Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.356
Filtrar
Más filtros

Intervalo de año de publicación
1.
Annu Rev Neurosci ; 42: 271-293, 2019 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-30939100

RESUMEN

Magnetic fields pass through tissue undiminished and without producing harmful effects, motivating their use as a wireless, minimally invasive means to control neural activity. Here, we review mechanisms and techniques coupling magnetic fields to changes in electrochemical potentials across neuronal membranes. Biological magnetoreception, although incompletely understood, is discussed as a potential source of inspiration. The emergence of magnetic properties in materials is reviewed to clarify the distinction between biomolecules containing transition metals and ferrite nanoparticles that exhibit significant net moments. We describe recent developments in the use of magnetic nanomaterials as transducers converting magnetic stimuli to forms readily perceived by neurons and discuss opportunities for multiplexed and bidirectional control as well as the challenges posed by delivery to the brain. The variety of magnetic field conditions and mechanisms by which they can be coupled to neuronal signaling cascades highlights the desirability of continued interchange between magnetism physics and neurobiology.


Asunto(s)
Conducta Animal/fisiología , Encéfalo/fisiología , Campos Magnéticos , Red Nerviosa/fisiología , Animales , Ansiedad/fisiopatología , Humanos , Neuronas/fisiología
2.
Nano Lett ; 24(17): 5093-5103, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38578845

RESUMEN

Recent advances in single-particle photothermal circular dichroism (PT CD) and photothermal magnetic circular dichroism (PT MCD) microscopy have shown strong promise for diverse applications in chirality and magnetism. Photothermal circular dichroism microscopy measures direct differential absorption of left- and right-circularly polarized light by a chiral nanoobject and thus can measure a pure circular dichroism signal, which is free from the contribution of circular birefringence and linear dichroism. Photothermal magnetic circular dichroism, which is based on the polar magneto-optical Kerr effect, can probe the magnetic properties of a single nanoparticle (of sizes down to 20 nm) optically. Single-particle measurements enable studies of the spatiotemporal heterogeneity of magnetism at the nanoscale. Both PT CD and PT MCD have already found applications in chiral plasmonics and magnetic nanomaterials. Most importantly, the advent of these microscopic techniques opens possibilities for many novel applications in biology and nanomaterial science.

3.
Nano Lett ; 24(1): 270-278, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38157214

RESUMEN

Here, we introduce the magneto-mechanical-genetic (MMG)-driven wireless deep brain stimulation (DBS) using magnetic nanostructures for therapeutic benefits in the mouse model of Parkinson's disease (PD). Electrical DBS of the subthalamic nucleus (STN) is an effective therapy for mitigating Parkinson's motor symptoms. However, its broader application is hampered by the requirement for implanted electrodes and the lack of anatomical and cellular specificity. Using the nanoscale magnetic force actuators (m-Torquer), which deliver torque force under rotating magnetic fields to activate pre-encoded Piezo1 ion channels on target neurons, our system enables wireless and STN-specific DBS without implants, addressing key unmet challenges in the DBS field. In both late- and early-stage PD mice, MMG-DBS significantly improved locomotor activity and motor balance by 2-fold compared to untreated PD mice. Moreover, MMG-DBS enabled sustained therapeutic effects. This approach provides a non-invasive and implant-free DBS with cellular targeting capability for the effective treatment of Parkinsonian symptoms.


Asunto(s)
Estimulación Encefálica Profunda , Enfermedad de Parkinson , Trastornos Parkinsonianos , Núcleo Subtalámico , Ratones , Animales , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/terapia , Trastornos Parkinsonianos/terapia , Núcleo Subtalámico/fisiología , Neuronas/fisiología , Canales Iónicos
4.
Biochem Biophys Res Commun ; 734: 150464, 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39083970

