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1.
Chemosphere ; 356: 141902, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38582158

RESUMO

Sediment siltation has been regarded as the serious challenge in sewer system, which dominantly root in the gelatinous extracellular polymeric substance (EPS) structure and cohesive ability. Considering the crucial roles of divalent cation bridging and macromolecular biopolymer winding in sediment EPS formation and adhesive behavior, an innovative combination strategy of sodium pyrophosphate (SP)-mediated divalent cation chelation and alkaline biopolymer hydrolysis was developed to degenerate sediment adhesion. At the SP dosage of 0.25 g/g TS and the alkaline pH 12, the SP + pH 12 treatment triggered structural transformation of aromatic proteins (α-helix to ß-turn) and functional group shifts of macromolecular biopolymers. In this case, the deconstruction and outward dissolution of gelatinous biopolymers were achievable, including proteins (tyrosine-like proteins, tryptophan-like proteins), humic acids, fulvic acids, polysaccharides and various soluble microbial products. These were identified as the major driving forces for sediment EPS matrix disintegration and bio-aggregation deflocculation. The extraction EPS content was obviously increased by 18.88 mg COD/g TS. The sediment adhesion was sensitive to EPS matrix damage and gelatinous biopolymer deconstruction, leading to considerable average adhesion degeneration to 0.98 nN with reduction rate of 78.32%. As such, the sediments could be disrupted into dispersive fragments with increased surface electronegativity and electric repulsion (up to -45.6 mV), thereby the sediment resistance to hydraulic erosion was impaired, providing feasibility for in-situ sediment floating and removal by gravity sewage flow in sewer.


Assuntos
Esgotos , Biopolímeros/química , Hidrólise , Esgotos/química , Quelantes/química , Eliminação de Resíduos Líquidos/métodos , Cátions/química , Concentração de Íons de Hidrogênio , Matriz Extracelular de Substâncias Poliméricas/química
2.
Dalton Trans ; 53(2): 612-618, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38063675

RESUMO

The field of molecular catalysts places a strong emphasis on the connection between the ligand structure and its catalytic performance. Herein, we changed the type of coordinated nitrogen atom in pentadentate amine-pyridine ligands to explore the impact of its hybridization form on the water oxidation performance of copper complexes. In the electrochemical tests, the copper complex bearing dipyridine-triamine displayed an apparently higher rate constant of 4.97 s-1, while the copper complex with tripyridine-diamine demonstrated overpotential reduction by 56 mV and better long-term electrolytic stability.

3.
Chemosphere ; 341: 140102, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37683954

RESUMO

In decades, anaerobic fermentation with short-chain fatty acids (SCFAs) recovery from excess sludge have attained rising attention. However, rigid particulate organic matter (POMs) structure with slow hydrolysis limited anaerobic fermentation performance of excess sludge. Remarkable sludge hydrolysis performance was supposed to be achievable by the synchronous EPS repture and microbial cell lysis. This study clarified the improvement of overall anaerobic fermentation performance by combination treatment of lysozyme (Lyso) catalysis and metal regulation (MR). The Lyso + MR treatment triggered EPS rupture by protein structure deflocculation while catalyzing microbial cell lysis, which promoted massive extracellular and intracellular POMs hydrolysis. As a result, a significant amount of SCOD (5646.67 mg/L) was produced. Such endogenous organic matters hydrolysis led to considerable SCFAs accumulation (3651.14 mg COD/L) through 48-h anaerobic fermentation at 1.75 g/g SS cation-exchange resin and Lyso dosage of 10% (w/w), which was 5.945 times higher than that in the control. Additionally, it suggested that most of the recovered SCFAs remained in fermentative liquid after chemical conditioning and mechanical dewatering towards solid-liquid separation, which provided considerable economic benefit of 363.6-1059.1 CNY/ton SS.


