Analytical Methods最新文献

{"title":"Multivariate HPLC system assessment and optimization for traditional Chinese medicine: a case study of Gastrodia elata","authors":"Qilin Xu, Xinyi Huo, Xianggang Yin, XiaoHan Zhao, Meixu Chen, Linlin Wu, Yifeng Zhou","doi":"10.1039/d4ay01451k","DOIUrl":"https://doi.org/10.1039/d4ay01451k","url":null,"abstract":"The development of HPLC analytical methods for traditional Chinese medicine is intricate and time-consuming, influenced by factors such as column wear, solvent purity, and instrumental settings. A comprehensive evaluation of the HPLC system is crucial to mitigate potential variability and ensure the reliability of data. This is especially important given the complex and synergistic nature of the chemical components in traditional Chinese medicine, necessitating a multivariate measurement system analysis (MSA) to assess multiple correlated quality characteristics effectively. This study introduced a multivariate MSA method based on weighted principal components (WPC) to evaluate the HPLC system for the determination of metabolites in <em>Gastrodia elata</em>. By integrating multiple principal components and assigning weights according to their eigenvalues, the WPC method significantly enhanced both accuracy and robustness. It demonstrated a repeatability and reproducibility (% R&amp;R) of 26.43% and a number of distinct categories (ndc) index of 5, confirming the system's acceptability. A full factorial experimental design was employed to identify key performance factors, leading to the recommendation to use five reference solutions for the standard curve and to triple sample preparations for improved precision and accuracy. Monte Carlo simulations confirmed the reliability of the system, showing % R&amp;R and ndc values that follow a normal distribution, ranging from 19% to 22% and 6.07 to 7.38, respectively. Chromatographic conditions were optimized using a Box–Behnken experimental design. Subsequent validation experiments verified the method's high accuracy and reliability, with all relative standard deviation values for analytical precision, repeatability, and stability below 5%. The method also exhibited high recovery rates, exceeding 91% across three concentration levels, with RSD values under 4%. In conclusion, the application of a WPC-based multivariate MSA enabled a detailed evaluation of the HPLC system, ensuring accurate and reliable measurement of quality attributes. This method exemplified a scientifically rigorous approach for developing analytical methods in traditional Chinese medicine, enhancing both precision and reliability.","PeriodicalId":64,"journal":{"name":"Analytical Methods","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of gold nanoparticle-based lateral-flow strips for NGAL protein detection in urine samples","authors":"Paweena Tunakhun, Sawinee Ngernpimai, Patcharaporn Tippayawat, Kiattawee Choowongkomon, Sirirat Anutrakulchai, Nicha Charoensri, Ratree Tavichakorntrakool, Sakda Daduang, Oranee Srichaiyapol, Pornsuda Maraming, Patcharee Boonsiri, Jureerut Daduang","doi":"10.1039/d4ay00838c","DOIUrl":"https://doi.org/10.1039/d4ay00838c","url":null,"abstract":"This study focuses on enhancing the sensitivity of lateral-flow strips (LFSs) based on gold nanoparticles (AuNPs) for the detection of Neutrophil Gelatinase-Associated Lipocalin (NGAL) protein in urine samples. Several sizes of AuNP-based LFS biosensors were tested to optimize colorimetric signals for NGAL detection based on improved conjugation conditions. AuNPs of 39.8 nm diameter at pH 8 were the most sensitive for the detection of NGAL. Through systematic enhancements to the AuNP-based LFS, the study significantly improves the sensitivity, enabling the reliable detection of NGAL protein in urine samples at a level as low as 12.5 ng mL<small>⁻¹</small>. These advances contribute to the refinement of diagnostic tools for the early detection of kidney injury, specifically in cases associated with the presence of NGAL protein, offering a more precise and effective screening approach.","PeriodicalId":64,"journal":{"name":"Analytical Methods","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A cheap and straightforward method for the selective isolation of histidine-derived natural products using nickel(II) phosphate","authors":"Muhammad Saalim, Ya Lu, Kenneth J. Woycechowsky, Benjamin R. Clark","doi":"10.1039/d4ay01467g","DOIUrl":"https://doi.org/10.1039/d4ay01467g","url":null,"abstract":"Nickel-based resins have long been used in biochemical studies for the purification of His-tagged proteins, but their potential in the isolation of histidine-derived