RESUMEN

Breast cancer is most common cancer among women in the World. Thymoquinone (TQ) exhibits a wide range of biological activities such as anticancer, antidiabetic, antimicrobial, analgesic, antioxidant, and anti-inflammatory effects. However, its effectiveness in cancer treatment is hindered by its poor bioavailability, attributed to its limited solubility in water. Hence, novel strategies are required to enhance the bioavailability of TQ, which possesses remarkable anticancer characteristics. The aim of this study is to prepare pHEMA-based magnetic nanoparticles carrying TQ (TQ-MNPs) to improve bioavailability, and therapeutic efficacy against breast cancer. For this purpose, TQ-MNPs were synthesized and characterized with Fourier transform infrared spectrophotometer (FTIR), scanning electron microscopy (SEM), dynamic light scattering (DLS), magnetic field using a vibrating sample magnetometer (VSM). The loading capabilities of synthesized magentic nanostructures were evaluated, and release investigations were conducted under experimental conditions that mimic the cellular environment. The findings of the studies indicated that the TQ carrying capacity of MNPs was deemed satisfactory, and the release efficiency was adequate. MNPs and TQ-MNPs showed biocompatibility against HDFa cells. TQ-MNPs showed stronger anti-proliferative activity against MCF-7 breast cancer cells compared to free TQ (p < 0.05). TQ-MNPs induced apoptosis in MCF-7 breast cancer cells.

5.
Small ; 20(4): e2304527, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37715071

RESUMEN

Magnetic nanoparticles (NPs) are widely employed for remote controlled molecular release applications using alternating magnetic fields (AMF). Yet, they intrinsically generate heat in the process by Néel relaxation limiting their application scope. In contrast, iron oxide NPs larger than ≈15 nm react to AMF by Brownian relaxation resulting in tumbling and shaking. Here, such iron oxide NPs are combined with polymer shells where the shaking motion mechanically agitates and partially detaches the polymer chains, covalently cleaves a fraction of the polymers, and releases the prototypical cargo molecules doxorubicin and curcumin into solution. This heat-free release mechanism broadens the potential application space of polymer-functionalized magnetic NP composites.

6.
Small ; 20(30): e2312220, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38344893

RESUMEN

Enzymatic activity depends on and can therefore be regulated by temperature. Selective modulation of the activity of different enzymes in one reaction pot would require temperature control local to each type of enzyme. It has been suggested previously that immobilization of enzyme on magnetic nanoparticles and exposing them to alternating magnetic field can enhance the reaction rate. This enhancement has been explained as being mediated by temperature increase caused by dissipation of the absorbed field energy in the form of heat. However, the possibility of spatially limiting this temperature increase on the microscale has been questioned. Here, it is investigated whether an activity enhancement of the enzyme sucrose phosphorylase immobilized on magnetic beads can be achieved, how this effect is related to the increase in temperature, and whether temperature differences within one reaction pot could be generated in this way. It is found that alternating magnetic field stimulation leads to increased enzymatic activity fully attributable to the increase of bulk temperature. Both theoretical analysis and experimental data indicate that no local heating near the particle surface takes place. It is further concluded that relevant increase of surface temperature can be obtained only with macroscopic, millimeter-sized, magnetic particles.


Asunto(s)
Activación Enzimática , Temperatura , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Campos Magnéticos , Glucosiltransferasas/metabolismo
7.
Small ; 20(5): e2304848, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37732364

RESUMEN

Nowadays, magnetic nanoparticles (MNPs) are applied in numerous fields, especially in biomedical applications. Since biofluidic samples and biological tissues are nonmagnetic, negligible background signals can interfere with the magnetic signals from MNPs in magnetic biosensing and imaging applications. In addition, the MNPs can be remotely controlled by magnetic fields, which make it possible for magnetic separation and targeted drug delivery. Furthermore, due to the unique dynamic magnetizations of MNPs when subjected to alternating magnetic fields, MNPs are also proposed as a key tool in cancer treatment, an example is magnetic hyperthermia therapy. Due to their distinct surface chemistry, good biocompatibility, and inducible magnetic moments, the material and morphological structure design of MNPs has attracted enormous interest from a variety of scientific domains. Herein, a thorough review of the chemical synthesis strategies of MNPs, the methodologies to modify the MNPs surface for better biocompatibility, the physicochemical characterization techniques for MNPs, as well as some representative applications of MNPs in disease diagnosis and treatment are provided. Further portions of the review go into the diagnostic and therapeutic uses of composite MNPs with core/shell structures as well as a deeper analysis of MNP properties to learn about potential biomedical applications.


