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1.
Small ; 20(3): e2305943, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37681501

RESUMO

Photoresponsive nitric oxide (NO)-releasing materials (NORMs) enable the spatiotemporal delivery of NO to facilitate their potential applications in physiological conditions. Here two novel metal-organic frameworks (MOFs)-based photoactive NORMs achieved by the incorporation of prefunctionalized NO donors into the photosensitive Fe-MOFs via a postmodification strategy is reported. The modified Fe-MOFs display superior photoactivity of NO release when exposed to visible light (up to 720 nm). Significantly, the visible-light-driven NO release properties are further corroborated by their efficient antibacterial performance.


Assuntos
Estruturas Metalorgânicas , Óxido Nítrico , Elétrons , Luz , Antibacterianos/farmacologia
2.
Chemistry ; 30(29): e202400215, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38530218

RESUMO

Recent advances in synthetic methods, combined with tip-induced on-surface chemistry, have enabled the formation of numerous cyclocarbon molecules. Here, we investigate computationally the experimentally studied C16 and C18 molecules as well as their van der Waals (vdW) complexes with several typical donor and acceptor molecules. Our results demonstrate a remarkable electron-withdrawing ability of cyclocarbon molecules. The vdW complexes of C16 and C18 exhibit a thermodynamically favorable photoinduced electron transfer (ET) from the donor partner to the cyclocarbons that occurs on a picosecond time scale. The lower reorganization energy of C16 compared to C18 leads to a significant acceleration of the ET reactions.

3.
Chemistry ; 30(17): e202303996, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38165074

RESUMO

Inorganic-organic hybrid materials are a kind of multiduty materials with high crystallinity and definite structures, built from functional inorganic and organic components with highly tunable photochemical properties. Perylenediimides (PDIs) are a kind of strong visible light-absorbing organic dyes with π-electron-deficient planes and photochemical properties depending on their micro-environment, which provides a platform for designing tunable and efficient hybrid photocatalytic materials. Herein, four radical-doped PDI-based crystalline hybrid materials, Cl4-PDI⋅SiW12O40 (1), Cl4-PDI⋅SiMo12O40 (2), Cl4-PDI⋅PW12O40 (3), and Cl4-PDI⋅PMo12O40 (4), were attained by slow diffusion of polyoxometalates (POMs) into acidified Cl4-PDI solutions. The obtained PDI-based crystalline hybrid materials not only exhibited prominent photochromism, but also possessed reactive organic radicals under ambient conditions. Furthermore, all hybrid materials could be easily photoreduced to their radical anions (Cl4-PDI⋅-), and then underwent a second photoexcitation to form energetic excited state radical anions (Cl4-PDI⋅-*). However, experiments and theoretical calculations demonstrated that the formed energetic Cl4-PDI⋅-* showed unusual POM-dependent photocatalytic efficiencies toward the oxidative coupling of amines and the iodoperfluoroalkylation of alkenes; higher photocatalytic efficiencies were found for hybrid materials 1 (anion: SiW12O40 4-) and 2 (anion: SiMo12O40 4-) compared to 3 (anion: PW12O40 3-) and 4 (anion: PMo12O40 3-). The photocatalytic efficiencies of these hybrid materials are mainly controlled by the energy differences between the SOMO-2 level of Cl4-PDI⋅-* and the LUMO level of the POMs. The structure-photocatalytic activity relationships established in present work provide new research directions to both the photocatalysis and hybrid material fields, and will promote the integration of these areas to explore new materials with interesting properties.

4.
Chemistry ; 30(53): e202402076, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-38949119

RESUMO

"Tandem" uncaging systems, in which a photolabile protecting group (PPG) is sensitized by an energy-harvesting antenna, may increase the photosensitivity of PPGs by several orders of magnitude for two-photon (2P) photorelease. Yet, they remain poorly accessible because of arduous multi-step synthesis. In this work, we design efficient tandem uncaging systems by (i) using a convenient assembly of the building blocks relying on click chemistry, (ii) introducing H-bonding induced proximity thus facilitating (iii) photoinduced electron transfer (PeT) as a cooperative mechanism. A strong two-photon absorber electron-donating quadrupolar antenna and various electron-accepting PPGs (mDEAC, MNI or MDNI) were clicked stepwise onto a "tweezer-shaped" pyrido-2,6-dicarboxylate platform whose H-bonding and π-stacking abilities were exploited to keep the antenna and the PPGs in close proximity. The different electron-accepting ability of the PPGs led to dyads with wildly different behaviors. Whilst the MDNI and MNI dyads showed poor dark stability or no photo-uncaging ability due to their too high electron-accepting character, the mDEAC dyad benefited from optimum redox potentials to promote PeT and slow down charge recombination, resulting in enhanced uncaging quantum yield (Φu=0.38) compared to mDEAC (Φu=0.014). This unique combination resulted in large 2P photo-sensitivity in the near-infrared window (240 GM at 710 nm).

