ANALYTICA CHIMICA ACTA

High-precision analysis of toxic metals in lithium-ion battery materials across various complex media
Qi T, Yang X, Liu Y, Wen H, Liu F, Yue Z, Qi Z, Zhang H, Fu J, Liu Q and Jiang G
Present regulations regarding the management and recycling of spent Lithium-ion batteries (LIBs) are inadequate, which may lead to the pollution of lithium (Li) and heavy metals in water and soil during the informal disposal of such batteries. To comprehend the distribution of toxic metals within spent LIBs and contaminated environmental media, precise analytical methods for toxic metals in these materials are crucial. However, due to the chemical complexity of LIBs materials (e.g., lithium iron phosphate, graphite, separators, and electrolytes), there is still a lack of research on developing and validating analytical techniques for toxic metals in LIB materials across various environmental media.
Hierarchically porous covalent organic framework doped monolithic column for on-line chip-based array microextraction of nonsteroidal anti-inflammatory drugs in microlitre volume of blood
Zhang Q, Chen B, He M and Hu B
Traditional blood drug analysis involves large blood consumption and complicated operations and a further reduction in blood consumption is urgently needed. Chip-based monolithic column microextraction is a good strategy for the pretreatment of small-volume samples, and new monolithic materials is the critical factor. Covalent organic frameworks (COFs) are good adsorbents due to large specific surface area and rich conjugated structure. However, the poor dispersion ability of COFs in prepolymer solution severely hinders the preparation of COFs doped monolithic columns. Herein, high internal phase emulsion with viscoelastic properties was adopted to fixed COF particles.
Integrated strategy for high-confident global profiling of the histidine phosphoproteome
Li S, Li L, Ma M, Xing M, Qian X and Ying W
Histidine phosphorylation (pHis) plays a key role in signal transduction in prokaryotes and regulates tumour initiation and progression in mammals. However, the pHis substrates and their functions are rarely known due to the lack of effective analytical strategies.
Towards high throughput analysis using 96-well plate solid phase extraction to determine sedatives and β-blocker residues in food control monitoring
Arrizabalaga-Larrañaga A, van Doorn D and Sterk SS
Veterinary drugs are widely used in animal production to prevent infections and treat diseases but, this may cause a risk to consumers. Due to the high number of food samples required to monitor yearly, simple, fast, sensitive and selective analytical methods are needed in control laboratories to ensure consumers safety. Nevertheless, many analytical methodologies available in these laboratories include multiple steps and therefore are time-consuming and hinder the analysis throughput requiring significant amounts of solvents and reagents.
Analysis of deliquescent chloride salt by laser-induced breakdown spectroscopy with controlled uniform precipitation
Kang L, Chen J, Huang Z, Lin Z, Zhang R, Lu B and Li X
The electrolytic efficiency in magnesium (Mg) production by molten salt electrolysis is mainly affected by the chloride content, which is determined by the metal content in the cooled molten salt. Laser-induced breakdown spectroscopy (LIBS) is a potential element detection method in cooled molten salt element detection. However, the cooled molten chloride salt is easily deliquescent, which greatly affects the LIBS detection results.
Microwave-assisted extraction of polysaccharides from Micromelum minutum leaves using citric acid monohydrate-glycerol based deep eutectic solvents and evaluation of biological activities
Md Yusoff MH and Shafie MH
The extraction of polysaccharides using an acidic extraction media has been extensively reported, highlighting its effectiveness in yielding high-quality polysaccharides. A higher concentration of acidic solution could hydrolyze the structure of polysaccharide, while a low concentration reduces the extraction efficiency. Despite this challenges, deep eutectic solvents (DES) were introduced as an alternative extraction medium due to additional interactions such as inter and intra-molecular interactions, Van de Waals, hydrogen bond, and electrostatic interactions, which could improve the polysaccharide extraction efficiency and biological activities. Furthermore, the extraction conditions such as extraction medium and extraction parameters could affect the properties of polysaccharides as well as influence their structure-activity relationship for biological activities.
Residence time prediction in magnetically controlled biomolecular local rebinding-dissociation kinetics
Zuo C, Wen Y, Chen D, Ouyang J and Li P
The residence time of drug-target conjugates is a critical factor in drug screening and efficacy prediction. The local rebinding-dissociation kinetics gives insights into in-vivo drug-target interactions. A magnetic torque system (MTS) is designed to observe rebinding-dissociation kinetics for predicting residence time. The system utilizes an alternating magnetic field (AMF) to manipulate the magnetization motion of magnetically labeled biomolecules and the forces acting upon biomolecular bonds. The motion, sensed by a quartz crystal microbalance (QCM), reflects biomolecular interactions occurring at the particle surface. Meanwhile, the motion facilitates the separation of dissociated molecules from the surface, thereby obviating the necessity for fixed and mobile phases in common kinetics observations. The constant and static solution environment minimizes reagent consumption. The MTS was utilized to observe the local rebinding-dissociation of antibodies (PAB and MAB) to magnetic beads (MB) and to HER2 receptors. The residence times recorded by the MTS were larger than the results obtained via SPR method, due to the occurrences of rebinding-dissociation kinetics. Interaction behaviours can be meticulously regulated for varying affinities by modulating the intensity of magnetic field. A high intensity field (400 Oe) was applied for strong binding between antibody-MB (biotin-streptavidin), and a low intensity field (300 Oe) was applied for weak antigen-antibody interactions. An increase in AMF strength enhanced dissociation, with a shift from 300 Oe to 400 Oe resulting in a 1 ∼ 4-fold reduction in residence time. Overall, the MTS provides an interactive and customizable perspective on kinetics observations.
Metal-to-particle charge transfer invoked photoelectrochemistry on ferroelectric SrTiO for split-mode and high-throughput aptasensing
Zhang Q, Gu M, Zhang L, Wu X and Wang GL
Split-mode aptasensing is highly desirable in photoelectrochemistry because of its distinctive advantages of high-throughput, avoided damage to biomolecules, and increased sensitivity and selectivity. However, the currently available photoelectrochemical (PEC) strategy conducible to split-mode aptasensing is still limited to the bioreaction mediated generation of photoactive species, in which a low photocurrent was usually attained, rending this strategy impotent for attaining high sensitivity. As a result, to explore new strategies that are amendable to highly efficient, split-mode PEC aptasensing are still challenging but demanding. Herein, ferrocyanide mediated metal-to-particle charge transition (MPCT) on ferroelectric strontium titanate (SrTiO) was explored as an innovative signal transduction strategy and was validated for high-performance aptasensing. By taking the 17β-Estradiol (E2) as a model analyte, the recognition between the target (E2) and its aptamer anchored on the FeO@Au (named as FeO@Au/Apt) destroyed the beforehand formed assembly between the FeO@Au/Apt and the ssDNA labeled liposome encapsulated with [Fe(CN)] (named as DLL-FeCN), which resulted in the release of the beforehand encapsulated [Fe(CN)] into solution. The released [Fe(CN)] then coordinated onto the surface of SrTiO nanoparticles consisted photoelectrode, forming the MPCT process from metal ion (iron (II) in [Fe(CN)]) to the conduction band (CB) of SrTiO for anodic photocurrent signal output. The detection achieved linear range of 1.0 pM-100 nM, with a detection limit of 0.3 pM for E2. Benefiting from the cooperative effects of the MPCT process and the ferroelectric polarization in bulk SrTiO for achieving highly efficient photocurrent generation capability, the developed split-type detection had the advantage of high sensitivity/selectivity and high throughput. This work not only opens up the MPCT process for innovative PEC sensing strategy but also blazes a new road for high performance PEC aptasensing.
Zwitterionic covalent organic nanosheets for selective analysis of domoic acid in marine environment
Xu J, Yu Z, Zhang W, Xie S, Liao B and Zhang L
Domoic acid (DA) is a neurotoxic compound causing amnesic shellfish poisoning, secreted by red algae and diatoms. As a glutamate analogue, DA accumulates in filter-feeding marine organisms, posing significant health risks to humans upon consumption. Detecting DA in marine environments remains challenging due to its low concentration and interference from complex matrices. Effective detection and removal require materials with high efficiency and selectivity, which traditional inorganic ionic materials lack due to their limited adsorption capacity and selectivity. Ionic covalent organic frameworks (iCOFs) expected to become highly efficient DA adsorbents due to tunable ionic sites.
Microcolumn and coelution hydration of oil seal blood spot for efficient screening of newborn α-thalassemia via chip isoelectric focusing
Zha G, Xiao X, Tian Y, Zhu H, Chen P, Zhang Q, Yu C, Li H, Wang Y and Cao C
The global prevalence of α-thalassemia necessitates effective newborn screening strategies due to its severe clinical consequences. Traditional methods such as liquid chromatography (LC), capillary electrophoresis (CE), and isoelectric focusing (IEF) face limitations, including low separation efficiency, poor sensitivity for detecting Hb Bart's, and time-intensive operations, particularly with dried blood spots (DBS). These limitations hinder timely and accurate screening. This study addresses the need for a more efficient, sensitive, and rapid method for detecting Hb Bart's in newborns.
Synthesis of a novel β-cyclodextrin chiral stationary phase and its application to the evaluation of the enantioselective bioaccumulation and elimination behavior of tebuconazole in Rana nigromaculata tadpoles
Zheng L, Li M, Jiang Z, Fan J, Fang Z, Zheng J and Cui Y
The increased production and use of chiral pesticides will enhance their exposure in the environment. Chiral pesticides typically exhibit varied biological effects among these enantiomers. Therefore, it is very essential to develop and validate chiral analytical methods to investigate their potential ecological risks from a stereoselective perspective. Current separation of pesticides enantiomers relies extensively on chiral stationary phases (CSPs), while the development of β-Cyclodextrin derivatives CSPs become the research focus due to their great modifiability and excellent chiral recognition capabilities.
Detection of factor Xa activity using giant magnetoresistive biosensors
Lee Y, Kim S, Song TJ, Wang SX and Lee JR
As anticoagulants are widely used to treat patients with atrial fibrillation (AF) and other thrombotic conditions, it is necessary for physicians to determine whether the medication has been taken in emergencies. Among many anticoagulants, rivaroxaban has attracted attention due to its safety and convenience. Since rivaroxaban inhibits activated coagulation factor X (factor Xa), measuring factor Xa activity can determine the presence of rivaroxaban.
A novel near-infrared fluorescent probe for butyrylcholinesterase: Research for screening of natural anti-AD inhibitors
Yin X, Zhang G, Song G, Li X, Liu X, Wang L, Zhang H and Tang Z
Elevated levels of butyrylcholinesterase (BuChE) have the potential to be predictive in the timely detection and diagnosis of Alzheimer's disease (AD). By inhibiting of BuChE activity can raise acetylcholine levels and intervene AD processes. Therefore, BuChE as an important factor in treatment AD has been given more and more attention in clinical studies. Given the facts above, in this study, for precise monitoring of BuChE level changes and screening for possible butyrylcholinesterase inhibitor (BuChEI) for AD diagnosis and therapy, a near-infrared (NIR) fluorescence probe (NFP-BuChE) was created. The probe exhibits excellent sensitivity and selectivity for BuChE. NFP-BuChE has been successfully applied to the detection of endogenous BuChE levels in live cells, and we successfully constructed a screening system for BuChEI on cells and a novel natural efficient BuChEI (matrine) was discovered and identified, which significantly reduced BuChE activity and thus alleviated AD symptoms. Most importantly, for the first time, we measured the changes of BuChE levels in zebrafish (0-4 days) after fertilization, various organs of zebrafish, and AD zebrafish modeled by different concentrations of AlCl by NFP-BuChE, and at the same time, we also validated the inhibitory effect of matrine on BuChE by NFP-BuChE in zebrafish. In addition, NFP-BuChE has also been successfully used to measure the changes of BuChE levels in the brains of AD mice. These findings imply that NFP-BuChE is a potentially useful molecular tool for screening possible natural BuChEI quickly and for monitoring changes in BuChE activity, and it is expected that more value will be explored in mice. In addition, matrine and its derivatives are promising options for future Alzheimer's disease treatments.
Fluorescein-based low-molecular-mass markers of isoelectric point for tracing pH gradient using high sensitivity capillary isoelectric focusing with laser-induced fluorescence detection
Dadajová P, Čmelík R, Šlais K and Duša F
Successful implementation of capillary isoelectric focusing (cIEF) in general requires the use of reference points - markers of isoelectric point. The low-molecular-mass fluorescent compounds based on the fluorescein structure, capable of marking distinct isoelectric points (pIs) with good focusing ability, stability, high extinction coefficient, and fluorescence are an alternative to the peptide and protein pI markers.
Sensitive detection of Hg(II) on MoS/NiS based on interfacial engineering to accelerate the Ni/Ni cycle: Identification the role of atomic-level heterojunction-induced electron transfer in electroanalysis
Xu H, Li HR, Li JY, Qu JJ and Li SS
The valence change of transition metal ions in nanomaterials can highly enhance the electrochemical detection performance toward heavy metal ions (HMIs), and how to further promote the valence change calls enormous concerns in electroanalysis. In this work, an interfacial engineering that combing the MoS and NiS together to form the MoS/NiS complex is proposed. The density functional theory (DFT) results reveals that the novel atomic-level heterojunction between MoS and NiS will build an internal electric field (IEF), which leads to an enhanced conductivity and valence change behavior of Ni atoms in MoS/NiS complex, resulting in a superior detection performance. In detail, the formation of atomic-level heterojunctions in the MoS/NiS complex accelerates electron transfer due to the valence changes associated with Ni/Ni cycling. The active Mo species on MoS act as electron donors, facilitating the reduction of Ni to Ni on NiS, thereby promoting Ni/Ni cycling. As anticipated, the MoS/NiS complex exhibits exceptional detection performance for Hg(II), with a sensitivity of 459.13 μA μM cm, surpassing even that of other composite materials. In general, these findings are expected to significantly advance the application of electron transfer acceleration in electroanalysis based on the construction of heterojunction.
Synergistic enhancement of chemical and electromagnetic effects in a TiCT/AgNPs two-dimensional SERS substrate for ultra-sensitive detection
Li L, Zhang T, Zhang L, Wang G, Huang X, Li W, Wang L, Li Y, Li J and Lu R
It is well established that surface-enhanced Raman scattering (SERS) is one of the most commonly used spectral analysis techniques in real-world applications, including chemical and biological sensing, analytical detection, and even forensics. It offers high sensitivity, high resistance to solvents, photobleaching, and limited spectrum bands. In general, SERS is caused by two mechanisms, the electromagnetic enhancement mechanism (EM) and the chemical enhancement mechanism (CM), although the exact mechanism is not yet known. For increased sensitivity, a SERS substrate based on EM coupled with CM is essential.
Simultaneous determination of somatic cell count and total plate count in raw milk based on ATP bioluminescence assay
Yang L, Sun X, Chen J, Zhang J, Li X, Qu S, Wu K, Huang F and Chen A
The somatic cell count (SCC) and total plate count (TPC) are essential quality indicators for raw milk. Traditional detection methods require separate measurements and rely on complex, large-scale instruments or cultivation techniques, which are both time-consuming and laborious. To address these challenges, this study developed a novel method for the simultaneous detection of SCC and TPC in the same raw milk sample using the ATP bioluminescence assay. This method utilizes oxy-ethylated iso-nonyl phenol (Neonol-10) and cetyltrimethylammonium bromide (CTAB) to selectively lyse somatic cells and microorganisms, respectively. This technique is straightforward to operate and can be completed within 2.5 h, with detection ranges of 1 × 10⁴ to 3 × 10⁶ cells/mL for SCC and 1 × 10⁵ to 5 × 10⁷ CFU/mL for TPC. Importantly, this technique meets the requirements of detection standards in China, European Union, Canada, United States, etc. For SCC or TPC in raw milk. Overall, this innovative approach does not rely on expensive equipment or facilities and the stepwise reagent addition procedure can be easily developed into an automated high-throughput system for rapid on-site testing of SCC and TPC in raw milk.
A ZnO-nanorod/PEDOT:PSS nanocomposite functionalized bridge-like membrane type nanomechanical sensing device for ultrasensitive blood lead detection
Yen YK, Yang CM, Kao CT, Yen TH, Shanmugam R, Chen YL and Lin HE
Lead (Pb) ion detection poses a critical problem, particularly in environmental monitoring, industrial operations, and public health, especially for young children and expecting women. Determining lead levels in blood early on is essential to minimizing the long-term consequences of lead exposure. Several sophisticated detection instruments, such as mass spectrometers which perform with high sensitivity, specificity and accuracy, but require a lab-based setting, multi-step sample preparation, expensive payment and professional operation. It is evident that a highly sensitive, portable, low-cost, quick sample-to-result, blood lead detection device that can be tested at the point-of-care is necessary. Consequently, we developed a unique ZnO/PEDOT:PSS nanocomposite layer integrated with a CMOS MEMS-based bridge-like membrane-type (BM) nanomechanical sensor for detecting lead levels in blood. PEDOT:PSS was combined with ZnO nanorods to increase lead ion binding. The sensor responds seven times better to lead ions using nanorods in the detecting layer. A linear resistance change rate response was found from 0.005 to 10 ppm, with the limit of detection (LOD) of 0.12 ppb. Similarly, our BM nanomechanical sensor can correctly assess Pb in human serum with recovery rates of 86.25-150 %. Measurements of human blood samples from patients with varying lead ion concentrations validated by the standard AAS show a good linear connection with the BM nanomechanical sensors' concentration, with a regression coefficient of 0.92. This describes the first micromachined nanoachanical sensing system for detection of Pb in only 5 μL of human serum sample. The device achieves a time-to-result of less than 10 min. The system is designed to be very sensitive and offers affordable, disposable sensing chips together with a portable signal acquisition platform.
Radical-directed dissociation mass spectrometry for differentiation and relative quantitation of isomeric ether-linked phosphatidylcholines
Zhang X, Chen Q, Wu L, Zhang W and Zhao X
Ether-linked phosphatidylcholines (PCs) include both plasmanyl and plasmenyl PCs, which contain an ether or a vinyl ether bond at the sn-1 linkage position, respectively. Profiling and quantifying ether PCs with accurate structural information is challenging because of the common presence of isomeric and isobaric species in a lipidome.
Triple acquisition mass spectrometry (TRAM) combining targeted and non-targeted metabolomics in a single run
Panzenboeck L, Schoeny H, Stelzer B, Foels E, Glas M, Pühringer M, Hirschmann D, Loetsch D, Dorfer C, Rampler E and Koellensperger G
We introduce TRAM, a triple acquisition strategy on a high-speed quadrupole time-of-flight mass spectrometer for merging non-targeted and targeted metabolomics into one run. TRAM stands for "quasi-simultaneous" acquisition of (1) a full scan MS1, (2) top 30 data-dependent MS2 (DDA), and (3) targeted scheduled MS2 for multiple reaction monitoring (MRM) within measurement cycles of ∼1 s. TRAM combines the selectivity and sensitivity of state-of-the-art targeted MRM-based methods with the full scope of non-targeted analysis enabled by high-resolution mass spectrometry.
Multimodal chemical speciation techniques based on simultaneous high resolution molecular/atomic mass spectrometry applied to online target/non-target analysis: A tutorial review
Kato LS, Cerqueira da Silva VH, Campaci de Andrade D, Cruz G, Pedrobom JH, Raab A, Feldmann J and Arruda MAZ
If identifying target species is challenging regarding chemical speciation, non-target species present even more significant difficulties. Thus, to improve the performance of the methods, multimodal online coupling involving atomic and molecular mass spectrometry (LC-ICP-MS-ESI-HRMS) is an advance in this direction. Then, this kind of coupling is highlighted in this Tutorial Review, as well as some references emphasizing its potentialities and possible limitations. Some crucial definitions of speciomics, chemical speciation, and others are also included.