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1.
Anal Chim Acta ; 1303: 342528, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38609267

RESUMO

Matrix deposition plays a critical role in image quality of matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). To improve the ionization efficiency and overcome the limitation of traditional matrix deposition methods in the face of difficult-to-sublimate or difficult-to-dissolve matrix, covalent organic frameworks (COFs) named COF-DhaTab was successfully synthesized and firstly used as matrix film. It was fabricated by imprinting of sieved COF-DhaTab powder on the surface of a double-sided adhesive tape. Outstanding reproducibility and uniformity of COF-DhaTab film were demonstrated by relative standard deviation (RSD) within 8.37% and 7.71% from dot-to-dot and plate-to-plate, respectively. With the introduction of double-sided adhesive tape, water contact angle (WCA) of COF-DhaTab film increased from 55° to 141°, resulting in significant suppression of analyte diffusion. Moreover, the intensity of potassium perfluorooctanic sulfonate (PFOS, C8F17SO3-, m/z 498.93) was 9.3 × 105, more than six hundred times higher than that using DHB matrix. This enhancement was attributed to the rough surface and multiple branches of the synthesized COF-DhaTab. To verify the ability of COF-DhaTab film as substrate, the spatial distribution of PFOS in zebrafish, rat liver and kidney tissues was explored. Superior imaging capability was displayed with high-spatial resolution and reliable location distribution. These results not only demonstrate the outstanding ability of COF-DhaTab as matrix for MALDI-MS and MALDI-MSI, but also provide a facile approach for fabrication of novel matrix films for MALDI-MSI.

2.
J Environ Manage ; 357: 120803, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38569268

RESUMO

Resuscitation promoting factors (Rpfs), known for their anti-dormancy cytokine properties, have been extensively investigated in the medical field. Although the Rpf from Micrococcus luteus has been successfully utilized to resuscitate and stimulate microbial populations for the degradation of polychlorinated biphenyls (PCBs), the presence of indigenous Rpf homologs in PCB-contaminated soils has not been established. In this study, the distribution characteristics of rpf-like genes and indigenous strain capable of producing Rpf in PCB-contaminated soils were explored. The results revealed the widespread presence of Rpf-like domains and their associated genes, particularly in close association with heavy metals and PCBs. The rpf-like genes were predominantly found in Proteobacteria and displayed a positive correlation with genes involved in PCB degradation and viable but non-culturable (VBNC) formation. Notably, the recombinant Rpf-Ac protein derived from the indigenous strain Achromobacter sp. HR2 exhibited muralytic activity and demonstrated significant efficacy in resuscitating the growth of VBNC cells, while also stimulating the growth of normal cells. These findings shed light on the prevalent presence of Rpf homologs in PCB-contaminated soils and their potential to resuscitate functional populations in the VBNC state, thereby enhancing in situ bioremediation.


Assuntos
Bifenilos Policlorados , Biodegradação Ambiental , Solo
3.
J Clin Neurosci ; 123: 72-76, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38547819

RESUMO

OBJECTIVES: The primary aim of this study is to explore the factors associated with delirium incidence in postoperative patients who have undergone endoscopic transsphenoidal approach surgery for pituitary adenoma. METHODS: The study population included patients admitted to Tianjin Huanhu Hospital's Skull Base Endoscopy Center from January to December 2022, selected through a retrospective cohort study design. The presence of perioperative delirium was evaluated using the 4 'A's Test (4AT) scale, and the final diagnosis of delirium was determined by clinicians. Statistical analysis included Propensity Score Matching (PSM), χ2 Test, and Binary Logistic Regression. RESULTS: A total of 213 patients were included in this study, and the incidence of delirium was found to be 29.58 % (63/213). Among them, 126 patients were selected using PSM (delirium:non-delirium = 1:1), ensuring age, gender, and pathology were matched. According to the results of univariate analysis conducted on multiple variables, The binary logistic regression indicated that a history of alcoholism (OR = 6.89, [1.60-29.68], P = 0.010), preoperative optic nerve compression symptoms (OR = 4.30, [1.46-12.65], P = 0.008), operation time ≥3 h (OR = 5.50, [2.01-15.06], P = 0.001), benzodiazepines for sedation (OR = 3.94, [1.40-11.13], P = 0.010), sleep disorder (OR = 3.86, [1.40-10.66], P = 0.009), and physical restraint (OR = 4.53, [1.64-12.53], P = 0.004) as independent risk factors for postoperative delirium following pituitary adenoma surgery. CONCLUSIONS: For pituitary adenoma patients with a history of alcoholism and presenting symptoms of optic nerve compression, as well as an operation time ≥3 h, enhancing communication between healthcare providers and patients, improving perioperative sleep quality, and reducing physical restraint may help decrease the incidence of postoperative delirium.