Asunto(s)
Hipertermia Inducida , Nanopartículas de Magnetita , Nanopartículas de Magnetita/uso terapéutico , Nanopartículas de Magnetita/química , Sistemas de Liberación de Medicamentos/métodos , Magnetismo/métodos , Hipertermia Inducida/métodos , Campos Magnéticos
8.
Biomed Microdevices ; 26(1): 13, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38270676

RESUMEN

Nanostructured materials have gained significant attention in recent years for their potential in biological applications, such as cell and biomolecular sorting, as well as early detection of metastatic cancer. Among these materials, magnetic nanoparticles (MNPs) stand out for their easy functionalization, high specific surface area, chemical stability, and superparamagnetic properties. However, conventional fabrication methods can lead to inconsistencies in MNPs' characteristics and performance, highlighting the need for a cost-effective, controllable, and reproducible synthesis approach. In this review, we will discuss the utilization of microfluidic technology as a cutting-edge strategy for the continuous and regulated synthesis of MNPs. This approach has proven effective in producing MNPs with a superior biomedical performance by offering precise control over particle size, shape, and surface properties. We will examine the latest research findings on developing and integrating MNPs synthesized through continuous microfluidic processes for a wide range of biological applications. By providing an overview of the current state of the field, this review aims to showcase the advantages of microfluidics in the fabrication and integration of MNPs, emphasizing their potential to revolutionize diagnostic and therapeutic methods within the realm of biotechnology.


Asunto(s)
Nanopartículas de Magnetita , Microfluídica , Movimiento Celular , Tamaño de la Partícula , Propiedades de Superficie
9.
Chemphyschem ; : e202400023, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39046870

RESUMEN

Iron oxide nanoflowers (IONFs) that display singular magnetic properties can be synthesized through a polyol route first introduced almost 2 decades ago by Caruntu et al, presenting a multi-core morphology in which several grains (around 10 nm) are attached together and sintered. These outstanding properties are of great interest for magnetic field hyperthermia, which is considered as a promising therapy against cancer. Although of significantly smaller diameter, the specific adsorption rate (SAR) of IONFs reach values as large as for "magnetosomes" that are natural magnetic nanoparticles typically ~40 nm found in certain bacteria, which can be grown artificially but with much lower yield compared to chemical synthesis such as the polyol route. This work aims at better understanding the structure-property relationships, linking the internal IONF nanostructure as observed by HR-TEM to their magnetic properties. A library of mono- and multicore IONFs is presented, with diameters ranging from 11 to 30 nm in a narrow size distribution. More particularly, by relating their structural features to their magnetic properties investigated by utilizing AC magnetometry over a wide range of alternating magnetic field conditions, we showed that the SAR values of all synthesized batches vary with overall diameter and number of constituting cores.

10.
Mol Pharm ; 21(6): 2767-2780, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38736196

RESUMEN

Erastin can induce ferroptosis in tumor cells as an effective small molecule inhibitor. However, its application is hampered by a lack of water solubility. This study investigated the effects of superparamagnetic iron oxide (SPIO)-erastin-polyethylene glycol (PEG) nanoparticles prepared by loading SPIO-PEG nanoparticles with erastin on ferroptosis. SPIO-erastin-PEG nanoparticles exhibited square and spherical shapes with good dispersibility. The zeta potential and hydrodynamic size of SPIO-erastin-PEG were measured as (-37.68 ± 2.706) mV and (45.75 ± 18.88) nm, respectively. On T2-weighted imaging, the nanosystem showed significant contrast enhancement compared to no-enhancement magnetic resonance imaging (MRI). SPIO-erastin-PEG induced ferroptosis by increasing reactive oxygen species and iron content and promoting the accumulation of lipid peroxides and the degradation of glutathione peroxidase 4. Pharmacokinetic experiments revealed a half-life of 1.25 ± 0.05 h for the SPIO-erastin-PEG solution in circulation. Moreover, significant antitumorigenic effects of SPIO-erastin-PEG have been demonstrated in 5-8F cells and mouse-bearing tumors. These results indicated that the synthesized SPIO-erastin-PEG nanoplatform could induce ferroptosis effects in vitro and in vivo while exhibiting favorable physical characteristics. This approach may provide a new strategy for theranostic nanoplatform for nasopharyngeal cancer.