5.
Chemphyschem ; 25(17): e202400264, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38776018

RESUMO

Picric acid (PA) is an important industrial feedstock and hence the release of industrial effluents without proper remediation results in its buildup in soil and water bodies. The adverse effects of PA accumulation in living beings necessitate the development of efficient methods for its detection and quantification. Herein, we describe pyrene-based fluorescent sensors for PA, where pyrene is appended with electron-withdrawing groups, malononitrile, and 2-(3-cyano-4,5,5-trimethylfuran-2(5H)-ylidene) malononitrile (DCDHF). These molecules displayed the typical emission of pyrene monomers, as well as a broad red-shifted emission resulting from an intramolecular charge transfer (ICT) in the excited state. Both the emissions displayed a turn-off response to PA with high selectivity and sensitivity and the lowest limit of detection was estimated as 27 nM. To prove the feasibility of on-site detection, test paper strips were prepared, which could detect PA up to 4.58 picograms. Using a combination of experimental and theoretical studies the mechanism of the detection was identified as primary/secondary inner filter effect, oxidative photoinduced electron transfer, or a combination of both depending on the excitation wavelength. Interestingly, the contribution of each of these mechanisms to the total quenching process varied with a change in the excitation wavelength.

6.
Photochem Photobiol Sci ; 23(4): 693-709, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38457118

RESUMO

Psoralens are eponymous for PUVA (psoralen plus UV-A radiation) therapy, which inter alia can be used to treat various skin diseases. Based on the same underlying mechanism of action, the synthetic psoralen amotosalen (AMO) is utilized in the pathogen reduction technology of the INTERCEPT® Blood System to inactivate pathogens in plasma and platelet components. The photophysical behavior of AMO in the absence of DNA is remarkably similar to that of the recently studied psoralen 4'-aminomethyl-4,5',8-trimethylpsoralen (AMT). By means of steady-state and time-resolved spectroscopy, intercalation and photochemistry of AMO and synthetic DNA were studied. AMO intercalates with a higher affinity into A,T-only DNA (KD = 8.9 × 10-5 M) than into G,C-only DNA (KD = 6.9 × 10-4 M). AMO covalently photobinds to A,T-only DNA with a reaction quantum yield of ΦR = 0.11. Like AMT, it does not photoreact following intercalation into G,C-only DNA. Femto- and nanosecond transient absorption spectroscopy reveals the characteristic pattern of photobinding to A,T-only DNA. For AMO and G,C-only DNA, signatures of a photoinduced electron transfer are recorded.


Assuntos
Ficusina , Furocumarinas , Ficusina/farmacologia , Ficusina/química , Furocumarinas/farmacologia , Furocumarinas/química , DNA/química , Análise Espectral
7.
Photochem Photobiol Sci ; 23(1): 93-105, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38133700

RESUMO

Photoinduced symmetry-breaking charge separation (SB-CS) results in the generation of charge carriers through electron transfer between two identical molecules, after photoexcitation of one of them. It is usually studied in systems where the two reacting moieties are covalently linked. Examples of photoinduced bimolecular SB-CS with organic molecules yielding free ions remain scarce due to solubility or aggregation issues at the high concentrations needed to study this diffusion-assisted process. Here we investigate the excited-state dynamics of perylene (Pe) at high concentrations in solvents of varying polarity. Transient absorption spectroscopy on the subnanosecond to microsecond timescales reveal that self-quenching of Pe in the lowest singlet excited state leads to excimer formation in all solvents used. Additionally, bimolecular SB-CS, resulting in the generation of free ions, occurs concurrently to excimer formation in polar media, with a relative efficiency that increases with the polarity of the solvent. Moreover, we show that SB-CS is most efficient in room-temperature ionic liquids due to a charge-shielding effect leading to a larger escape of ions and due to the high viscosity that disfavours excimer formation.