Assuntos
Adenoma , Delírio , Neoplasias Hipofisárias , Complicações Pós-Operatórias , Humanos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Neoplasias Hipofisárias/cirurgia , Adenoma/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Delírio/etiologia , Delírio/epidemiologia , Adulto , Fatores de Risco , Incidência , Idoso , Estudos de Coortes , Neuroendoscopia/efeitos adversos , Neuroendoscopia/métodos
4.
Food Chem ; 447: 139016, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38513494

RESUMO

Per- and polyfluoroalkyl substances (PFASs) are extensively found in foods, posing potential toxicity to humans. Therefore, rapid analysis and monitoring of PFASs in foods are crucial for public health and also a challenge. To detect trace PFASs in foods, construction of sorbents with multiple interactions could be an effective approach. Herein, a cationic-fluorinated covalent organic framework (CF-COF) was prepared by post-modification and used as a magnetic solid-phase extraction adsorbent for adsorption of PFASs. By combining magnetic solid-phase extraction based on CF-COF with liquid chromatography-tandem mass spectrometry (LC - MS/MS), a novel method was developed for determination of eight long-chain PFASs in foods. Under optimized conditions, the method exhibited low detection limits (0.003-0.019 ng/g) and satisfactory recovery rates (73.5-118%) for PFASs. This study introduces a novel idea for the development of adsorbents targeting PFASs, along with a new analytical method for monitoring of PFASs in foods.


Assuntos
Fluorocarbonos , Estruturas Metalorgânicas , Humanos , Espectrometria de Massas em Tandem/métodos , Estruturas Metalorgânicas/química , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Extração em Fase Sólida/métodos , Fluorocarbonos/análise , Limite de Detecção
5.
Talanta ; 273: 125877, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38460420

RESUMO

Pillar[n]arenes (P[n]A, n = 5-10) have attracted much attention because of their highly symmetric pillar-shaped architecture with π-electron rich cavity. Nevertheless, the use of ionic liquid functionalized P[n]A in chromatography has not been reported up to data. This work reports the investigation of the imidazolium ionic liquids functionalized pillar[6]arene (P6A-C10-IM-C8[NTf2]) as the stationary phase for gas chromatography (GC). The statically coated P6A-C10-IM-C8[NTf2] column (0.25 mm i.d.) showed moderate polarity and high column efficiency of 4733 plates/m determined by n-dodecane at 120 °C (k = 2.29). Owing to its unique amphiphilic conformation, the P6A-C10-IM-C8[NTf2] showed good column inertness and resolving capability for a wide range of analytes and isomers. Particularly, the P6A-C10-IM-C8[NTf2] column exhibited distinctly advantageous performance for the challenging isomers of halogenated benzenes, benzaldehydes, phenols and anilines over the common commercial columns, namely 5% phenyl methyl polysiloxane (HP-5) and 35% phenyl methyl polysiloxane (HP-35). In addition, it exhibited good column repeatability and reproducibility with RSD values on the retention times less than 0.05% for run-to-run, 0.38% for day-to-day and 2.94% for column-to-column, respectively. This work demonstrates the promising future of ionic liquid P[n]A stationary phases for chromatographic separations.

6.
Anal Chem ; 96(13): 5134-5142, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38507805

RESUMO

Mitochondria are important organelles that provide energy for cellular physiological activities. Changes in their structures may indicate the occurrence of diseases, and the super-resolution imaging of mitochondria is of great significance. However, developing fluorescent probes for mitochondrial super-resolution visualization still remains challenging due to insufficient fluorescence brightness and poor stability. Herein, we rationally synthesized an ultrabright xanthene fluorescence probe Me-hNR for mitochondria-specific super-resolution imaging using structured illumination microscopy (SIM). The rigid structure of Me-hNR provided its ultrahigh fluorescence quantum yield of up to 0.92 and ultrahigh brightness of up to 16,000. Occupying the para-position of the O atom in the xanthene skeleton by utilizing the smallest methyl group ensured its excellent stability. The study of the photophysical process indicated that Me-hNR mainly emitted fluorescence via radiative decay, and nonradiative decay and inter-system crossing were rare due to the slow nonradiative decay rate and large energy gap (ΔEst = 0.55 eV). Owing to these excellent merits, Me-hNR can specifically light up mitochondria at ultralow concentrations down to 5 nM. The unprecedented spatial resolution for mitochondria with an fwhm of 174 nm was also achieved. Therefore, this ultrabright xanthene fluorescence probe has great potential in visualizing the structural changes of mitochondria and revealing the pathogenesis of related diseases using SIM.