Asunto(s)
Ferroptosis , Neoplasias Nasofaríngeas , Polietilenglicoles , Ferroptosis/efectos de los fármacos , Animales , Polietilenglicoles/química , Ratones , Humanos , Neoplasias Nasofaríngeas/tratamiento farmacológico , Línea Celular Tumoral , Imagen por Resonancia Magnética/métodos , Especies Reactivas de Oxígeno/metabolismo , Nanopartículas Magnéticas de Óxido de Hierro/química , Ratones Endogámicos BALB C , Ratones Desnudos , Ensayos Antitumor por Modelo de Xenoinjerto , Compuestos Férricos/química , Femenino , Piperazinas
11.
Pharmacol Res ; 207: 107333, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39089399

RESUMEN

The prognosis for Cholangiocarcinoma (CCA) is unfavorable, necessitating the development of new therapeutic approach such as magnetic hyperthermia therapy (MHT) which is induced by magnetic nano-particle (MNPs) drug to bridge the treatment gap. Given the deep location of CCA within the abdominal cavity and proximity to vital organs, accurately predict the individualized treatment effects and safety brought by the distribution of MNPs in tumor will be crucial for the advancement of MHT in CCA. The Mimics software was used in this study to conduct three-dimensional reconstruction of abdominal computed tomography (CT) and magnetic reso-nance imaging images from clinical patients, resulting in the generation of a realistic digital geometric model representing the human biliary tract and its adjacent structures. Subsequently, The COMSOL Multiphysics software was utilized for modeling CCA and calculating the heat transfer law resulting from the multi-regional distribution of MNPs in CCA. The temperature within the central region of irregular CCA measured approximately 46°C, and most areas within the tumor displayed temperatures surpassing 41°C. The temperature of the inner edge of CCA is only 39 ∼ 41℃, however, it can be ameliorated by adjusting the local drug concentration through simulation system. For CCA with diverse morphologies and anatomical locations, the multi-regional distribution patterns of intratumoral MNPs and a slight overlap of drug distribution areas synergistically enhance intratumoral temperature while ensuring treatment safety. The present study highlights the practicality and imperative of incorporating personalized intratumoral MNPs distribution strategy into clinical practice for MHT, which can be achieved through the development of an integrated simulation system which incorporates medical image data and numerical calculations.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Hipertermia Inducida , Colangiocarcinoma/terapia , Colangiocarcinoma/diagnóstico por imagen , Colangiocarcinoma/tratamiento farmacológico , Humanos , Hipertermia Inducida/métodos , Neoplasias de los Conductos Biliares/terapia , Neoplasias de los Conductos Biliares/diagnóstico por imagen , Neoplasias de los Conductos Biliares/tratamiento farmacológico , Simulación por Computador , Nanopartículas Magnéticas de Óxido de Hierro/química , Modelos Biológicos
12.
Int Microbiol ; 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39105888

