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Biosensors Mar 2024Covalent organic frameworks (COFs) are porous crystals that have high designability and great potential in designing, encapsulating, and immobilizing nanozymes. COF... (Review)
Review
Covalent organic frameworks (COFs) are porous crystals that have high designability and great potential in designing, encapsulating, and immobilizing nanozymes. COF nanozymes have also attracted extensive attention in analyte sensing and detection because of their abundant active sites, high enzyme-carrying capacity, and significantly improved stability. In this paper, we classify COF nanozymes into three types and review their characteristics and advantages. Then, the synthesis methods of these COF nanozymes are introduced, and their performances are compared in a list. Finally, the applications of COF nanozymes in environmental analysis, food analysis, medicine analysis, disease diagnosis, and treatment are reviewed. Furthermore, we also discuss the application prospects of COF nanozymes and the challenges they face.
Topics: Metal-Organic Frameworks; Biosensing Techniques; Nanostructures; Chemistry, Analytic; Food Analysis; Chemistry Techniques, Analytical
PubMed: 38667156
DOI: 10.3390/bios14040163 -
Journal of the American Chemical Society Nov 2023Molecular materials are poised to play a significant role in the development of future optoelectronic and quantum technologies. A crucial aspect of these areas is the...
Molecular materials are poised to play a significant role in the development of future optoelectronic and quantum technologies. A crucial aspect of these areas is the role of spin-phonon coupling and how it facilitates energy transfer processes such as intersystem crossing, quantum decoherence, and magnetic relaxation. Thus, it is of significant interest to be able to accurately calculate the molecular spin-phonon coupling and spin dynamics in the condensed phase. Here, we demonstrate the maturity of methods for calculating spin-phonon coupling by performing a case study on a single-molecule magnet and showing quantitative agreement with the experiment, allowing us to explore the underlying origins of its spin dynamics. This feat is achieved by leveraging our recent developments in analytic spin-phonon coupling calculations in conjunction with a new method for including the infinite electrostatic potential in the calculations. Furthermore, we make the first determination of phonon lifetimes and line widths for a molecular magnet to prove that the commonplace Born-Markov assumption for the spin dynamics is valid, but such "exact" phonon line widths are not essential to obtain accurate magnetic relaxation rates. Calculations using this approach are facilitated by the open-source packages we have developed, enabling cost-effective and accurate spin-phonon coupling calculations on molecular solids.
PubMed: 37917936
DOI: 10.1021/jacs.3c06015 -
Biophysical Journal Aug 2023The endoplasmic reticulum (ER) is a dynamic network of interconnected sheets and tubules that orchestrates the distribution of lipids, ions, and proteins throughout the...
The endoplasmic reticulum (ER) is a dynamic network of interconnected sheets and tubules that orchestrates the distribution of lipids, ions, and proteins throughout the cell. The impact of its complex, dynamic morphology on its function as an intracellular transport hub remains poorly understood. To elucidate the functional consequences of ER network structure and dynamics, we quantify how the heterogeneity of the peripheral ER in COS7 cells affects diffusive protein transport. In vivo imaging of photoactivated ER membrane proteins demonstrates their nonuniform spreading to adjacent regions, in a manner consistent with simulations of diffusing particles on extracted network structures. Using a minimal network model to represent tubule rearrangements, we demonstrate that ER network dynamics are sufficiently slow to have little effect on diffusive protein transport. Furthermore, stochastic simulations reveal a novel consequence of ER network heterogeneity: the existence of "hot spots" where sparse diffusive reactants are more likely to find one another. ER exit sites, specialized domains regulating cargo export from the ER, are shown to be disproportionately located in highly accessible regions, further from the outer boundary of the cell. Combining in vivo experiments with analytic calculations, quantitative image analysis, and computational modeling, we demonstrate how structure guides diffusive protein transport and reactions in the ER.
