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1.
J Biomech Eng ; 146(1)2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37773642

RESUMEN

High-grade gliomas (HGG) are the most common primary brain malignancy and continue to be associated with a dismal prognosis (median survival rate of 15-18 months) with standard of care therapy. Magnetic hyperthermia therapy (MHT) is an emerging intervention that leverages the ferromagnetic properties of magnetic iron-oxide nanoparticles (MIONPs) to target cancer cells that are otherwise left behind after resection. We report a novel port device to facilitate localization, delivery, and temperature measurement of MIONPs within a target lesion for MHT therapy. We conducted an in-depth literature and intellectual property review to define specifications of the conceived port device. After setting the design parameters, a thorough collaboration with neurological surgeons guided the iterative modeling process. A prototype was developed using Fusion 360 (Autodesk, San Rafael, CA) and printed on a Form 3 printer (Formlabs, Medford, MA) in Durable resin. The prototype was then tested in a phantom skull printed on a Pro-Jet 660Pro 3D printer (3D Systems, Rock Hill, SC) and a brain model based on mechanical and electrochemical properties of native brain tissue. This phantom underwent MHT heating tests using an alternating magnetic field (AMF) sequence based on current MHT workflow. Successful localization, delivery, and temperature measurement were demonstrated. The purpose of this study was twofold: first, to create and validate the procedural framework for a novel device, providing the groundwork for an upcoming comprehensive animal trial and second, to elucidate a cooperative approach between engineers and clinicians that propels advancements in medical innovation.


Asunto(s)
Neoplasias Encefálicas , Glioma , Hipertermia Inducida , Animales , Glioma/terapia , Neoplasias Encefálicas/terapia , Encéfalo , Fenómenos Magnéticos
2.
Int J Mol Sci ; 25(16)2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39201784

RESUMEN

Magnetic Fe3O4 nanoparticles (MNPs) functionalized with (3-aminopropylo)trietoksysilan (APTES) or N-carboxymethylchitosan (CMC) were proposed as nanocarriers of methotrexate (MTX) to target ovarian cancer cell lines. The successful functionalization of the obtained nanostructures was confirmed by FT-IR spectroscopy. The nanoparticles were characterized by transmission electron spectroscopy (TEM) and dynamic light scattering (DLS) techniques. Their potential zeta, magnetization, and hyperthermic properties were also explored. MTX was conjugated with the nanocarriers by ionic bonds or by amide bonds. The drug release kinetics were examined at different pH and temperatures. The MTT assay showed no toxicity of the MNPs[APTES] and MNPs[CMC]. Finally, the cytotoxicity of the nanostructures with MTX attached towards the ovarian cancer cells was measured. The sensitivity and resistance to methotrexate was determined in simplistic 2D and spheroid 3D conditions. The cytotoxicity tests of the tested nanostructures showed similar values for inhibiting the proliferation of ovarian cancer cells as methotrexate in its free form. Conjugating MTX with nanoparticles allows the drug to be directed to the target site using an external magnetic field, reducing overall toxicity. Combining this approach with hyperthermia could enhance the therapeutic effect in vivo compared to free MTX, though further research on advanced 3D models is needed.


Asunto(s)
Metotrexato , Neoplasias Ováricas , Metotrexato/química , Metotrexato/farmacología , Metotrexato/administración & dosificación , Femenino , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/patología , Humanos , Línea Celular Tumoral , Nanopartículas de Magnetita/química , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas Magnéticas de Óxido de Hierro/química , Liberación de Fármacos , Antimetabolitos Antineoplásicos/farmacología , Antimetabolitos Antineoplásicos/química , Antimetabolitos Antineoplásicos/administración & dosificación , Supervivencia Celular/efectos de los fármacos
3.
Cutan Ocul Toxicol ; 43(1): 69-74, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37908111

