Analytical Chemistry最新文献

Sugar Analysis Using Hydrophilic Liquid Chromatography Combined with Raman Spectroscopy 亲水液相色谱结合拉曼光谱分析糖

IF 7.4 1区化学 Q1 CHEMISTRY, ANALYTICAL

Analytical Chemistry

Pub Date : 2025-06-14 DOI: 10.1021/acs.analchem.4c06076

Yu-Sheng Chen, Hirotsugu Hiramatsu

The combination of chromatography and Raman spectroscopy is challenging because the eluate flows fast and limits the accumulation time of weak Raman signals. The total reflection of light in a liquid core waveguide (LCW) can enhance the Raman signal intensity and thus solve this problem. We used a vertical flow technique to form an LCW with a sample solution and combined Raman spectroscopy with hydrophilic liquid chromatography (HILIC). Additional techniques were used to eliminate the strong Raman signals attributed to the organic solvent used for HILIC. We report the HILIC-Raman analysis of five sugars (fructose, glucose, sucrose, maltose, and trehalose). These sugars were eluted over 11 min (fructose at 36.5 min and trehalose at 47.4 min) and identified by checking the Raman spectra. The limit of detection (LOD) was 60–80 μg mL^–1. The HILIC-Raman technique was also applied to analyze the sugar content of honey. The content of fructose, glucose, and sucrose in wt % was determined to be 39.9 ± 0.6, 26.5 ± 1.8, and 0.9 ± 0.5, respectively, and these values agreed with those determined using LC with the refractive index detector. The HILIC-Raman technique offers a novel approach of the quantitative analysis of solutes in the LC eluate.

色谱和拉曼光谱的结合是具有挑战性的，因为洗脱液流动快，限制了弱拉曼信号的积累时间。光在液芯波导中的全反射可以增强拉曼信号强度，从而解决这一问题。我们使用垂直流动技术与样品溶液形成LCW，并将拉曼光谱与亲水液相色谱（HILIC）相结合。另外还使用了一些技术来消除由于用于HILIC的有机溶剂而产生的强拉曼信号。我们报告了五种糖（果糖、葡萄糖、蔗糖、麦芽糖和海藻糖）的HILIC-Raman分析。这些糖在11分钟内洗脱（果糖36.5分钟，海藻糖47.4分钟），并通过检查拉曼光谱进行鉴定。检出限（LOD）为60 ~ 80 μ mL-1。利用HILIC-Raman技术分析了蜂蜜的含糖量。果糖、葡萄糖和蔗糖在wt %中的含量分别为39.9±0.6、26.5±1.8和0.9±0.5，与LC与折射率检测器测定的值一致。HILIC-Raman技术为LC洗脱液中溶质的定量分析提供了一种新的方法。

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引用次数: 0

The Impact of Molecular Symmetry and Rigidity on the Selective Analysis of VOCs by Mid-IR Laser Spectroscopy 分子对称性和刚性对中红外激光光谱选择性分析挥发性有机化合物的影响

IF 7.4 1区化学 Q1 CHEMISTRY, ANALYTICAL

Analytical Chemistry

Pub Date : 2025-06-14 DOI: 10.1021/acs.analchem.5c02084

Miloš Selaković, Renato Zenobi, Lukas Emmenegger, Béla Tuzson

This study highlights the potential of mid-infrared laser absorption spectroscopy (LAS) for analyzing volatile organic compounds (VOCs) in the gas phase. Using a Vernier-type quantum cascade laser (QCL) in the 9–10 μm spectral region, over 40 different VOCs were systematically investigated with a spectral resolution better than 0.005 cm^–1. It was found that many VOCs, even with more than six heavy atoms, can exhibit significant spectral features at ambient temperature and pressures above 10 mbar, i.e., at conditions well suited for routine analysis. Our observations suggest that in addition to molecular weight and number of atoms, molecular rigidity and symmetry have a decisive impact on the spectral feature content. The high spectral feature content observed in rigid molecules is related to their small number of conformers, while higher molecular symmetry results in fewer nondegenerate vibrational modes, principal rotational axes with different moments of inertia, and a reduced number of nonidentical conformers. Overall, this leads to distinct spectral features that enable the selective and sensitive detection of large VOCs by high-resolution LAS.