Assuntos
Corantes Fluorescentes , Xantenos , Corantes Fluorescentes/química , Mitocôndrias , Organelas , Microscopia de Fluorescência/métodos
7.
Nucleic Acids Res ; 52(6): 2808-2820, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38426933

RESUMO

Chemical modifications in RNAs play crucial roles in diversifying their structures and regulating numerous biochemical processes. Since the 1990s, several hydrophobic prenyl-modifications have been discovered in various RNAs. Prenyl groups serve as precursors for terpenes and many other biological molecules. The processes of prenylation in different macromolecules have been extensively studied. We introduce here a novel chemical biology toolkit that not only labels i6A, a prenyl-modified RNA residue, by leveraging the unique reactivity of the prenyl group, but also provides a general strategy to incorporate fluorescence functionalities into RNAs for molecular tracking purposes. Our findings revealed that iodine-mediated cyclization reactions of the prenyl group occur rapidly, transforming i6A from a hydrogen-bond acceptor to a donor. Based on this reactivity, we developed an Iodine-Mediated Cyclization and Reverse Transcription (IMCRT) tRNA-seq method, which can profile all nine endogenous tRNAs containing i6A residues in Saccharomyces cerevisiae with single-base resolution. Furthermore, under stress conditions, we observed a decline in i6A levels in budding yeast, accompanied by significant decrease of mutation rate at A37 position. Thus, the IMCRT tRNA-seq method not only permits semi-quantification of i6A levels in tRNAs but also holds potential for transcriptome-wide detection and analysis of various RNA species containing i6A modifications.


Assuntos
Isopenteniladenosina , Processamento Pós-Transcricional do RNA , RNA de Transferência , Iodo , Neopreno , RNA de Transferência/metabolismo , Saccharomyces cerevisiae , Análise de Sequência de RNA
8.
Anal Methods ; 16(12): 1748-1755, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38437029

RESUMO

In this study, a new type of covalent organic framework (TpBD) functionalized bivalved magnetic microsphere (TpBD-DS MNS) adsorbent was applied for the enrichment and detection of trace morphine and its metabolites in mouse urine. The main factors affecting the efficiency of magnetic solid phase extraction were optimized, and the optimal MSPE conditions were obtained. Combined with the UPLC-MS/MS technique, a new method for determining trace morphine and its metabolites in urine was established. The detection (LOD) and quantification (LOQ) limits for morphine and its metabolites ranged from 0.16 pg mL-1 to 0.53 pg mL-1 and 0.26 pg mL-1 to 1.25 pg mL-1, respectively. The recovery of the methods ranged from 87.4-97.3%, and the RSD was less than 5%. By employing this methodology, we successfully obtained the temporal change curve of morphine and its metabolites in mouse urine through collection and measurement post intravenous administration of morphine. This approach not only presents a novel means for investigating pharmacokinetics and drug monitoring but also demonstrates significant potential in the fields of forensic toxicology and drug abuse surveillance.


Assuntos
Morfina , Espectrometria de Massas em Tandem , Animais , Camundongos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida , Magnetismo , Fenômenos Magnéticos
9.
Chem Commun (Camb) ; 60(23): 3098-3117, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38406926

