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1.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1869(7): 159524, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38857757

RESUMO

Neuroinflammation is a hallmark of several neurodegenerative disorders that has been extensively studied in recent years. Microglia, the primary immune cells of the central nervous system (CNS), are key players in this physiological process, demonstrating a remarkable adaptability in responding to various stimuli in the eye and the brain. Within the complex network of neuroinflammatory signals, the fatty acid N-ethanolamines, in particular N-arachidonylethanolamine (anandamide, AEA), emerged as crucial regulators of microglial activity under both physiological and pathological states. In this study, we interrogated for the first time the impact of the signaling of these bioactive lipids on microglial cell responses to a sub-lethal acute UVB radiation, a physical stressor responsible of microglia reactivity in either the retina or the brain. To this end, we developed an in vitro model using mouse microglial BV-2 cells. Upon 24 h of UVB exposure, BV-2 cells showed elevated oxidative stress markers and, cyclooxygenase (COX-2) expression, enhanced phagocytic and chemotactic activities, along with an altered immune profiling. Notably, UVB exposure led to a selective increase in expression and activity of fatty acid amide hydrolase (FAAH), the main enzyme responsible for degradation of fatty acid ethanolamides. Pharmacological FAAH inhibition via URB597 counteracted the effects of UVB exposure, decreasing tumor necrosis factor α (TNF-α) and nitric oxide (NO) release and reverting reactive oxidative species (ROS), interleukin-1ß (IL-1ß), and interleukin-10 (IL-10) levels to the control levels. Our findings support the potential of enhanced fatty acid amide signaling in mitigating UVB-induced cellular damage, paving the way to further exploration of these lipids in light-induced immune responses.

2.
Mikrochim Acta ; 191(6): 361, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822891

RESUMO

A one-shot CO2 laser-based strategy to generate conductive reduced graphene oxide (rGO) decorated with nanoceria (nCe) is proposed. The 2D/0D rGO-nCe films, integrated as catalytic sensing layers in paper-based sensors, were employed for on-site monitoring of indoor fogging treatments against Listeria monocytogenes (Lm), a ubiquitous pathogenic bacterium. The rGO-nCe laser-assisted synthesis was optimized to preserve the rGO film morphological and electron-transfer features and simultaneously integrate catalytic nCe. The films were characterized by microscopical (SEM), spectroscopical (EDX, Raman, and FTIR), and electrochemical techniques. The most performing film was integrated into a nitrocellulose substrate, and the complete sensor was assembled via a combination of xurography and stencil printing. The rGO-nCe sensor's catalytic activity was proved toward the detection of H2O2, obtaining sensitive determination (LOD = 0.3 µM) and an extended linear range (0.5-1500 µM). Eventually, the rGO-nCe sensor was challenged for the real-time continuous monitoring of hydrogen peroxide aerosol during no-touch fogging treatment conducted following the EU's recommendation for biocidal product use. Treatment effectiveness was proved toward three Lm strains characterized by different origins, i.e., type strain ATCC 7644, clinical strain 338, and food strain 641/6II. The sensor allows for discrimination and quantification treatments at different environmental biocidal amounts and fogging times, and correlates with the microbiological inhibition, promoting the proposed sensor as a useful tool to modulate and monitor no-touch treatments.


Assuntos
Desinfecção , Grafite , Peróxido de Hidrogênio , Lasers , Listeria monocytogenes , Papel , Grafite/química , Peróxido de Hidrogênio/química , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/isolamento & purificação , Desinfecção/métodos , Cério/química , Limite de Detecção , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Catálise
3.
ACS Appl Mater Interfaces ; 16(17): 22443-22454, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38629300

RESUMO

Herein, a strategy to stamp laser-produced reduced graphene oxide (rGO) onto flexible polymers using only office-grade tools, namely, roll-to-roll thermal stamping, is proposed, proving for the first time its effectiveness for direct bioelectrocatalysis. This straightforward, scalable, and low-cost approach allows us to overcome the limits of the integration of laser-induced rGO-films in bioanalytical devices. Laser-produced rGO has been thermally stamped (TS) onto different polymeric substrates (PET, PVC, and EVA) using a simple roll-laminator; the obtained TS-rGO films have been compared with the native rGO (untransferred) via morphochemical and electrochemical characterization. Particularly, the direct electron transfer (DET) reaction between fructose dehydrogenase (FDH) and TS-rGO transducers has been investigated, with respect to the influence of the amount of enzyme on the catalytic process. Remarkable differences have been observed among TS-rGO transducers; PET proved to be the elective substrate to support the transfer of the laser-induced rGO, allowing the preservation of the morphochemical features of the native material and returning a reduced capacitive current. Noteworthily, TS-rGOs ensure superior electrocatalysis using a very low amount of FDH units (15 mU). Eventually, TS-rGO-based third-generation complete enzymatic biosensors were fabricated via low-cost benchtop technologies. TS-rGOPET exhibited bioanalytical performances superior to the native rGO, allowing a sensitive (0.0289 µA cm-2 µM-1) and reproducible (RSD = 3%, n = 3) d-fructose determination at the nanomolar level (LOD = 0.2 µM). TS-rGO exploitability as a point-of-need device was proved via the monitoring of d-fructose during banana (Musa acuminata) postharvest ripening, returning accurate (recoveries 110-90%; relative error -13/+1%) and reproducible (RSD ≤ 7%; n = 3) data.


Assuntos
Grafite , Lasers , Grafite/química , Transporte de Elétrons , Técnicas Eletroquímicas , Desidrogenases de Carboidrato/química , Desidrogenases de Carboidrato/metabolismo , Técnicas Biossensoriais , Oxirredução
4.
Transl Psychiatry ; 14(1): 118, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409080

RESUMO

Obsessive Compulsive Disorder (OCD) is listed as one of the top 10 most disabling neuropsychiatric conditions in the world. The neurobiology of OCD has not been completely understood and efforts are needed in order to develop new treatments. Beside the classical neurotransmitter systems and signalling pathways implicated in OCD, the possible involvement of the endocannabinoid system (ECS) has emerged in pathophysiology of OCD. We report here selective downregulation of the genes coding for enzymes allowing the synthesis of the endocannabinoids. We found reduced DAGLα and NAPE-PLD in blood samples of individuals with OCD (when compared to healthy controls) as well as in the amygdala complex and prefrontal cortex of dopamine transporter (DAT) heterozygous rats, manifesting compulsive behaviours. Also mRNA levels of the genes coding for cannabinoid receptors type 1 and type 2 resulted downregulated, respectively in the rat amygdala and in human blood. Moreover, NAPE-PLD changes in gene expression resulted to be associated with an increase in DNA methylation at gene promoter, and the modulation of this gene in OCD appears to be correlated to the progression of the disease. Finally, the alterations observed in ECS genes expression appears to be correlated with the modulation in oxytocin receptor gene expression, consistently with what recently reported. Overall, we confirm here a role for ECS in OCD at both preclinical and clinical level. Many potential biomarkers are suggested among its components, in particular NAPE-PLD, that might be of help for a prompt and clear diagnosis.


Assuntos
Endocanabinoides , Transtorno Obsessivo-Compulsivo , Humanos , Ratos , Animais , Endocanabinoides/genética , Tonsila do Cerebelo/metabolismo , Córtex Pré-Frontal/metabolismo , Metilação de DNA
5.
Chemosphere ; 342: 140167, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37717917

RESUMO

Among emerging layered materials, 2D transition metal dichalcogenides (TMDs) nanosheets (n-sheets) have received increasing attention for optoelectronics, energy storage, and, recently, for bioremediation and advanced biomedical applications; however, a lack of ecotoxicological in vivo studies is evident. Herein, for the first time, the potential nanotoxicity of liquid phase exfoliated Group VI TMDs n-sheets (MoS2, WS2, WSe2, and MoSe2) was comparatively investigated using zebrafish embryos (Z-EBs) as an in-vivo model. The 2D n-sheets were produced directly in aqueous-medium, the obtained n-sheets were characterized by scanning electron microscopy, Raman and visible spectroscopy, and their potential nanotoxicity was investigated by fish embryo test OECD TG 236. Chorionated and dechorionated embryos were used to assess the severity of TMD exposure. The survival rate, sublethal alteration during embryogenesis, hatching rate, and mortality were evaluated. TMDs n-sheets tend to adhere to the Z-EBs surface depending on their chemistry. Despite this, TMDs did not show lethal effects; weak sublethal effects were found for MoS2 and WSe2, while slight hatching delays were registered for MoSe2 and WSe2. The observed effects are attributable to the TMDs' tendency to interact with Z-EBs, because of the different chemistry. This work demonstrates how water-dispersed TMDs are potential eco/biocompatible materials.


Assuntos
Molibdênio , Peixe-Zebra , Animais , Molibdênio/toxicidade , Materiais Biocompatíveis , Ecotoxicologia , Metais
6.
Mikrochim Acta ; 190(8): 306, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37466678

RESUMO

An electrochemical impedimetric biosensor for human serum albumin (HSA) determination is proposed. The biosensor is based on water-phase assembled nanocomposites made of 2D WS2 nanoflakes and Au nanoparticles (AuNPs). The WS2 has been produced using a liquid-phase exfoliation strategy assisted by sodium cholate, obtaining a water-stable suspension that allowed the straightforward decoration with AuNPs directly in the aqueous phase. The resulting WS2/Au nanocomposite has been characterized by atomic force microscopy and Raman spectroscopy and, then, employed to modify screen-printed electrodes. Good electron-transfer features have been achieved. An electrochemical immunosensing platform has been assembled exploiting cysteamine-glutaraldehyde covalent chemistry for antibody (Ab) immobilization. The resulting immunosensor exhibited good sensitivity for HSA detection (LOD = 2 ng mL-1), with extended linear range (0.005 - 100 µg mL-1), providing a useful analytical tool for HSA determination in urine at relevant clinical ranges for microalbuminuria screening. The HSA quantification in human urine samples resulted in recoveries from 91.8 to 112.4% and was also reproducible (RSD < 7.5%, n = 3), with marked selectivity. This nanocomposite, thanks to the reliable performance and the ease of the assembling strategy, is a promising alternative for electrochemical immunosensing of health relevant markers.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Nanocompostos , Humanos , Nanopartículas Metálicas/química , Água , Ouro/química , Técnicas Biossensoriais/métodos , Imunoensaio/métodos , Albumina Sérica Humana , Nanocompostos/química
7.
Biosens Bioelectron ; 237: 115450, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37343312

RESUMO

Herein, we report a scalable benchtop electrode fabrication method to produce highly sensitive and flexible third-generation fructose dehydrogenase amperometric biosensors based on water-dispersed 0D-nanomaterials. The electrochemical platform was fabricated via Stencil-Printing (StPE) and insulated via xurography. Carbon black (CB) and mesoporous carbon (MS) were employed as 0D-nanomaterials promoting an efficient direct electron transfer (DET) between fructose dehydrogenase (FDH) and the transducer. Both nanomaterials were prepared in water-phase via a sonochemical approach. The nano-StPE exhibited enhanced electrocatalytic currents compared to conventional commercial electrodes. The enzymatic sensors were exploited for the determination of D-fructose in model solutions and various food and biological samples. StPE-CB and StPE-MS integrated biosensors showed appreciable sensitivity (∼150 µA cm-2 mM-1) with µmolar limit of detection (0.35 and 0.16 µM, respectively) and extended linear range (2-500 and 1-250 µM, respectively); the selectivity of the biosensors, ensured by the low working overpotential (+0.15 V), has been also demonstrated. Good accuracy (recoveries between 95 and 116%) and reproducibility (RSD ≤8.6%) were achieved for food and urine samples. The proposed approach because of manufacturing versatility and the electro-catalytic features of the water-nanostructured 0D-NMs opens new paths for affordable and customizable FDH-based bioelectronics.


Assuntos
Técnicas Biossensoriais , Frutose , Reprodutibilidade dos Testes , Técnicas Biossensoriais/métodos , Eletrodos , Oxirredutases , Água
8.
Nanoscale ; 15(15): 7164-7175, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37009987

RESUMO

The production of 2D/2D heterostructures (HTs) with favorable electrochemical features is challenging, particularly for semiconductor transition metal dichalcogenides (TMDs). In this studies, we introduce a CO2 laser plotter-based technology for the realization of HT films comprising reduced graphene oxide (rGO) and 2D-TMDs (MoS2, WS2, MoSe2, and WSe2) produced via water phase exfoliation. The strategy relies on the Laser-Induced production of HeterosTructures (LIHTs), where after irradiation the nanomaterials exhibit changes in the morphological and chemical structure, becoming conductive easily transferable nanostructured films. The LIHTs were characterized in detail by SEM, XPS, Raman and electrochemical analysis. The laser treatment induces the conversion of GO into conductive highly exfoliated rGO decorated with homogeneously distributed small TMD/TM-oxide nanoflakes. The freestanding LIHT films obtained were employed to build self-contained sensors onto nitrocellulose, where the HT works both as a transducer and sensing surface. The proposed nitrocellulose-sensor manufacturing process is semi-automated and reproducible, multiple HT films may be produced in the same laser treatment and the stencil-printing allows customizable design. Excellent performance in the electroanalytical detection of different molecules such as dopamine (a neurotransmitter), catechin (a flavonol), and hydrogen peroxide was demonstrated, obtaining nanomolar limits of detection and satisfactory recovery rates in biological and agrifood samples, together with high fouling resistance. Considering the robust and rapid laser-induced production of HTs and the versatility of scribing desired patterns, the proposed approach appears as a disruptive technology for the development of electrochemical devices through sustainable and accessible strategies.

9.
Food Chem ; 420: 136112, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37059022

RESUMO

An electroanalytical lab-on-a-strip device for the direct extra-virgin olive oil (EVOO) antioxidant capacity evaluation is proposed. The lab-made device is composed of a CO2 laser nanodecorated sensor combined with a cutter-plotter molded paper-strip designed for EVOOs sampling and extraction. Satisfactory performance towards the most representative o-diphenols of EVOOs i.e., hydroxytyrosol (HY) and oleuropein (OL) were achieved; good sensitivity (LODHY = 2 µM; LODOL = 0.6 µM), extended linear ranges (HY: 10-250 µM; OL: 2.5-50 µM) and outstanding reproducibility (RSD < 5%, n = 3) were obtained in rectified oil. The device was challenged for the extraction-free analysis of 15 different EVOO samples, with satisfactory recoveries (90-94%; RSD < 5%, n = 3) and correlation with classical photometric assays (r ≥ 0.91). The proposed device includes all analysis steps, needs 4 µL of sample, and returns reliable results in 2 min, resulting portable and usable with a smartphone.


Assuntos
Antioxidantes , Lasers , Azeite de Oliva/análise , Antioxidantes/análise , Reprodutibilidade dos Testes
10.
Anal Methods ; 15(10): 1250-1253, 2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36861684

RESUMO

The development of ultrasensitive analytical detection methods for organophosphorus pesticides such as dimethoate (DMT) plays a key role in healthy food production. DMT is an inhibitor of acetylcholinesterase (AChE), which can lead to the accumulation of acetylcholine and result in symptoms related to the autonomous and central nervous systems. Herein, we report the first spectroscopic and electrochemical study on template removal after an imprinting process from a polypyrrole-based molecularly imprinted polymer (PPy-MIP) film for the detection of DMT. Several template removal procedures were tested and evaluated using X-ray photoelectron spectroscopy. The most effective procedure was achieved in 100 mM NaOH. The proposed DMT PPy-MIP sensor exhibits a limit of detection of (8 ± 2) × 10-12 M.


Assuntos
Impressão Molecular , Praguicidas , Polímeros/química , Dimetoato , Pirróis/química , Impressão Molecular/métodos , Acetilcolinesterase , Compostos Organofosforados
11.
Foods ; 12(6)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36981218

RESUMO

The transition to a sustainable economic and environmental management of olive oil sector needs to be implemented in both national and regional territories through the introduction and development of innovative growing systems and variety. In this study, the olive oil quality parameters of local and allochthonous varieties cultivated in different orchards located in the Abruzzo region (Italy), using traditional and super high-density systems, were analyzed. Frantene, Lecciana, Koroneiki, and a mix of Arbequina and Lecciana provided olive oils rich in flavonoids and secoiridoids compounds with respect to the local varieties Frantoio, Leccino, and a mix of Dritta, Leccino, and Pendolino. Oleic/linoleic ratio was influenced by cultivar and training systems with super high-density olive oils rich in oleic acid. Frantene showed a peculiar fatty acid profile different from cultivars grown in the same location; moreover, interesting similarities were found between Frantene and the mix of Dritta, Leccino, and Pendolino in terms of health-related compounds. The potential development of innovative sustainable training system to improve olive oil quality was highlighted. The study's results identify olive varieties suitable for super high-density systems spread in the Abruzzo region, representing a valid alternative for the olive growers to improve both the quality of the olive oil, as well as the company's income.