这项研究强调了中红外激光吸收光谱（LAS）在分析气相挥发性有机化合物（VOCs）方面的潜力。利用游标型量子级联激光器（QCL）在9-10 μm光谱区对40多种不同的挥发性有机化合物进行了系统的研究，光谱分辨率优于0.005 cm-1。研究发现，许多挥发性有机化合物，即使有超过6个重原子，在环境温度和高于10毫巴的压力下，也就是在非常适合常规分析的条件下，可以表现出显著的光谱特征。我们的观察表明，除了分子量和原子数外，分子的刚性和对称性对光谱特征含量有决定性的影响。在刚性分子中观察到的高光谱特征含量与其较少的构象有关，而较高的分子对称性导致了较少的非简并振动模式、不同转动惯量的主旋转轴和较少的不相同的构象。总的来说，这导致了不同的光谱特征，使高分辨率LAS能够选择性和灵敏地检测大型VOCs。

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引用次数: 0

In-Line Enrichment of Cancer Cells from Whole Blood by Cell Self-Organization in Acoustic Fields 利用细胞自组织在声场中在线富集全血癌细胞

IF 7.4 1区化学 Q1 CHEMISTRY, ANALYTICAL

Analytical Chemistry

Pub Date : 2025-06-13 DOI: 10.1021/acs.analchem.5c01459

Richard Soller, Ola Jakobsson, Per Augustsson

We present a novel method for in-line acoustofluidic separation of cancer cells directly from whole blood. We report for the first time the observation that blood cells can self-organize when packed closely together in an acoustic field. We utilize this effect to enrich K-562 cancer cells and white blood cell subpopulations from whole blood at normal hematocrit levels. Further, we investigate the effect of self-organization of particles and cells with different sizes and acoustic properties. We propose that the mechanism for the phenomenon is based on the change of sign of the acoustic contrast of cancer cells relative to the densely packed red blood cells such that they are pushed to the RBC–plasma interface. This method may be useful as a rapid and gentle initial refinement stage for accessing rare cells, potentially enhancing point-of-care diagnostics and advancing treatments like immunotherapy.

我们提出了一种直接从全血中在线声流分离癌细胞的新方法。我们首次报道了血细胞在声场中紧密聚集时可以自组织的观察结果。我们利用这一效应在正常血细胞比容水平下富集全血中的K-562癌细胞和白细胞亚群。此外，我们还研究了不同大小和声学特性的粒子和细胞的自组织效应。我们提出，这种现象的机制是基于癌细胞相对于密集堆积的红细胞的声学对比符号的变化，使它们被推到红细胞-血浆界面。这种方法可以作为获取稀有细胞的快速和温和的初始改进阶段，潜在地增强即时诊断和推进免疫疗法等治疗。

引用次数: 0

Label-Free Quantification of Apoptosis and Necrosis Using Stimulated Raman Scattering Microscopy 利用受激拉曼散射显微镜无标记定量细胞凋亡和坏死

IF 7.4 1区化学 Q1 CHEMISTRY, ANALYTICAL

Analytical Chemistry

Pub Date : 2025-06-13 DOI: 10.1021/acs.analchem.5c01279

Shivam Mahapatra, Shreya B. Shivpuje, Helen C. Campbell, Boyong Wan, Justin Lomont, Bin Dong, Seohee Ma, Karsten J. Mohn, Chi Zhang