RESUMO

DNA nanostructures are easy to design and construct, have good biocompatibility, and show great potential in biosensing and drug delivery. Numerous distinctive and versatile DNA nanostructures have been developed and explored for biomedical applications. In addition to DNA nanostructures that are completely assembled from DNA, composite DNA nanostructures obtained by combining DNA with other organic or inorganic materials are also widely used in related research. The CRISPR/Cas system has attracted great attention as a powerful gene editing technology and is also widely used in biomedical diagnosis. Many researchers are committed to exploring new possibilities by combining DNA nanostructures with CRISPR/Cas systems. These explorations provide support for the development of new detection methods and cargo delivery pathways, provide inspiration for improving relevant gene editing platforms, and further expand the application scope of DNA nanostructures and CRISPR/Cas systems. This paper mainly reviews the design principles and biomedical applications of CRISPR/Cas combined with DNA nanostructures based on the types of DNA nanostructures. Finally, the application status, challenges and development prospects of CRISPR/Cas combined with DNA nanostructures in detection and delivery are summarized. It is expected that this review will enable researchers to better understand the current state of the field and provide insights into the application of CRISPR/Cas systems and the development of DNA nanostructures.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Sistemas de Liberação de Medicamentos , DNA
10.
Analyst ; 149(6): 1817-1824, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38345074

RESUMO

In this work, we develop a dual recycling amplification aptasensor for sensitive and rapid detection of lead ions (Pb2+) using fluorescence and surface-enhanced Raman scattering (FL-SERS). The aptasensor allows targeted cleavage of substrates through specifically binding with the Pb2+-dependent aptamer (M-PS2.M). Ultrasensitive detection of trace Pb2+ has been achieved using an enzyme-free nonlinear hybridization chain reaction (HCR) and the FL-SERS technique. The lower limit of detection (LOD = 3σ/k) is 0.115 pM in FL mode and 1.261 fM in SERS mode. The aptasensor is characterized by high reliability and specificity, among other things, to distinguish Pb2+ from other metal ions. In addition, the aptasensor can detect Pb2+ in actual water with good recovery. Compared with the single-mode aptasensor, the dual-mode aptasensor is characterized by high reliability, an extensive detection range, and high specificity.

11.
J Hazard Mater ; 465: 133409, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38211520

RESUMO

p-Phenylenediamine (PPD) antioxidants are heavily used for protection of commercial rubber products (e.g., vehicle tire), resulting in their widespread contamination in ecosystem. PPD-quinones (PPDQs), the toxic quinone derivatives of PPDs, are also discovered as novel environmental pollutants. However, the contamination characteristics of PPDs/PPDQs in fresh atmospheric snow (without deposition on the Earth surface) have seldom been studied. This work first reports the broad distributions of PPDs and PPDQs in fresh atmospheric snow collected from seven Chinese urban areas. Individual median values of detected concentrations were in the ranges of 0.4 to 260 pg g-1 (PPDs) and 0.7 to 104 pg g-1 (PPDQs). The concentration deviation by long-term deposition on the ground was eliminated. In most sampling regions, wearing of vehicle rubber tires was possibly responsible for spatial-dependent PPDs' pollution level variations, and high concentrations of PPDs promoted PPDQs' formation in snow from atmosphere. Yet, excessive O3 may further oxidize and reduce PPDQs in atmospheric fresh snow from Zhengzhou, which is different from previous research. Furthermore, snowfall was noticed might amplify concentrations of three PPDs and PPDQs in an inland lake, which possibly worsen corresponding pollution in water system. Current study elucidates the potential impacts of snow-bound PPDs/PPDQs on ecosystems should not be underestimated.

12.
Chem Commun (Camb) ; 60(14): 1912-1915, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38259117

RESUMO

We developed a multiplex single-molecule quantitative assay of intracellular telomerase that used target-triggered signal amplification to enhance sensitivity, substrate reaction to increase signal stability, and quantum dots to enhance signal-to-noise ratio, obtaining an LOD of 5 × 10-14 IU for intracellular telomerase and LOD of 3 cells for multiple cancer cells.


Assuntos
Técnicas Biossensoriais , Pontos Quânticos , Telomerase , Humanos , Telomerase/metabolismo , Células HeLa , Nanotecnologia
13.
Anal Chim Acta ; 1288: 342160, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38220292

RESUMO

BACKGROUND: The development of efficent chromatographic stationary phases (SP) with mixed-mode or multiple interactions in high-performance liquid chromatography (HPLC) for the separation of complex samples is a challenging task. Metal organic frameworks (MOFs)-based SP can provide desired multiple interactions and enable the separation of a diverse range of solutes, but have limitations of low column efficiency and poor stability. RESULTS: Herein, the hybrid MOFs@Covalent organic frameworks (COFs) materials were used as SP in HPLC due to their synergistic structural features. The SiO2@NH2-UiO-66@CTF SP was synthesized by integration of NH2-UiO-66 and covalent triazine framework (CTF) onto silica surface. Due to the unique structure of SiO2@NH2-UiO-66@CTF with hierarchical-pores, this column showed higher column efficiency (up to 49,369 plates m-1 for alkylbenzenes) than the reported columns packed with MOFs-based SP. Owing to the Zr4+-N coordination bonding between CTF and NH2-UiO-66, the structural stability of SiO2@NH2-UiO-66@CTF can be improved. Furthermore, this new column exhibited remarkable column stability with relative standard deviation of retention time of <0.40% after 400 injections. With the combined advantages of multifunctional properties, high column efficiency, and good stability, SiO2@NH2-UiO-66@CTF SP showed excellent selectivity for the separation of a variety of hydrophobic, aromatic, heteroatomic, and hydrophilic analytes. SIGNIFICANCE AND NOVELTY: This work not only offers a promising SP with multiple retention mechanisms for HPLC, but also provides an efficient strategy for development of high column efficiency MOFs-based SP with good stability. Moreover, the MOFs@COFs hybrid materials were expanded in application area through this study, and the research results can also afford the foundation for further explore its structural characteristics.

14.
Sci China Life Sci ; 67(1): 83-95, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37721637

RESUMO

SARS-CoV-2 continues to threaten human society by generating novel variants via mutation and recombination. The high number of mutations that appeared in emerging variants not only enhanced their immune-escaping ability but also made it difficult to predict the pathogenicity and virulence based on viral nucleotide sequences. Molecular markers for evaluating the pathogenicity of new variants are therefore needed. By comparing host responses to wild-type and variants with attenuated pathogenicity at proteome and metabolome levels, six key molecules on the polyamine biosynthesis pathway including putrescine, SAM, dc-SAM, ODC1, SAMS, and SAMDC were found to be differentially upregulated and associated with pathogenicity of variants. To validate our discovery, human airway organoids were subsequently used which recapitulates SARS-CoV-2 replication in the airway epithelial cells of COVID-19 patients. Using ODC1 as a proof-of-concept, differential activation of polyamine biosynthesis was found to be modulated by the renin-angiotensin system (RAS) and positively associated with ACE2 activity. Further experiments demonstrated that ODC1 expression could be differentially activated upon a panel of SARS-CoV-2 variants of concern (VOCs) and was found to be correlated with each VOCs' pathogenic properties. Particularly, the presented study revealed the discriminative ability of key molecules on polyamine biosynthesis as a predictive marker for virulence evaluation and assessment of SARS-CoV-2 variants in cell or organoid models. Our work, therefore, presented a practical strategy that could be potentially applied as an evaluation tool for the pathogenicity of current and emerging SARS-CoV-2 variants.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Multiômica , Putrescina
15.
J Sep Sci ; 47(1): e2300620, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38066235

RESUMO

Herein, a magnetic borate-functionalized MXene composite with multiple boronic affinity sites was fabricated by embedding Fe3 O4 nanoparticles with 4-formylphenylboronic acid functionalized Ti3 C2 Tx nanosheets and served as sorbent for the simultaneous extraction of catecholamines (CAs) in urine samples. The morphology and structure of the magnetic materials were investigated using scanning microscopy, vibrating sample magnetometer, X-ray photoelectron spectrometer, and X-ray diffraction. The introduction of polyethyleneimine can amplify the bonded boronic acid groups, thereby effectively improving the adsorption capacities for CAs based on the multiple interactions of boronic affinity, hydrogen bonding, and metal coordination. The adsorption performance was investigated using the kinetics and isotherms models, and the main parameters that influence the extraction efficiency were optimized. Under the most favorable magnetic solid-phase extraction condition, a sensitive method for the analysis of CAs in urine samples was developed by combining magnetic solid-phase extraction conditions with high-performance liquid chromatography detection. The findings illustrated that the proposed approach possessed a wide linearity range of 0.05-250 ng/mL with an acceptable correlation coefficient (R2  ≥ 0.9984) and detection limits of 0.010-0.015 ng/mL for the target CAs. The research not only provides a notable composite with multiple boronic affinity sites but also offers an effective and feasible measure for the detection of CAs in biological samples.


Assuntos
Catecolaminas , Nanopartículas de Magnetita , Nitritos , Elementos de Transição , Polietilenoimina/química , Adsorção , Ácidos Borônicos/química , Cromatografia Líquida de Alta Pressão , Extração em Fase Sólida , Nanopartículas de Magnetita/química , Fenômenos Magnéticos
16.
J Hazard Mater ; 465: 133242, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38103289

RESUMO

The resuscitated strains achieved through the addition of resuscitation promoting factor (Rpf) hold significant promise as bio-inoculants for enhancing the bioremediation of polychlorinated biphenyls (PCBs). Nevertheless, the potential of these resuscitated strains to transition into a viable but non-culturable (VBNC) state, along with the specific stressors that initiate this transformation, remains to be comprehensively elucidated. In this study, a resuscitated strain HR2, obtained through Rpf amendment, was employed to investigate its survival strategies under combined stress involving low temperature (LT), and PCBs, in the absence and presence of heavy metals (HMs). Whole-genome analysis demonstrated that HR2, affiliated with Achromobacter, possessed 107 genes associated with the degradation of polycyclic aromatic compounds. Remarkably, HR2 exhibited effective degradation of Aroclor 1242 and robust resistance to stress induced by LT and PCBs, while maintaining its culturability. However, when exposed to the combined stress of LT, PCBs, and HMs, HR2 entered the VBNC state. This state was characterized by significant decreases in enzyme activities and notable morphological, physiological, and molecular alterations compared to normal cells. These findings uncovered the survival status of resuscitated strains under stressful conditions, thereby offering valuable insights for the development of effective bioremediation strategies.


Assuntos
Bifenilos Policlorados , Compostos Policíclicos , Bifenilos Policlorados/metabolismo , Biodegradação Ambiental
17.
Artigo em Inglês | MEDLINE | ID: mdl-38044636

RESUMO

DNA nanomachines could initiate the cascade reaction in an autonomous mode under the drive of triggers, which achieve the signal amplification for the bioimaging of intracellular biomarkers. Compared with the "always-on" nanomachine that possibly produces false-positive signals, a controllable nanomachine with the on-site activation could be better for accurate tumor imaging and precise tumor therapy. Till now, the endogenous and exogenous triggers have been developed to design the controllable nanosensors. However, their combinations to develop feasible DNA nanomachines have been rarely studied. Herein, we constructed a near-infrared (NIR)-light-controlled DNA nanomachine that was first activated by the NIR light and then induced a target-triggered amplification process under the drive of an endogenous stimulus. Owing to adenosine-5'-triphosphate (ATP) having much higher concentration in cancer cells than that in healthy cells and the extracellular fluid, the obtained DNA nanomachine was selectively activated in cancer cells with inhibited interference signals from the surrounding healthy tissues. With obvious advantages including the exogenous NIR light initiation, the selective activation by the target microRNA, and the sensitive acceleration by the ATP-induced strand recycling reaction, the constructed nanomachine could be used to image the intracellular microRNA with increased sensitivity. Besides, after modifying the DNA sequence with the photosensitizer molecules, the obtained nanomachine could perform the selective photodynamic therapy on the tumor sections with the outstandingly decreased side effects. Thus, we hope the designed nanomachine could provide some important hints to design feasible nanomachines for accurate tumor diagnosis and precise tumor therapy.

18.
J Chromatogr A ; 1712: 464491, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37931428

RESUMO

Urinary hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) and catecholamines (CAs) are important biomarkers of PAHs exposure. In this study, a novel magnetic boronic acid hypercrosslinked composite (Fe3O4@HCP-BA) is synthesized using a facile one-pot strategy and applied as a sorbent for the simultaneous extraction of OH-PAHs and CAs in urine samples. The synthesized Fe3O4@HCP-BA composites are characterized by rich pore structure, highly specific surface area, good magnetic response, and excellent selectivity and adsorption efficiency (range: 65.26-496.71 and 1227.3-1581.8 µmol g-1 for CAs and OH-PAHs, respectively). The mechanisms governing the adsorption of the OH-PAHs and CAs to the Fe3O4@HCP-BA composites were systematically studied via adsorption kinetics, isotherm models, XPS characterization, and molecular simulation. The resultant Fe3O4@HCP-BA composite-based MSPE/HPLC-FLD method exhibited good linearity (R2 > 0.9916), low limits of detection (0.2-0.3 pg mL-1 and 0.2-0.3 ng mL-1 for OH-PAHs and CAs, respectively), and good precision (intra-day and inter-day RSDs < 11.1%). The analysis of CAs and OH-PAHs in the urine samples from 14 smokers and 14 non-smokers revealed a positive correlation between the concentrations of CAs and OH-PAHs. Our findings not only establish the proposed method as a green, environmentally friendly, and simple strategy for preparing magnetic adsorbents, but also confirm it as a promising alternative method for accurate determination of OH-PAHs and CAs in biological samples.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Extração em Fase Sólida , Extração em Fase Sólida/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Polímeros/química , Catecolaminas , Limite de Detecção , Fenômenos Magnéticos
19.
ACS Appl Bio Mater ; 6(11): 5086-5096, 2023 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-37943145