12.
Int J Mol Sci ; 24(5)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36902221

RESUMO

Nowadays, the adoption of In Vitro Fertilization (IVF) techniques is undergoing an impressive increase. In light of this, one of the most promising strategies is the novel use of non-physiological materials and naturally derived compounds for advanced sperm preparation methods. Here, sperm cells were exposed during capacitation to MoS2/Catechin nanoflakes and catechin (CT), a flavonoid with antioxidant properties, at concentrations of 10, 1, 0.1 ppm. The results showed no significant differences in terms of sperm membrane modifications or biochemical pathways among the groups, allowing the hypothesis that MoS2/CT nanoflakes do not induce any negative effect on the parameters evaluated related to sperm capacitation. Moreover, the addition of CT alone at a specific concentration (0.1 ppm) increased the spermatozoa fertilizing ability in an IVF assay by increasing the number of fertilized oocytes with respect to the control group. Our findings open interesting new perspectives regarding the use of catechins and new materials obtained using natural or bio compounds, which could be used to implement the current strategies for sperm capacitation.


Assuntos
Catequina , Masculino , Suínos , Animais , Catequina/farmacologia , Molibdênio/metabolismo , Sêmen , Fertilização , Espermatozoides/metabolismo , Fertilização in vitro
13.
Talanta ; 257: 124392, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36863295

RESUMO

The present study encompasses the development of a fast and reliable analytical method to quantify the main endocannabinoids and some of their conjugated congeners, particularly N-arachidonoyl amino acids, in brain tissue. Samples were homogenized and a micro solid phase extraction (µSPE) procedure was developed for brain homogenate clean-up. Miniaturized SPE was selected as it allowed to work with reduced sample amounts, while maintaining high sensitivity; this last feature was mandatory due to the low concentration of endocannabinoids in biological matrices that makes their determination a challenging analytical task. UHPLC-MS/MS was used for the analysis as it provided a great sensitivity, especially for conjugated forms that were detected by negative ionization. Polarity switching was applied during the run; low limits of quantification were between 0.003 ng g-1 and 0.5 ng g-1. This method provided also low matrix effect (lower than 30%) and good extraction recoveries in the brain. To the best of our knowledge, this is the first time that µSPE is applied on this matrix for this class of compounds. The method was validated according to international guidelines, and then tested on real cerebellum samples from mice, which were sub-chronically treated with URB597, a well-known inhibitor of the fatty acid amide hydrolase.


Assuntos
Endocanabinoides , Espectrometria de Massas em Tandem , Animais , Camundongos , Cromatografia Líquida de Alta Pressão/métodos , Endocanabinoides/química , Espectrometria de Massas em Tandem/métodos , Extração em Fase Sólida/métodos , Encéfalo
14.
ACS Sens ; 8(2): 598-609, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36734274

RESUMO

The combination of two-dimensional materials and metal nanoparticles (MNPs) allows the fabrication of novel nanocomposites with unique physical/chemical properties exploitable in high-performance smart devices and biosensing strategies. Current methods to obtain graphene-based films decorated with noble MNPs are cumbersome, poorly reproducible, and difficult to scale up. Herein, we propose a straightforward, versatile, surfactant-free, and single-step technique to produce reduced graphene oxide (rGO) conductive films integrating "naked" noble MNPs. This method relies on the instantaneous laser-induced co-reduction of graphene oxide and metal cations, resulting in highly exfoliated rGO nanosheets embedding gold, silver, and platinum NPs. The production procedure has been optimized, and the obtained nanomaterials are fully characterized; the hybrid nanosheets have been easily transferred onto lab-made screen-printed electrodes preserving their nanoarchitecture. The Au@rGO-, Ag@rGO-, and Pt@rGO-based electrodes have been challenged to detect caffeic acid, nitrite, and hydrogen peroxide in model solutions and real samples. The sensors yielded quantitative responses (R2 ≥ 0.997) with sub-micromolar limits of detections (LODs ≤ 0.6 µM) for all the analytes, allowing accurate quantification in samples (recoveries ≥ 90%; RSD ≤ 14.8%, n = 3). This single-step protocol which requires low cost and minimal equipment will allow the fabrication of free-standing, MNP-embedded rGO films integrable into a variety of scalable smart devices and biosensors.