8.
J Fluoresc ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38773031

RESUMO

Assessing medication adherence through the determination of antihypertensive drugs in biological matrices holds significant importance. Amlodipine (AP), a potent antihypertensive medication extensively prescribed for hypertensive patients, is particularly noteworthy in this context. This article aims to introduce a rapid, simple, improved sensitivity, and reproducibility in detecting AP in its pure form, tablet formulation, and spiked human plasma than the other reported methods. The proposed method utilizes a fluorescence approach, relying on the inhibition of the intramolecular photoinduced electron transfer (PET) effect of the lone pair of the N-atom in the primary amino moiety of AP. This inhibition is achieved by acidifying the surrounding medium using 0.2 M acetic acid. By blocking PET, the target AP drug is sensitively detected, at [Formula: see text] 423 nm over a concentration range 25-500 ng mL- 1 showcasing an exceptionally low quantitation limit of 1.41 ng mL- 1. Notably, this innovative technique was successfully applied to detect AP in its solid dosage form and spiked human plasma. Remarkably, matrix interference was found to be insignificant, underscoring the robustness and applicability of the established approach. The combination of speed, sensitivity, and reproducibility makes this method particularly suitable for assessing medication adherence in patients prescribed AP for hypertension.

9.
J Fluoresc ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39190286

RESUMO

A newly green method for the sensitive quantification of cloperastine, a cough suppressant, in spiked human plasma and its pharmaceutical formulation was designed for the first time. The established method depends on the enhancement of the weak fluorescence of cloperastine using 50 mM sulfuric acid to impair the photoinduced electron transfer produced from the nitrogen atom of piperidine moiety in cloperastine. This full protonation in an acid medium leads to an enhancement in the fluorescence of cloperastine, permitting its linear determination from 0.2 to 5.0 µg/mL with LOD and LOQ of 0.04 and 0.13 µg/mL, respectively. Moreover, the studied drug was estimated in its pharmaceutical market formulations as well as spiked human plasma. Furthermore, the greenness of the described method was evaluated.

10.
Anal Bioanal Chem ; 416(18): 4173-4191, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38795215

RESUMO

A reliable nanotechnological sensing strategy, based on an S,N-co-doped graphene quantum dot (GQD) platform, has been developed to distinctly detect two key variants of vitamin D3, specifically the free (VD3) and the nanoencapsulated form (VD3Ms). For this purpose, food-grade vitamin D3 micelles were self-assembled using a low-energy procedure (droplet size: 49.6 nm, polydispersity index: 0.34, ζ-potential: -33 mV, encapsulation efficiency: 90 %) with an innovative surfactant mixture (Tween 60 and quillaja saponin). Herein, four fluorescent nanoprobes were also synthesized and thoroughly characterized: S,N-co-doped GQDs, α-cyclodextrin-GQDs, ß-cyclodextrin-GQDs, and γ-cyclodextrin-GQDs. The goal was to achieve a selective dual sensing strategy for free VD3 and VD3Ms by exploiting their distinctive quenching behaviors. Thus, the four nanosensors allowed the individual sensing of both targets to be performed (except α-CD-GQD for VD3Ms), but S,N-GQDs were finally selected due to selectivity and sensitivity (quantum yield, QY= 0.76) criteria. This choice led to a photoinduced electron transfer (PET) mechanism associated with static quenching, where differentiation was evidenced through a displayed 13-nm hypsochromic (blue) shift when interacting with VD3Ms. The reliability of this dual approach was demonstrated through an extensive evaluation of analytical performance characteristics. The feasibility and accuracy were proven in commercial food preparations and nutritional supplements containing declared nanoencapsulated and raw VD3, whose results were validated by a paired Student's t-test comparison with a UV-Vis method. To the best of our knowledge, this represents the first non-destructive analytical approach addressing the groundbreaking foodomic trend to distinctly detect different bioactive forms of vitamin D3, while also preserving their native nanostructures as a chemical challenge, thus providing reliable information about their final stability and bioavailability.


Assuntos
Colecalciferol , Análise de Alimentos , Grafite , Micelas , Pontos Quânticos , Pontos Quânticos/química , Grafite/química , Colecalciferol/análise , Análise de Alimentos/métodos , Transporte de Elétrons , Limite de Detecção , Corantes Fluorescentes/química , Espectrometria de Fluorescência/métodos
11.
Luminescence ; 39(9): e4897, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39252443