RESUMEN

PURPOSE: Retinoblastoma (RB) is one of the most important cancers in children with a higher rate of prevalence in developing countries. Despite different approaches to the treatment of RB, it seems necessary to discover a new approach to its treatment. Today, mitochondria are recognised as an important target in the treatment of cancer. Superparamagnetic iron oxide nanoparticles (SPIONs) have been studied by researchers due to their important biological effects. METHODS: In this study, the effects of SPIONs on mitochondria isolated from Y79 retinoblastoma cells were investigated. RESULTS: The results showed that SPIONs were able to increase the reactive oxygen species (ROS) level and subsequently damage the mitochondrial membrane and release cytochrome c a as one of the important pro-apoptotic proteins of RB mitochondria. Furthermore, the results indicated a decrease in cell viability and an increase in caspase-3 activity in Y79 retinoblastoma cells. CONCLUSIONS: These events can lead to the killing of cancerous mitochondria. Our results suggest that SPIONs can cause mitochondrial dysfunction and death in RB mitochondria.


Asunto(s)
Neoplasias de la Retina , Retinoblastoma , Niño , Humanos , Retinoblastoma/tratamiento farmacológico , Retinoblastoma/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Nanopartículas Magnéticas de Óxido de Hierro/toxicidad , Mitocondrias , Neoplasias de la Retina/tratamiento farmacológico , Neoplasias de la Retina/metabolismo
4.
Small ; 19(49): e2302856, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37596716

RESUMEN

Magnetic iron oxide nanoparticles (MIONs) based T2 -weighted magnetic resonance imaging (MRI) contrast agents (CAs) are liver-specific with good biocompatibility, but have been withdrawn from the market and replaced with Eovist (Gd-EOB-DTPA) due to their inherent limitations (e.g., susceptibility to artifacts, high magnetic moment, dark signals, long processing time of T2 imaging, and long waiting time for patients after administration). Without the disadvantages of Gd-chelates and MIONs, the recently emerging exceedingly small MIONs (ES-MIONs) (<5 nm) are promising T1 CAs for MRI. However, there are rare review articles focusing on ES-MIONs for T1 -weighted MRI. Herein, the recent progress of ES-MIONs, including synthesis methods (the current basic synthesis methods and improved methods), surface modifications (artificial polymers, natural polymers, zwitterions, and functional protein), T1 -MRI visual strategies (structural remodeling, reversible self-assemblies, metal ions doped, T1 /T2 dual imaging modes, and PET/MRI strategy), and imaging-guided cancer therapy (chemotherapy, gene therapy, ferroptosis therapy, photothermal therapy, photodymatic therapy, radiotherapy, immuotherapy, sonodynamic therapy, and multimode therapy), is summarized. The detailed description of synthesis methods and applications of ES-MIONs in this review is anticipated to attract extensive interest from researchers in different fields and promote their participation in the establishment of ES-MIONs based nanoplatforms for tumor theranostics.


Asunto(s)
Neoplasias , Humanos , Neoplasias/diagnóstico por imagen , Neoplasias/terapia , Imagen por Resonancia Magnética/métodos , Medios de Contraste/química , Nanopartículas Magnéticas de Óxido de Hierro , Polímeros
5.
Environ Res ; 225: 115588, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-36858301

RESUMEN

The removal of Cr(VI) and As(V) from aqueous solutions has been a worldwide concern. In this study, Typha biochar (FBC) with magnetic iron oxide was prepared by impregnating Typha with FeCl3 and performing pyrolysis, and the possible mechanism of Cr(VI) and As(V) removal was investigated by combining characterization means and adsorption experiments. The results showed that the modified Typha biochar is rich in pores and has the potential to eliminate Cr and As through processes such as exchange and reduction. The single molecule uptake capacities of FBC for Cr(VI) and As(V) were 32.82 and 21.56 mg g-1, respectively. The adsorption process is spontaneous heat absorption, and the adsorption results are also consistent with the proposed secondary kinetic model. FBC still had >60% removal efficiency in the second and third reuse of Cr(VI), indicating its good recyclability. Therefore, this study confirms that FBC can effectively remove both Cr(VI) and As(V).