Topics: Kinetics; Endoplasmic Reticulum; Protein Transport; Biological Transport; Proteins
PubMed: 37401053
DOI: 10.1016/j.bpj.2023.06.022 -
Global Epidemiology Jun 2024Evidence triangulation may help identify the impact of study design elements on study findings and to tease out biased results when evaluating potential causal...
Evidence triangulation may help identify the impact of study design elements on study findings and to tease out biased results when evaluating potential causal relationships; however, methods for triangulating epidemiologic evidence are evolving and have not been standardized. Building upon key principles of epidemiologic evidence triangulation and risk of bias assessment, and responding to the National Academies of Sciences, Engineering, and Medicine (NASEM) call for applied triangulation examples, the objective of this manuscript is to propose a triangulation framework and to apply it as an illustrative example to epidemiologic studies examining the possible relationship between occupational formaldehyde exposure and risk of myeloid leukemias (ML) including acute (AML) and chronic (CML) types. A nine-component triangulation framework for epidemiological evidence was developed incorporating study quality and ROB guidance from various federal health agencies (i.e., US EPA TSCA and NTP OHAT). Several components of the triangulation framework also drew from widely used epidemiological analytic tools such as stratified meta-analysis and sensitivity analysis. Regarding the applied example, fourteen studies were identified and assessed using the following primary study quality domains to explore potential key sources of bias: 1) study design and analysis; 2) study participation; 3) exposure assessment; 4) outcome assessment; and 5) potential confounding. Across studies, methodological limitations possibly contributing to biased results were observed within most domains. Interestingly, results from one study - often providing the largest and least-precise relative risk estimates, likely reflecting study biases, deviated from most primary study findings indicating no such associations. Triangulation of epidemiological evidence appears to be helpful in exploring inconsistent results for the identification of study results possibly reflecting various biases. Nonetheless, triangulation methodologies require additional development and application to real-world examples to enhance objectivity and reproducibility.
PubMed: 38659700
DOI: 10.1016/j.gloepi.2024.100143 -
Antibiotics (Basel, Switzerland) Oct 2023The research into new pharmaceutical substances based on essential oils, individual biologically active phytochemicals, and plant extracts is a priority in field of...
The research into new pharmaceutical substances based on essential oils, individual biologically active phytochemicals, and plant extracts is a priority in field of pharmaceutical sciences. A novel multicomponent substance based on () leaf oil (TTO), 1,8-cineole (eucalyptol), and (-)-α-bisabolol with potent synergetic antimicrobial activity was investigated and suggested for the treatment of seborrheic dermatitis (SD) and dandruff. The objective of this research was to establish and validate a specific, accurate, and precise gas chromatography-mass spectrometry (GC-MS) method for further quantitative and qualitative analysis in order to ensure quality control. The main parameters of validation were suitability, specificity, linearity, accuracy, and intermediate precision according to the (XI edition), (XIV edition), and some parameters of ICH requirements. The peaks of fifteen chemical phytoconstituents were identified in the test sample solution with the prevalence of (-)-α-bisabolol (27.67%), 1,8-cineole (25.63%), and terpinen-4-ol (16.98%). These phytochemicals in the novel substance were chosen for standardization and validation of the GC-MS method. The chosen chromatographic conditions were confirmed for testing of the plant-based substance in a suitability test. It was established that the GC-MS method provides a significant separation, symmetry of peaks and resolution between phytochemicals. The calibration curves of each phytochemical had good linearity (R > 0.999) in five concentrations. In the same concertation range, the accuracy of terpinen-4-ol, 1,8-cineol, and (-)-α-bisabolol determination using the method of additives was 98.3-101.60%; the relative standard deviation (RSD) ranged from 0.89% to 1.51% and corresponded to requirements. The intraday and interday precision was ≤2.56%. Thus, the GC-MS method was validated to be specific, sensitive, linear, accurate, and precise. This GC-MS method could be recommended as a routine analytic technique for multicomponent plant-based substances-enriched terpenes.
PubMed: 37887259
DOI: 10.3390/antibiotics12101558 -
Nanomaterials (Basel, Switzerland) Sep 2023Herein, we present a new heterogeneous catalyst active toward glucose to formic acid methyl ester oxidation. The catalyst was fabricated via electrostatic immobilization...