RESUMO

Monitoring antipsychotic drugs in biological fluids, such as human serum and urine, is important for ensuring the safety and efficacy of psychiatric treatments. This process helps maintain therapeutic drug levels, minimize side effects, and optimize patient well-being. Chlorpromazine (CZ) is a widely prescribed antipsychotic drug used for conditions like schizophrenia, bipolar disorder, and acute psychosis. Almost all existing sensing techniques for CZ are either insensitive spectrophotometric methods or involve long and complex chromatographic procedures, limiting their routine use. In this work, we introduce a facile, green, and sensitive fluorimetric strategy with high reproducibility for detecting CZ in its pure form, tablet formulation, and spiked human plasma and urine without the need for derivatization reactions. The proposed method relies on the inhibition of the intramolecular photoinduced electron transfer (PET) effect by using 2.0 M acetic acid. This approach enables the linear detection of CZ from 3.0 to 600 ng/mL with remarkably low quantitation and detection limits of 1.51 and 0.49 ng/mL, respectively. Moreover, the developed method's greenness was evaluated.


Assuntos
Clorpromazina , Fluorometria , Comprimidos , Clorpromazina/análise , Clorpromazina/sangue , Humanos , Comprimidos/análise , Fluorometria/métodos , Antipsicóticos/sangue , Antipsicóticos/química , Química Verde , Limite de Detecção , Composição de Medicamentos
12.
Luminescence ; 39(6): e4813, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38922756

RESUMO

Pemigatinib (PGT) is a recently FDA-approved small molecule kinase inhibitor used for the treatment of relapsed or refractory myeloid/lymphoid neoplasms in adults. This study introduces the development of a first microwell spectrofluorimetric method (MW-SFM) for quantifying PGT in FDA-approved tablets and plasma samples. The method utilized the enhancement of PGT's weak native fluorescence by blocking photoinduced electron transfer (PET) and micellization with sodium lauryl sulfate (SLS). The MW-SFM was performed in 96-microwell plates, and fluorescence signals were measured using a fluorescence microplate reader with excitation at 290 nm and emission at 350 nm. The method exhibited a linear range of 2-250 ng mL-1, and a limit of quantitation was 6.5 ng mL-1. The accuracy and precision of the method were confirmed with recovery rates ranging from 96.5% to 102.8% and relative standard deviations of 1.52% to 3.51%. The MW-SFM successfully analyzed Pemazyre® tablets, assessed content uniformity, and analyzed PGT-spiked human plasma samples. The greenness of the MW-SFM was verified using three different metric tools. In conclusion, the proposed MW-SFM is a valuable tool in supporting quality assessment of dosage forms, conducting pharmacokinetic studies, and monitoring therapeutic outcomes.


Assuntos
Espectrometria de Fluorescência , Comprimidos , Humanos , Fluorescência , Transporte de Elétrons , Micelas , Pirimidinas/sangue , Pirimidinas/química , Dodecilsulfato de Sódio/química , Estrutura Molecular , Processos Fotoquímicos
13.
Luminescence ; 39(7): e4818, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39004769

RESUMO

Fexofenadine (FEX) is a non-sedating antihistamine commonly used for the treatment of allergic conditions such as seasonal rhinitis and chronic idiopathic urticaria. This study describes the tuning "ON" the intrinsic fluorescence of FEX by switching "OFF" its intramolecular photoinduced electron transfer (PET) through the protonation of the piperidinyl nitrogen atom using sulfuric acid. The resulting fluorescence was utilized as a basis for the development of a highly sensitive microwell spectrofluorimetric assay (MW-SFA) for the one-step determination of FEX in pharmaceutical tablets and plasma. The linear range of the assay was 10-500 ng ml-1, and its limit of quantitation was 25.9 ng ml-1. The proposed MW-SFA was successfully applied to analyze FEX in pharmaceutical tablets and plasma samples, demonstrating good accuracy and precision. The greenness of the assay was confirmed using three metric assessment tools. In conclusion, the MW-SFA is a straightforward, single-step analysis that requires no experimental adjustments. It offers high sensitivity, efficient sample processing, and environmental sustainability. This assay is highly recommended for pharmaceutical quality control and clinical lab use, particularly for measuring FEX levels.