Asunto(s)
Typhaceae , Contaminantes Químicos del Agua , Compuestos Férricos , Cromo , Carbón Orgánico , Adsorción , Contaminantes Químicos del Agua/análisis
6.
Small ; 18(27): e2203033, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35665598

RESUMEN

In vivo, natural biomaterials are frequently anisotropic, exhibiting directional microstructures and mechanical properties. It remains challenging to develop such anisotropy in synthetic materials. Here, a facile one-step approach for in situ fabrication of hydrogels with hierarchically anisotropic architectures and direction-dependent mechanical properties is proposed. The anisotropic hydrogels, composed of a fibrous gel network (0.1 wt%), cross-linked with magnetic nanoparticles (spheres, rods, and wires, <0.1 wt%) are readily formed in the presence of very low magnetic fields (<20 mT). The anisotropy of the nanoparticles is transduced to the polymer network, leading to macroscopic anisotropy, for instance, in mechanical properties. Electrostatic repulsion by the negatively charged nanoparticles induces an additional layer of order in the material, perpendicular to the magnetic field direction. The straightforward fabrication strategy allows for stepwise deposition of layers with different degrees or directions of anisotropy, which enables the formation of complex structures that are able to mimic some of the complex hierarchical architectures found in biology. It is anticipated that this approach of hydrogel alignment may serve as a guide for designing advanced biomaterials in tissue engineering.


Asunto(s)
Biomimética , Hidrogeles , Anisotropía , Materiales Biocompatibles/química , Hidrogeles/química , Ingeniería de Tejidos
7.
BMC Cancer ; 22(1): 1062, 2022 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-36241982

RESUMEN

BACKGROUND: Current pre-operative Sentinel Lymph Node (SLN) mapping using dual tracing is associated with drawbacks (radiation exposure, logistic challenges). Superparamagnetic iron oxide (SPIO) is a non-inferior alternative for SLN mapping in breast cancer patients. Limited research has been performed on SPIO use and pre-operative MRI in melanoma patients to identify SLNs.  METHODS: Healthy participants underwent MRI-scanning pre- and post SPIO-injection during 20 min. Workflow protocols varied in dosage, massage duration, route of administration and injection sites. The first lymph node showing a susceptibility artefact caused by SPIO accumulation was considered as SLN. RESULTS: Artefacts were identified in 5/6 participants. Two participants received a 0.5 ml subcutaneous injection and 30-s massage, of which one showed an artefact after one hour. Four participants received a 1.0 ml intracutaneous injection and two-minute massage, leading to artefacts in all participants. All SLNs were observed within five minutes, except after lower limb injection (30 min). CONCLUSION: SPIO and pre-operative MRI-scanning seems to be a promising alternative for SLN visualization in melanoma patients. An intracutaneous injection of 1.0 ml SPIO tracer, followed by a two-minute massage seems to be the most effective technique, simplifying the pre-operative pathway. Result will be used in a larger prospective study with melanoma patients. TRIAL REGISTRATION: ClinicalTrials.gov (NCT05054062) - September 9, 2021.


Asunto(s)
Melanoma , Ganglio Linfático Centinela , Humanos , Compuestos Férricos , Voluntarios Sanos , Ganglios Linfáticos/patología , Nanopartículas Magnéticas de Óxido de Hierro , Imagen por Resonancia Magnética , Melanoma/diagnóstico por imagen , Melanoma/patología , Proyectos Piloto , Estudios Prospectivos , Ganglio Linfático Centinela/diagnóstico por imagen , Ganglio Linfático Centinela/patología , Biopsia del Ganglio Linfático Centinela/métodos , Flujo de Trabajo
8.
Environ Res ; 214(Pt 3): 114000, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35948150