RESUMEN

The spread of microbial resistance is a threat to public health. In this study, the anti-microbial, anti-biofilm, and efflux pump inhibitory effects of ellagic acid-loaded magnetic nanoparticles (Fe3O4NPs@EA) against beta-lactamase producing Escherichia coli isolates have been investigated. The effects of Fe3O4 NPs@EA on the growth inhibition of E. coli isolates were determined by disc diffusion method and determining the minimum inhibitory concentration was done using broth micro-dilution method. The anti-biofilm effect of nanoparticles was investigated using the microplate method. The efflux pump inhibitory effect of nanoparticles was investigated using cart-wheel method and by investigating the effect of nanoparticles on acrB and tolC genes expression levels. Fe3O4 NPs@EA showed anti-bacterial effects against test bacteria, and the MIC of these nanoparticles varied from 0.19 to 1.56 mg/mL. These nanoparticles caused a 43-62% reduction in biofilm formation of test bacteria compared to control. Furthermore, efflux pump inhibitory effect of these nanoparticles was confirmed at a concentration of 1/8 MIC, and the expression of acrB and tolC genes decreased in bacteria treated with 1/4 MIC Fe3O4 NPs@EA. According to the results, the use of nanoparticles containing ellagic acid can provide a basis for the development of new treatments against drug-resistant E. coli. This substance may improve the concentration of antibiotics in the bacterial cell and increase their effectiveness by inhibiting the efflux in E. coli isolates.

13.
Nanotechnology ; 35(32)2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38701766

RESUMEN

One of the global challenges for living things is to provide pollution and harmful microbes-free environment. In this study, magnetically retrievable spinel-structured manganese zinc ferrite (Mn0.5Zn0.5Fe2O4) (MZF) was synthesized by a facile solvothermal method. Further, the MZF with different weight percentages (10 wt%, 50 wt%, and 80 wt%) were supported on reduced graphene oxide (rGO). The phase purity and morphology of MZF and MZF/rGO nanocomposite were confirmed by x-ray diffraction technique and scanning electron microscopy, respectively. The Fourier transform infrared spectroscopy, Raman, UV-visible spectroscopy, and thermogravimetric analyses of the as-synthesized nanocomposites were examined for the detection of various chemical groups, band gap, and thermal properties, respectively. The MZF/rGO nanocomposite exhibited significant antibacterial and antifungal activity againstEggerthella lenta, Enterococcus faecalis, Klebsiella pneumonia, Pseudomonas aeruginosa,andCandida albicanscompared to bare MZF and rGO. The high surface area of rGO plays a crucible role in antimicrobial analysis. Additionally, the antibacterial and antifungal activity is compared by synthesizing various metal ferrites such as MnFe2O4, ZnFe2O4, and Fe3O4. The 50 wt% MZF/rGO nanocomposite exhibits significantly high antibacterial activity. However, 10 wt% MZF/rGO nanocomposite shows good antifungal activity than Fe3O4, MnFe2O4, ZnFe2O4, MnZnFe2O4, 50 wt%, and 80 wt% MZF/rGO nanocomposites. These findings suggest that the prepared ferrite nanocomposites hold promise for microbial inhibition.


Asunto(s)
Bacterias , Compuestos Férricos , Hongos , Grafito , Nanocompuestos , Grafito/química , Grafito/farmacología , Compuestos Férricos/química , Compuestos Férricos/farmacología , Nanocompuestos/química , Hongos/efectos de los fármacos , Bacterias/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/química , Antiinfecciosos/farmacología , Antiinfecciosos/química , Antifúngicos/farmacología , Antifúngicos/química , Zinc/química , Zinc/farmacología , Óxido de Aluminio , Óxido de Magnesio
14.
Nanotechnology ; 35(19)2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38294432

RESUMEN

NiCr2O4nanoparticles with average particle size ∼15 nm, a single-domain size maintains the bulk canted antiferromagnetic ground state, were synthesized by a microwave combustion method. The magnetic behavior was carefully investigated by static and dynamic magnetic susceptibility measurements. In addition to a spin-glass-like behavior below paramagnetic-ferrimagnetic transition atTC, the NiCr2O4nanoparticles demonstrate a low-temperature cluster spin glass transition below the spin canting transitionTS, which manifests itself as a magnetic anomaly peak around ∼12 K (at 100 Oe) in the zero-field cooled magnetization with a relatively stronger field dependence in a 'de Almeida-Thouless' line for spin glasses. The AC susceptibility analyses in different approaches demonstrate a larger relative peak temperature variation per frequency decade and a longer characteristic relaxation time in the order of 0.04 and 10-7s, against 0.01 and 10-9s for the high-temperature blocking, indicating the slow spin dynamics for the low-temperature cluster glassy phase. A field-temperature magnetic phase diagram is proposed for the single-domain NiCr2O4nanoparticles.