Assuntos
Espectrometria de Fluorescência , Comprimidos , Terfenadina , Terfenadina/análogos & derivados , Terfenadina/sangue , Terfenadina/análise , Terfenadina/química , Transporte de Elétrons , Humanos , Fluorescência , Processos Fotoquímicos , Ensaios de Triagem em Larga Escala , Estrutura Molecular
14.
Angew Chem Int Ed Engl ; 63(6): e202315959, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38063409

RESUMO

Anion sensing via either optical or electrochemical readouts has separately received enormous attention, however, a judicious combination of the advantages of both modalities remains unexplored. Toward this goal, we herein disclose a series of novel, redox-active, fluorescent, halogen bonding (XB) and hydrogen bonding (HB) BODIPY-based anion sensors, wherein the introduction of a ferrocene motif induces remarkable changes in the fluorescence response. Extensive fluorescence anion titration, lifetime and electrochemical studies reveal anion binding-induced emission modulation through intramolecular photoinduced electron transfer (PET), the magnitude of which is dependent on the nature of both the XB/HB donor and anion. Impressively, the XB sensor outperformed its HB congener in terms of anion binding strength and fluorescence switching magnitude, displaying significant fluorescence turn-OFF upon anion binding. In contrast, redox-inactive control receptors display a turn-ON response, highlighting the pronounced impact of the introduction of the redox-active ferrocene on the optical sensing performance. Additionally, the redox-active ferrocene motif also serves as an electrochemical reporter group, enabling voltammetric anion sensing in competitive solvents. The combined advantages of both sensing modalities were further exploited in a novel, proof-of-principle, fluorescence spectroelectrochemical anion sensing approach, enabling simultaneous and sensitive read out of optical and electrochemical responses in multiple oxidation states and at very low receptor concentration.

15.
Angew Chem Int Ed Engl ; 63(39): e202409605, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-38975961

RESUMO

Thioamides are widely used structures in pharmaceuticals and agrochemicals, as well as important synthons for the construction of sulfur-containing heterocycles. This report presents a series of visible-light-driven multicomponent reactions of amines, carbon disulfide, and olefins for the mild and versatile synthesis of linear thioamides and cyclic thiolactams. The use of inexpensive and readily available carbon disulfide as the thiocarbonyl source in a radical pathway enables the facile assembly of structurally diverse amine moieties with non-nucleophilic carbon-based reaction partners. Radical thiocarbamoylative cyclization provides a practical protocol that complements traditional approaches to thiolactams relying on deoxythionation. Mechanistic studies reveal that direct photoexcitation of in situ formed dithiocarbamate anions as well as versatile photoinduced electron transfer with diverse electron acceptors are key to the reactions.

16.
Beilstein J Org Chem ; 20: 125-154, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38292046

RESUMO

Various push-pull chromophores can be synthesized in a single and atom-economical step through [2 + 2] cycloaddition-retroelectrocyclization (CA-RE) reactions involving diverse electron-rich alkynes and electron-deficient alkenes. In this review, a comprehensive investigation of the recent and noteworthy advancements in the research on push-pull chromophores prepared via the [2 + 2] CA-RE reaction is conducted. In particular, an overview of the physicochemical properties of the family of these compounds that have been investigated is provided to clarify their potential for future applications.

17.
Small ; 19(48): e2305024, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37533371

RESUMO

Photocatalytic hydrogen production via water splitting is the subject of intense research. Photoinduced electron transfer (PET) between a photosensitizer (PS) and a proton reduction catalyst is a prerequisite step and crucial to affecting hydrogen production efficiency. Herein, three photoactive metal-organic framework (MOF) systems having two different PET processes where PS and Co(II) centers are either covalently bonded or coexisting to drive photocatalytic H2 production are built. Compared to these two intramolecular PET systems including CoII -Zn-PDTP prepared from the post-synthetic metalation toward uncoordinated pyridine N sites of Zn-PDTP and sole cobalt-based MOF Co-PDTP, the CoII (bpy)3 @Zn-PDTP system impregnated by molecular cocatalyst possessing intermolecular PET process achieves the highest H2 evolution rate of 116.8 mmol g-1 h-1 over a period of 10 h, about 7.5 and 9.3 times compared to CoII -Zn-PDTP and Co-PDTP in visible-light-driven H2 evolution, respectively. Further studies reveal that the enhanced photoactivity in CoII (bpy)3 @Zn-PDTP can be ascribed to the high charge-separation efficiency of Zn-PDTP and the synergistic intermolecular interaction between Zn-PDTP and cobalt complexes. The present work demonstrates that the rational design of PET process between MOFs and catalytic metal sites can be a viable strategy for the development of highly efficient photocatalysts with enhanced photocatalytic activities.

