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1.
BMC Microbiol ; 23(1): 207, 2023 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-37528354

RESUMEN

BACKGROUND: The emergence of antibiotic resistance in pathogenic bacteria has become a global threat, encouraging the adoption of efficient and effective alternatives to conventional antibiotics and promoting their use as replacements. Titanium dioxide nanoparticles (TiO2 NPs) have been reported to exhibit antibacterial properties. In this study, we synthesized and characterized TiO2 NPs in anatase and rutile forms with surface modification by geraniol (GER). RESULTS: The crystallinity and morphology of modified TiO2 NPs were analyzed by UV/Vis spectrophotometry, X-ray powder diffraction (XRD), and scanning electron microscopy (SEM) with elemental mapping (EDS). The antimicrobial activity of TiO2 NPs with geraniol was assessed against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), and Escherichia coli. The minimum inhibitory concentration (MIC) values of modified NPs ranged from 0.25 to 1.0 mg/ml against all bacterial strains, and the live dead assay and fractional inhibitory concentration (FIC) supported the antibacterial properties of TiO2 NPs with GER. Moreover, TiO2 NPs with GER also showed a significant decrease in the biofilm thickness of MRSA. CONCLUSIONS: Our results suggest that TiO2 NPs with GER offer a promising alternative to antibiotics, particularly for controlling antibiotic-resistant strains. The surface modification of TiO2 NPs by geraniol resulted in enhanced antibacterial properties against multiple bacterial strains, including antibiotic-resistant MRSA. The potential applications of modified TiO2 NPs in the biomedical and environmental fields warrant further investigation.


Asunto(s)
Nanopartículas del Metal , Staphylococcus aureus Resistente a Meticilina , Nanopartículas , Antibacterianos/farmacología , Bacterias , Pruebas de Sensibilidad Microbiana
2.
BMC Microbiol ; 23(1): 288, 2023 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-37803300

RESUMEN

OBJECTIVES: Resistance to antibiotics among bacteria of clinical importance, including Staphylococcus aureus, is a serious problem worldwide and the search for alternatives is needed. Some metal complexes have antibacterial properties and when combined with antibiotics, they may increase bacterial sensitivity to antimicrobials. In this study, we synthesized the iron complex and tested it in combination with ampicillin (Fe16 + AMP) against S. aureus. METHODS: An iron complex (Fe16) was synthesized and characterized using spectroscopy methods. Confirmation of the synergistic effect between the iron complex (Fe16) and ampicillin (AMP) was performed using ζ-potential, infrared spectra and FICI index calculated from the minimum inhibitory concentration (MIC) from the checkerboard assay. Cytotoxic properties of combination Fe16 + AMP was evaluated on eukaryotic cell line. Impact of combination Fe16 + AMP on chosen genes of S. aureus were performed by Quantitative Real-Time PCR. RESULTS: The MIC of Fe16 + AMP was significantly lower than that of AMP and Fe16 alone. Furthermore, the infrared spectroscopy revealed the change in the ζ-potential of Fe16 + AMP. We demonstrated the ability of Fe16 + AMP to disrupt the bacterial membrane of S. aureus and that likely allowed for better absorption of AMP. In addition, the change in gene expression of bacterial efflux pumps at the sub-inhibitory concentration of AMP suggests an insufficient import of iron into the bacterial cell. At the same time, Fe16 + AMP did not have any cytotoxic effects on keratinocytes. CONCLUSIONS: Combined Fe16 + AMP therapy demonstrated significant synergistic and antimicrobial effects against S. aureus. This study supports the potential of combination therapy and further research.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Humanos , Staphylococcus aureus , Ampicilina/farmacología , Sinergismo Farmacológico , Antibacterianos/farmacología , Infecciones Estafilocócicas/tratamiento farmacológico , Pruebas de Sensibilidad Microbiana
3.
Molecules ; 28(3)2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36771123

RESUMEN

Complexes of carboxylic acids are very often studied due to their interesting structural, spectral, and magnetic properties. This review is focused on complexes of four dicarboxylic acids, namely, 2,2'-thiodioacetic, 3,3'-thiodipropionic, 3,3'-dithiodipropionic, and fumaric acid. Many of the complexes were characterized by single crystal X-ray analyses. Without the analyses, it is very difficult to predict the coordination mode of carboxylate groups or nitrogen ligands on central atoms. Thus, structural properties are also discussed, as well as potential applications.