15.
Mol Biol Rep ; 51(1): 975, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39259442

RESUMEN

BACKGROUND: Many methods are used for cancer treatment, especially chemotherapy. In addition to the their therapeutic effects, chemotherapeutic drugs also have serious disadvantages, such as not being cell and tissue-specific, causing toxicity in many tissues, and developing drug resistance. Many methods, especially nanocarriers, have been designed to overcome these disadvantages. METHODS AND RESULTS: In this study, we synthesized mesoporous silica iron oxide nanoparticles with different pore diameters and loaded idarubicin (6MFe3O4-NH2-IDA and 35MFe3O4-NH2-IDA). The synthesized molecules were characterized using FT-IR, XRD, and SEM methods. The cytotoxic effects of unbound idarubicin and idarubicin-loaded nanoparticles on MCF7 and HL-60 cell lines were examined by MTT test. Additionally, the expression of anti-apoptotic (Survivin and BCL-2) and apoptotic (BAX, PUMA, and NOXA) genes of the nanoparticles were measured by PCR method. As a result of the analyses, it was seen that nanoparticles with the desired properties and sizes were synthesized. In MTT analysis, it was observed that both nanoparticles dramatically decreased the IC50 value in cell lines. However, the 35MFe3O4-NH2-IDA molecule was found to have lower IC50 values. IC50 values ​​for pristine IDA, 6MFe3O4-NH2, and 35MFe3O4-NH2 at 24 h were found to be 3.56, 1.24 and 0.25 µM in the MCF7 cell line and 4.15, 1.16 and 0.34 µM in the HL-60 cell line, respectively. Additionally, apoptotic gene expression increased, and anti-apoptotic gene expression decreased. CONCLUSIONS: Our study demonstrates that the effectiveness of idarubicin can be significantly enhanced by its application with mesoporous nanocarriers. This enhancement is attributed to the controlled release of idarubicin from the nanocarrier, which circumvents drug resistance mechanisms, improves drug solubility, and increases the drug-carrying capacity per unit volume due to the porous structure of the carrier. These findings underscore the potential of the synthesized nanocarrier in cancer treatment and provide a clear direction for future research in this field.


Asunto(s)
Apoptosis , Idarrubicina , Nanopartículas de Magnetita , Humanos , Idarrubicina/farmacología , Apoptosis/efectos de los fármacos , Células MCF-7 , Células HL-60 , Nanopartículas de Magnetita/química , Línea Celular Tumoral , Portadores de Fármacos/química , Dióxido de Silicio/química , Dióxido de Silicio/farmacología , Antineoplásicos/farmacología , Supervivencia Celular/efectos de los fármacos , Porosidad
16.
Anal Bioanal Chem ; 416(22): 4823-4831, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38981912

RESUMEN

Biomarkers screening is a benefit approach for early diagnosis of major diseases. In this study, magnetic nanoparticles (MNPs) have been utilized as labels to establish a multi-line immunochromatography (MNP-MLIC) for simultaneous detection of carcinoembryonic antigen (CEA), carbohydrate antigen 199 (CA 19-9), and alpha-fetoprotein (AFP) in a single serum sample. Under the optimal parameters, the three biomarkers can be rapidly and simultaneously qualitative screening within 15 min by naked eye. As for quantitative detection, the MNP-MLIC test strips were precisely positioned and captured by a smartphone, and signals on the test and control lines were extracted by ImageJ software. The signal ratio of test and control lines has been calculated and used to plot quantitative standard curves with the logarithmic concentration, of which the correlation coefficients are more than 0.99, and the limit of detection for CEA, CA 19-9, and AFP were 0.60 ng/mL, 1.21 U/mL, and 0.93 ng/mL, respectively. The recoveries of blank serum were 75.0 ~ 112.5% with the relative standard deviation ranging from 2.5 to 15.3%, and the specificity investigation demonstrated that the MNP-MLIC is highly specific to the three biomarkers. In conclusion, the developed MNP-MLIC offers a rapid, simple, accurate, and highly specific method for simultaneously detecting multiple biomarkers in serum samples, which provides an efficient and accurate approach for the early diagnosis of diseases.


