy and operando X-ray absorption fine structure is employed to unveil the uniqueness of the catalyst for N2RR, which demonstrated that the disordered structure could serve as active sites for N2 molecules chemisorption and activation during the N2RR process.

2.
Anal Chem ; 95(2): 570-574, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36596251

RESUMO

Cathodic electrochemiluminesence (ECL) microscopy based on luminol analog L012 was originally established to implement the imaging of a single nanotube and nucleolin on a single tumor cell. This microscopy utilizes multiwalled carbon nanotubes (MWCNTs) as advanced coreactant accelerators to efficiently convert dissolved oxygen (O2) and H2O2 into reactive oxygen species (ROS) due to excellent electrocatalytic properties. The produced ROS could oxide L012 into an excited state of L012 leading to a bright cathodic ECL illumination, thereby promoting ECL imaging of MWCNTs at a low triggering potential. After being modified with AS1411 aptamers, MWCNTs@AS1411 probes were incubated with tumor cells for specific ECL imaging of nucleolin on the plasma membrane, which permits cathodic ECL microscopy for label-free bioassays without ECL tags. The L012-based cathodic ECL microscopy with a moderate operating potential and label-free characteristics provides a universal approach in single nanomaterial and single-cell imaging and analyses.


Assuntos
Técnicas Biossensoriais , Nanotubos de Carbono , Análise de Célula Única , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Peróxido de Hidrogênio , Medições Luminescentes/métodos , Luminol , Microscopia , Espécies Reativas de Oxigênio , Análise de Célula Única/métodos
3.
Anal Chem ; 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36716431

RESUMO

Herein, a chemiluminescence (CL) biosensor based on CRISPR-Cas12a and cation exchange reaction was constructed to detect the biomarker microRNA-21 (miRNA-21). The rolling circle amplification (RCA) reaction was introduced to convert each target RNA strand into a long single-stranded DNA with repeated sequences, which acted as triggers to initiate the transcleavage activity of CRISPR-Cas12a. The activated Cas12a could cleave the biotinylated linker DNA of CuS nanoparticles (NPs) to inhibit the binding of CuS NPs to streptavidin immobilized on the surface of the microplate, which strongly reduced the generation of Cu2+ from a cation exchange between CuS NPs and AgNO3, and thus efficiently suppressed the CL of Cu2+-luminol-H2O2 system, giving a "signal off" biosensor. With the multiple amplification, the detection limit of the developed sensor for miRNA-21 reached 16 aM. In addition, this biosensor is not only suitable for a professional chemiluminescence instrument but also for a smartphone used as a detection tool for the purpose of portable and low-cost assay. This method could be used to specifically detect quite a low level of miRNA-21 in human serum samples and various cancer cells, indicating its potential in ultrasensitive molecular diagnostics.

4.
Small ; : e2207249, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36605005

RESUMO

Since the discovery of graphene, research on the family of 2D materials has been a thriving field. Metal phosphorous chalcogenides (MPX3 ) have attracted renewed attention due to their distinctive physical and chemical properties. The advantages of MPX3 , such as tunable layered structures, unique electronic properties, thermodynamically appropriate band alignments and abundant catalytic active sites on the surface, make MPX3 material great potential in electrocatalysis. In this review, the applications of MPX3 electrocatalysts in recent years, including hydrogen evolution reaction, oxygen evolution reaction, and oxygen reduction reaction, are summarized. Structural regulation, chemical doping and multi-material composite that are often effective and practical research methods to further optimize the catalytic properties of these materials, are introduced. Finally, the challenges and opportunities for electrocatalytic applications of MPX3 materials are discussed. This report aims to advance future efforts to develop MPX3 and related materials for electrocatalysis.

5.
Chemistry ; 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36628553

RESUMO

Exploiting effective non-noble metal electrocatalysts for oxygen reduction reaction (ORR) is crucial for fuel cells and metal-air batteries. Herein, we designed and fabricated Co nanoparticles confined in Mo/N co-doped polyhedral carbon frameworks (Co-NP/MNCF) derived from polyoxometalate-encapsuled metal-organic framework, which showed comparable ORR performance with commercial Pt/C and a larger diffusion-limited current density. Moreover, the Co-NP/MNCF also exhibited excellent ORR stability and methanol tolerance. These appealing performances can be attributed to the porosity regulation and heteroatom doping of MOF derived polyhedral carbon frameworks, which could be beneficial for the exposure of more active sites, the optimization of electronic structure and the mass transfer of electrolyte/electro/ion.