Assuntos
Grafite , Nanopartículas Metálicas , Grafite/química , Técnicas Eletroquímicas/métodos , Nanopartículas Metálicas/química , Ouro/química
15.
Molecules ; 28(4)2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36838519

RESUMO

Lupin alkaloids (LAs) represent a class of toxic secondary metabolites in plants, in particular in Lupinus spp.; they are produced as a defense mechanism due to their strong bitter taste and are very dangerous for human and animals. In this work, a sensitive and reliable high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) analytical method for the identification and quantification of thirteen lupin alkaloids was developed and validated according to FDA guidelines. Efficient extraction and clean-up steps, carried out by solid-phase extraction, were finely tuned on the basis of the characteristics of the analytes and lupin samples, providing good selectivity with minimized matrix interference. The effectiveness of the method was proven by the satisfactory recovery values obtained for most of the analytes and a matrix effect ≤23% for all tested levels. In addition, a sensitive and reliable determination of the target compounds was obtained; LOQs were between 1 and 25 µg Kg-1, i.e., below the requested maximum levels (<200 mg Kg-1). The method was applied to evaluate the LAs profile in different batches of raw L. albus L. samples, varying in size and across farming treatments.


Assuntos
Alcaloides , Lupinus , Animais , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Lupinus/química , Alcaloides/química , Extração em Fase Sólida
16.
Nanomaterials (Basel) ; 13(3)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36770338

RESUMO

The demand for next-generation multifunctional nanovectors, combining therapeutic effects with specific cellular targeting, has significantly grown during the last few years, pursuing less invasive therapy strategies. Polyphenol-conjugated silver nanoparticles (AgNPs) appear as potential multifunctional nanovectors, integrating the biorecognition capability and the antioxidant power of polyphenols, the antimicrobial activity of silver, and the drug delivery capability of NPs. We present a spectroscopic and microscopic investigation on polyphenol-synthesized AgNPs, selecting caffeic acid (CA) and catechol (CT) as model polyphenols and using them as reducing agents for the AgNP green synthesis, both in the presence and in the absence of a capping agent. We exploit the plasmonic properties of AgNPs to collect Surface-Enhanced Raman Scattering (SERS) spectra from the nanosized region next to the Ag surface and to characterize the molecular environment in the proximity of the NP, assessing the orientation and tunable deprotonation level of CA, depending on the synthesis conditions. Our results suggest that the SERS investigation of such nanovectors can provide crucial information for their perspective biomedical application.

17.
Molecules ; 28(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36677761

RESUMO

Aflatoxins (AFs) are fungi secondary metabolites produced by the Aspergillus family. These compounds can enter the food chain through food contamination, representing a risk to human health. Commercial immunoaffinity columns are widely used for the extraction and cleanup of AFs from food samples; however, their high cost and large solvent consumption create a need for alternative strategies. In this work, an alternative strategy for producing molecularly imprinted polymers (MIPs) was proposed to extract aflatoxins AFB1, AFB2, AFG1, and AFG2 from complex food samples, using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The MIPs were synthesized via a low-cost and rapid (5 min) sonochemical free-radical polymerization, using 1-hydroxy-2-naphthoic acid as a dummy template. MIPs-based solid phase extraction performance was tested on 17 dietary supplements (vegetables, fruits, and cereals), obtaining appreciable recovery rates (65-90%) and good reproducibility (RSD ≤ 6%, n = 3); the selectivity towards other mycotoxins was proved and the data obtained compared with commercial immunoaffinity columns. The proposed strategy can be considered an alternative affordable approach to the classical immunoaffinity columns, since it is more selective and better performing.