Assuntos
Resinas de Troca de Cátion , Esgotos , Hidrólise , Esgotos/química , Muramidase , Fermentação , Ácidos Graxos Voláteis , Biopolímeros , Concentração de Íons de Hidrogênio , Anaerobiose
4.
Small ; 19(45): e2304889, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37438574

RESUMO

Heterogeneous oxides with multiple interfaces provide significant advantages in electrocatalytic activity and stability. However, controlling the local structure of these oxides is challenging. In this work, unique heterojunctions are demonstrated based on two oxide types, which are formed via pyrolysis of a ruthenocene metal-organic framework (Ru-MOF) at specific temperatures. The resulted Ru-MOF-400 exhibits excellent electrocatalytic activity, with an overpotential of 190 mV at a current density of 10 mA cm-2 in 0.1 m HClO4 , and a mass activity of 2557 A gRu -1 , three orders of magnitude higher than commercial RuO2 . The Ru─O─Co bond formed by the incorporation of Co into the rutile lattice of RuO2 inhibits the disolution of Ru. Operando electrochemical investigations and density functional theory results reveal that the Ru-MOF-400 undergo asymmetric dual-active site oxide path mechanism during the acidic oxygen evolution reaction process, which is predominantly mediated by the asymmetric Ru─Co dual active site present at the interfaces between Co3 O4 and CoRuOx .

5.
Angew Chem Int Ed Engl ; 62(28): e202302581, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37042048

RESUMO

Supramolecular copolymers have attracted much attention due to their potential functionalities. However, the co-assembly strategies to construct co-assemblies of small molecules with well-defined sequence structures are still limited, especially for more complex crystalline block co-assemblies. Herein, we target this challenge by designing IrIII complexes 1 and 2, which possess unique self-assembly pathways and are capable of forming crystalline assemblies in aqueous systems. Specifically, block and random co-assemblies of 1 and 2 can be synthesized by kinetic and thermodynamic control, respectively. Meanwhile, by adjusting the water content to orthogonalize the on-pathway and the off-pathway, an unprecedented pathway-switching approach is realized to synthesize block and random co-assemblies. By coupling the kinetic pathways, the present co-assembly strategies are expected to pave the way for the synthesis of crystalline co-assemblies of small molecules and the construction of organic heterostructures.

6.
Clin Appl Thromb Hemost ; 29: 10760296221151164, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36650933

RESUMO

AIM: To develop and validate a risk assessment model (RAM) of venous thromboembolism (VTE) in hospitalized Chinese patients. METHODS: We reviewed data from 300 patients with VTE and 300 non-VTE patients at Beijing Shijitan Hospital. The risk factors related to VTE were analyzed, and the VTE RAM (Shijitan (SJT) version) was developed according to the weight of each risk factor. A total of 407 patients with VTE and 533 non-VTE patients were enrolled for external validation. The sensitivity, specificity, Youden index, receiver operating curve (ROC), and area under the ROC curve (AUC) were used to evaluate the performance of VTE RAM (SJT version) compared with Caprini RAM and Padua RAM. RESULTS: The VTE RAM (SJT version) contained six risk factors (age >60 years, lower limb edema, chronic obstructive pulmonary disease (COPD), central venous catheterization (CVC), VTE history, and D dimer). In the external validation group, for medical patients, the AUC value of SJT RAM (0.82 ± 0.03) is significantly higher than Caprini RAM (0.76 ± 0.04; P < 0.05), SJT RAM has a higher sensitivity, specificity, and Youden index than Caprini RAM (P < 0.05), which means that the SJT RAM has a much better predictive value than Caprini RAM. While SJT RAM and Padua RAM have the similar predictive value for medical patients (P > 0.05). For surgical patients, the AUC value of SJT RAM (0.72 ± 0.04) is significantly higher than the value of Padua RAM (0.66 ± 0.04; P < 0.05), SJT RAM has a higher sensitivity, specificity, and Youden index than Padua RAM (P < 0.05), which shows that the VTE RAM has better predictive value than Padua RAM. While SJT RAM and Caprini RAM have the similar predictive value for surgical patients (P > 0.05). CONCLUSION: The SJT RAM derived from general hospitalized Chinese patients will be time-saving for physicians and has a better predictive ability for patients at risk of VTE.


Assuntos
Tromboembolia Venosa , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/etiologia , China
8.
Cell Mol Neurobiol ; 43(3): 1181-1196, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35661286

RESUMO

Lanthanum (La) is a natural rare-earth element that can damage the central nervous system and impair learning and memory. However, its neurotoxic mechanism remains unclear. In this study, adult female rats were divided into 4 groups and given distilled water solution containing 0%, 0.125%, 0.25%, and 0.5% LaCl3, respectively, and this was done from conception to the end of the location. Their offspring rats were used to establish animal models to investigate LaCl3 neurotoxicity. Primary neurons cultured in vitro were treated with LaCl3 and infected with LKB1 overexpression lentivirus. The results showed that LaCl3 exposure resulted in abnormal axons in the hippocampus and primary cultured neurons. LaCl3 reduced the expression of LKB1, p-LKB1, STRAD and MO25 proteins, and directly or indirectly affected the expression of LKB1, leading to decreased activity of LKB1-MARK2 and LKB1-STK25-GM130 pathways. This study indicated that LaCl3 exposure could interfere with the normal effects of LKB1 in the brain and downregulate LKB1-MARK2 and LKB1-STK25-GM130 signaling pathways, resulting in abnormal axon in offspring rats.


Assuntos
Axônios , Lantânio , Ratos , Feminino , Animais , Lantânio/toxicidade , Ratos Wistar , Transdução de Sinais , Proteínas Serina-Treonina Quinases
9.
Inorg Chem ; 61(40): 16197-16202, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36168991

RESUMO

We demonstrate a dialytic strategy for the synthesis of congeneric two-dimensional metal-organic framework (2D MOF) nanosheets with a dialysis membrane using 1,4-benzenedicarboxylic acid (BDC), 1,4-naphthalenedicarboxylic acid (NDC), and 9,10-anthracenedicarboxylic acid (ADC) as organic linkers and copper(II) as a metal precursor, respectively. Polyimide (PI) membranes containing these empty 2D MOF nanosheets exhibit distinct molecular sieve effects. Molecular dynamic simulation results reveal that the structures of MOF-polymer interfaces are designable by modifying the MOF interlayer distance and aperture size, which has significant influences on gas permeability and selectivity. As a result, Cu-NDC/PI with the moderate composite interface structure shows superior performance toward H2/CH4 and CO2/CH4 separations with a selectivity of 199 and 63 over Cu-BDC (121 and 53) and Cu-ADC (135 and 54), respectively.

10.
ChemSusChem ; 15(14): e202200704, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35567361

RESUMO

The synthesis of Co-doped Mn3 O4 nanocubes was achieved via galvanic replacement reactions for photo-reduction of CO2 . Co@Mn3 O4 nanocubes could efficiently photo-reduce CO2 to CO with a remarkable turnover number of 581.8 using [Ru(bpy)3 ]Cl2 ⋅ 6H2 O as photosensitizer and triethanolamine as sacrificial agent in acetonitrile and water. The galvanic replaced Co species are homogeneously distributed at the outer surface of Mn3 O4 , providing catalytic active sites during CO2 reduction reactions, which facilitate the separation and migration of photogenerated charge carriers, further benefiting the outstanding photocatalytic performance of CO2 reduction. Density functional theory calculations revealed that the decreasing of conduction band maximum in Co@Mn3 O4 was beneficial to the electron attachment from the excited sensitized molecule, which promoted photocatalytic reduction of CO2 .

11.
Biomed Pharmacother ; 149: 112890, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35367757

RESUMO

In eukaryotic cells, organelles could coordinate complex mechanisms of signaling transduction metabolism and gene expression through their functional interactions. The functional domain between ER and mitochondria, called mitochondria-associated membranes (MAM), is closely associated with various physiological functions including intracellular lipid transport, Ca2+ transfer, mitochondria function maintenance, and autophagosome formation. In addition, more evidence suggests that MAM modulate cellular functions in health and disease. Studies have also demonstrated the association of MAM with numerous diseases, including neurodegenerative diseases, cancer, viral infection, obesity, and diabetes. In fact, recent evidence revealed a close relationship of MAM with Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), amyotrophic lateral sclerosis (ALS), and other neurodegenerative diseases. In this view, elucidating the role of MAM in neurodegenerative diseases is particularly important. This review will focus the main tethering protein complexes of MAM and functions of MAM. Besides, the role of MAM in the regulation of neurodegenerative diseases and the potential molecular mechanisms is introduced to provide a new understanding of the pathogenesis of these diseases.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Doença de Alzheimer/metabolismo , Retículo Endoplasmático/metabolismo , Humanos , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Doenças Neurodegenerativas/patologia
12.
Sci Rep ; 12(1): 6819, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35474065

RESUMO

To overcome the limitation of the virtual extensometer method in measuring the crack opening displacement (COD) in the process of complex multi-crack propagation of rock, the measurement error of Digital Image Correlation (DIC) local deformation is theoretically analyzed. An improved virtual extensometer method for measuring the COD is proposed, which considers the temporal and spatial characteristics of crack development in the process of complex crack propagation. The accuracy of the proposed method is verified by the strain localization band numerical simulation test and indoor single crack simulation test. Furthermore, the method is applied to the two-dimensional similarity simulation test of simulating complex multi-fractures in rock stratum. The COD obtained by the traditional and improved methods is compared with the measured COD. The results show that in the case of multiple complex cracks, to obtain the COD accurately, the relative distance between the virtual extensometer measuring point and the crack should be greater than half of the sum of the width of the crack strain localization zone and the subset size. With the development of the crack, the relative distance between the virtual extensometer measuring point and the crack should increase with the increase of the width of the crack strain localization zone. The error of the COD measured by the traditional method increases with fracture development, and the maximum is 21.20%. The maximum relative error between the COD measured by the improved method and the measured crack opening is 3.61%. The research results improve the accuracy of the virtual extensometer in measuring the COD under complex multi-crack conditions.

13.
Food Chem Toxicol ; 161: 112831, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35090998

RESUMO

Lanthanum is one of REEs documented to have neurotoxicity that led to learning and memory ability impairments. However, the mechanisms underlying La-induced neurotoxicity remain largely unexplored. Autophagy is a self-balancing and self-renewal process that degrades damaged organelles and macromolecules through lysosomal pathway. Importantly, appropriate autophagy levels have protective effects against harmful stress, while excessive autophagy has been demonstrated to be implicated in neurological diseases. ER is close to mitochondria at specific sites with a reported distance of 10-30 nm. The functional domains between the two organelles, called MAM, have been associated with autophagosome synthesis. In this study, the pregnant Wistar rats were randomly divided into four groups and given distilled water solution containing 0%, 0.125%, 0.25%, and 0.5% LaCl3 for drinking during gestation and lactation. The pups were exposed to LaCl3 via the maternal placenta and three-week lactation. Experimental results showed that LaCl3 decreased spatial learning and memory ability of offspring rats, decreased tethering protein complexes expression of MAM, damaged MAM structure, up-regulated NOX4 expression which led to active ROS-AMPK-mTOR signaling pathway. Our findings suggest that decreased spatial learning and memory ability induced by LaCl3 may be related to the abnormally autophagy regulated by tethering protein complexes of MAM.