RESUMO

The autoluminescence nanoplatform based on a single-atom catalyst has the potential to achieve accurate tumor diagnosis and treatment. Taking advantage of this, glycyrrhetinic acid (GA) and chitosan-modified single Fe-N-C atom catalysts (SAF NPs) loaded with luminol-curcumin (Cur) were fabricated (SAF-LCCG). Once delivered to the tumor, this autoluminescence SAF-LCCG could target the mitochondria to restrain tumor metastasis and promote the production of hydrogen peroxide (H2O2). Then, SAF NPs with Fenton-like properties could actively utilize intracellular H2O2 to produce ·OH for chemodynamic therapy. After that, excess ·OH and H2O2 were transmitted to luminol to emit blue-violet chemiluminescence (CL) for cancer cell imaging. Synchronously, light was transferred to Cur to produce reactive oxygen species (ROS) which realized photodynamic therapy. Besides, Cur could be served as a chemotherapeutic drug to enhance intracellular ROS for penetrating therapy. More importantly, the massive accumulation of ROS in cancer cells can promote the CL intensity of luminol, which realized the cyclic ROS amplification. This autoluminescence nanoplatform was developed for accurate cancer cell imaging, effective inhibition of tumor metastasis, and synergistic and penetrated treatment of tumors.


Assuntos
Curcumina , Neoplasias , Humanos , Peróxido de Hidrogênio , Luminol , Espécies Reativas de Oxigênio , Curcumina/farmacologia , Curcumina/uso terapêutico , Mitocôndrias , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico
20.
J Agric Food Chem ; 71(46): 17999-18009, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37904272

RESUMO

Phthalate esters (PAEs) are widely distributed in the environment, and this has caused serious health and safety concerns. Development of rapid and ultrasensitive identification and analysis methods for phthalate esters is urgent and highly desirable. In this work, a novel nitrogen-rich covalent organic framework (N-TTI) derived quinoline bridging covalent organic framework (N-QTTI) was fabricated and used as a solid-phase microextraction (SPME) coating for the ultrasensitive determination of phthalate esters in water samples. The physical and chemical properties of N-QTTI were investigated sufficiently. The N-QTTI-coated fiber demonstrates a superior enrichment performance than either the N-TTI-coated fiber or commercial fibers under the optimized SPME conditions. For the first time, we propose a semi-immersion strategy for the extraction of PAEs from water samples based on N-QTTI-coated SPME fibers. Combined with gas chromatography-mass spectrometry (GC-MS), the developed method N-QTTI-SPME-GC-MS exhibits a wide linear range with a satisfactory linearity (R2 ≥ 0.995). The limits of detection (LOD, S/N = 3) and the limits of quantification (LOQs, S/N = 10) were 0.17-1.70 and 0.57-5.60 ng L-1, respectively. The repeatability of the new method was examined using relative standard deviations (RSDs) between intraday and interday data, which were 0.38-7.98% and 1.22-6.60%, respectively. The spiked recoveries at three levels of 10, 100, and 1000 ng L-1 were in the range of 90.0-106.2% with RSDs of less than 7.48%. The enrichment factors ranged from 291 to 17180. When compared to previously published works, the LODs of the newly established method were improved 5-5400 times, and the enrichment factors were increased by at least 8 times. The absorption mechanism was investigated by X-ray photoelectron spectroscopy and noncovalent interaction force analysis. The technique was successfully employed for detecting PAEs in water samples.


Assuntos
Estruturas Metalorgânicas , Ácidos Ftálicos , Quinolinas , Microextração em Fase Sólida/métodos , Estruturas Metalorgânicas/química , Ácidos Ftálicos/análise , Água/química , Ésteres/química
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