Recombinant proteins are critical for modern therapeutics and diagnostics, with Chinese hamster ovary (CHO) cells serving as the primary production platform. However, environmental and chemical stressors in bioreactors often trigger cell death, particularly apoptosis, posing a significant challenge to recombinant protein manufacturing. Rapid, label-free methods to monitor cell death are essential for ensuring better production quality. Stimulated Raman scattering (SRS) microscopy offers a powerful, label-free approach to measure lipid and protein compositions in live cells. We demonstrate that SRS microscopy enables rapid and reagent-free analysis of apoptotic and necrotic transitions. Our results show that apoptotic cells exhibit higher protein concentrations, while necrotic cells show an opposite trend. To enhance analysis, we developed a quantitative single-cell analysis pipeline that extracts chemotypic and phenotypic signatures of apoptosis and necrosis, enabling the identification of subpopulations with varied responses to stressors or treatments. Furthermore, the cell death analysis was successfully generalized to other stressors and cell types. This study highlights SRS microscopy as a robust and noninvasive tool for rapid monitoring of live cell apoptotic and necrotic transitions. Our method and findings hold potential for improving quality control in CHO cell-based biopharmaceutical production and for evaluating cell death in diverse biological contexts.

重组蛋白在现代治疗和诊断中至关重要，中国仓鼠卵巢（CHO）细胞是主要的生产平台。然而，生物反应器中的环境和化学应激源经常引发细胞死亡，特别是细胞凋亡，这对重组蛋白的制造提出了重大挑战。快速、无标签监测细胞死亡的方法对于确保更好的生产质量至关重要。受激拉曼散射（SRS）显微镜提供了一种强大的，无标记的方法来测量活细胞中的脂质和蛋白质组成。我们证明SRS显微镜能够快速和无试剂分析细胞凋亡和坏死转变。我们的研究结果表明，凋亡细胞表现出更高的蛋白质浓度，而坏死细胞则表现出相反的趋势。为了加强分析，我们开发了一种定量的单细胞分析管道，提取细胞凋亡和坏死的化学型和表型特征，从而能够识别对应激源或治疗有不同反应的亚群。此外，细胞死亡分析成功地推广到其他应激源和细胞类型。这项研究强调了SRS显微镜作为一种强大的、无创的工具，用于快速监测活细胞凋亡和坏死转变。我们的方法和发现对于提高CHO细胞为基础的生物制药生产的质量控制和评估不同生物环境下的细胞死亡具有潜力。

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引用次数: 0

A Programmable Dynamic Range Electrochemiluminescence Platform with Dual-Signal Output and Single Luminophore, Utilizing Polyadenine-Anchored Triblock DNA 利用聚腺嘌呤锚定的三块DNA，具有双信号输出和单发光团的可编程动态范围电化学发光平台

IF 7.4 1区化学 Q1 CHEMISTRY, ANALYTICAL

Analytical Chemistry

Pub Date : 2025-06-13 DOI: 10.1021/acs.analchem.5c00866

Yang Jiang, Chunjia Ren, Yanxia Qiao, Shengtao Zhang, Jiayue Shi, Xia Yang, Sijia Li, Yaqian Zhou, Yan Li

Rational design of nucleic acid capture probes to modulate binding affinity is a valuable strategy for programing the dynamic range and limit of detection (LOD) in electrochemiluminescence (ECL) assays. Current strategies, however, have scarcely achieved this expectation. We present a binding affinity-driven, dynamic range, and LOD programmable triblock DNA-based dual-signal ECL platform for the nucleic acid assay. The probe architecture features a polyadenine (polyA) sequence that positions two flanking, partially complementary strands on a gold electrode with their lateral spacing precisely engineered to regulate target binding affinity. Remarkably, this system generates a dual-signal output from a single ECL luminophore─tris(2,2′-bipyridine)ruthenium(II) (Ru(bpy)₃²⁺)─where target-induced conformational changes alter the Ru(bpy)₃²⁺ distance from the electrode surface, thereby triggering distinct ECL generation mechanisms at separate electrochemical potentials. And this dual-signal output enables ratiometric or multi-target assays. This integrated platform features programmable dynamic range and LOD, single recognition element, and dual-signal output with single ECL luminophore, potentially presenting a new approach to advanced ECL nucleic acid sensing platforms.