Assuntos
Aflatoxinas , Contaminação de Alimentos , Aflatoxinas/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Contaminação de Alimentos/análise , Polímeros Molecularmente Impressos/análise , Reprodutibilidade dos Testes , Extração em Fase Sólida , Espectrometria de Massas em Tandem/métodos
18.
Chemosphere ; 317: 137884, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36657583

RESUMO

Industrial wastes have become elective sustainable sources to obtain materials for electronic/electroanalytical purposes; on the other hand, easy and green strategies to include semiconductor 2D graphene-like materials in conductive networks are highly required. In this work, 1D/2D nanocomposites (NCs) based on nanofibrillar biochar (BH) from paper industry waste and transition metal dichalcogenides (TMDs: MoS2, WS2, MoSe2, and WSe2), were prepared in water via liquid phase exfoliation (LPE) using sodium cholate as bioderived surfactant. The TMD amount in the NCs has been carefully optimized, searching for the best compromise between electron transfer ability and electroanalytical performances. Four different water-dispersed BH-TMD NCs have been selected and comprehensively studied from the electrochemical point of view and morphologically characterized. The BH-TMDs potentiality have been demonstrated in model solutions and real samples towards different analytes of biological and agri-food interest. The most performing NCs have been selected and used for the simultaneous determination of the neurotransmitters dopamine (DP) and serotonin (SR), and the flavonoids quercetin (QR) and rutin (RT), obtaining good linearity (R2 ≥ 0.9956) with limits of detection ranging from 10 to 200 nM. Reproducible quantitative recovery values (90-112%, RSD ≤6%, n = 3) were obtained analyzing simultaneously DP and SR in synthetic biological fluid and drugs, and QR and RT in food supplements, proving the usability of the proposed materials for real analyses. This work proves that BH-nanofibers act as a sustainable conductive hosting network for 2D-TMDs, allowing full exploit their electroanalytical potential. The proposed BH-TMD NCs represent a sustainable, affordable, and captivating opportunity for the electrochemical and (bio)sensoristic field.


Assuntos
Resíduos Industriais , Nanocompostos , Suplementos Nutricionais , Dopamina
19.
Nat Prod Res ; 37(15): 2591-2595, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35289674

RESUMO

In this work, the chemical composition and the antioxidant evaluation of the inflorescences from 12 Cannabis sativa L. monoecious cultivars (Carmagnola Lemon CL, Ferimon F, Gran Sasso Kush GSK, Antal A, Carmagnola C, Kompolti K, Futura 75 F75, Villanova V, Tiborzallasi T, Finola FL, Kc Virtus KV and Pineapple P) cultivated at the same condition, were investigated. GC-MS analysis was carried out to evaluate the volatile fraction, while HPLC-MS/MS was used for cannabinoids and polyphenolic compounds. The evaluation of antioxidant activity was carried out using ABTS*+, Trolox equivalence antioxidant capacity (TEAC), ferric reducing antioxidant property (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH*) assays in vitro. The obtained data, demonstrated that each cultivar has a characteristic chemical profile, with highest antioxidant capacity for CL, F75, GSK and F. Based on the in vitro antioxidant activity the plant extracts can be considered as promising candidates for different applications in food field.


Assuntos
Canabinoides , Cannabis , Cannabis/química , Antioxidantes/análise , Espectrometria de Massas em Tandem , Canabinoides/química , Extratos Vegetais/análise
20.
Anal Chim Acta ; 1237: 340594, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36442936

RESUMO

Noble metal nanoparticles (MNPs), have represented the keystone of a plethora of (bio)sensing analytical strategies because of their unique physicochemical features, becoming unique tools in the analytical scenario; in particular, MNPs localized surface plasmon resonance (LSPR) offers infinite analytical possibilities. In this work, the scaling-up from colloidal MNPs to their integration in solid substrates is overviewed, and the relative sensing and biosensing optical strategies based on LSPR changes are systematically treated in accordance with the supporting substrate employed. Recent literature and key papers reporting MNPs integration into solid substrates are considered, paying particular attention to the MNPs-based event into/onto the solid support and the related plasmonic change used as analytical signal. The review is organized in sections according to the solid support nature (glass, polymers, cellulose) and the papers are discussed according to the sensing strategy. The strategies have been classified in MNPs synthesis, growth, etching, displacement/aggregation directly or indirectly mediated by the analyte(s); only works that rely on plasmonic-transduction principles are taken into account, MNPs used as catalysts or in lateral flow systems are not considered. The review demonstrates that MNPs decorated/integrated substrates are now mature analytical tools, able to overcome the limitations of MNPs colloidal suspensions; this results in new analytical opportunities, particularly the realization of integrated systems, lab-on-chip/lab-on-strip and flexible devices, paving the way for a new generation of plasmonic (bio)sensors for point-of-need applications.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Ressonância de Plasmônio de Superfície , Celulose , Polímeros
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