6.
Nanomaterials (Basel) ; 13(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36678060

RESUMO

Single-atom catalysts (SACs) have emerged as well-known catalysts in renewable energy storage and conversion systems. Several supports have been developed for stabilizing single-atom catalytic sites, e.g., organic-, metal-, and carbonaceous matrices. Noticeably, the metal species and their local atomic coordination environments have a strong influence on the electrocatalytic capabilities of metal atom active centers. In particular, asymmetric atom electrocatalysts exhibit unique properties and an unexpected carbon dioxide reduction reaction (CO2RR) performance different from those of traditional metal-N4 sites. This review summarizes the recent development of asymmetric atom sites for the CO2RR with emphasis on the coordination structure regulation strategies and their effects on CO2RR performance. Ultimately, several scientific possibilities are proffered with the aim of further expanding and deepening the advancement of asymmetric atom electrocatalysts for the CO2RR.

7.
Nanomaterials (Basel) ; 13(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36678085

RESUMO

Tobacco bacterial wilt is a serious disease caused by the soil-borne bacterium Ralstonia solanacearum (R. solanacearum). Herein, a rapid and purification-free α-hemolysin (α-HL) nanopore-sensing strategy based on polymerase chain reaction (PCR) and lambda exonuclease digestion was established to detect R. solanacearum. A 198-nucleotide-long single-stranded DNA was obtained via asymmetric PCR or the lambda exonuclease-mediated digestion of the PCR product. The DNA fragment produced unique long-lived, current-blocking signals when it passed through the α-HL nanopore. This sensing approach can allow for the determination of R. solanacearum in tobacco samples and can be conveniently extended to other DNA monitoring because of the extremely wide range of PCR applications.

8.
Food Chem ; 409: 135340, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-36592600

RESUMO

Small structural differences bring great difficulties on carbohydrates identification, especially in terms of their quantification. Herein, a novel ESI-MS/MS based strategy was established to discriminate and relatively quantified protonated PMP-disaccharides with different composition and glycosidic bond. Interestingly, protonated PMP labeled-disaccharides provided abundant fragment ions arising from cross-ring cleavage and glycosidic bond cleavage, which could afford diagnostic fragment patterns for isomers differentiation in combination of statistical analysis. It was worth to note that the relative intensity ratios (RIR) of three ion pairs could completely discriminate 16 disaccharides, and subsequently used to relatively quantified isomers in a binary mixture. Ultimately, this method was applied for the discrimination of yellow rice wine, and then the relative content of maltose and isomaltose were confirmed as well. In general, this method was easy to operation and effective for rapid differentiation and quantification of isomeric disaccharides in complex matrices.


Assuntos
Dissacarídeos , Vinho , Dissacarídeos/análise , Espectrometria de Massas em Tandem/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Isomerismo , Íons , Glicosídeos
9.
ACS Appl Mater Interfaces ; 15(4): 5954-5962, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36661841

RESUMO

Achieving the controlled release of functional substances is indispensable in many aspects of life. Especially for the aroma molecules, their effective delivery of flavor and fragrance is challenging. Here, selected pyridines, as highly volatile odorants, were individually coordinated with copper(I) iodide (CuII) via a straightforward one-pot synthesis method, rapidly forming pure or even crystalline CuII cluster-based profragrances at room temperature. The obtained profragrances enabled the stable and high loading of volatile fragrances under ambient conditions and guaranteed their long-lasting release during heating. Furthermore, the intrinsic emission luminescence of these solid-state profragrances decayed along with the aroma release, which can serve as an additional indicator for monitoring the delivery process. This research sets a precedent for using CuII clusters as dual-purpose release agents and greatly expands their potential applications.

10.
J Hazard Mater ; 447: 130781, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36641851

RESUMO

PCBs bioremediation is largely impeded by the reduced metabolic activity and degradation ability of indigenous and exogenous microorganisms. Resuscitation promoting factor (Rpf) of Micrococcus luteus, has been reported to resuscitate and stimulate the growth of PCB-degrading bacterial populations, and the resuscitated strains exhibited excellent PCB-degrading performances. Therefore, this study was conducted to assess the feasibility of supplementing Rpf (SR) or resuscitated strain LS1 (SL), or both (SRL) for enhanced bioremediation of PCB-contaminated soil. The results indicated that Rpf and/or LS1 amended soil microcosms achieved more rapid PCBs degradation, which were 1.1-3.2 times faster than control microcosms. Although soil-inoculated LS1 maintained the PCB-degrading activity, higher PCBs degradation was observed in Rpf-amended soil microcosms compared with SL. The order of enhancement effect on PCBs bioremediation was SRL > SR > SL. PCBs degradation in soil microcosms was via HOPDA-benzoate-catechol/protocatechuate pathways. The improved PCBs degradation in Rpf-amended soil microcosms was attributed to the enhanced abundances of PCB-degrading populations which were mainly belonged to Proteobacteria and Actinobacteria. These results suggest that Rpf and resuscitated strains serve as effective additive and bio-inoculant for enhanced bioremediation, providing new approaches to realizing large scale applications of in situ bioremediation.

11.
Chem Commun (Camb) ; 59(4): 442-445, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36519313

RESUMO

Here, we report that a Bi-doped Co3O4 nanosheet array grown on Ni foam can selectively catalyze HMF-to-FDCA oxidation at ambient conditions. The catalyst shows a faradaic efficiency of 97.7%, a yield rate of 362.5 µmol h-1, and a conversion of nearly 100%, surpassing those of pristine Co3O4. Furthermore, when the catalyst was adopted as both the anode and cathode in a two-electrode system, H2 and FDCA can be produced simultaneously.

12.
J Chromatogr A ; 1689: 463745, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36586287

RESUMO

In this work, Friedel-Crafts alkylation was successfully applied to prepare a magnetic ionic liquid hypercrosslinked polymer composite (Fe3O4@IL-HCP), which was subsequently employed as magnetic solid-phase extraction (MSPE) adsorbent for the isolation and enrichment of trace non-steroidal anti-inflammatory drugs (NSAIDs). The developed composite was comprehensively characterized using various techniques, with the results indicating that it possessed high saturation magnetization (39.44 em g - 1), large specific surface area (175 m2g - 1), and high adsorption capacity for NSAIDs. The adsorption behavior and mechanisms were also investigated in detail. NSAIDs were adsorbed onto the Fe3O4@IL-HCP sorbent via a heterogeneous multilayer process consisting of hydrogen bonding and π-π and electrostatic interactions. Additionally, the composite's large surface area and multiple active sites enabled extraction equilibrium within 6 min. By coupling with high performance liquid chromatography (HPLC), the developed MSPE/HPLC method was applied for the determination of selected NSAIDs in water and urine samples. The developed method displayed wide linear ranges, low limits of detection (0.12-0.30 ng mL-1 and 0.15-1.5 ng mL-1 in water and urine samples, respectively), sufficient recoveries (92.8-109%), and good precision (relative standard deviations ≤ 4.6%). Thus, the findings of this work provide an appealing alternative for the extraction and determination of trace NSAIDs in environmental water and biological samples.


Assuntos
Líquidos Iônicos , Água , Água/química , Líquidos Iônicos/análise , Polímeros/química , Anti-Inflamatórios não Esteroides/análise , Extração em Fase Sólida/métodos , Adsorção , Fenômenos Magnéticos , Cromatografia Líquida de Alta Pressão , Limite de Detecção
13.
Biosens Bioelectron ; 222: 114997, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36516629

RESUMO

MicroRNAs (miRNAs) are very important for the early diagnosis and prognosis of tumors. In this work, we achieved the simultaneous detection of microRNA-155 (miR-155) and microRNA-21 (miR-21) with a dual target recognition probe (DRP) based on the nonlinear hybridization chain reaction (HCR). The multi-branched DNA products, three-dimensional multi-hotspot DNA dendrimers (3DmhD) were used in the amplification of the target miRNAs signal. The DRP is constructed with a core of gold nanocages (AuNCs), modified by nucleic acid probes and labeled with Raman signaling molecules ROX and Cy3. Experiments demonstrated that DRP could activate the multi-branched DNA reaction and generate 3DmhD in the presence of miR-155 and miR-21, which can achieve effective amplification of miR-21 and miR-155. When Surface Enhanced Raman Scattering (SERS) analysis was performed on 3DmhD, the multi-hot spot effect of 3DmhD significantly enhanced the signals of ROX and Cy3, allowing ultra-sensitive detection of miR-21 and miR-155 in vitro. To our delight, DRP also exhibited sensitive specificity and significant signal amplification for intracellular miRNAs. These results revealed that DRP has the potential to screen tumor cells by analyzing the expression levels of intracellular miRNAs.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , MicroRNAs , MicroRNAs/genética , MicroRNAs/análise , Técnicas Biossensoriais/métodos , DNA , Análise Espectral Raman/métodos , Ouro , Catálise
14.
Acta Biomater ; 157: 538-550, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36494007

RESUMO

Most photosensitizer molecules used for the photodynamic therapy (PDT) are chemically-synthesized organic photosensitizer dyes which show several limitations such as unsatisfactory cell uptake, weak selectivity and off-target phototoxicity. Recently, genetically-encoded photosensitizers have attracted increasing attentions which provide the targeted cell elimination with single-cell precision. However, their applications are mainly limited by the shallow tissue penetration depth of the excitation light and the low cell apoptosis ratio. Herein, we developed a feasible upconversion nanoparticle (UCNP)-based optogenetic nanosystem with three-in-one functional integration: bio-imaging, NIR-triggered PDT and cascade gene therapy. Firstly, the mitochondria-targeted genetically-encoded photosensitizer was constructed and transfected into cancer cells. Then, the functional upconversion nanoprobe was constructed with the mitochondria targetability and then the siRNA was loaded on the surface of UCNPs via the reactive oxygen species (ROSs) sensitive chemical bond. After the transfection and incubation, both of the upconversion nanoprobe and the genetically-encoded photosensitizer were accumulated in the mitochondria of cancer cells. Under the NIR irradiation, the emission of UCNPs could excite the expressed protein photosensitizer to generate ROSs which then stimulated the release of siRNAs in a controllable manner, achieving PDT and cascade gene therapy. Since the generation of ROSs and the release of siRNA occurred in the mitochondria in-situ, the mitochondria-mediated cell apoptosis signal pathway would be activated to induce cell apoptosis and subsequently inhibit tumor growth. To the best of our knowledge, this is the first report about NIR laser-activated, organelle-localized genetically-encoded photosensitizers developed for cascade therapy, which will widen the application of optogenetic tools in the tumor therapy. STATEMENT OF SIGNIFICANCE: The application of genetically-encoded photosensitizers in photodynamic therapy (PDT) is mainly limited by the shallow tissue penetration depth of the excitation light and unsatisfactory therapeutic performance. In this experiment, we developed an upconversion nanoparticles-based optogenetic nanosystem to enhance the PDT and cascade gene therapy for malignant tumors. The expressed genetically-encoded photosensitizers were accumulated in the mitochondria, which were activated in situ by the upconversion nanoprobe. Besides, the photogenerated reactive oxygen species (ROSs) stimulated the release of siRNAs in a controllable manner. To the best of our knowledge, this is the first report about NIR laser-activated, genetically-encoded photosensitizers developed for organelle-localized controllable cascade therapy. We hope this work can accelerate the application of genetically-encoded photosensitizers in the tumor therapy.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Fármacos Fotossensibilizantes/química , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio/metabolismo , Optogenética , Nanopartículas/química , Neoplasias/tratamento farmacológico , Terapia Genética , RNA Interferente Pequeno/uso terapêutico , Linhagem Celular Tumoral
15.
J Colloid Interface Sci ; 634: 730-736, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36563429

RESUMO

Electrocatalytic water splitting is a promising technology for sustainable hydrogen (H2) production; however, it is restricted by the kinetically sluggish anodic oxygen evolution reaction (OER). Replacing OER with urea oxidation reaction (UOR) with low thermodynamic potential can simultaneously improve the energy efficiency of H2 production and purify urea-containing wastewater. Here we report a facile assembly-calcination two-step method to synthesize heterogeneous Ni-MoN nanosheet-assembled microspheres (Ni-MoN NAMs). The nanosheet-assembled structure and the synergistic metallic Ni-MoN heterogeneous interface endow the Ni-MoN NAMs with good OER (1.52 V@10 mA cm-2), UOR (1.28 V@10 mA cm-2), and hydrogen evolution reaction (HER, 0.16 V@10 mA cm-2) activity. The two-electrode urea electrolysis cell with Ni-MoN NAMs as both the cathode and anode requires an extremely low cell voltage of 1.41 V to afford 20 mA cm-2, which is 0.3 V lower than that of the water electrolyzer, paving the way for energy-saving H2 production.


Assuntos
Hidrogênio , Oxigênio , Microesferas , Ureia , Água
16.
Anal Chem ; 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36473140

RESUMO

The amine submetabolome, including amino acids (AAs) and biogenic amines (BAs), is a class of small molecular compounds exhibiting important physiological activities. Here, a new pyrylium salt named 6,7-dimethoxy-3-methyl isochromenylium tetrafluoroborate ([d0]-DMMIC) with stable isotope-labeled reagents ([d3]-/[d6]-DMMIC) was designed and synthesized for amino compounds. [d0]-/[d3]-/[d6]-DMMIC-derivatized had a charged tag and formed a set of molecular ions with an increase of 3.02 m/z and the characteristic fragment ions of m/z 204.1:207.1:210.1. When DMMIC coupled with liquid chromatography-mass spectrometry (LC-MS), a systematic methodology evaluation for quantitation proved to have good linearity (R2 between 0.9904 and 0.9998), precision (interday: 2.2-21.9%; intraday: 1.0-19.7%), and accuracy (recovery: 71.8-108.8%) through the test AAs. Finally, the methods based on DMMIC and LC-MS demonstrated the advantaged application by the nontargeted screening of BAs in a common medicinal herb Senecio scandens and an analysis of metabolic differences among the amine submetabolomes between the carcinoma and paracarcinoma tissues of esophageal squamous cell carcinoma (ESCC). A total of 20 BA candidates were discovered in S. scandens as well as the finding of 13 amine metabolites might be the highest-potential differential metabolites in ESCC. The results showed the ability of DMMIC coupled with LC-MS to analyze the amine submetabolome in herbs and clinical tissues.

17.
ACS Sens ; 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36455009

RESUMO

Acoustic-based imaging techniques, including ultrasonography and photoacoustic imaging, are powerful noninvasive approaches for tumor imaging owing to sound transmission facilitation, deep tissue penetration, and high spatiotemporal resolution. Usually, imaging modes were classified into "always-on" mode and "activatable" mode. Conventional "always-on" acoustic-based probes often have difficulty distinguishing lesion regions of interest from surrounding healthy tissues due to poor target-to-background signal ratios. As compared, activatable probes have attracted attention with improved sensitivity, which can boost or amplify imaging signals only in response to specific biomolecular recognition or interactions. The tumor microenvironment (TME) exhibits abnormal physiological conditions that can be used to identify tumor sections from normal tissues. Various types of organic dyes and biomaterials can react with TME, leading to obvious changes in their optical properties. The TME also affects the self-assembly or aggregation state of nanoparticles, which can be used to design activatable imaging probes. Moreover, acoustic-based imaging probes and therapeutic agents can be coencapsulated into one nanocarrier to develop nanotheranostic probes, achieving tumor imaging and cooperative therapy. Satisfactorily, ultrasound waves not only accelerate the release of encapsulated therapeutic agents but also activate therapeutic agents to exert or enhance their therapeutic performance. Meanwhile, various photoacoustic probes can convert photon energy into heat under irradiation, achieving photoacoustic imaging and cooperative photothermal therapy. In this review, we focus on the recently developed TME-triggered ultrasound and photoacoustic theranostic probes for precise tumor imaging and targeted tumor therapy.

18.
Front Bioeng Biotechnol ; 10: 1072205, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36507268

RESUMO

Lidocaine, a potent local anesthetic, is clinically used in nerve block and pain management. However, due to its short half-life, repeated administration is required. For this reason, here we designed and prepared a lidocaine-encapsulated polylactic acid-glycolic acid (Lidocaine@PLGA) microcapsule with ultrasound responsiveness to relieve the sciatica nerve pain. With a premixed membrane emulsification strategy, the fabricated lidocaine-embedded microcapsules possessed uniform particle size, good stability, injectability, and long-term sustained release both in vitro and in vivo. More importantly, Lidocaine@PLGA microcapsules had the function of ultrasonic responsive release, which made the drug release controllable with the effect of on-off administration. Our research showed that using ultrasound as a trigger switch could promote the rapid release of lidocaine from the microcapsules, achieving the dual effects of long-term sustained release and short-term ultrasound-triggered rapid release, which can enable the application of ultrasound-responsive Lidocaine@PLGA microcapsules to nerve root block and postoperative pain relief.

19.
Se Pu ; 40(11): 998-1004, 2022 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-36351808

RESUMO

A method based on solid-phase extraction-ultra performance liquid chromatography-tandem mass spectrometry (SPE-UPLC-MS/MS) was established for the determination of gpenicillin, cloxacillin, ampicillin residues in milk. Using self-made covalent triazine frameworks (CTFs) as the solid-phase extraction sorbents, the main factors influencing the efficiency of the solid-phase extraction columns, such as the sorbent amount, eluent type, eluent volume, and flow rate, were optimized. The extraction and purification conditions for the samples were also investigated. The optimal extraction effect was achieved at a flow rate of 3 mL/min with 60 mg CTFs and 6 mL eluent solution (acetonitrile). Separation was carried out on a Waters ACQUITY UPLC BEH C18 column, and 0.1% formic acid aqueous solution-acetonitrile was used as the mobile phases for gradient elution. The filtrate was detected by ultra performance liquid chromatography-tandem mass spectrometry, identified by electrospray ionization (ESI) in the positive mode using multiple reaction monitoring, and quantified using external standards. The calibration curves of the three penicillins showed good linearity and the correlation coefficients of the linear regression equations for the three target analytes were all greater than 0.999. The limits of detection (LODs) and limits of quantification (LOQs) were 0.05-0.10 µg/kg and 0.1-0.4 µg/kg, respectively. The average recoveries of the three analytes were 84.9%-94.1%, and the relative standard deviations (RSDs, n=5) were 1.66%-3.27%. Moreover, the mechanism of interaction between the CTFs and the target analytes was analyzed. The results revealed the existence of π-π and hydrogen-bond interactions between the CTFs and analytes. The results further indicated that the CTFs could be successfully used for the enrichment and purification of penicillins in milk. The proposed method has the advantages of high precision, good reproducibility, high resolution, and short analysis time, and it is suitable for the qualitative and quantitative determination of trace targets in complex matrices.


Assuntos
Leite , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida , Leite/química , Cromatografia Líquida de Alta Pressão , Triazinas/análise , Penicilinas/análise , Reprodutibilidade dos Testes , Extração em Fase Sólida , Acetonitrilas/análise
20.
Foods ; 11(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36429147

RESUMO

Xiao Mo Xiang You (XMXY) is a traditional Chinese sesame oil variety that is obtained through a hot water flotation process. This unique process gives the oil a unique aroma, health benefits, and excellent product stability. Although XMXY is always the most expensive among all the sesame oil varieties, it is usually used as a flavoring in many traditional Chinese daily food products and is increasingly popular. In order to reveal the characteristics of the oil, the volatile components, sensory evaluation, and oxidation stability of five XMXY samples were, respectively, analyzed by using headspace solid-phase microextraction/gas chromatography-mass spectrometry, an electronic nose, sensory evaluation, and RapidOxy. Comparisons and multidimensional statistical analysis were also carried out to distinguish XMXY from roasted sesame oil (RSO) and cold-pressed sesame oil (CSO) samples. In total, 69 volatiles were identified from XMXY, RSO, and CSO samples. Some compounds possessed high odor activity value (OAV > 1) in XMXY, including heterocyclic compounds, phenols, and sulfur-containing compounds. Additionally, they were also the main volatile components that distinguish XMXY from RSO and CSO. Roasted and nutty aromas were the dominant aroma attributes of XMXY. XMXY had better flavor intensity and oxidation stability than the other two sesame oil samples. These results are very valuable for the quality control and product identification of traditional Chinese sesame oil.

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