合理设计核酸捕获探针来调节结合亲和性是制定电化学发光（ECL）检测动态范围和检出限（LOD）的重要策略。然而，目前的战略几乎没有达到这一期望。我们提出了一个结合亲和力驱动的、动态范围的、LOD可编程的基于三块dna的双信号ECL平台，用于核酸检测。探针结构具有聚腺嘌呤（polyA）序列，该序列将两个侧翼部分互补的链定位在金电极上，其横向间距精确设计以调节目标结合亲和力。值得注意的是，该系统从单个ECL发光团产生双信号输出─tris（2,2 ' -联吡啶）钌（II）（Ru(bpy)32+）─其中靶诱导的构象变化改变了Ru(bpy)32+与电极表面的距离，从而在不同的电化学电位下触发不同的ECL生成机制。这种双信号输出使比率或多目标分析成为可能。该集成平台具有可编程动态范围和LOD，单个识别元件和双信号输出，单个ECL发光团，可能为先进的ECL核酸传感平台提供新的途径。

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引用次数: 0

Controllable Ion-Repulsion Enables Rapid and Trace-Level Detection of Hydrophobic Sulfonylurea Herbicides with ICPMS/MS without the Organic Mode 可控离子斥力实现了无需有机模式的ICPMS/MS快速痕量检测疏水磺酰脲类除草剂

IF 7.4 1区化学 Q1 CHEMISTRY, ANALYTICAL

Analytical Chemistry

Pub Date : 2025-06-13 DOI: 10.1021/acs.analchem.5c01663

Bassam Lajin, Walter Goessler

The inductively coupled plasma tandem mass spectrometry (ICPMS/MS) is emerging as a detector for compounds tagged with a nonmetal, but can be hampered by poor compatibility with organic eluents. Herein, we describe an alternative approach to using high fractions of organic solvents for the detection of hydrophobic compounds while presenting a novel sulfur speciation application involving the determination of a common and widely used class of hydrophobic sulfonylurea herbicides. The approach is based on controllable retention using an ion-repulsion concept, and it is shown that this approach enables minimizing the amount of organic eluent needed for speciation analysis, eliminating the need for the organic ICPMS mode and therefore achieving uncompromised sensitivity. The applied approach enabled fast analysis within 8 min with a mobile phase containing as little as 10% methanol. The limit of detection was 0.3 μg S L^–1 (injection volume 20 μL), which is on par with the lowest achievable LOD for sulfur speciation with ICPMS/MS detection, highlighting the utility of the ion-repulsion approach in overcoming the current limitations of the organic ICPMS mode commonly used with ICPMS detection. Spiking experiments showed the developed method to be directly applicable to a river water matrix with no need for sample preparation or internal standards unlike currently used methods based on ESIMS/MS detection. The ion-repulsion concept is generally applicable to speciation analysis with ICPMS detection for ionizable analytes, provides similar control over retention to organic solvents, and aids in avoiding the limitations of the organic ICPMS mode.

电感耦合等离子体串联质谱（ICPMS/MS）作为非金属标记化合物的检测器正在兴起，但由于与有机洗脱液的相容性差而受到阻碍。在此，我们描述了一种使用高分数有机溶剂检测疏水化合物的替代方法，同时提出了一种新的硫形态应用，涉及测定常见且广泛使用的疏水磺酰脲类除草剂。该方法基于使用离子排斥概念的可控保留，并且表明该方法可以最大限度地减少物种形成分析所需的有机洗脱液的量，从而消除了对有机ICPMS模式的需求，从而实现了不受影响的灵敏度。应用的方法可以在8分钟内快速分析，流动相中甲醇含量仅为10%。检出限为0.3 μ S L-1（进样量为20 μL），与ICPMS/MS检测硫形态的最低检出限相当，突出了离子排斥方法在克服当前ICPMS检测常用的有机ICPMS模式的局限性方面的实用价值。实验结果表明，该方法与现有的基于ESIMS/MS检测的方法不同，不需要样品制备或内部标准，直接适用于河流水基质。离子排斥概念通常适用于可电离分析物的ICPMS检测的物种形成分析，提供了对有机溶剂保留的类似控制，并有助于避免有机ICPMS模式的局限性。