Herein, we present a new heterogeneous catalyst active toward glucose to formic acid methyl ester oxidation. The catalyst was fabricated via electrostatic immobilization of the inorganic polyoxometalate HPA-5 catalyst H[PMoVO] onto the pore surface of amphiphilic block copolymer membranes prepared via non-solvent-induced phase separation (NIPS). The catalyst immobilization was achieved via wet impregnation due to strong coulombic interactions between protonated tertiary amino groups of the polar poly(2-(dimethylamino)ethyl methacrylate) block and the anionic catalyst. Overall, three sets of five consecutive catalytic cycles were performed in an autoclave under 90 °С and 11.5 bar air pressure in methanol, and the corresponding yields of formic acid methyl ester were quantified via head-space gas chromatography. The obtained results demonstrate that the membrane maintains its catalytic activity over multiple cycles, resulting in high to moderate yields in comparison to a homogeneous catalytic system. Nevertheless, presumably due to leaching, the catalytic activity declines over five catalytic cycles. The morphological and chemical changes of the membrane during the prolonged catalysis under harsh conditions were examined in detail using different analytic tools, and it seems that the underlying block copolymer is not affected by the catalytic process.
PubMed: 37764527
DOI: 10.3390/nano13182498 -
PloS One 2023The material study of ancient Egyptian paintings began with the advent of Egyptology during the 19th century. By the 1930s, a lot had already been sampled and described....
The material study of ancient Egyptian paintings began with the advent of Egyptology during the 19th century. By the 1930s, a lot had already been sampled and described. The limited palette for example has been analysed from actual painted surfaces but also from pigments and painting tools retrieved on site. However, most of these studies took place in museums while the painted surfaces, preserved in funerary chapels and temples, remained somewhat estranged from this primary physical understanding. The artistic process has been also reconstructed, mainly from the information presented by unfinished monuments, showing surfaces at different stages of completion. A lot of this modern and theoretical reconstruction is, however, based on the usual archaeological guessing game that aims at filling the remaining blanks. Our interdisciplinary project has decided to experiment on-site with state-of-the-art portable analysis tools, avoiding any physical sampling, to see if our knowledge of the work of the ancient Egyptian painters and draughtsmen could be taken at a further stage, while based on physical quantification that could be seen as a stronger and more reliable foundation for a redefined scientific hypothesis. The use of XRF mapping has, for instance, been applied to a known case of correction by surface repaint, something that is supposedly rare in the ancient Egyptian formal artistic process, while another fully unexpected one was discovered during the analytic exploration of a royal representation. In both cases, the precise and readable imaging of the physical composition of the painted surface offers a renewed visual approach based of chemistry, that can be shared through a multi- and interdisciplinary approach. However, this also leads to a more complex description of pigment mixtures that could have multiple meanings, where the practical often leads towards the symbolic, and from there hopefully to a renewed definition of the use of colours in complex sets of ancient Egyptian representations. At this stage, though the progress in this on-site material assessment of ancient works of art definitely means astonishing progress, one humbly has to face the fact that these ancient treasures shall still retain part of their defining mysteries.
Topics: Paintings; Egypt; Paint; Archaeology; Head
PubMed: 37437004
DOI: 10.1371/journal.pone.0287647 -
ACS Omega Jan 2024In this paper, NiSb/NiTe/Ni composites were smoothly developed via the microwave method for supercapacitors. The synthesis of NiSb/NiTe crystals was revealed by X-ray...
In this paper, NiSb/NiTe/Ni composites were smoothly developed via the microwave method for supercapacitors. The synthesis of NiSb/NiTe crystals was revealed by X-ray photoelectron spectroscopy and X-ray diffraction. The analytic results of scanning electron microscopy and energy dispersive spectroscopy uncover the microscopic morphology as well as the constituent elements of the composites. Self-supported NiSb/NiTe is a supercapacitor cathode that combines high capacitance with excellent cycling stability. The obtained composite electrode displayed remarkable electrochemical properties, presenting a special capacitance of 1870 F g (1 A g) and 81.5% of the original capacity through 30,000 times (10 A g) of the charging/discharging process. Further, an asymmetric supercapacitor was prepared employing NiSb/NiTe as a cathode and activated carbon as an anode. NiSb/NiTe//AC exhibited a high energy density of 224.6 uW h cm with a power density of 750 μW cm and provided a favorable cycling stability of 83% after 10,000 cycles.
PubMed: 38250415
DOI: 10.1021/acsomega.3c07385 -
Discover Nano Sep 2023Although porphyry systems like metallo-phthalocynine are recognized as promising molecular models for electrocatalytic oxygen reduction reaction (ORR), their poor...
Although porphyry systems like metallo-phthalocynine are recognized as promising molecular models for electrocatalytic oxygen reduction reaction (ORR), their poor durability and methanol tolerance are still challenges and need improvement before being considered for practical applications. Herein, we successfully designed and constructed a Fe-phthalocyanine-derived highly conjugated 2D covalent organic framework (2D FePc-COF), using octa-amino-Fe-phthalocyanine (OA-FePc) and cyclohexanone as precursors. The prepared 2D FePc-COF was characterized via multiple analytic techniques. The electrochemical studies indicated that prepared 2D FePc-COF was far more superior to OA-FePc and 20% Pt/C, displaying anodic shift of 100 and 50 mV (vs RHE) in formal potential, respectively. Moreover, this catalyst also demonstrated excellent methanol tolerance and durability (over 10,000 CV cycles). Theoretical investigations revealed that due to extended conjugation and elimination of electron donating groups (-NH), the shifting of dz-orbital (Fe) energy took nearer to π*-orbital (O), allowing optimum coupling of both the orbitals, thereby enhancing 4e ORR. This work demonstrates the art of molecular design, aiming at improving catalytic activity of macrocyclic molecular systems towards ORR.
PubMed: 37665422
DOI: 10.1186/s11671-023-03890-w -
Scientific Reports Dec 2023The procedures currently used for hepatitis B (HB) detection are not suitable for screening, clinical diagnosis, and point-of-care testing (POCT). Therefore, we...
The procedures currently used for hepatitis B (HB) detection are not suitable for screening, clinical diagnosis, and point-of-care testing (POCT). Therefore, we developed and tested a QCM-based immunosensor by surface modification with AuNP-PEIs to amplify the signal and provide an oriented-immobilization surface. The AuNP-PEIs were characterized by ICP-Mass, UV/Vis, DLS, FE-SEM, and ATR-FTIR. After coating AuNP-PEIs on the gold electrode surface, anti-HBsAg antibodies were immobilized using NHS/EDC chemistry based on response surface methodology (RSM) optimization. The efficiency of the immunosensor was assessed by human sera and data were compared to gold-standard ELISA using receiver-operating-characteristic (ROC) analysis. FE-SEM, AFM, EDS, and EDS mapping confirmed AuNP-PEIs are homogeneously distributed on the surface with a high density and purity. After antibody immobilization, the immunosensor exhibited good recognition of HBsAg with a calibration curve of ∆F = - 6.910ex + 10(R = 0.9905), a LOD of 1.49 ng/mL, and a LOQ of 4.52 ng/mL. The immunosensor yielded reliable and accurate results with a specificity of 100% (95% CI 47.8-100.0) and sensitivity of 100% (95% CI 96.2-100.0). In conclusion, the fabricated immunosensor has the potential as an analytic tool with high sensitivity and specificity. However, further investigations are needed to convert it to a tiny lab-on-chip for HB diagnosis in clinical samples.
Topics: Humans; Biosensing Techniques; Metal Nanoparticles; Polyethyleneimine; Gold; Quartz Crystal Microbalance Techniques; Immunoassay; Hepatitis B; Limit of Detection
PubMed: 38071203
DOI: 10.1038/s41598-023-48766-2