small molecules has not been investigated to date. Many agriculturally-important mycotoxins incorporate histidine residues, as do natural products from both plants and bacteria. Here, a highly-selective solid-phase extraction method is described for the purification of histidine-derived natural products using the insoluble nickel salt Ni<small>₃</small>(PO<small>₄</small>)<small>₂</small>. This led to the highly-selective binding and elution of two natural products, meleagrin and gartryprostatin C, from two fungal strains, <em>Penicillium chrysogenum</em> and <em>Aspergillus sclerotiorum</em>, respectively. A simple protocol involving binding, washing with water and methanol, and elution with methanolic acetate buffer, gave 65–75% recovery of both compounds directly from crude extracts of the two fungi. The procedure can easily be used as part of a multi-step isolation process in combination with HPLC to yield the purified alkaloids.","PeriodicalId":64,"journal":{"name":"Analytical Methods","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rapid assembly of mixed thiols for toll-like receptor-based electrochemical pathogen sensing","authors":"Rajesh G. Pillai, Khalid Azyat, Nora W. C. Chan, Abebaw B. Jemere","doi":"10.1039/d4ay00983e","DOIUrl":"https://doi.org/10.1039/d4ay00983e","url":null,"abstract":"Herein, we describe a rapid and facile fabrication of electrochemical sensors utilizing two different toll-like receptor (TLR) proteins as biorecognition elements to detect bacterial pathogen associated molecular patterns (PAMPs). Using potential-assisted self-assembly, binary mixtures of 11-mercaptoundecanoic acid (MUA) and 6-mercapto-1-hexanol (MCH), or MUA and an in-house synthesized zwitterionic sulfobetaine thiol (DPS) were assembled on a gold working electrode within 5 minutes, which is &gt;200 times shorter than other TLR sensors' preparation time. Electrochemical methods and X-ray photoelectron microscopy were used to characterize the SAM layers. SAMs composed of the betaine terminated thiol exhibited superior resistance to nonspecific interactions, and were used to develop the TLR sensors. Biosensors containing two individually immobilized TLRs (TLR4 and TLR9) were fabricated on separate MUA-DPS SAM modified Au electrodes (MUA-DPS/Au) and tested for their response towards their respective PAMPs. The changes to electron transfer resistance in EIS of the TLR4/MUA-DPS/Au sensor showed a detection limit of 4 ng mL<small>⁻¹</small> for <em>E. coli</em> 0157:H7 endotoxin (lipopolysaccharide, LPS) and a dynamic range of up to 1000 ng mL<small>⁻¹</small>. The TLR4-based sensor showed negligible response when tested with LPS spiked human plasma samples, showing no interference from the plasma matrix. The TLR9/MUA-DPS/Au sensor responded linearly up to 350 μg mL<small>⁻¹</small> bacterial DNA, with a detection limit of 7 μg mL<small>⁻¹</small>. The rapid assembly of the TLR sensors, excellent antifouling properties of the mixed SAM assembly, small size and ease of operation of EIS hold great promise for the development of a portable and automated broad-spectrum pathogen detection and classification tool.","PeriodicalId":64,"journal":{"name":"Analytical Methods","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A silicon-based functional self-assembled aptasensor for the detection of aflatoxin B1 by SERS sensing","authors":"Zhiming Guo, Xuan Fu, Ruiyun Zhou, Yang Zhang, Hesham El-Seedi, Nicholas Watson, Xiaobo Zou, Megan Povey","doi":"10.1039/d4ay01266f","DOIUrl":"https://doi.org/10.1039/d4ay01266f","url":null,"abstract":"One of the most harmful contaminants found in corn and its products is aflatoxin B1 (AFB1) and thus developing reliable detection methods is of great significance to consumers and the food industry. In this research, Au<small>^MBA</small>@Ag nanoparticles (NPs) and AgNPs deposited on a silicon wafer (Si@AgNPs) were functionalized with an aptamer and its complementary strand, respectively, and self-assembled into a SERS aptasensor, which generated strong SERS signals. AFB1 bound to the aptamer prior to the complementary chain, causing Au<small>^MBA</small>@Ag NPs to detach from Si@AgNPs. The complex dissociated, leading to a decrease in signal intensity from the solid-phase substrate. Under optimal conditions, the linear detection range was 0.05–20.0 ng mL<small>⁻¹</small>, and the detection limit was 0.039 ng mL<small>⁻¹</small>. Notably, the aptasensor demonstrated a recovery rate between 92.77% and 110.13% when utilized for the detection of AFB1 in corn flour and oil, indicating its good potential for detecting AFB1 in real sample matrices. In conclusion, a quantitative and reliable specific SERS detection system for AFB1 was developed in this study with significant applicability to food safety.","PeriodicalId":64,"journal":{"name":"Analytical Methods","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preparation and evaluation of Fe₃O₄@C@NiCo-LDH@CDs composites for magnetic solid-phase extraction of trace endocrine disruptors.","authors":"Honglin Qin, Ruozhu Xu, Lizhen Qiao, Xupeng Zhai, Peixin Guo, Chen Li, Bingyan Han","doi":"10.1039/d4ay00864b","DOIUrl":"https://doi.org/10.1039/d4ay00864b","url":null,"abstract":"<p><p>The widespread use of endocrine disruptors (EDPs) has certain potential hazards to organisms and environments, and it is particularly important to develop effective pretreatment methods before detection of EDPs in complex samples. In this work, a novel magnetic nanocomposite decorated with layered double hydroxides (LDHs) and carbon dots (CDs) was designed and prepared for magnetic solid-phase extraction (MSPE) of EDPs (bisphenol S, bisphenol F, bisphenol A, bisphenol AF, diethylstilbestrol and 4-cumylphenol) combined with high-performance liquid chromatography-ultraviolet (HPLC-UV) detection. The prepared composites were characterized by field emission scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS), and the adsorption mechanism towards these EDPs might be mainly based on hydrogen bonds and π-π conjugation. Under the optimized conditions, the proposed method showed limits of detection within 0.05-0.50 μg L^-1 and limits of quantitation within 0.2-2.0 μg L^-1, and good linearity (<i>R</i>² ≥ 0.9975) was presented in the range of 0.2-200 μg L^-1. Finally, the Fe₃O₄@C@NiCo-LDH@CDs composite-based MSPE-HPLC-UV method was applied for enrichment and determination of EDPs in water, milk, and tea beverage samples with recoveries in the range of 81.2-119.8% and relative standard deviations below 9.7%.</p>","PeriodicalId":64,"journal":{"name":"Analytical Methods","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142277389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coaxial burner system for solid-sample flame emission spectroscopy","authors":"Adam Bernicky, Boyd Davis, Hans-Peter Loock","doi":"10.1039/d4ay01183j","DOIUrl":"https://doi.org/10.1039/d4ay01183j","url":null,"abstract":"We present a burner system to analyze solid, inflammable samples by flame emission spectroscopy without requiring any sample preparation procedures. An acetylene–nitrous oxide burner was designed to efficiently introduce solid particles into the flame through active injection, enabling real-time elemental analysis. Computational fluid dynamics (CFD) simulations were employed to study particle transport dynamics within the burner system. The emission was characterized through spectral analysis of the flame emission from copper- and iron-metal powder mixtures, demonstrating its ability to determine elemental compositions without prior sample treatment. An artificial neural network (ANN) was implemented to analyze spectral data obtained from binary Cu/Fe metal mixtures, enabling rapid and reliable identification of constituent elements with an uncertainty of <em>σ</em> = 2.7 mol%. The blackbody temperature could be determined in the range of 2200–2600 K with an accuracy of 7 K.","PeriodicalId":64,"journal":{"name":"Analytical Methods","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electrochemical determination of captopril using disposable graphite electrode modified with a molecularly imprinted film, accompanied by a ratiometric read-out","authors":"Mohamed Mohamoud El-Wekil, Khalid Alhazzani, Al-Montaser Bellah H. Ali, Alanazi AZ, Hossieny Ibrahim, Mahmoud Darweesh","doi":"10.1039/d4ay00724g","DOIUrl":"https://doi.org/10.1039/d4ay00724g","url":null,"abstract":"In this research paper, a novel \"signal on-off\" ratiometric-based electrochemical platform was developed for the sensitive and selective detection of captopril. Ratiometric responses were achieved by fabricating molecularly-imprinted polymers (MIPs) on the surface of a graphite electrode (GE) decorated with nitrogen (N) and sulfur (S) co-doped porous carbon and silver nanoparticles (Ag). The MIP layer was formed via electropolymerization of copper coordinated with pyrrole-3-carboxylic acid (functional monomer). Silver nanoparticles (Ag) were incorporated to enhance conductivity, surface area, and to serve as an internal reference output. Upon the addition of captopril, there was a decrease in the anodic oxidation current of Ag+ at around 0.067 V, coupled with an increase in the oxidation current at 0.54 V (Ag-captopril complex). Under optimized