{"title":"Controllable Ion-Repulsion Enables Rapid and Trace-Level Detection of Hydrophobic Sulfonylurea Herbicides with ICPMS/MS without the Organic Mode","authors":"Bassam Lajin, Walter Goessler","doi":"10.1021/acs.analchem.5c01663","DOIUrl":"https://doi.org/10.1021/acs.analchem.5c01663","url":null,"abstract":"The inductively coupled plasma tandem mass spectrometry (ICPMS/MS) is emerging as a detector for compounds tagged with a nonmetal, but can be hampered by poor compatibility with organic eluents. Herein, we describe an alternative approach to using high fractions of organic solvents for the detection of hydrophobic compounds while presenting a novel sulfur speciation application involving the determination of a common and widely used class of hydrophobic sulfonylurea herbicides. The approach is based on controllable retention using an ion-repulsion concept, and it is shown that this approach enables minimizing the amount of organic eluent needed for speciation analysis, eliminating the need for the organic ICPMS mode and therefore achieving uncompromised sensitivity. The applied approach enabled fast analysis within 8 min with a mobile phase containing as little as 10% methanol. The limit of detection was 0.3 μg S L–1 (injection volume 20 μL), which is on par with the lowest achievable LOD for sulfur speciation with ICPMS/MS detection, highlighting the utility of the ion-repulsion approach in overcoming the current limitations of the organic ICPMS mode commonly used with ICPMS detection. Spiking experiments showed the developed method to be directly applicable to a river water matrix with no need for sample preparation or internal standards unlike currently used methods based on ESIMS/MS detection. The ion-repulsion concept is generally applicable to speciation analysis with ICPMS detection for ionizable analytes, provides similar control over retention to organic solvents, and aids in avoiding the limitations of the organic ICPMS mode.","PeriodicalId":27,"journal":{"name":"Analytical Chemistry","volume":"593 1","pages":""},"PeriodicalIF":7.4,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144288515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Improving Regions of Interest Multivariate Curve Resolution: Development of an Empirical Metric System through the Study of Passive Sampling Extracts of Wastewater in Antarctica. 提高感兴趣区域多元曲线分辨率：通过对南极洲废水被动采样提取物的研究开发经验度量系统。

IF 6.7 1区化学 Q1 CHEMISTRY, ANALYTICAL

Analytical Chemistry

Pub Date : 2025-06-13 DOI: 10.1021/acs.analchem.5c00777

Barbara Benedetti, Carlos Perez-Lopez, Henry MacKeown, Emanuele Magi, Roma Tauler

The huge potential of liquid chromatography-high-resolution mass spectrometry (LC-HRMS) still comes along with the challenges of data analysis. Regions of interest multivariate curve resolution (ROIMCR) is a valid chemometric tool when working in data-independent acquisition (DIA), since it provides a link between precursor and product ions based on chromatographic and spectral profiles. Still, the quality of the ROIMCR models should be carefully evaluated for a consequent reliable annotation of non-target chemicals. The present case study deals with the non-target analysis of extracts coming from passive samplers deployed in a wastewater treatment facility in Antarctica (Italian Research Station). The extracts, derived from polar organic chemical integrative samplers (POCIS), were analyzed by LC-DIA-HRMS/MS, resulting in a rich and complex data set. The use of a fit-for-purpose ROIMCR workflow ended in six models for a total of 770 resolved components; among them, approximately 100 compounds were tentatively identified thanks to the recently developed MSident software, including pharmaceuticals and natural substances. The chemical meaningfulness of all resolved MCR components was carefully checked and rationalized for the first time in a classification system, with 7 classes divided into 3 "goodness levels" (A, B, and C). Level A components were characterized by single chromatographic peaks and mass spectra with a reasonable appearance of precursor and product ions. Level B components presented flaws or anomalies in either the chromatographic or spectral profile, and level C components clearly showed unacceptable features. The percentage of high-quality MCR components (level A) ranged from 15 to 48%, while components of acceptable quality (levels A and B) reached percentages between 65% and 85%. Most annotated compounds were indeed associated with good-quality MCR components. The automatization of the proposed classification system may constitute a powerful additional tool to evaluate MCR models' quality and thus improve the reliability of ROIMCR results when applied to challenging case studies.

液相色谱-高分辨率质谱（LC-HRMS）的巨大潜力仍然伴随着数据分析的挑战。多变量曲线分辨率（ROIMCR）在数据独立采集（DIA）中是一种有效的化学计量工具，因为它提供了基于色谱和光谱剖面的前体离子和产物离子之间的联系。尽管如此，应该仔细评估ROIMCR模型的质量，以便对非目标化学品进行可靠的注释。本案例研究涉及对部署在南极洲一个污水处理设施（意大利研究站）的被动采样器提取物的非目标分析。采用LC-DIA-HRMS/MS对极性有机化学综合采样器（POCIS）提取物进行了分析，得到了丰富而复杂的数据集。适合用途的ROIMCR工作流程的使用结束于共770个已解决组件的6个模型；其中，通过最近开发的MSident软件，初步确定了药物和天然物质等100多种化合物。所有溶解的MCR成分的化学意义被仔细检查并首次在分类系统中合理化，7个类别分为3个“良好水平”（a， B和C）。A级组分通过单峰色谱和质谱表征，前驱体和产物离子形态合理。B级组分在色谱或光谱剖面上都存在缺陷或异常，C级组分明显表现出不可接受的特征。高质量MCR组件（A级）的百分比在15%到48%之间，而可接受质量组件（A级和B级）的百分比在65%到85%之间。大多数注释的化合物确实与高质量的MCR成分相关。所提出的分类系统的自动化可能构成一个强大的附加工具来评估MCR模型的质量，从而在应用于具有挑战性的案例研究时提高ROIMCR结果的可靠性。

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引用次数: 0

A Real-Time Enzyme-Linked Aptamer Assay (RT-eELAA) for Rapid and Sensitive Detection of Viral Antigens in Saliva Using Electrochemical Readout. 实时酶联适体测定（RT-eELAA）用于快速、灵敏地检测唾液中的病毒抗原。

IF 6.7 1区化学 Q1 CHEMISTRY, ANALYTICAL

Analytical Chemistry

Pub Date : 2025-06-13 DOI: 10.1021/acs.analchem.5c02555

Bal Ram Adhikari, Qing Wang, Jiuxing Li, Payel Sen, Zijie Zhang, Jimmy Gu, Bruno J Salena, Deborah Yamamura, Yingfu Li, Leyla Soleymani

Despite the need for reliable rapid antigen tests for infectious disease diagnostics, tests that combine rapid answer-to-result times with high sensitivity and specificity remain elusive. A major challenge in developing such tests is the loss of performance of analytical assays in clinical samples. Herein, we developed a rapid antigen test based on a real-time electrochemical sandwich assay for detecting SARS-CoV-2 and Influenza A in saliva. This assay used aptamers for both target capture and signal transduction and produced limits of detection of 301 and 743 copies/mL for SARS-CoV-2 and Influenza A, respectively. When evaluating this assay with clinical saliva samples, we encountered major issues in distinguishing between positive and negative samples. In response, we developed a revised method to interrogate each clinical sample with a pair of electrochemical detectors modified, respectively, with a functional aptamer or a nonfunctional aptamer mutant. This method enabled us to normalize the signal response measured from each clinical sample with a reference signal, overcoming the previously encountered challenge and resulting in a clinical sensitivity of 100% and a specificity of 100% when analyzing 20 saliva samples that were collected and tested for COVID-19.

尽管传染病诊断需要可靠的快速抗原检测，但结合快速回答-结果时间与高灵敏度和特异性的检测仍然难以实现。开发这类测试的一个主要挑战是临床样品分析分析性能的丧失。在此，我们开发了一种基于实时电化学三明治法的快速抗原检测方法，用于检测唾液中的SARS-CoV-2和甲型流感。该试验使用了靶捕获和信号转导的适体，对SARS-CoV-2和甲型流感分别产生了301和743拷贝/mL的检测限。当对临床唾液样本进行评估时，我们遇到了区分阳性和阴性样本的主要问题。作为回应，我们开发了一种改进的方法，用一对电化学探测器分别用功能适配体或非功能适配体突变体修饰来询问每个临床样品。该方法使我们能够用参考信号对每个临床样本测量的信号响应进行归一化，克服了之前遇到的挑战，并在分析收集和检测的20份COVID-19唾液样本时获得了100%的临床敏感性和100%的特异性。

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引用次数: 0

Active Learning Improves Ionization Efficiency Predictions and Quantification in Nontargeted LC/HRMS 主动学习改善非靶向LC/HRMS的电离效率预测和量化

IF 7.4 1区化学 Q1 CHEMISTRY, ANALYTICAL

Analytical Chemistry

Pub Date : 2025-06-13 DOI: 10.1021/acs.analchem.5c00816

Wei-Chieh Wang, Nahid Amini, Carolin Huber, Meelis Kull, Anneli Kruve

Liquid chromatography electrospray ionization high-resolution mass spectrometry (LC/ESI/HRMS) is frequently employed in nontargeted screening (NTS) due to its high selectivity and sensitivity. However, data interpretation is challenging since the number of chemical standards available for quantification is limited and the response of the chemicals vastly differs depending on their structure and analysis conditions. Therefore, machine learning (ML) models have been utilized to predict ionization efficiency (IE) and enable the quantification of detected chemicals. It has been observed that the error in the predictions is high for chemicals structurally different from the training data. To enlarge the training set and to accurately predict the IE given a limited labeling budget, active learning (AL) is proposed to acquire informative data points from the targeted chemical space. In the current study, four AL approaches (clustering-based, uncertainty-based, mix, and anticlustering) and a baseline approach (random) were evaluated for IE prediction. The RMSE of the IE in the targeted space dropped significantly (up to 0.3 log units) after a single AL iteration, highlighting the necessity of chemical space exploration before ML model execution. Clustering-based AL reduced the RMSE least, while the uncertainty-based AL was inefficient if ten or more chemicals were sampled in one iteration, thereby reducing its practicality. Finally, expanding the chemical space improved the quantification accuracy from a fold error of 4.13× to 2.94× for five natural products in Alpinia officinarum, thereby demonstrating the need for updating the chemical space coverage of the training set.

液相色谱电喷雾电离高分辨率质谱法（LC/ESI/HRMS）因其高选择性和高灵敏度而被广泛应用于非靶向筛选（NTS）。然而，数据解释是具有挑战性的，因为可用于量化的化学标准的数量有限，化学物质的反应因其结构和分析条件的不同而有很大差异。因此，机器学习（ML）模型已被用于预测电离效率（IE）并使检测到的化学物质能够量化。已经观察到，对于结构上与训练数据不同的化学物质，预测误差很高。为了扩大训练集并在有限的标注预算下准确地预测IE，提出了主动学习（AL）从目标化学空间中获取信息数据点。在目前的研究中，评估了四种人工智能方法（基于聚类、基于不确定性、混合和反聚类）和基线方法（随机）用于IE预测。经过一次人工智能迭代后，目标空间中IE的RMSE显著下降（高达0.3 log单位），突出了在ML模型执行之前进行化学空间探索的必要性。基于聚类的人工智能降低RMSE最小，而基于不确定性的人工智能在一次迭代中采样十种或更多化学物质时效率低，从而降低了其实用性。最后，通过扩大化学空间，将小檗中5种天然产物的量化精度从4.13×的倍误差提高到2.94×，从而表明需要更新训练集的化学空间覆盖率。