RESUMEN

This paper reports a simple method of designing and synthesizing magnetic iron oxide (IO) integrated locust bean gum-cl-polyacrylonitrile hydrogel nanocomposites (LBG-cl-PAN/IONP) by in situ mineralization of iron ions in a hydrogel matrix. A two-step gel crosslink method followed by co-precipitation method was used to prepare these novel hydrogels embedded with magnetic iron oxide nanoparticles. The LBG-cl-PAN/IONP hydrogel nanocomposite (HNC) were tested in batch adsorption experiments for their ability to remove a cationic dyes, methylene blue (MB) & Methyl violet (MV), from aqueous solution. In order to analyze the LBG-cl-PAN/IONP HNC, FTIR, XRD, XPS, VSM, TEM, and EDX techniques were applied. Numerous operating parameters were studied, including the amount of adsorbent, the contact time, pH, temperature, the dye concentration, and the coexisting ion concentration. According to the Langmuir isotherm model, MB and MV had maximum monolayer adsorptive capacities of 1250 and 1111 mg/g, respectively. LBG-cl-PAN/IONP HNC controlled IONP oxidation as well as sustained adsorptive removal over a wide pH range (7-10). The key mechanism of adsorption consisted of electrostatic interaction and ion exchange. For successful use in successive cycles after regeneration using HNO3 as eluent, the LBG-cl-PAN/IONP HNC can easily be reused. As a material, the LBG-cl-PAN/IONP HNC is a promising sorbent or composite material for removing toxic dyes from water, and therefore can be applied to enhance water and wastewater treatment technology. Additionally, we have briefly evaluated LBG-cl-PAN/IONP HNC for antibacterial and supercapacitor applications. According to our knowledge, this is the first report describing the use of LBG-cl-PAN/IONP HNC multifunctional efficacy as an excellent sorbent, antibacterial and electrochemical supercapacitor applications.


Asunto(s)
Nanocompuestos , Contaminantes Químicos del Agua , Adsorción , Antibacterianos , Colorantes , Galactanos , Violeta de Genciana , Hidrogeles , Concentración de Iones de Hidrógeno , Cinética , Nanopartículas Magnéticas de Óxido de Hierro , Mananos , Azul de Metileno , Gomas de Plantas , Agua
9.
J Nanobiotechnology ; 20(1): 350, 2022 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-35908057

RESUMEN

Magnetic resonance imaging (MRI) has been widely using in clinical diagnosis, and contrast agents (CAs) can improve the sensitivity MRI. To overcome the problems of commercial Gd chelates-based T1 CAs, commercial magnetic iron oxide nanoparticles (MIONs)-based T2 CAs, and reported exceedingly small MIONs (ES-MIONs)-based T1 CAs, in this study, a facile co-precipitation method was developed to synthesize biodegradable and biocompatible ES-MIONs with excellent water-dispersibility using poly (aspartic acid) (PASP) as a stabilizer for T1-weighted MRI of tumors. After optimization of the synthesis conditions, the final obtained ES-MION9 with 3.7 nm of diameter has a high r1 value (7.0 ± 0.4 mM-1 s-1) and a low r2/r1 ratio (4.9 ± 0.6) at 3.0 T. The ES-MION9 has excellent water dispersibility because of the excessive -COOH from the stabilizer PASP. The pharmacokinetics and biodistribution of ES-MION9 in vivo demonstrate the better tumor targetability and MRI time window of ES-MION9 than commercial Gd chelates. T1-weighted MR images of aqueous solutions, cells and tumor-bearing mice at 3.0 T or 7.0 T demonstrate that our ES-MION9 has a stronger capability of enhancing the MRI contrast comparing with the commercial Gd chelates. The MTT assay, live/dead staining of cells, and H&E-staining indicate the non-toxicity and biosafety of our ES-MION9. Consequently, the biodegradable and biocompatible ES-MION9 with excellent water-dispersibility is an ideal T1-weighted CAs with promising translational possibility to compete with the commercial Gd chelates.


Asunto(s)
Imagen por Resonancia Magnética , Neoplasias , Animales , Medios de Contraste , Nanopartículas Magnéticas de Óxido de Hierro , Imagen por Resonancia Magnética/métodos , Ratones , Neoplasias/patología , Distribución Tisular , Agua
10.
Nano Lett ; 21(16): 6740-6747, 2021 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-34387494

RESUMEN

The mechanical environment of a cell is not constant. This dynamic behavior is exceedingly difficult to capture in (synthetic) in vitro matrices. This paper describes a novel, highly adaptive hybrid hydrogel composed of magnetically sensitive magnetite nanorods and a stress-responsive synthetic matrix. Nanorod rearrangement after application of (small) magnetic fields induces strain in the network, which results in a strong (over 10-fold) stiffening even at minimal (2.5 wt %) nanorod concentrations. Moreover, the stiffening mechanism yields a fast and fully reversible response. In the manuscript, we quantitatively analyze that forces generated by the particles are comparable to cellular forces. We demonstrate the value of magnetic stiffening in a 3D MCF10A epithelial cell experiment, where simply culturing on top of a permanent magnet gives rise to changes in the cell morphology. This work shows that our hydrogels are uniquely suited as 3D cell culture systems with on-demand adaptive mechanical properties.


Asunto(s)
Técnicas de Cultivo de Célula , Hidrogeles , Fenómenos Magnéticos , Magnetismo , Estrés Mecánico
11.
Artif Organs ; 45(11): 1272-1299, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34245037

RESUMEN

Nanoscience has been considered as one of the most substantial research in modern science. The utilization of nanoparticle (NP) materials provides numerous advantages in biomedical applications due to their unique properties. Among various types of nanoparticles, the magnetic nanoparticles (MNPs) of iron oxide possess intrinsic features, which have been efficiently exploited for biomedical purposes including drug delivery, magnetic resonance imaging, Magnetic-activated cell sorting, nanobiosensors, hyperthermia, and tissue engineering and regenerative medicine. The size and shape of nanostructures are the main factors affecting the physicochemical features of superparamagnetic iron oxide nanoparticles, which play an important role in the improvement of MNP properties, and can be controlled by appropriate synthesis strategies. On the other hand, the proper modification and functionalization of the surface of iron oxide nanoparticles have significant effects on the improvement of physicochemical and mechanical features, biocompatibility, stability, and surface activity of MNPs. This review focuses on popular methods of fabrication, beneficial surface coatings with regard to the main required features for their biomedical use, as well as new applications.


Asunto(s)
Nanopartículas Magnéticas de Óxido de Hierro/química , Propiedades de Superficie , Ingeniería Biomédica/métodos , Técnicas Biosensibles , Separación Celular/métodos , Sistemas de Liberación de Medicamentos , Humanos , Imagen por Resonancia Magnética/métodos , Ingeniería de Tejidos
12.
Small ; 16(45): e2003969, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33053265

RESUMEN

Magnetic nanomaterials are a promising class of contrast agents for magnetic resonance imaging (MRI). However, their poor stability and low relaxivity are major challenges hindering their clinical applications. In this study, magnetic theranostic nanoagents based on polydopamine-modified Fe3 O4 (Fe3 O4 @PDA) nanocomposites are fabricated for MRI-guided photothermal therapy (PTT) cancer treatments. Their high transverse relaxivity of 337.8 mM-1 s-1 makes these Fe3 O4 @PDA nanocomposites a promising T2 -weighted MRI contrast agent for cancer diagnosis and image-guided cancer therapy. Due to the good photothermal effect of polydopamine (PDA), the tumors of 4T1 tumor-bearing mice are completely excised by PTT. Most importantly, the PDA shell also improves the stability of the Fe3 O4 @PDA nanocomposites, which contributes to their excellent, long-term performance in MRI and PTT applications. Their good stability, high T2 relaxivity, robust biocompatibility, and satisfactory treatment effect give these Fe3 O4 @PDA nanocomposites great potential for use in cancer theranostics.


Asunto(s)
Nanocompuestos , Nanopartículas , Animales , Indoles , Imagen por Resonancia Magnética , Ratones , Fototerapia , Terapia Fototérmica , Polímeros , Nanomedicina Teranóstica
13.
Small ; 16(41): e2002733, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32945130

RESUMEN

A versatile breast cancer-targeting nanocomposite therapeutic combining docetaxel (DXL), polyvinyl alcohol (PVA) network for controlled release, and silica-protected magnetic iron oxide nanoparticles (Fe3 O4 NPs) for targeted delivery and gold nanoparticles (AuNPs) for plasmonic photothermal therapy (PPTT) is presented in this work. First, the designed nanocomposite is magnetically directed for cancer-targeted therapy confirmed by computerized tomography (CT) scans. Second, 10% DXL by mass is loaded into PVA, a pH and temperature responsive gel, for controlled release. Third, PPTT is confirmed with Au/Fe3 O4 /PVA-10%DXL using a prototype circulation system and then for tumor treatment in vivo; Au/Fe3 O4 /PVA-10%DXL is conveniently directed and the entrapped DXL is selectively released (≈96%) via the interaction of green and near-infrared (NIR) light with the localized surface plasmon resonance of AuNPs. A 75% cell death is reported from in vitro studies with DXL doses as low as 20 µg mL-1 of Au/Fe3 O4 /PVA-10%DXL, and a 70% tumor growth inhibition is demonstrated by in vivo experiments with the biosafety studies confirming minimal side effects to other organs. Overall, the developed Au/Fe3 O4 /PVA-10%DXL has a strong potential to simultaneously enhance CT imaging contrast together with the targeted delivery of DXL.


Asunto(s)
Neoplasias de la Mama , Nanopartículas del Metal , Nanocompuestos , Neoplasias de la Mama/tratamiento farmacológico , Docetaxel , Femenino , Oro , Humanos
14.
Int J Hyperthermia ; 37(3): 100-107, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33426988

RESUMEN

BACKGROUND: Magnetic fluid heating has great potential in the fields of thermal medicine and cryopreservation. However, variations among experimental parameters, analysis methods and experimental uncertainty make quantitative comparisons of results among laboratories difficult. Herein, we focus on the impact of calculating the specific absorption rate (SAR) using Time-Rise and Box-Lucas fitting. Time-Rise assumes adiabatic conditions, which is experimentally unachievable, but can be reasonably assumed (quasi-adiabatic) only for specific and limited evaluation times when heat loss is negligible compared to measured heating rate. Box-Lucas, on the other hand, accounts for heat losses but requires longer heating. METHODS: Through retrospective analysis of data obtained from two laboratories, we demonstrate measurement time is a critical parameter to consider when calculating SAR. Volumetric SAR were calculated using the two methods and compared across multiple iron-oxide nanoparticles. RESULTS: We observed the lowest volumetric SAR variation from both fitting methods between 1-10 W/mL, indicating an ideal SAR range for heating measurements. Furthermore, our analysis demonstrates that poorly chosen fitting method can generate reproducible but inaccurate SAR. CONCLUSION: We provide recommendations to select measurement time for data analysis with either Modified Time-Rise or Box-Lucas method, and suggestions to enhance experimental precision and accuracy when conducting heating experiments.


Asunto(s)
Nanopartículas de Magnetita , Calefacción , Calor , Magnetismo , Estudios Retrospectivos
15.
J Nanobiotechnology ; 18(1): 6, 2020 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-31910856

RESUMEN

BACKGROUND: Haptoglobin is an acute-phase protein used as predicting diagnostic biomarker both in humans (i.e., diabetes, ovarian cancer, some neurological and cardiovascular disorders) and in animals (e.g., bovine mastitis). The latter is a frequent disease of dairy industry with staggering economical losses upon decreased milk production and increased health care costs. Early stage diagnosis of the associated diseases or inflammation onset is almost impossible by conventional analytical manners. RESULTS: The present study demonstrates a simple, rapid, and cost-effective label-free chemiluminescence bioassay based on magnetite nanoparticles (MNPs) for sensitive detection of haptoglobin by employing the specific interaction of hemoglobin-modified MNPs. The resulting haptoglobin-hemoglobin complex inhibits the peroxidase-like activity of luminol/H2O2-hemoglobin-MNPs sensing scheme and reduces the chemiluminescence intensities correspondingly to the innate haptoglobin concentrations. Quantitative detection of bovine haptoglobin was obtained within the range of 1 pg mL-1 to 1 µg mL-1, while presenting 0.89 pg mL-1 limit of detection. Moreover, the influence of causative pathogenic bacteria (i.e., Streptococcus dysgalactiae and Escherichia coli) and somatic cell counts (depicting healthy, sub-clinical and clinical mastitis) on the emitted chemiluminescence radiation were established. The presented bioassay quantitative performances correspond with a standardized assay kit in differentiating dissimilar milk qualities. CONCLUSIONS: Overall, the main advantage of the presented sensing concept is the ability to detect haptoglobin, at clinically relevant concentrations within real milk samples for early bio-diagnostic detection of mastitis and hence adjusting the precise treatment, potentially initiating a positive influence on animals' individual health and hence on dairy farms economy.


Asunto(s)
Biomarcadores/análisis , Haptoglobinas/análisis , Mediciones Luminiscentes , Nanopartículas de Magnetita/química , Animales , Bioensayo , Calibración , Bovinos , Recuento de Células , Nanopartículas de Magnetita/ultraestructura , Leche/microbiología
16.
J Cell Biochem ; 120(2): 1185-1192, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30362604

RESUMEN

Since the morphology of the rooster spermatozoa is different to other animal spermatozoa, the aim of the current study was to investigate the transfection efficiency and cytotoxicity of polyethyleneimine (PEI) coated magnetic iron oxide nanoparticles (MION) on these cells. Liposome/nucleic acid (NA) complexes and PEI-coated MION linked to the labeled oligonucleotides were used. Viability and percentage of exogenous nucleic acid uptake of spermatozoa were measured by flow cytometry analyses. The results showed a significant increase in exogenous nucleic acid uptake by rooster spermatozoa (P < 0.001) when treated with MION-NA complexes in comparison to liposome/NA. There were no significant differences between efficiency of lipid-based transfection agent and MION (P > 0.05) during short incubation period. MION with or without magnetic field, did not show significant cytotoxicity while the lipid-based transfection agent significantly decreased (P < 0.05) the viability of rooster spermatozoa. Results of this study showed that magnetofection and lipofection were both effective methods which increased exogenous nucleic acid uptake by rooster spermatozoa. However, the magnetofection method was more successful in maintaining the cell's survival than lipofection method.

17.
Mikrochim Acta ; 186(12): 852, 2019 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-31776681

RESUMEN

An anion exchange solid-phase sorbent is described. Chitosan coated magnetite nanoparticles were modified with polyethylenimine which is positively charged at pH 3 and therefore can be used for the magnet-supported enrichment of phosphopeptides which are negatively charged at this pH value. A 2-step strategy was used to synthesize the sorbent. The materials were characterized by transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetry and magnetic moment analysis. The anion exchanger was applied to extract phosphopeptides from a ß-casein digest. Characteristic analytical figures include (a) a loading buffer of pH 3, (b) and elution buffer of pH 11, (c) a loading time of 5 min, (d) good selectivity (the ß-casein to BSA ratio is 1:1000), and (e) excellent sensitivity (1 fmol). The optimized method was applied to egg yolk digest, non-fat milk digest, and diluted human serum. Graphical abstractSchematic representation of synthesis of PEI@chitosan@Fe3O4 nanoparticles, and of the enrichment of phosphopeptides by magnetic solid phase extraction prior to the determination of the peptides by MALDI-MS analysis.


Asunto(s)
Quitosano/química , Nanopartículas de Magnetita/química , Fosfopéptidos/aislamiento & purificación , Polietileneimina/química , Adsorción , Animales , Aniones/química , Bovinos , Yema de Huevo/química , Humanos , Leche/química , Tamaño de la Partícula , Fosfopéptidos/sangre , Fosfopéptidos/química , Propiedades de Superficie
18.
Mol Pharm ; 14(5): 1352-1364, 2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-27776215

RESUMEN

Magnetic iron oxide nanoparticles (MIONs) have attracted enormous attention due to their wide applications, including for magnetic separation, for magnetic hyperthermia, and as contrast agents for magnetic resonance imaging (MRI). This review article introduces the methods of synthesizing MIONs, and their application as MRI contrast agents. Currently, many methods have been reported for the synthesis of MIONs. Herein, we only focus on the liquid-based synthesis methods including aqueous phase methods and organic phase methods. In addition, the MIONs larger than 10 nm can be used as negative contrast agents and the recently emerged extremely small MIONs (ES-MIONs) smaller than 5 nm are potential positive contrast agents. In this review, we focus on the ES-MIONs because ES-MIONs avoid the disadvantages of MION-based T2- and gadolinium chelate-based T1-weighted contrast agents.


Asunto(s)
Medios de Contraste/química , Compuestos Férricos/química , Imagen por Resonancia Magnética/métodos , Nanopartículas/química
19.
Nanomedicine ; 13(5): 1607-1616, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28285157

RESUMEN

Thermosensitive yolk-shell nanoparticles were developed as remote-controlled targeting drug delivery platform for multimodal imaging and combined therapy of cancer. The nanoparticles were fabricated using magnetic Fe3O4 nanoparticles as photothermal cores, thermo-responsive poly(N-isopropylacrylamide)-co-1-Vinyl-2-pyrrolidone p(NIPAM-co-NVP) as shells (Fe3O4-PNIPAM), with a hollow space between the two layers for loading of chemotherapeutic drug. The magnetic iron oxide nanoparticle cores could absorb and transform light to heat efficiently upon the irradiation of near infrared (NIR) laser, resulting in the shrink of the PNIPAM shell and the release of chemo-drugs. In vivo fluorescence/photoacoustic images demonstrated that Fe3O4-PNIPAM nanoparticles could accumulate in the tumor after intravenous injection. Upon the irradiation of the NIR laser, DOX-Fe3O4-PNIPAM nanoparticles exhibited outstanding synergistic effect. The tumor inhibition rate increased from 40.3% (DOX-Fe3O4-PNIPAM alone) and 65.2% (Fe3O4-PNIPAM +NIR) to 91.5%. The results demonstrated that the NIR-responsive nanocarrier offers a novel strategy for cancer theranostics and combined therapy of cancer.


Asunto(s)
Rayos Infrarrojos , Imagen Multimodal , Nanopartículas , Animales , Neoplasias de la Mama , Sistemas de Liberación de Medicamentos , Humanos , Ratones , Neoplasias , Células Tumorales Cultivadas
20.
Nano Lett ; 16(9): 5895-901, 2016 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-27513184

RESUMEN

The ultimate goal in cancer therapy and diagnosis is to achieve highly specific targeting to cancer cells. Coated with the source cancer cell membrane specifically derived from the homologous tumors, the nanoparticles are identified with the self-recognition internalization by the source cancer cell lines in vitro and the highly tumor-selective targeting "homing" to the homologous tumor in vivo even in the competition of another heterologous tumor. As the result, MNP@DOX@CCCM nanovehicle showed strong potency for tumor treatment in vivo and the MR imaging. This bioinspired strategy shows great potential for precise therapy/diagnosis of various tumors merely by adjusting the cell membrane source accordingly on the nanoparticle surface.


Asunto(s)
Membrana Celular/química , Sistemas de Liberación de Medicamentos , Nanopartículas , Animales , Línea Celular Tumoral , Doxorrubicina/administración & dosificación , Doxorrubicina/química , Compuestos Férricos/química , Humanos , Imagen por Resonancia Magnética , Magnetismo , Ratones , Neoplasias/tratamiento farmacológico
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