Assuntos
Autofagia/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Lantânio/toxicidade , Membranas Mitocondriais/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Feminino , Hipocampo/metabolismo , Lactação , Masculino , Mitocôndrias , Membranas Mitocondriais/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Distribuição Aleatória , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Aprendizagem Espacial/efeitos dos fármacos
14.
Angew Chem Int Ed Engl ; 60(23): 12770-12774, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33768623

RESUMO

We report the synthesis of two-dimensional metal-organic frameworks (MOFs) on nickel foam (NF) by assembling nickel chloride hexahydrate and 1,1'-ferrocenedicarboxylic acid (NiFc-MOF/NF). The NiFc-MOF/NF exhibits superior oxygen evolution reaction (OER) performance with an overpotential of 195 mV and 241 mV at 10 and 100 mA cm-2 , respectively under alkaline conditions. Electrochemical results demonstrate that the superb OER performance originates from the ferrocene units that serve as efficient electron transfer intermediates. Density functional theory calculations reveal that the ferrocene units within the MOF crystalline structure enhance the overall electron transfer capacity, thereby leading to a theoretical overpotential of 0.52 eV, which is lower than that (0.81 eV) of the state-of-the-art NiFe double hydroxides.

15.
Front Psychol ; 12: 750421, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35002848

RESUMO

This research aims to explore the reality of the soundscape preferences of Chinese urban residents in general public landscape in the post-pandemic era, and then to propose design recommendations to meet the practical needs of people's preferences for landscape-especially soundscapes-in the post-pandemic era. In this study, we utilized the subjective evaluation method to conduct an online questionnaire in 29 Chinese provinces which experienced severe pandemic caseloads and collected 860 valid responses. This study revealed people's preference for landscape and soundscape in the post-pandemic era. We further studied the correlation between landscape preference and soundscape preference, analyzed the influence of living conditions on soundscape preference, founded the effects of personal characteristics and living conditions on soundscape preference, and explored the strongest influence factors on soundscape preference through the establishment of automatic linear model. The results revealed a positive correlation between life happiness and soundscape preference, whereas wearing masks significantly reduced soundscape perception ratings and people who have been vaccinated are more tolerant of various noises. Moreover, based on these analysis results, the design recommendations on landscape (overall landscape, plant, and tour space), soundscape construction of caring for vulnerable groups (teenagers and children, elderly people, and disabled and unhealthy) has been discussed.

16.
Mol Immunol ; 130: 104-112, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33309306

RESUMO

Atopic dermatitis is a severe, chronic relapsing inflammatory disease of the skin with family clustering. It is characterized into acute phase, which is dominated by T helper 2-type immune responses, and chronic phase, which is dominated by T helper 1-type immune responses. Studies have shown that 3,3'-diindolylmethane not only has antitumor effects but also can relieve symptoms of inflammatory diseases by inhibiting the nuclear factor-κB signaling pathway and regulating T cell differentiation. To study the effect of 3,3'-diindolylmethane on atopic dermatitis and the underlying mechanism, a mouse model of acute atopic dermatitis was established using 2,4-dinitrofluorobenzene. After intraperitoneal injection of 3,3'-diindolylmethane, skin erythema and edema in mice were significantly alleviated. Furthermore, 3,3'-diindolylmethane reduced immune activation, probably by inhibiting the secretion of thymic stromal lymphopoietin by keratinocytes. 3,3'-Diindolylmethane also promoted the differentiation of regulatory T cells and inhibited the activation of T helper 2 and T helper 17 cells to reduce atopic dermatitis-related immune responses. However, it showed no significant effect on the differentiation of T helper 1 cells. These results indicate that 3,3'-diindolylmethane has a significant inhibitory effect on T helper 2 cells in the acute phase of atopic dermatitis. Our findings may provide not only more insights into the pathological mechanism of AD, but also a new candidate medicine for it.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Dermatite Atópica/tratamento farmacológico , Indóis/uso terapêutico , Linfócitos T/efeitos dos fármacos , Doença Aguda , Adulto , Animais , Diferenciação Celular/imunologia , Células Cultivadas , Dermatite Atópica/imunologia , Modelos Animais de Doenças , Feminino , Células HaCaT , Humanos , Indóis/farmacologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/fisiologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Pele/efeitos dos fármacos , Pele/imunologia , Linfócitos T/fisiologia
17.
ACS Appl Mater Interfaces ; 12(21): 24059-24065, 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32364366

RESUMO

Recent developments have been highlighted for UiO-type materials, a class of metal-organic frameworks (MOFs) with high stability, as catalysts for photocatalytic CO2 reduction. We design and synthesize two metal ion (Co2+, Re+)-doped UiO-67 as catalysts for the photocatalytic CO2 reduction reaction and demonstrate that Co-UiO-67 exhibits better photocatalytic activity relative to Re-UiO-67. The superior photocatalytic activity of Co-UiO-67 over Re-UiO-67 results from the improved charge transportability and higher CO2 adsorption capacity. Density functional theory (DFT) calculations reveal that the energy barrier of Co-UiO-67 (0.86 eV) for catalytic CO2 reduction to CO is lower than that of Re-UiO-67 (0.92 eV), thus leading to superior photocatalytic performance of Co-UiO-67 than that of Re-UiO-67.

18.
Chem Commun (Camb) ; 56(16): 2419-2422, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31994548

RESUMO

The rational manipulation of reaction intermediates is crucial for achieving high-performance heterogeneous catalysis. Herein, using in situ Fourier transform infrared-diffuse reflection (FTIR) analysis, we report that the methanol oxidation reaction (MOR) intermediates can be controlled by precisely tuning the location and content of Ru on the Pt-Ru alloy surface.

19.
ACS Appl Mater Interfaces ; 11(16): 14862-14870, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-30933467

RESUMO

An effective design for counter electrode (CE) catalytic materials with superior catalytic activity, excellent stability, low cost, and a facile fabrication process is urgently needed for industrialization of dye-sensitized solar cells (DSSCs). Herein, we report a facile in situ method to fabricate transparent CoS1.097 anchored on an N-doped carbon film electrode through sulfurization of a cobalt-metalloporphyrin metal-organic framework thin film on fluorine-doped tin oxide glass. The transparent film as counter electrode in bifacial DSSCs exhibited higher power conversion efficiency (9.11% and 6.64%), respectively, from front and rear irradiation than that of Pt (8.04% and 5.87%). The uniformly dispersed CoS1.097 nanoparticles on an N-doped carbon film provide a large catalytic active area and facilitate the electron transfer, which leads to the excellent catalytic ability of the CoS1.097@N-doped carbon film. In addition, the in situ preparation of the uniform film with a nanosheet structure offers high electrical conductivity and unobstructed access for the diffusion of triiodide to available electroactive sites, resulting in excellent device performance with superior long-term stability over 1000 h under natural conditions.

20.
Chem Sci ; 11(3): 748-756, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34123048

RESUMO

Sialylated glycans that are attached to cell surface mediate diverse cellular processes such as immune responses, pathogen binding, and cancer progression. Precise determination of sialylated glycans, particularly their linkage isomers that can trigger distinct biological events and are indicative of different cancer types, remains a challenge, due to their complicated composition and limited structural differences. Here, we present a biomimetic nanochannels system integrated with the responsive polymer polyethyleneimine-g-glucopyranoside (Glc-PEI) to solve this problem. By using a dramatic "OFF-ON" change in ion flux, the nanochannels system achieves specific recognition for N-acetylneuraminic acid (Neu5Ac, the predominant form of sialic acid) from various monosaccharides and sialic acid species. Importantly, different "OFF-ON" ratios of the conical nanochannels system allows the precise and sensitive discrimination of sialylated glycan linkage isomers, α2-3 and α2-6 linkage (the corresponding ion conductance increase ratios are 96.2% and 264%, respectively). Analyses revealed an unusual tug-of-war mechanism between polymer-glycan binding and polymer shrinkage. The low binding affinity of Glc-PEI for the α2-6-linked glycan caused considerable shrinkage of Glc-PEI layer, but the high affinity for the α2-3-linked glycan resulted in only a slight shrinkage. This competition mechanism provides a simple and versatile materials design principle for recognition or sensing systems that involve negatively charged target biomolecules. Furthermore, this work broadens the application of nanochannel systems in bioanalysis and biosensing, and opens a new route to glycan analysis that could help to uncover the mysterious and wonderful glycoworld.

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