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引用次数: 0

Localized Surface Plasmon Resonance-Mediated Fabry-Pérot Interferometer for Enzyme-Free Glucose Detection. 局域表面等离子体共振介导的无酶葡萄糖检测法布里-普氏干涉仪。

IF 6.7 1区化学 Q1 CHEMISTRY, ANALYTICAL

Analytical Chemistry

Pub Date : 2025-06-13 DOI: 10.1021/acs.analchem.5c02134

Hairihan Zhou, Yue Zhang, Yueyang Zhang, Yinde Wu, Chenxi Zhao, Zhida Gao, Pei Song, Yan-Yan Song, Xiaona Li

The well-known Fabry-Pérot (F-P) cavity serves as a crucial element of complex optical devices, offering distinctive functionalities. However, modifying reflection properties by altering the underlying optical structure remains challenging. Inspired by the optical modulation ability of plasmonic nanoparticles (NPs) and the sensitivity of reflective interferometric Fourier transform spectroscopy (RIFTS) of the F-P cavity to effective optical thickness (EOT), herein, a local surface plasmon resonance (LSPR) effect-mediated F-P interferometer with improved sensing ability is proposed. Using glucose as a model analyte, the TiO₂ nanotube (NT)-based F-P interferometer is constructed by integrating a pH-responsive block copolymer (BCP) film and LSPR-mediated enzyme-like reactions in interferometric TiO₂ NTs. The high-energy hotspots generated by the Au-LSPR effect can accelerate glucose oxidation in NTs, which generates gluconic acid and H₂O₂ as the products. By combining the experimental results with COMSOL simulations, it is found that the satisfactory response achieved in reflective interferometric Fourier transform spectroscopy (RIFTS) not only relates to the enhanced reflectivity induced by AuNPs but also depends on the EOT changes mediated by the Au-LSPR effect. The plasmon-mediated F-P interferometer offers sensitive glucose quantification with satisfactory performance in real samples, suggesting a new route to design an F-P cavity with a highly sensitive response for boosting target sensing performance.

著名的法布里-帕姆罗（F-P）腔是复杂光学器件的关键元件，具有独特的功能。然而，通过改变底层光学结构来改变反射特性仍然具有挑战性。利用等离子体纳米粒子（NPs）的光学调制能力和F-P腔反射干涉傅立叶变换光谱（RIFTS）对有效光学厚度（EOT）的敏感性，提出了一种提高传感能力的局部表面等离子体共振（LSPR）效应介导的F-P干涉仪。以葡萄糖为模型分析物，将ph响应嵌段共聚物（BCP）膜和lspr介导的酶样反应整合到TiO2纳米管（NT）干涉仪中，构建了TiO2纳米管F-P干涉仪。Au-LSPR效应产生的高能热点可以加速NTs中的葡萄糖氧化，生成葡萄糖酸和H2O2作为产物。将实验结果与COMSOL模拟结果相结合，发现反射干涉傅立叶变换光谱（RIFTS）获得满意的响应不仅与AuNPs诱导的反射率增强有关，还取决于Au-LSPR效应介导的EOT变化。等离子体介导的F-P干涉仪在实际样品中提供了令人满意的灵敏葡萄糖定量，为设计具有高灵敏度响应的F-P腔提供了一条新的途径，以提高目标传感性能。

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引用次数: 0