18.
J Fluoresc ; 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37831353

RESUMO

In this work, a facile and fast aqueous-phase synthetic method is proposed to prepare water-soluble ZnS quantum dots stabilized simultaneously with glutathione and L-cysteine (ZnS QDs-GSH/L-Cys). As-synthesized ZnS QDs-GSH/L-Cys were monodispersed spherical nanocrystals with a mean diameter of 5.0 ± 0.7 nm. Besides, the obtained ZnS QDs-GSH/L-Cys emitted more intensive blue fluorescence and exhibited an improved stability in aqueous solution compared with ZnS quantum dots merely stabilized with GSH (ZnS QDs-GSH). Interestingly, Adriamycin, a representative anticancer drug, was added into the solution of ZnS QDs-GSH/L-Cys, the blue fluorescence of ZnS QDs-GSH/L-Cys was greatly enhanced instead of being quenched, which indicated that ZnS QDs-GSH/L-Cys can be used as an enhanced-fluorescence nanoprobe for determining Adriamycin. The observed fluorescent enhancement could be attributed to the blocking of photoinduced electron transfer (PET) in ZnS QDs-GSH/L-Cys due to the electrostatic interaction between the -COO- groups on the surface of quantum dots and the -NH3+ groups in Adriamycin, followed by the coordination interaction among ZnS QDs-GSH/L-Cys and Adriamycin. The fluorescence intensity of ZnS QDs-GSH/L-Cys presented a good linear response with the concentration of Adriamycin ranging from 2.0 to 20 µg•mL-1. The proposed fluorescent nanoprobe exhibited an excellent sensitivity with the LOD of 0.1 µg•mL-1 and a good accuracy for detecting Adriamycin.

19.
J Fluoresc ; 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38095769

RESUMO

A method utilizing nitrogen-doped and sulfur-doped carbon quantum dots (N, S-CQDs) as fluorescent probes for the rapid detection of Fe3+, L-ascorbic acid (AA), and alkaline phosphatase (ALP) was presented. The fluorescence intensity of N, S-CQDs nanoprobes can be rapidly and efficiently quenched by Fe3+ and based on the fluorescence "turn off-on" characteristic of N, S-CQDs nanoprobes, the fluorescence signals of the N, S-CQDs/Fe3+can be recovered after the addition of AA. By coupling a fluorescent nanoprobe to an enzyme and L-ascorbic acid-2-phosphate (AA2P), a green, simple, rapid and effective fluorescent analytical method for the determination of ALP was developed. The prepared N, S-CQDs showed high sensitivity and selectivity to Fe3+, AA and ALP with the detection limit of 0.42 µM, 12.7 nM and 0.017 U·L-1 and their optimal concentration ranges were10-600 µM, 10-200 µM, 0.18-54 U·L-1, respectively. The fluorescence quantum yield of N, S-CQDs (0.2 mg·mL-1) at 393 nm excitation wavelength was 4.41%. Additionally, the fluorescent nanoprobes have been employed to successfully measure ALP in serum samples. It is expected that the established method may offer a new approach for biomolecular detection in clinical diagnosis and pharmaceutical analysis.

20.
J Fluoresc ; 33(2): 471-486, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36445509

RESUMO

Fluorescence spectral techniques aided by molecular docking (Mol.Doc) approach were employed in probing the molecular interactions existing between D-glucose and resorcinol based acridinedione (ADR) dyes. ADR dyes has been classified into PET and non-PET dyes based on the substitution in the 9th position of acridinedione ring structure. Addition of glucose to PET dye (ADR1) resulted in a decrease in the absorbance whereas to that of ADR2 dye (non-PET character in aqueous medium) resulted in a significant increase in the absorbance. The formation of an isosbestic point reveals the existence of a ground state interaction existing between the dye and sugar molecule. Addition of glucose to PET dye resulted in a drastic increase in the fluorescent enhancement (FE) and subsequent addition resulted in a marked decrease in the fluorescent intensity with no apparent shift of emission maximum. Interestingly, neither characteristic shift nor variation in emission intensity was observed in the case of ADR2 dye. Fluorescence lifetime studies of ADR1 dye in the presence of glucose illustrate the existence of multiple distinguishable micro environments of dye. Mol.Doc studies authenticate the co-existence of hydrogen bonding (HB) and hydrophobic interaction wherein the dye and sugar molecule acts as HB donor and acceptor resulting in a stable conformer. These conformers are governed predominantly by HB interactions. The nature of interaction of a simple sugar with ADR dyes are explored in depth by fluorescent techniques in coordination with docking studies is imparted in the present study.


Assuntos
Açúcares , Água , Água/química , Simulação de Acoplamento Molecular , Corantes Fluorescentes/química , Ligação de Hidrogênio , Elétrons , Espectrometria de Fluorescência , Monossacarídeos , Glucose , Hidrogênio
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