Asunto(s)
Antígeno Carcinoembrionario , Cromatografía de Afinidad , Límite de Detección , Nanopartículas de Magnetita , alfa-Fetoproteínas , Humanos , Antígeno Carcinoembrionario/sangre , alfa-Fetoproteínas/análisis , Nanopartículas de Magnetita/química , Cromatografía de Afinidad/métodos , Biomarcadores de Tumor/sangre , Antígeno CA-19-9/sangre , Biomarcadores/sangre
17.
Anal Bioanal Chem ; 416(13): 3239-3250, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38573343

RESUMEN

Cocaine and antidepressants rank high globally in substance consumption, emphasizing their impact on public health. The determination of these compounds and related substances in biological samples is crucial for forensic toxicology. This study focused on developing an innovative analytical method for the determination of cocaine, antidepressants, and their related metabolites in postmortem blood samples, using unmodified commercial Fe3O4 nanoparticles as a sorbent for dispersive magnetic solid-phase extraction (m-d-SPE), coupled with liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) analysis. An aliquot of 100 µL of whole blood and 5 µL of the internal standard pool were added to 30 mg of nanoparticles. The nanoparticles were separated from the sample using a neodymium magnet inserted into a 3D-printed microtube rack. The liquid was then discarded, followed by desorption with 300 µL of 1/1/1 acetonitrile/methanol/ethyl acetate. The sample was vortexed and separated, and 1.5 µL of the organic supernatant was injected into the LC-MS/MS. The method was acceptably validated and successfully applied to 263 postmortem blood samples. All samples evaluated in this study were positive for at least one substance. The most frequent analyte was benzoylecgonine, followed by cocaine and cocaethylene. The most common antidepressants encountered in the analyzed samples were citalopram and fluoxetine, followed by fluoxetine's metabolite norfluoxetine. This study describes the first report of this sorbent in postmortem blood analysis, demonstrating satisfactory results for linearity, precision, accuracy, and selectivity for all compounds. The method's applicability was confirmed, establishing it as an efficient and sustainable alternative to traditional techniques for forensic casework.


Asunto(s)
Antidepresivos , Cocaína , Toxicología Forense , Nanopartículas de Magnetita , Extracción en Fase Sólida , Espectrometría de Masas en Tándem , Humanos , Cocaína/sangre , Cocaína/análogos & derivados , Antidepresivos/sangre , Espectrometría de Masas en Tándem/métodos , Toxicología Forense/métodos , Extracción en Fase Sólida/métodos , Nanopartículas de Magnetita/química , Cromatografía Liquida/métodos , Límite de Detección , Detección de Abuso de Sustancias/métodos , Masculino , Femenino , Adulto
18.
Anal Bioanal Chem ; 416(7): 1657-1665, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38319356

RESUMEN

In this study, titanium (IV)-immobilized magnetic nanoparticles (Ti4+-PTL-MNPs) were firstly synthesized via a one-step aqueous self-assembly of lysozyme nanofilms for efficient phosphopeptide enrichment. Under physiological conditions, lysozymes readily self-organized into phase-transitioned lysozyme (PTL) nanofilms on Fe3O4@SiO2 and Fe3O4@C MNP surfaces with abundant functional groups, including -NH2, -COOH, -OH, and -SH, which can be used as multiple linkers to efficiently chelate Ti4+. The obtained Ti4+-PTL-MNPs possessed high sensitivity of 0.01 fmol µL-1 and remarkable selectivity even at a mass ratio of ß-casein to BSA as low as 1:400 for phosphopeptide enrichment. Furthermore, the synthesized Ti4+-PTL-MNPs can also selectively identify low-abundance phosphopeptides from extremely complicated human serum samples and their rapid separation, good reproducibility, and excellent recovery were also proven. This one-step self-assembly of PTL nanofilms facilitated the facile and efficient surface functionalization of various nanoparticles for proteomes/peptidomes.


