Detection of multiple tumor-associated DNA methylation variations can shed light on the pathogenesis and physiological characteristics underlying disease development. Herein, we constructed a target-stimulated gold nanoparticles (AuNPs)-assembly homogeneous sensing platform for multiple DNA methylation assays via singleparticle inductively coupled plasma mass spectrometry (SP-ICP-MS). The introduction of target methylated DNA could initiate the DNA glycosylase-assisted specific digestion of the Linker probe, thus leading to a reduction in the agglomeration of AuNPs. The AuNP aggregates with varying size distributions can be well discriminated by the intensity and frequency of the Au pulse signal utilizing SP-ICP-MS, thereby enabling dual-mode detection of methylated DNA with good accuracy. Through the modular design of Linker probes, this homogeneous sensing system is feasible for multiplexed DNA methylation analysis, showing good universality. Taking methylated MLH1 and methylated MGMT as representatives, the limit of quantification under the two quantification modes are 25.0 pmol L- 1 and 10.0 pmol L- 1 for methylated MLH1 and methylated MGMT, respectively. The proposed method was successfully applied to direct analysis of methylated MLH1 and methylated MGMT in 34 % human serum samples, demonstrating the robust resistance of the proposed method to biological matrices and its suitability for real biological sample analysis. The programmability and expandability of the homogeneous SPICP-MS strategy render it a promising candidate for disease-relevant biomolecule diagnostics and pathogenic mechanism research.

Amadori and Heyns compounds are key Maillard reaction intermediates, resulting from the reaction of a certain amino acid with glucose (Glu) or fructose (Fru), respectively. They play a dual role in augmenting cigarette aroma and attenuating sensory irritation, and their quantification in tobacco is vital for tobacco quality evaluation and Maillard reaction mechanism study. Currently, simultaneous quantification of Amadori and Heyns compounds derived from the same amino acid, which present as isomers, is encumbered by poor chromatographic separation, and reliance on unavailable specific fragment ions. Herein, a method based on high performance liquid chromatography combined with tandem mass spectrometry (HPLC-MS/MS) detection was developed for the simultaneous quantification of Amadori and Heyns compounds derived from the same three amino acids (alanine, proline, phenylalanine, abbreviated as Ala, Pro, and Phe, respectively) with an ion ratio strategy. Under the optimized conditions, the limits of detection ranging from 2.22 to 6.94 ng/mL were obtained for six target analytes (Fru-Phe/Glu-Phe, Fru-Pro/Glu-Pro, Fru-Ala/Glu-Ala). When the method was applied to tobacco leaf powder extracts, target Amadori and Heyns compounds were found in the range of 0.65-56.4 μg/g, with Heyns compounds consistently less abundant than Amadori counterparts. In the recovery test, target analytes showed recoveries of 76.8-111%. Compared with reported methods, the proposed method features universal applicability without requiring characteristic fragment ions or chromatographic separation. It provides a reliable tool for analyzing hard-to-separate sugar-derived Maillard intermediates in tobacco.

MNAzyme system has shown considerable potential in bioanalysis due to its high catalytic cleavage activity similar to natural nucleases. However, insufficient amplification efficiency remains a key challenge hindering their application. Herein, we developed an exonuclease III (Exo III) assisted recycling amplification (ERA) mediated MNAzymes cascade system (ERA-MNAzymes), and combined it with lanthanide (Tm) labelling inductively coupled plasma mass spectrometry (ICP-MS) for sensitive quantification of microRNA-21 (miR-21). Specifically, in the presence of target miR-21, the hairpin probe (HP) will efficiently recognize the target, forming a stable miR-21/HP duplex with a blunt 3’ -terminus. The miR-21/HP duplex will be cleaved by ERA, releasing large amounts of HP fragments (T1), and T1 will trigger the assembly of MNAzymes to cleave Substrate-Tm, generating abundant Tm-labeled fragments (T2) which can be captured by magnetic capture probes. After heat elution, the Tm-labeled fragments in the supernatant were subjected to ICP-MS for monitoring of 169Tm in the eluant, and the amount of miR-21 can be indirectly obtained. Benefiting from the synergistic signal amplification of ERA mediated MNAzymes, a desirable detection limit of 1.7 fmol L-1 was achieved, with a quantification range of 0.005 - 500 pmol L-1. The developed ERA-MNAzymes-ICP-MS analytical platform has been applied to miR-21 detection in clinical samples, demonstrating its favorable performance in complex biological matrices and promising potential for clinical biomarker detection.

Background A highly sensitive method for the quantification of methylated DNA was developed by integrating gold nanoparticles (AuNPs) labeling with inductively coupled plasma mass spectrometry (ICP-MS), coupled with the cascade amplification of exponential isothermal amplification (EXPAR) and deoxyribozyme (DNAzyme). In this design, the target methylated DNA binds to a specific single-stranded DNA (ssDNA), forming a complex that is recognized and cleaved by the modification-dependent endonuclease FspEI. This cleavage releases a distinct X sequence, which then serves as a primer to initiate the EXPAR process. The amplified X sequences function as Deoxyribozyme (DNAzyme), cleaving substrate strands on magnetic beads (MB-DNA-AuNPs probe) and releasing AuNPs for subsequent ICP-MS detection. Results The concentration of the target methylated DNA is quantitatively determined by measuring the released AuNPs via ICP-MS, while unmethylated DNA fails to trigger the cleavage and amplification cascade, ensuring high specificity. The proposed method achieved an exceptionally low limit of detection of 5.2 fmol L-1 for methylated DNA, which is approximately four orders of magnitude lower than that obtained with conventional elemental labeling ICP-MS methods. Furthermore, this method is capable of detecting target methylated DNA with different lengths and distinguishing a methylation level as low as 0.1% in mixed samples. Significance The practical applicability of this method was validated through the analysis of methylated DNA in real serum samples, with recoveries ranging from 89.6% to 96.5% in spiking experiments. These results indicate its strong potential for the sensitive and reliable determination of methylated DNA in complex biological samples, offering a powerful tool for epigenetic research and clinical diagnostics.

BACKGROUND:Three-dimensional printing (3DP) has shown great potential in the preparation of monolithic column microextraction chips, but insufficient functional groups and low specific surface area limit its application in the field of adsorption/extraction. Although various surface functionalization strategies have been developed to overcome these drawbacks, challenges such as tedious pretreatment, pore blocking, and the need for high-concentration doping still remained. In-situ growth of covalent organic frameworks (COFs) offers an ideal solution but is limited by multi-step modification process and the availability of native functional groups. Herein, a facile and universal strategy based on catalyst pre-doping was proposed for in-situ growth of COFs on 3DP monolithic columns. RESULTS:By incorporating a trace amount (1%) of scandium trifluoromethanesulfonate (catalyst) into commercial photocurable resins, a uniform COFs layer was successfully formed on 3DP monoliths through a single post-printing reaction, without compromising the printing performance or structural integrity of the monoliths. Compared with unmodified 3DP monoliths, the COFs-functionalized columns exhibited significantly enhanced adsorption efficiency (53-79% vs 3-55%) toward naphthalene and its metabolites, along with excellent reusability over 100 cycles. Furthermore, a 3DP integrated microfluidic chip, integrating on-chip cell lysis, COF-based monolithic microextraction, and PEEK interfacing, was developed and coupled with high-performance liquid chromatography-fluorescence detector (HPLC-FLD) for the online analysis of naphthalene and its metabolites in BEAS-2B cells. The detection limit ranged from 0.04 to 3.95 μg L-1. In cells exposed to 50 μmol L-1 of naphthalene, 2-OHNAP was detected with the concentration of 0.36 ± 0.03 μg L-1. SIGNIFICANCE:A facile and universal approach for the in-situ growth of COFs on 3DP monoliths was proposed, effectively circumventing the drawbacks of traditional methods, such as high-concentration nanomaterial doping and tedious surface pre-functionalization. Subsequently, a novel method based on COFs-functionalized 3DP integrated chips coupled with HPLC was established for the online analysis of naphthalene and its metabolites in biological samples, featuring rapid prototyping, simple operation, and low cost.

Nanoplastics (NPs) in aquatic environments raise concerns as carriers that alter the bioavailability of co-occurring pollutants, such as cadmium (Cd), affecting combined toxicity. Precision toxicology now demands single-cell assessments to provide novel insights into pollutant interactions. In this study, we utilized a 3D-printed droplet microfluidic platform integrated with time-resolved analysis (TRA)─inductively coupled plasma mass spectrometry (ICP-MS)─to investigate the uptake behavior of single algal cells exposed to Cd and Eu-containing polystyrene (PS) NPs. 3D printing enables rapid prototyping and design flexibility for optimized microfluidic chips, while the monolithic structure eliminates assembly errors, reduces dead volume, and supports large-scale production. The droplet platform offers high-throughput single-cell encapsulation; coupled with TRA-ICP-MS, it minimizes cross-contamination and enhances sensitivity for multielement single-cell analysis. Single-cell analysis revealed that coexposure increased both the proportion of Eu/Cd-containing cells and the uptaken Eu/Cd content. The adsorption of Cd2+ imparted a more positive surface charge to PS NPs. This promoted heterogeneous aggregation between algal cells and PS NPs, thereby enhancing the bioavailability of PS/Cd2+ to the algae. Complementing these single-cell measurements, bulk-cell assays were conducted to evaluate the toxicological impacts of coexposure to Cd and PS NPs on microalgae. The results demonstrate that coexposure to PS NPs and Cd2+ resulted in synergistic effects, including enhanced growth inhibition, photosynthetic impairment, membrane damage, and increased secretion of extracellular polymers. These findings highlight the increased ecological risks posed to aquatic organisms by the coexposure to PS NPs and Cd2+, emphasizing the need for comprehensive assessments of nanoplastic-pollutant interactions in aquatic ecosystems.

Multidimensional information (e.g., composition, location, size, and particle concentration) of nanoparticles (NPs) in plants is critical for elucidating their uptake, translocation, and transformation. However, accurate acquisition of this information in complex plant samples remains a great challenge. Laser ablation-single particle inductively coupled plasma-mass spectrometry (LA-spICP-MS) holds promise for in situ NPs analysis, but its reliability is hindered by determination of NPs transport efficiency (η) and discriminating NPs signals from ionic/aggregation-induced varying backgrounds. To address this challenge, we proposed a new LA-spICP-MS strategy with dual-calibration and dynamic baseline correction to realize rapid multidimensional analysis of AuNPs in real plants. First, a dual-calibration approach using standards containing AuNPs/AuCl4- was developed. It enables simultaneous determination of η and concentration response factor of Au, thereby achieving quantification of the size and particle number of AuNPs. Second, a dynamic baseline-corrected data processing workflow was established. Specifically, a baseline composed of continuous minimum points was constructed, and AuNPs signals were further discriminated using the peak width and maximum-to-minimum intensity ratio. Under optimal conditions, AuNPs larger than 20 nm can be discriminated even with the presence of AuCl4- at concentrations below 20 μg g-1. The developed LA-spICP-MS method was applied to analysis of the uptake of AuNPs and in vivo synthesis of AuNPs in Arabidopsis thaliana. The obtained results provide direct evidence for the transport pathways of exogenous AuNPs and in vivo synthesis of AuNPs. The integrated approach provides a comprehensive solution for multidimensional NPs analysis in biological tissues, facilitating in-depth understanding of NPs behavior in plants.

Accurate analysis of circulating tumor cell (CTC) heterogeneity at the single-cell level, in addition to circulating tumor cell (CTC) enumeration, holds great promise for advancing our understanding of cancer progression and therapeutic response. Magnetic-activated cell sorting integrated with microfluidics has emerged as a powerful tool for CTC isolation and phenotyping. However, this method is still plagued by inherent trade-offs among sample throughput, magnetic separation resolution, and recovery of CTC subpopulations for downstream analysis. To address these limitations, we report a DLD@MACS chip engineered to generate a magnetic field gradient within a deterministic lateral displacement (DLD) channel, which facilitates the simultaneous size-based enrichment of CTCs and magnetic separation of their epithelial cell adhesion molecule (EpCAM) expression-related phenotypes into distinct streams, including the separation and recovery of EpCAM-negative CTCs. The DLD@MACS chip enabled significantly higher sample throughput (200 μL/min) compared to reported MACS-based phenotyping methods. Furthermore, a synergistic effect between DLD and the magnetic field gradient yields an enhanced separation resolution even at low magnetization. Through single-cell inductively coupled plasma mass spectrometry (SC-ICP-MS) detection, this method was successfully applied to enumeration and phenotyping of CTCs in the blood samples from more than 30 breast cancer patients. The detected CTC number and relative EpCAM expression were correlated to the breast cancer stage and clinical treatment, demonstrating the promising clinical applicability of this method.

BACKGROUND:Single-cell analysis based on inductively coupled plasma mass spectrometry (ICP-MS) has made considerable advancement. Herein, we utilized photocuring 3D printing technique to construct an integrated microfluidic chip that contains concentration gradient generation, cell culture array and trapezoidal spiral focusing units, and developed a new method of the integrated microfluidic chip on-line combined with single-cell (SC)-ICP-MS for determination of silver (Ag) in single cells. RESULTS:By using 3D printing technique, it is able to fabricate microfluidic chip of intricate structures with straightforward, rapid and cost-effective nature. And the established approach enables high-throughput for single-cell analysis (63375 cells per min) while minimizing cell loss with high cell recovery (ca. 94%). Taking MCF-7 cells as representative cells, the proposed 3D printing integrated microfluidic chip-SC-ICP-MS system was applied for determination of Ag in single MCF-7 cells exposed to Ag+ or silver nanoparticles (AgNPs). The results showed that at single-cell levels, the cells incubated with AgNPs exhibited more significant differences between cells compared to the cells incubated with Ag+. SIGNIFICANCE:This work employs 3D printing technology, offering advantages in easier integration of the chip components. By integrating cell culture directly on-chip and removing the requirement for additional off chip cleaning, this work establishes a platform characterized by high cell recovery and throughput, making it a valuable tool for single-cell analysis.

To achieve rapid and accurate screening of volatile brominated/iodinated disinfection byproducts (DBPs) in drinking water, a non-target analytical method was proposed using gas chromatography-mass spectrometry (GC-MS) with selected ion monitoring (SIM)-assisted full-scan acquisition. A high-throughput liquid-liquid extraction (LLE) procedure was developed using an air‐driven mixing device, enabling parallel processing of four samples, along with a simplified water removal step. Compared with conventional manual shaking, the optimized LLE achieved higher extraction efficiency in just 1 min versus 5 min, and triple small-volume extractions significantly improved repeatability. The method was validated using 17 halogenated DBPs, yielding detection limits of 0.01-0.54 μg/L, recoveries of 82.9-135.9%, and relative standard deviations ≤15.4%. when applied to eight drinking water treatment plants, 29 DBPs were identified, including 10 novel brominated/iodinated alcohols. Notably, 1‐bromo‐2‐methyl‐2‐propanol and 2‐methyl‐3‐bromo‐2‐butanol – previously detected only in laboratory ozonation experiments – were reported for the first time in real chlorinated tap water. This finding indicates that some DBPs previously considered exclusive to ozonation may also form during chlorination in practical drinking water treatment.

BCR-ABL fusion genes are gold-standard biomarkers for chronic myeloid leukemia (CML), but conventional detection methods suffer from cumbersome procedures, RNA preamplification needs, and an inability to quantify multiple subtypes simultaneously. Herein, we developed a one-pot enzyme-free cascade amplification system coupling toehold-mediated strand displacement reaction (TMSD) and hybridization chain reaction (HCR), combined with lanthanide-tagged inductively coupled plasma-mass spectrometry (ICP-MS), for the simultaneous quantification of four BCR-ABL subtypes (p190 e1a2, p210 e13a2, p210 e14a2, and p230 e19a2). The system uses tetrahedral DNAs (TDN1/TDN2) to optimize the probe orientation and amplification efficiency. Detection limits were 0.59, 0.82, 0.33, and 0.16 fM for the four subtypes, respectively. Validated in 70 clinical samples (40 CML patients, 30 healthy volunteers), it distinguished subtypes in bone marrow/peripheral blood, correlated well with qRT-PCR, and evaluated tyrosine kinase inhibitor (TKI) efficacy. This method avoids RNA reverse transcription and multitube reactions, providing a robust tool for CML diagnosis and targeted therapy monitoring.

The isolation and detection of circulating tumor cells (CTCs) play a significant role in early cancer diagnosis and prognosis. Negative magnetophoresis sorting is a label-free method, providing easy access to enrich intact and viable CTCs, but it struggles to meet the demands of high-throughput separation and direct downstream analysis. In this work, a facile cascaded negative magnetophoresis microfluidic chip was fabricated and online coupled to inductively coupled plasma mass spectrometry (ICP-MS) for the rapid separation and detection of rare CTCs in blood samples. The chip consisted of two parts: a negative magnetophoresis sorting zone and a negative magnetophoresis phase-transfer zone. In the sorting zone, WBCs labeled with anti-CD45-magnetic beads (MBs) dispersed in biocompatible ferrofluid were removed by magnetic attractive force, while CTCs labeled with anti-EpCAM-Eu migrated into the phase-transfer zone by magnetic repulsive force; in the phase-transfer zone, due to the stable laminar flow formed by the magnetic fluid and PBS buffer, CTCs migrated into the PBS under both the magnetic repulsive force and inertial lift force and online introduced into ICP-MS for detection. This device can achieve CTC enrichment at a high throughput of 100 μL min-1 and has the capability for direct downstream analysis and recultivation (cell viability of 99.27%). The method was applied for the detection of CTCs in real clinical blood samples from 10 patients diagnosed with various cancers, and the detection rate was 100%, providing a simple and efficient approach for clinical detection of rare CTCs.

3D printing is an additive manufacturing technology based on digital model files. 3D printing has become a popular manufacturing tool in various fields. Stereolithography offers a series of advantages compared to its counterparts, such as smooth prints, appropriate resolution in all the axes, acceptable organic solvent compatibility and sufficient tightness to the flowing of solutions/solvents at moderate/high pressure. Thus, this work used stereolithography and clear resin (polymethyl methacrylate resin and epoxy resin) to prepare stir bars' coatings, which reduced the size of the fabricated stir bar (1 mm) and no swelling property in organic solvents. In this work, three types of structures were designed as the coatings of stir bars, which were solid, discal, and lattice coatings with equal mass (0.13 g). Because of the largest surface area, lattice coatings were chosen to make clear resin stir bars. The clear resin stir bars were used for stir bar sorptive extraction and combined with high performance liquid chromatography to develop a new method, which was successfully applied to detect four chlorophenols in environmental water samples. Compared with the previous work using melt deposition modeling 3D printing, this work could print hollow structures with higher precision. The stir bars could have higher rotational speed (700 rpm vs 350 rpm), smaller desorption volume (500 mu L vs 2 mL), and shorter extraction time (60 min vs 90 min). The stir bars also had excellent mechanical performance and long lifetimes of up to 160 times. LODs of this method were between 0.30 mu g/L (2-CP) and 0.97 mu g/L (2,4,6-TCP) (S/N = 3), which were below the concentration limits of surface water samples. Relative standard deviations of the stir bars were 1.4-3.9 % (n = 7, c = 10 mu g/L).

Controlling the position, size, and shape of pores is a limitation of traditional monolithic preparation methods. The application of 3D printing technology offers high customizability, allowing the precise printing of pore positions, sizes, and shapes according to the designer's 3D model. Herein, by using Projection Microstereolithography (P mu SL), we prepared a 3D-printed monolithic array with post-modification of thiol-functionalized metal-organic framework (MOF), and combined it with inductively coupled plasma mass spectrometry (ICP-MS) for the online analysis of trace Cd and Pb in human urine. To achieve array monolithic microextraction, six 3D-printed monolithic columns were modified with thiol-functionalized MOF-808 (MOF-808-SH), and were then assembled in the 3D printed extraction device incorporating gas valve and scaffold. The MOF-808-SH modified 3D-printed monolithic column exhibits excellent extraction performance to Cd2+ and Pb2+ due to rich active adsorption sites and hierarchical porous structure, and has long life span (>100 reused times). Under the optimized conditions, the limits of detection (LODs) are 3.5 and 17.6 ng L-1 for Cd2+ and Pb2+, respectively, with the relative standard deviations of 4.9 % and 8.2 % (0.1 mu g L-1, n = 7), and the sample throughput is 11 h(-1). To validate the accuracy of the method, the method was used to determine Cd and Pb in Certified Reference Materials of freeze-dried human urine, the determined results agree well with the certified values. This method was also successfully applied to the determination of trace Cd and Pb in real human urine samples. The developed method offers low LODs, robust anti-interference capability, high sample throughput, long reuse cycles, and automation analysis, showing great potential for the analysis of trace heavy metals in biological samples.

Single particle (SP)-ICP-MS with elemental labeling is a new technique for quantification analysis of biospecies with good sensitivity, high specificity and strong anti-matrix interference ability, but barely applied for detection of toxins. Herein, we developed a homogeneous SP-ICP-MS assay for detection of aflatoxin B1 (AFB1) based on aptamer recognition, multicomponent nucleic acid enzyme (MNAzyme) amplification, and AuNP elemental labeling probes. In the absence of AFB1, the Linker DNA is complementary to the two AuNP probes, which will form large assembly AuNP aggregates. In the presence of AFB1, it specifically bonds to the aptamer to release the primer from aptamer-primer hybridized chains, which activates the MNAzyme system to cleave the Linker, causing the formed AuNP aggregates reduced. The AuNP aggregates in the solution are subjected to SP-ICP-MS detection by monitoring the Au pulses signals, and sensitive detection of AFB1 can be achieved via correlating the signal intensity of AuNP aggregates with the concentration of AFB1. Under the optimal experimental conditions, the lower limit of quantitation for AFB1 was 0.5 fg/mL, the quantitation range was 0.5-1000 fg/mL, and the relative standard deviation was 3.2 % (c = 200 fg/mL, n = 7). The accuracy of the method was verified by the determination of AFB1 in quality control corn meal sample, revealing the method can be used to detect AFB1 in complex food matrix. The method was successfully applied to the detection of AFB1 in rice, wheat and peanut samples. The developed method has the advantages of high sensitivity, good specificity, and ease of operation, providing a new approach for toxin analysis in various food.

Three-dimensional printing (3DP) technology was applied to fabricate an all-in-one sample introduction system for inductively coupled plasma mass spectrometry (ICP-MS) analysis of ultratrace rare-earth elements (REEs) in cells. The developed 3DP all-in-one sample introduction system comprised a microfluidic chip integrating cell lysis and monolithic microextraction array, a microvalve control unit, and a microflow total consumption high-efficiency nebulizer (MTHEN). It made full use of the advantages of 3DP in preparing user-customized three-dimensional structures. On the one hand, an integrated chip consisting of a three-dimensional mixing zone and array monolithic columns with a skeleton structure of UiO-66 was printed directly, which are beneficial for mixing the cells with lysis buffer and extraction of target elements from the cell lysate, respectively, as well as improving the mass transfer. On the other hand, the 3DP-MTHEN with a customized interface was directly connected to an ICP torch, providing a high sample transport efficiency (81.1%) under a low flow rate of 6 μL min-1. The sensitivity of ICP-MS by using a 3DP-MTHEN for representative elements was 4.7-6.0 times higher than that obtained by using a commercial microflow Burgener SC175 nebulizer (detection limits of 0.7-13.3 vs 0.7-52.6 ng L-1). Besides, the 3DP-MTHEN exhibited a lower cost ($13 vs 1550). The proposed system has been applied to the determination of ultratrace REEs in MCF-7 cells. It exhibited simple operation, low cell consumption (500 cells), good precision (2.2-11.9%), low detection limit (1.3-8.6 ng L-1), and quantitative recovery (71.9%-119%). It merits application potential for ultratrace elemental analysis in samples with very limited volume, especially cells.

Cadmium threatens eco-environmental security and human health, but the interaction between cadmium and microalgae cells remains unknown. This research examined the molecular detoxification mechanism of Synechocystis sp. to cadmium. The results indicated that cadmium stress significantly inhibited chlorophyll a content and maximum photochemical quantum yield (Fv/Fm), with EC50 of 0.50 mg L-1. The differentially expressed genes/proteins (DEGs/DEPs) were significantly enriched in pathways of two-component system, translation, nucleotide metabolism, ribosome, photosynthesis and chlorophyll synthesis. 1073 DEGs and 338 DEPs were identified, and 84 DEGs/DEPs with consistent expression trends were obtained. Foldchange of Sll1725 ranked fourth in DEGs/DEPs but its function was unexplored. Phylogenetic analysis and 3D structure identified Sll1725 as an ABC transporter and molecular simulation determined its cadmium-efflux function. Under 0.50 mg L-1 cadmium stress, Δsll1725 had lower growth and Fv/Fm values than the wild-type. Meanwhile, the intracellular cadmium in Δsll1725 was higher, indicating that Sll1725 mitigated cadmium toxicity by efflux. The duckweed with overexpressed sll1725 exhibited cadmium tolerance. It could be deduced that Sll1725, belonged to ABC transporters, which played an important detoxification mechanism. These mutants might possess the potential for bioremediation. This study provides a basis for applying algal genetic resources in cadmium pollution treatment.

Circulating tumor cells (CTCs) have emerged as critical biomarkers for early cancer diagnosis. Elemental labeling inductively coupled plasma mass spectrometry (ICP-MS) has high sensitivity and specificity for cell counting. Microfluidic sorting chips combined with ICP-MS, enabling online separation/enrichment and detection of CTCs, could be a promising analytical technique for advancing biomedical research and clinical diagnostics. To this end, a dual asymmetric contraction-expansion array (ACEA-ACEA) integrated chip-ICP-MS online detection platform was developed for the rapid isolation and detection of CTCs in blood samples. The designed integrated chip, consisting of two ACEA channels with different structural parameters, achieved two-stage removal of white blood cells (WBCs) by synergistic inertial lift and Dean forces, thereby greatly improving the CTC purity. The Eu-labeled CTCs focused in a single stream were then directly introduced into ICP-MS from the target outlet for online detection. The peak frequency of Eu labeled on the cell surface could reflect the number of CTCs. The designed integrated ACEA-ACEA chip was used for cell sorting, and a good sorting performance was obtained with a throughput of 300 μL min-1, CTC recovery of 94.18%, and WBC removal efficiency of 99.46%. The developed method was applied for CTC counting in blood samples collected from 10 healthy individuals and 42 cancer patients. No CTCs were identified in healthy control samples, while the number of CTCs detected in cancer patients' samples ranged from 10 to 176 cells mL-1. Notably, the number of detected CTCs was positively correlated with the patients' TNM staging [stands for Tumour (T), Node (N) and Metastasis (M)] results. The fabricated ACEA-ACEA chip was sheath-flow-free and external-field-free, and the developed method could be used for the detection of CTCs in blood samples with high throughput, high sensitivity, and high accuracy, exhibiting great application value and potential in medical diagnosis.

Three-dimensional printing (3DP) technology enables the flexible fabrication of integrated monolithic microextraction chips for high-throughput sample pretreatment. Meanwhile, the extraction performance of 3DP-based channels is largely limited by printer resolution and the commercially available printing materials. In this work, a 3DP array monolithic microextraction chip (AMC) was fabricated by integrating 26-array helical monolithic microextraction channels for sample pretreatment and 52-array gas valves for fluid control. 3DP with a liquid crystal display, switching between flexible and rigid resins, was employed to fabricate fluid-control valves and helical microchannels, respectively. Hierarchical porous monolithic column in microchannels was obtained by in-situ polymerization of a high internal phase Pickering emulsion, with carbonyl-containing covalent organic frameworks (COFs) employed for the first time as both emulsifier and stabilizer. The amphiphilic COFs with balanced hydrophilic carbonyl groups and hydrophobic benzene rings was selected to facilitate the emulsion template formation for the monolith's porous structure while providing effective functional sites for adsorption. The helical shape and internal hierarchical porous structure of the monolithic column both help to improve mass transfer during adsorption and desorption. Based on the above facts, a method by online coupling 3DP-AMC with inductively coupled plasma-mass spectrometry (ICP-MS) detection was developed for the analysis of rare-earth elements (REEs) in environmental samples. The developed method has a high sample throughput (30 h-1), a wide linear range (0.001-50 μg L-1), low limits of detection (0.3-0.8 ng L-1), and good precisions (relative standard deviations of 2.7%-9.4%). Its application potential was demonstrated by analyzing trace/ultratrace REEs in different samples with complicated matrix, including atmospheric particulate matter, environmental water, soil, human urine, and human hair.