conditions, the electrochemical responses (IAg-captopril/IAg) increased linearly with increasing captopril concentration in the range of 1-450 nM, with a detection limit (S/N=3) of 0.3 nM. The ratiometric-based MIP electrochemical platform (Cu-MIP/NS-PC@Ag/GE) was successfully applied to detect captopril in complex matrices such as tablets, serum, and urine samples. This platform holds promise for sensitive and selective detection of captopril in various practical applications.","PeriodicalId":64,"journal":{"name":"Analytical Methods","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142194750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A machine learning-driven SERS platform for precise detection and analysis of vascular calcification","authors":"Wei Li, Zhilian You, Dawei Cao, Naifeng Liu","doi":"10.1039/d4ay01061b","DOIUrl":"https://doi.org/10.1039/d4ay01061b","url":null,"abstract":"Vascular calcification (VC) significantly increases the incidence and mortality rates of cardiovascular diseases, severely threatening public health as a global issue. Currently, there are no effective methods to prevent and treat vascular calcification. This study proposes a machine learning-assisted surface-enhanced Raman scattering (SERS) technique for label-free, highly sensitive analysis of VC rat serum. We prepared gold nanobipyramid (GNBP) substrates using seed-mediated and liquid–liquid interface self-assembly methods and measured the SERS spectra of the serum. The collected spectral data were processed using a Principal Component Analysis (PCA)-Linear Discriminant Analysis (LDA) model to achieve effective sample differentiation. In this analysis model, GNBP substrates enabled rapid, sensitive, and label-free serum spectral detection, achieving classification accuracy, sensitivity, and specificity of 96.0%, and an AUC value of 0.98, significantly outperforming currently used machine learning methods. By analyzing the PCA loading plots, key spectral features that distinguished VC were successfully captured. This study demonstrates that combining SERS technology with machine learning provides a new method and foundation for real-time diagnosis and identification of VC, showcasing the significant advantages of GNBP substrates in high-sensitivity and high-specificity detection, potentially improving the early diagnosis and treatment of VC significantly.","PeriodicalId":64,"journal":{"name":"Analytical Methods","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142194754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a novel and useful methodology for the simultaneous analysis of multiclass contaminants in bovine fat","authors":"Rodrigo Souza, Natalia Gérez García, Natalia Besil, Maria Veronica Cesio, Horacio Heinzen, Maria Lucia Pareja","doi":"10.1039/d4ay00516c","DOIUrl":"https://doi.org/10.1039/d4ay00516c","url":null,"abstract":"The instrumental development of tandem mass spectrometers fosters the actual trend in the trace analysis of organic compounds to the development of methods that allow the analysis of contaminants of the most diverse origin in a single analytical sample. The multiclass methods are aligned with the Who´s One Health initiative while accomplishing the concepts of green chemistry. However, there are few reports of wide scope multiclass methods for the analysis of contaminants in this matrix. In this work, a method for the simultaneous determination of 62 compounds in bovine fat, was developed and validated following DG-SANTE/11813/2021 guidance. Liquid nitrogen milled fat was extracted with toluene and acetonitrile. Then a clean-up in a cryogenic bath, followed by dispersive solid phase extraction was performed. Residue determination was done using liquid chromatography for 44 compounds and gas chromatography for 18 compounds, both coupled to tandem mass spectrometry in MRM mode. The method was first developed and validated for two ectoparasiticides, then the scope was expanded for the analysis of 13 veterinary drugs and 49 pesticides. Recovery percentages were in the range of 60-134%, high matrix effect was observed in 50% of the scope of the method. Most compounds presented limits of quantification of 10 µg kg-1 in compliance with international requirements. The method was applied to monitor 49 commercial samples to evaluate its performance. Eighty percent of samples contained ethion and 10% had fluazuron, both within MRLs, highlighting the need for proper withdrawal times.","PeriodicalId":64,"journal":{"name":"Analytical Methods","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142194753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}