Asunto(s)
Nanopartículas de Magnetita , Fosfopéptidos , Humanos , Titanio , Muramidasa , Dióxido de Silicio , Reproducibilidad de los Resultados
19.
Anal Bioanal Chem ; 416(1): 203-214, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37914955

RESUMEN

In this study, an integrated QuEChERS method was developed for the rapid determination of 22 per- and polyfluoroalkyl substances (PFASs) in milk by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The extraction and purification processes were combined into one step with this method. Meanwhile, the solid-liquid separation was carried out by magnetic suction (Fe3O4-SiO2) instead of the centrifugal process. The primary experimental parameters were optimized, including the type of extraction solvent, the amounts of magnetic nanomaterials (Fe3O4-SiO2), and the purification materials (ZrO2 and C18). The developed method exhibits high precision (RSDs < 9.9%), low limits of detection (0.004-0.079 µg/kg) and limits of quantitation (0.01-0.26 µg/kg), and acceptable recovery (71.7-116%) under optimized conditions. The developed integrated QuEChERS method had clear superiority in terms of sample pretreatment time, operating procedures, reagent amount, and recovery. This makes it an excellent alternative analytical technique for PFAS residue measurement at low micrograms-per-kilogram ranges with desirable sensitivity.


Asunto(s)
Fluorocarburos , Espectrometría de Masas en Tándem , Animales , Cromatografía Liquida , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Extracción en Fase Sólida/métodos , Leche/química , Dióxido de Silicio , Cromatografía Líquida con Espectrometría de Masas , Fluorocarburos/análisis
20.
Bioorg Chem ; 151: 107673, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39068719

RESUMEN

In this study, Bacillus tequilensis TB5 α-amylase from rice-milled by-products (rice bran and de-oiled rice bran) was successfully immobilized onto biologically synthesized magnetic nanoparticles fabricated with chitosan (MNP-Ch) and characterized via different biophysical techniques. Furthermore, the study emphasized incorporating this nanostructure framework (MNP@2mgchitosan_DORB-amy and MNP@3mgchitosan_RB-amy) to offer diverse applications, including enzymatic desizing, cleaning starchy stains, and treating synthetic starchy wastewater. An enzyme loading of > 90 % for both enzymes indicated increased binding sites due to the functional moieties of chitosan on the MNP. The Km was 0.28 and 0.31 mg/mL for the immobilized and free forms of DORB-amy, respectively, and 0.18 and 0.27 mg/mL for the immobilized and free forms of RB-amy, respectively. A low Km indicated an increased affinity of MNP-Ch-immobilized forms of enzymes toward the substrate. The performance of both immobilized enzymes improved at a wide range of pH and temperature, which may be attributed to the covalent binding of the enzyme on to the MNP-Ch. The nanobiocatalysts in the detergent act synergistically to fade the starchy stains. Furthermore, an 8-9 TEGEWA scale rating with > 11 % of starch removal was obtained through the biodesizing of starch-sized cotton fabric. The nanobiocatalyst efficiently decomposed starch and liberated 650-670 mg/L of reducing sugar from the synthetic wastewater, therefore offering promising opportunities for its exploration in a wastewater treatment plant. Thus, the study recommends the potential exploration of sturdy matrices like MNP to offer remarkable applications with maximum operational stability, easier recovery, and higher efficiency.


Asunto(s)
Bacillus , Biocatálisis , Quitosano , Detergentes , Enzimas Inmovilizadas , Almidón , Aguas Residuales , alfa-Amilasas , alfa-Amilasas/metabolismo , alfa-Amilasas/química , Quitosano/química , Aguas Residuales/química , Almidón/química , Almidón/metabolismo , Bacillus/enzimología , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Detergentes/química , Nanopartículas de Magnetita/química , Textiles , Estructura Molecular , Purificación del Agua/métodos , Concentración de Iones de Hidrógeno
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA