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1.
Anal Chem ; 96(5): 2173-2182, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38261544

RESUMO

Enantioselective discrimination of chiral molecules is essential in chemistry, biology, and medical science due to the configuration-dependent activities of enantiomers. Therefore, identifying a specific amino acid and distinguishing it from its enantiomer by using nanomaterials with outstanding performance are of great significance. Herein, blue- and green-emitting chiral silicon nanoparticles named bSiNPs and gSiNPs, respectively, with excellent water solubility, salt resistance, pH stability, photobleaching resistance, biocompatibility, and ability to promote soybean germination, were fabricated in a facile one-step method. Especially, chiral gSiNPs presented excellent fluorescence recognition ability for glutamic acid enantiomers within 1 min, and the enantiomeric recognition difference factor was as high as 9.0. The mechanism for enantiomeric fluorescence recognition was systematically explored by combining the fluorescence spectra with density functional theory (DFT) calculation. Presumably, the different Gibbs free energy and hydrogen-bonding interaction of the chiral recognition module with glutamic acid enantiomers mainly contributed to the difference in the fluorescence signals. Most noteworthy was the fact that the chiral gSiNPs can showcase not only the ability to recognize l- and d-glutamic acids in living cells but also the test strips fabricated by soaking gSiNPs can be applied for d-glutamic acid visual detection. As a result, this study provided insights into the design of multifunctional chiral sensing nanoplatforms for enantiomeric detection and other applications.


Assuntos
Ácido Glutâmico , Nanopartículas , Silício , Estereoisomerismo , Aminoácidos/química , Nanopartículas/química , Corantes
2.
Anal Bioanal Chem ; 416(4): 971-981, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38082135

RESUMO

Enzyme activity assays play a crucial role in numerous fields, including biotechnology, the food industry, and clinical diagnostics. Lipases are particularly important enzymes due to their widespread use in lipid metabolism and esterification reactions. Here, we present a pioneering method for the sensitive and selective determination of lipase activity using green carbon dots (G-CDs) for first time. G-CDs are a fascinating class of carbon nanomaterials with unique optical properties and biocompatibility, making them ideal candidates for enzyme activity assays. This approach eliminates the need for traditional fluorophores or chromogenic substrates, reducing costs, fast response time (1 min), and environmental impact with a quantum yield (QY) of 7.42%. As designed, the G-CDs fluorescent probe turn-on demonstrated a reliable linear detection range from 0 to 9 mg/mL under ideal conditions, with detection limit of 0.01 mg/mL and limit of quantification (LOQ) of 0.045 mg/mL, respectively. Furthermore, the G-CDs system was thoroughly evaluated in human serum samples, showing recoveries ranging from 100.0 to 105.0%. These findings highlight the promising applicability of the G-CDs probe for lipase detection, yielding highly favorable results.


Assuntos
Corantes Fluorescentes , Pontos Quânticos , Humanos , Corantes Fluorescentes/química , Carbono/química , Lipase , Pontos Quânticos/química , Espectrometria de Fluorescência
3.
Small ; 19(26): e2300013, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36942683

RESUMO

In optimizing perovskites with ionic liquid (IL), the comparative study on Lewis acid-base (LAB) and hydrogen-bonding (HB) interactions between IL and perovskite is lacking. Herein, methyl is substituted for hydrogen on 2-position of imidazolium ring of N-heterocyclic carbene (NHC) type IL IdH to weaken HB interactions, and the resulting N-heterocyclic olefin (NHO) type IL IdMe with softer Lewis base character is studied in both hybrid quasi-2D (Q-2D) and 3D perovskites. It is revealed that IdMe participates in constructing high-quality Q-2D perovskite (n = 4) and provides stronger passivation for 3D perovskite compared with IdH. Power conversion efficiency (PCE) of Q-2D PEA2 MA3 Pb4 I13 perovskite solar cells (PVSCs) is boosted to 17.68% from 14.03%. PCE and device stability of 3D PVSCs enhances simultaneously. Both theoretical simulations and experimental results show that LAB interactions between NHO and Pb2+ take the primary optimization effects on perovskite. The success of engineering LAB interactions also offers inspiration to develop novel ILs for high-performance PVSCs.

4.
Anal Bioanal Chem ; 415(18): 4255-4264, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36350343

RESUMO

In this work, phosphorus-doped carbon dots (P-DESCDs) were successfully prepared using choline chloride/lactic acid type deep eutectic solvent and phosphoric acid as ingredients, and (3-aminopropyl) trimethoxysilane was used as a bridge to graft P-DESCDs onto the silica surface to obtain a new mixed-mode stationary phase (Sil-P-DESCDs) for reversed-phase and hydrophilic interaction liquid chromatography. The successful preparation of the stationary phase was confirmed by laser scanning confocal microscopy, elemental analysis, and Fourier transform infrared spectrometry. Interestingly, the doping of phosphorus greatly improved the separation performance and hydrophilicity of the Sil-P-DESCDs column. The Sil-P-DESCDs column was found to have certain hydrophobicity, hydrogen bonding ability and shape selectivity by Tanaka and Engelhardt standard test mixtures, and a series of hydrophilic and hydrophobic compounds such as alkylbenzenes, polycyclic aromatic hydrocarbons, sulfonamides, aromatic amines, phenols, flavonoids, nucleoside bases, and alkaloids. In addition, the effects of mobile phase ratio, column temperature, flow rate, salt concentration, and pH on the retention of analytes on Sil-P-DESCDs columns were investigated. Finally, the Sil-P-DESCDs column was applied to the qualitative and quantitative analysis of calcein-7-glucoside in the real sample of medicinal Astragalus pellets, and it was found at a concentration of 0.02 mg/mL.


Assuntos
Solventes Eutéticos Profundos , Dióxido de Silício , Dióxido de Silício/química , Cromatografia de Fase Reversa/métodos , Carbono , Solventes , Interações Hidrofóbicas e Hidrofílicas
5.
Mikrochim Acta ; 190(6): 243, 2023 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-37247129

RESUMO

Mn3O4 nanoparticles composed of porous reduced graphene oxide nanosheets (Mn3O4@p-rGO) with enhanced oxidase-like activity were successfully fabricated through an in-situ approach for fast colorimetric detection of ascorbic acid (AA). The residual Mn2+ in the GO suspension of Hummers method was directly reused as the manganese source, improving the atom utilization efficiency. Benefiting from the uniform distribution of Mn3O4 nanoparticles on the surface of p-rGO nanosheets, the nanocomposite exhibited larger surface area, more active sites, and accelerated electron transfer efficiency, which enhanced the oxidase-like activity. Mn3O4@p-rGO nanocomposite efficiently activate dissolved O2 to generate singlet oxygen (1O2), leading to high oxidation capacity toward the substrate 3,3',5,5'-tetramethylbenzidine (TMB) without the extra addition of H2O2. Furthermore, the prominent absorption peak of the blue ox-TMB at 652 nm gradually decreased in the presence of AA, and a facile and fast colorimetric sensor was constructed with a good linear relationship (0.5-80 µM) and low LOD (0.278 µM) toward AA. Owing to the simplicity and excellent stability of the sensing platform, its practical application for AA detection in juices has shown good feasibility and reliability compared with HPLC and the 2, 4-dinitrophenylhydrazine colorimetric method. The oxidase-like Mn3O4@p-rGO provides a versatile platform for applications in food testing and disease diagnosis.


Assuntos
Nanopartículas , Oxirredutases , Colorimetria , Peróxido de Hidrogênio , Porosidade , Reprodutibilidade dos Testes , Ácido Ascórbico
6.
Int J Mol Sci ; 24(23)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38069368

RESUMO

Lung cancer is a malignant tumor with one of the highest morbidity and mortality rates in the world. Approximately 80-85% of lung cancer is diagnosed as non-small lung cancer (NSCLC), and its 5-year survival rate is only 21%. Cisplatin is a commonly used chemotherapy drug for the treatment of NSCLC. Its efficacy is often limited by the development of drug resistance after long-term treatment. Therefore, determining how to overcome cisplatin resistance, enhancing the sensitivity of cancer cells to cisplatin, and developing new therapeutic strategies are urgent clinical problems. Z-ligustilide is the main active ingredient of the Chinese medicine Angelica sinensis, and has anti-tumor activity. In the present study, we investigated the effect of the combination of Z-ligustilide and cisplatin (Z-ligustilide+cisplatin) on the resistance of cisplatin-resistant lung cancer cells and its mechanism of action. We found that Z-ligustilide+cisplatin decreased the cell viability, induced cell cycle arrest, and promoted the cell apoptosis of cisplatin-resistant lung cancer cells. Metabolomics combined with transcriptomics revealed that Z-ligustilide+cisplatin inhibited phospholipid synthesis by upregulating the expression of phospholipid phosphatase 1 (PLPP1). A further study showed that PLPP1 expression was positively correlated with good prognosis, whereas the knockdown of PLPP1 abolished the effects of Z-ligustilide+cisplatin on cell cycle and apoptosis. Specifically, Z-ligustilide+cisplatin inhibited the activation of protein kinase B (AKT) by reducing the levels of phosphatidylinositol 3,4,5-trisphosphate (PIP3). Z-ligustilide+cisplatin induced cell cycle arrest and promoted the cell apoptosis of cisplatin-resistant lung cancer cells by inhibiting PLPP1-mediated phospholipid synthesis. Our findings demonstrate that the combination of Z-Ligustilide and cisplatin is a promising approach to the chemotherapy of malignant tumors that are resistant to cisplatin.


Assuntos
Cisplatino , Neoplasias Pulmonares , Humanos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , 4-Butirolactona/farmacologia , Fosfolipídeos/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Apoptose , Linhagem Celular Tumoral , Proliferação de Células
7.
Molecules ; 28(4)2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36838529

RESUMO

Developing a simple and efficient method for removing organic micropollutants from aqueous systems is crucial. The present study describes the preparation and application, for the first time, of novel MXene-decorated bismuth ferrite nanocomposites (BiFeO3/MXene) for the removal of six sulfonamides including sulfadiazine (SDZ), sulfathiazole (STZ), sulfamerazine (SMZ), sulfamethazine (SMTZ), sulfamethoxazole (SMXZ) and sulfisoxazole (SXZ). The properties of BiFeO3/MXene are enhanced by the presence of BiFeO3 nanoparticles, which provide a large surface area to facilitate the removal of sulfonamides. More importantly, BiFeO3/MXene composites demonstrated remarkable sulfonamide adsorption capabilities compared to pristine MXene, which is due to the synergistic effect between BiFeO3 and MXene. The kinetics and isotherm models of sulfonamide adsorption on BiFeO3/MXene are consistent with a pseudo-second-order kinetics and Langmuir model. BiFeO3/MXene had appreciable reusability after five adsorption-desorption cycles. Furthermore, BiFeO3/MXene is stable and retains its original properties upon desorption. The present work provides an effective method for eliminating sulfonamides from water by exploiting the excellent texture properties of BiFeO3/MXene.


Assuntos
Nanocompostos , Poluentes Químicos da Água , Sulfonamidas , Bismuto , Sulfanilamida , Água , Adsorção , Poluentes Químicos da Água/análise , Cinética
8.
Anal Chem ; 94(15): 5970-5979, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35385268

RESUMO

The activity monitoring of acetylcholinesterase (AChE) and the screening of its inhibitors are critical for the diagnosis and therapy of neurological diseases. Herein, CeO2-Co(OH)2 nanosheets were synthesized for the first time in a newly designed deep eutectic solvent (DES) composed of l-proline and Ce(NO3)3·6H2O, and a colorimetric assay was developed for quantitative detection of AChE and anti-neurological disease drug screening. Impressively, CeO2-Co(OH)2 composites prepared in DESs have more prominent oxidase-like activity than Co(OH)2, CeO2, and CeO2-Co(OH)2 produced in aqueous solution. The mechanism study shows that the oxygen vacancies of CeO2-Co(OH)2 play a vital role in oxidase-like catalysis. Based on their excellent oxidase-like activity, the CeO2-Co(OH)2 nanosheets have been successfully applied for highly sensitive and selective detection of AChE with a linear range of 0.2-20 mU/mL. This strategy can also be used for inhibitor screening. The sensor displays an excellent linear response in the range of 0.001-2 µg/mL toward an irreversible inhibitor (paraoxon-ethyl). Moreover, five alkaloids, namely, berberine hydrochloride, caffeine, camptothecin, matrine, and evodiamine, were screened by using neostigmine bromide as a control; berberine hydrochloride exhibited a good inhibitory effect on AChE with an IC50 of 0.94 µM, while the other four had no obvious inhibitory effect. The mechanism of the different effects of alkaloids on inhibiting acetylcholinesterase activity was explored via molecular docking and kinetic simulation.


Assuntos
Alcaloides , Berberina , Acetilcolinesterase , Solventes Eutéticos Profundos , Avaliação Pré-Clínica de Medicamentos , Simulação de Acoplamento Molecular , Oxirredutases
9.
Langmuir ; 38(46): 14400-14408, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36350796

RESUMO

Surface modification is an effective way to functionalize the materials so as to get some special properties. Tetraphenylethylene (TPE) has been widely investigated as a well-known reagent which has the nature of aggregation-induced emission (AIE), but has never been reported in the liquid chromatography stationary phase. In this work, TPE-grafted silica (Sil-TPE) was obtained successfully using the derivative of 1-(4-hydroxyphenyl)-1,2,2-triphenylethylene as a ligand, and then characterized by elemental analysis, Fourier transform infrared spectra, thermogravimetric analysis, and so forth. Laser scanning confocal microscopy images reflected the AIE phenomenon of grafted TPE because the internal vibration and rotation of TPE molecules were restrained in the confined silica space. The contact angle test showed superhydrophobic properties of Sil-TPE. In order to understand thoroughly the mechanism of chromatographic performance and retention behavior for Sil-TPE, Tanaka test mixture, alkylbenzenes, polycyclic aromatic hydrocarbons (PAHs), and phenols were separated. This reveals that Sil-TPE has strong aromaticity and certain shape selectivity, especially, has excellent separation performance for PAHs and phenols. The thermodynamic properties and repeatability of Sil-TPE were further studied, which showed the stability of Sil-TPE. This work shows that TPE can be successfully grafted on silica surface and it has the potential to be a new kind of promising stationary phases in the future.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Dióxido de Silício , Dióxido de Silício/química , Cromatografia Líquida de Alta Pressão/métodos , Hidrocarbonetos Policíclicos Aromáticos/química , Fenóis
10.
Environ Res ; 214(Pt 4): 113977, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36027963

RESUMO

One of the key factors to obtain a highly pure individual rare earth element (REE) is to prepare adsorbents with high selectivity and adsorption capacity. Covalent organic frameworks (COFs), which encompass a variety of properties, including regular/tunable pore size, high specific surface area and easy functionalization, could be effective as adsorbents for separating rare earth elements (REEs). In this paper, TpPa COFs were successfully synthesized using an eco-friendly deep eutectic solvent (DES) as the reaction medium instead of toxic organic solvents at room temperature. TpPa COFs have a good separation effect on the nine REEs investigated in this work. Among them, the separation factors (ß) of Eu/Yb, Eu/Tm and Eu/La are 15.34, 14.70 and 10.78, respectively, indicating that the TpPa COFs have good separation performance. Further discoveries showed that the adsorption and separation mechanism of the TpPa COFs for REEs in this experiment may be due to the coordination of REE ions with O to form a stable structure. This study blazed a trial for a green and facile synthesis strategy of TpPa COFs and expanded its implementation as a solid adsorbent in the separation of REEs.

11.
Anal Chem ; 93(3): 1732-1739, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33355452

RESUMO

Rare earth elements (REEs) are used widely in devices of many fields, but it is still a troublesome task to achieve their selective separation and purification. Metal-organic frameworks (MOFs) as an emerging porous crystalline material have been used for selective separation of REEs using the size-selective crystallization properties. However, so far, almost all MOFs cannot be used directly for selective separation of REEs in strong acid via solid-state adsorption. Herein, a zinc-trimesic acid (Zn-BTC) MOF is grown by solid synthesis in situ on ZnO nanoparticles covering nanoporous graphene for preparing Zn-BTC MOF/nanoporous graphene composites with strong acid resistance. The adsorption capacity of the resulting composites to REEs is highly sensitive to the ionic radius, which may be attributed to the fact that the REE ions coordinate with O to form a stable structure. The selectivity of Ce/Lu is ≈10,000, and it is extremely important that the selectivity between adjacent REEs (e.g., Nd/Pr) is as high as ≈9.8, so the composite exhibits the best separation performance so far. This work provides a green, facile, scale, and effective synthesis strategy of Zn-BTC MOF/nanoporous graphene, which is hopefully applied directly in the separation industries of REEs.

12.
Anal Chem ; 93(48): 16175-16183, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34806872

RESUMO

Design and construction of a membrane that can achieve selective separation of uranium from spent fuel or seawater is a big challenge in the field of separation science. In this work, 1,3,5-benzenetricarboxylic acid (BTC) and three different nitrates (Zn/Ni/Cu) were used to prepare metal-organic frameworks (BTC-MOFs) with different pore sizes, and then, BTC-MOFs were intercalated into the interlayers of graphene oxide (GO) for preparing the composite membranes which presented selective separation of uranium with strong acid resistance. Composite membranes prepared by Zn/Ni/Cu-BTC-MOFs and GO can achieve the separation between ions of different valence states, and their permeability and selectivity depend on the membrane thickness, the acidity of driving solution, and the pore sizes of MOFs. Importantly, Cu-BTC-MOF-intercalated GO membranes can not only achieve the selective separation of Th4+ and UO22+ with a selectivity of ≈6 but also induce the ultra-high selectively separation of UO22+ and Ce3+ because the rejection rate of Ce3+ is about 100%. Moreover, the Zn-BTC-MOF-intercalated GO membrane shows an excellent selectivity of Th4+ and UO22+ with a selectivity of ≈25, and it may also achieve selective separation of uranium from seawater.

13.
Langmuir ; 37(41): 12242-12253, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34624195

RESUMO

An iron-nickel bimetallic oxide porous graphene composite material (Fe/Ni-PG) was prepared by a simple partial combustion method, which can be used to effectively remove sulfonamides (SAs) from an aqueous solution. The adsorption performance of Fe/Ni-PG, Fe-PG, and Ni-PG on six kinds of SAs was compared, and the influence of time, temperature, pH, and initial concentration of SAs on the adsorption behavior of SAs of Fe/Ni-PG in an aqueous solution was studied. The adsorption kinetics and thermodynamics exhibited that the Langmuir model and pseudo-second-order kinetics model can describe the adsorption isotherm and kinetics. The maximum adsorption capacities of sulfadiazine (SD), sulfamerazine (SM), sulfamethazine (SDM), sulfathiazole (STZ), sulfapyridine (SPD), and sulfisoxazole (SIZ) calculated by the Langmuir model were 26.3, 50.3, 42.2, 27.3, 34.5, and 41.7 mg/g, respectively, which exceeded those of most reported adsorbents. In the adsorption process, hydrogen bonding, π-π electron donor-acceptor, electrostatic interaction, and bimetallic synergies play a major role, and the entire adsorption process is spontaneously endothermic. In addition, the material has excellent stability, and the Fe/Ni-PG after desorption is consistent with the raw material. This work provides a favorable way for the removal of SAs in the environment.


Assuntos
Grafite , Poluentes Químicos da Água , Purificação da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Óxidos , Porosidade , Sulfonamidas , Termodinâmica , Poluentes Químicos da Água/análise
14.
Langmuir ; 37(35): 10529-10537, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34428054

RESUMO

Because abnormal acid phosphatase (ACP) can disrupt the normal physiological processes, determination of ACP level is extremely important for early diagnosis, treatment, and prognostic evaluation of diseases. Herein, a fluorescence platform for monitoring ACP level was established based on the assembly of red-emitting carbon dots (RCDs) on cobalt oxyhydroxide (CoOOH) nanoflakes. RCDs displayed excellent water solubility, pH stability, salt resistance, and photobleaching resistance. Interestingly, the fluorescence of the RCDs assembled on the surface of the CoOOH nanoflakes could be quenched due to the energy transfer caused by the nanoflakes. However, the ascorbic acid (AA) produced by the hydrolysis of ascorbic acid-2-phosphate trisodium salt (AAP) catalyzed by ACP could quickly and effectively reduce CoOOH nanoflakes, leading to the fluorescence recovery of the RCDs. Therefore, an "off-on" biosensor platform for rapid, sensitive, and selective detection of ACP was constructed with a limit of detection of 0.25 mU/L. With the assistance of the biosensor, the level of ACP in human serum samples was evaluated, and the spike recovery values ranged from 94.0% to 104.5%.


Assuntos
Técnicas Biossensoriais , Carbono , Fosfatase Ácida , Ácido Ascórbico , Cobalto , Corantes Fluorescentes , Humanos , Óxidos
15.
Mikrochim Acta ; 188(3): 80, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33576899

RESUMO

In recent years, significant efforts have been devoted towards the fabrication and application of layered double hydroxides (LDHs) due to their tremendous features such as excellent biocompatibility with negligible toxicity, large surface area, high conductivity, excellent solubility, and ion exchange properties. Most impressive, LDHs offer a favorable environment to attach several substances such as quantum dots, fluorescein dyes, proteins, and enzymes, which leads to strengthening the catalytic properties or increasing the sensing selectivity and sensitivity of the resulted hybrids. With the extensive ongoing research on the application of nanomaterials, many studies have led to remarkable achievements in exploring LDHs as sensing nanoplatforms. In optical sensors, for instance, many sensing strategies were tailored based on the enzyme-mimicking properties of LDHs, including colorimetric and chemiluminescence procedures. Meanwhile, others were designed based on intercalating some fluorogenic substrates on the LDHs, whereby the sensing signal can be acquired by quenching or enhancing their fluorescence after the addition of analytes. In this review, we aim to summarize the recent advances in optical sensors that use layered double hydroxides as sensing platforms for the determination of various analytes. By outlining some representative examples, we accentuate the change of spectral absorbance, chemiluminescence, and photoluminescence phenomena triggered by the interaction of LDH or functionalized-LDH with the indicators and analytes in the system. And finally, current limitations and possible future orientation in designing further LDHs-based optical sensors are presented. It is hoped that this review will be helpful in assisting the establishment of more improved sensors based on LDHs features. Optical sensors based on layered double hydroxides (LDHs) nanoplatforms were reviewed. The sensing system and detection approaches were rationally reviewed. Possible future orientations were highlighted.


Assuntos
Colorimetria/métodos , Fluorometria/métodos , Hidróxidos/química , Nanoestruturas/química , Espectrofotometria Ultravioleta/métodos , Adsorção , Fluorescência , Humanos , Hidróxidos/síntese química
16.
Anal Chem ; 92(20): 13630-13633, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-32830488

RESUMO

Chiral materials are usually the key to the separation of chiral membranes. In this work, we propose a new strategy that chiral porous graphene membrane can be fabricated from nonchiral porous graphene by mechanical stirring to induce vortex structure. Porous graphene with controlled, nanosized pores was synthesized by a newly designed, one-pot process directly from graphite as opposed to graphene oxide. Then porous graphene was immobilized on ultrafiltration membrane through filtering while stirring to form porous graphene membrane, which was applied for enantioselective separation toward DL-amino acids: for example, the separation factor of l-/d-phenylalanine reached 4.76. Interestingly, we first observed that the front and back sides of the porous graphene membrane exhibited opposite optical activities.

17.
Anal Chem ; 92(5): 3949-3957, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32054267

RESUMO

As an important chiral molecule for the preparation of levofloxacin, the optical purity of L-aminopropanol has a crucial effect on the pharmacology and pharmacodynamics of levofloxacin. Therefore, it is of great significance to discriminate D-aminopropanol and L-aminopropanol. In this paper, an effective aminopropanol enantiomer recognition method was established on the basis of the chiral fluorescent silicon nanoparticles (SiNPs) probe. The chiral fluorescent SiNPs were fabricated via a one-step aqueous solution synthesis strategy, which avoided multiple steps, pressurizing operation, and time-consuming postmodified procedures. Significantly, D-aminopropanol could significantly enhance the fluorescence of the chiral SiNPs, while L-aminopropanol could not affect the fluorescence of the chiral SiNPs. This could have occurred because of the stronger interaction between the chiral SiNPs and D-aminopropanol than that of L-aminopropanol. Thus, the rapid and selective recognition of the aminopropanol enantiomer was ideally realized. The mechanism of the chiral SiNPs recognizing aminopropanol was simulated by density functional theory quantum mechanical calculations. Interestingly, this was also proved by the separation of aminopropanol enantiomer using this chiral SiNPs-modified silica column in normal phase liquid chromatography. To the best of our knowledge, this is the first time that the chiral fluorescent SiNPs were synthesized and used to detect the aminopropanol enantiomer successfully. This work will inspire additional syntheses of chiral silicon nanomaterials and other nanomaterials with excellent properties and will enable application of chiral nanomaterials to other fields.


Assuntos
Nanopartículas/química , Propanolaminas/química , Silício/química , Cromatografia Líquida de Alta Pressão , Teoria da Densidade Funcional , Corantes Fluorescentes/química , Propanolaminas/isolamento & purificação , Dióxido de Silício/química , Espectrometria de Fluorescência , Estereoisomerismo , Temperatura
18.
Analyst ; 145(3): 1056-1061, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31845935

RESUMO

Red emitting carbon dots derived from p-phenylenediamine (PPDCDs) were successfully prepared and grafted onto the surface of silica spheres, which served as a new stationary phase (Sil-PPDCDs) for liquid chromatography with excellent hydrophilic selectivity. Various hydrophilic analytes including nucleosides and bases, amino acids, saccharides and ginsenosides can be well separated on this stationary phase. Compared with the precursor-modified silica, i.e. p-phenylenediamine functionalized silica stationary phase (Sil-PPD), Sil-PPDCDs possessed enhanced selectivity for the separation of tested polar compounds. Moreover, compared with two commercially available hydrophilic columns, the selective behavior of the stationary phase was also considerable. The successful application of the Sil-PPDCDs stationary phase again indicated the great potential of carbon dots as a new modifier of the stationary phase in high performance liquid chromatography, and this kind of new stationary phase is very promising to be used for the separation of hydrophilic compounds in biochemical and pharmaceutical analysis.

19.
Anal Bioanal Chem ; 412(19): 4629-4638, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32436032

RESUMO

In the quest for alternative products that would conquer natural enzyme drawbacks, enzyme-like nanomaterials with controllable morphology, high catalytic activity, excellent stability, and reusability have gained extensive attention in recent years. Herein, a simple and versatile strategy based on basic deep eutectic solvents was used to create layered copper hydroxide nitrate (Cu2(OH)3NO3) with a well-structured nanosheet-like morphology. The present nanosheets exhibited extraordinary oxidase and peroxidase-like activity. More importantly, these nanosheets have shown the ability to operate at low and high temperatures with appreciable stability and multiple reusabilities. Based on inhibiting the oxidase-like activity of the prepared Cu2(OH)3NO3, we designed a colorimetric sensing technique with a high-efficiency detection of biothiols in serum samples. Because of the simplicity and low-cost fabrication approach, our findings would be beneficial to the artificial enzyme research community as another facile and green tactics to fabricate heterogeneous artificial enzymes. Graphical abstract.


Assuntos
Cobre/química , Cisteína/sangue , Glutationa/sangue , Homocisteína/sangue , Hidróxidos/química , Nanoestruturas/química , Nitratos/química , Materiais Biomiméticos/química , Colorimetria/métodos , Humanos , Hidróxidos/síntese química , Nanotecnologia , Nitratos/síntese química , Oxirredutases/química , Solventes
20.
Chirality ; 32(3): 387-399, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31965651

RESUMO

A novel biselector bonded-type multifunctional chiral stationary phase (MCSP) was prepared by covalently crosslinking dialdehyde cellulose (DAC) with 6-monodeoxy-6-monoamino-ß-cyclodextrine (CD) via Schiff base reaction. The biselector bonded-type MCSP had good chiral and achiral chromatographic performance in normal phase (NP) and reversed phase (RP) modes. Seven and eight enantiomers were successfully separated on the prepared biselector bonded-type MCSP in NP and RP modes, respectively. The biselector bonded-type MCSP showed enhanced chiral resolution ability compared with single selector chiral stationary phases due to the simultaneous introduction of DAC and 6-monodeoxy-6-monoamino-ß-CD on the surface of silica gel. Aromatic compounds including polycyclic aromatic hydrocarbons, anilines, phenols, phenylates, and aromatic acids were choosed as analytes to investigate the achiral chromatographic performance of the biselector bonded-type MCSP in NP and RP modes. Chromatographic evaluation results showed that the above aromatic compounds were essentially capable of achieving baseline separation by hydrophobic interaction, π-π interaction, and π-π electron-donor-acceptor interaction. Moreover, the host-guest inclusion effect of 6-monodeoxy-6-monoamino-ß-CD and the multiple interactions made the biselector bonded-type MCSP have good steric selectivity. The preparation method of the biselector bonded-type MCSP was simple and provided a new idea and strategy for the preparation of the subsequent novel biselector MCSP.

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