4.
Inorg Chem ; 61(48): 19261-19273, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36383699

RESUMEN

Novel heteronuclear IrIII-CuII coordination compounds ([Ir(η5-Cp*)Cl2Pcfx-Cu(phen)](NO3)·1.75(CH3OH)·0.75(H2O) (1), [Ir(η5-Cp*)Cl2Pnfx-Cu(phen)](NO3)·1.75(CH3OH)·0.75(H2O) (2), [Ir(η5-Cp*)Cl2Plfx-Cu(phen)](NO3)·1.3(H2O)·1.95(CH3OH) (3), [Ir(η5-Cp*)Cl2Psfx-Cu(phen)] (4)) bearing phosphines derived from fluoroquinolones, namely, sparfloxacin (Hsfx), ciprofloxacin (Hcfx), lomefloxacin (Hlfx), and norfloxacin (Hnfx), have been synthesized and studied as possible anticancer chemotherapeutics. All compounds have been characterized by electrospray ionization mass spectrometry (ESI-MS), a number of spectroscopic methods (i.e., IR, fluorescence, and electron paramagnetic resonance (EPR)), cyclic voltammetry, variable-temperature magnetic susceptibility measurements, and X-ray diffractometry. The coordination geometry of IrIII in all complexes adopts a characteristic piano-stool geometry with the η5-coordinated and three additional sites occupied by two chloride and phosphine ligands, while CuII ions in complexes 1 and 2 form a distorted square-pyramidal coordination geometry, and in complex 3, the coordination geometry around CuII ions is a distorted octahedron. Interestingly, the crystal structure of [Ir(η5-Cp*)Cl2Plfx-Cu(phen)] features the one-dimensional (1D) metal-organic polymer. Liposomes loaded with redox-active and fluorescent [Ir(η5-Cp*)Cl2Pcfx-Cu(phen)] (1L) have been prepared to increase water solubility and minimize serious systemic side effects. It has been proven, by confocal microscopy and an inductively coupled plasma mass spectrometry (ICP-MS) analysis, that the liposomal form of compound 1 can be effectively accumulated inside human lung adenocarcinoma and human prostate carcinoma cells with selective localization in nuclei. A cytometric analysis showed dominance of apoptosis over the other cell death types. Furthermore, the investigated nanoformulations induced changes in the cell cycle, leading to S phase arrest in a dose-dependent manner. Importantly, in vitro anticancer action on three-dimensional (3D) multicellular tumor spheroids has been demonstrated.


Asunto(s)
Carcinoma , Complejos de Coordinación , Humanos , Masculino , Cobre/química , Liposomas , Próstata , Iones , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Cristalografía por Rayos X
5.
J Nanobiotechnology ; 19(1): 103, 2021 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-33849566

RESUMEN

In a biological system, nanoparticles (NPs) may interact with biomolecules. Specifically, the adsorption of proteins on the nanoparticle surface may influence both the nanoparticles' and proteins' overall bio-reactivity. Nevertheless, our knowledge of the biocompatibility and risk of exposure to nanomaterials is limited. Here, in vitro and ex ovo biocompatibility of naturally based crosslinked freeze-dried 3D porous collagen/chitosan scaffolds, modified with thermostable fibroblast growth factor 2 (FGF2-STAB®), to enhance healing and selenium nanoparticles (SeNPs) to provide antibacterial activity, were evaluated. Biocompatibility and cytotoxicity were tested in vitro using normal human dermal fibroblasts (NHDF) with scaffolds and SeNPs and FGF2-STAB® solutions. Metabolic activity assays indicated an antagonistic effect of SeNPs and FGF2-STAB® at high concentrations of SeNPs. The half-maximal inhibitory concentration (IC50) of SeNPs for NHDF was 18.9 µg/ml and IC80 was 5.6 µg/ml. The angiogenic properties of the scaffolds were monitored ex ovo using a chick chorioallantoic membrane (CAM) assay and the cytotoxicity of SeNPs over IC80 value was confirmed. Furthermore, the positive effect of FGF2-STAB® at very low concentrations (0.01 µg/ml) on NHDF metabolic activity was observed. Based on detailed in vitro testing, the optimal concentrations of additives in the scaffolds were determined, specifically 1 µg/ml of FGF2-STAB® and 1 µg/ml of SeNPs. The scaffolds were further subjected to antimicrobial tests, where an increase in selenium concentration in the collagen/chitosan scaffolds increased the antibacterial activity. This work highlights the antimicrobial ability and biocompatibility of newly developed crosslinked collagen/chitosan scaffolds involving FGF2-STAB® and SeNPs. Moreover, we suggest that these sponges could be used as scaffolds for growing cells in systems with low mechanical loading in tissue engineering, especially in dermis replacement, where neovascularization is a crucial parameter for successful skin regeneration. Due to their antimicrobial properties, these scaffolds are also highly promising for tissue replacement requiring the prevention of infection.


Asunto(s)
Materiales Biocompatibles/farmacología , Quitosano/farmacología , Colágeno/farmacología , Factor 2 de Crecimiento de Fibroblastos/farmacología , Nanopartículas/química , Nanopartículas/uso terapéutico , Selenio/farmacología , Andamios del Tejido , Animales , Antibacterianos , Línea Celular , Fibroblastos/efectos de los fármacos , Humanos , Ensayo de Materiales , Porosidad , Selenio/química , Ingeniería de Tejidos/métodos , Cicatrización de Heridas
6.
Biomacromolecules ; 21(2): 418-434, 2020 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-31738540

RESUMEN

Minimization of drug side effects is a hallmark of advanced targeted therapy. Herein we describe the synthesis of polysaccharide-based nanocapsules prepared from furcellaran and chitosan via layer-by-layer deposition using electrostatic interaction. Using doxorubicin as a model drug, prepared nanocapsules showed excellent drug loading properties and release influence by pH and stability. Targeted delivery of doxorubicin was achieved by nanocapsule surface modification using homing peptide (seq SMSIARLC). The synthesized nanocapsules possess excellent compatibility to eukaryotic organisms. In the case of nonmalignant cells (PNT1A and HEK-293), toxicity tests revealed the absences of DNA fragmentation, apoptosis, necrosis, and also disruption of erythrocyte membranes. In contrast, results from treatment of malignant cell lines (MDA-MB-231 and PC3) indicate good anticancer effects of synthesized bionanomaterial. Internalization studies revealed the nanocapsule's ability to enter the malignant cell lines by endocytosis and triggering the apoptosis. The occurrence of apoptosis is mostly connected to the presence of ROS and inability of DNA damage reparation. Additionally, the obtained results strongly indicate that peptide modification increases the speed of nanocapsule internalization into malignant cell lines while simultaneously nonmalignant cell lines are untouched by nanocapsules highlighting the strong selectivity of the peptide.


Asunto(s)
Preparaciones de Acción Retardada , Doxorrubicina/farmacocinética , Nanocápsulas/química , Alginatos/química , Línea Celular Tumoral , Quitosano/química , Doxorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos , Femenino , Células HEK293 , Hemólisis/efectos de los fármacos , Humanos , Concentración de Iones de Hidrógeno , Persona de Mediana Edad , Nanocápsulas/administración & dosificación , Nanocápsulas/toxicidad , Péptidos/química , Péptidos/metabolismo , Gomas de Plantas/química , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Polielectrolitos/química , Pruebas de Toxicidad
7.
Int J Mol Sci ; 21(7)2020 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-32290291

RESUMEN

The current epidemic of antibiotic-resistant infections urges to develop alternatives to less-effective antibiotics. To assess anti-bacterial potential, a novel coordinate compound (RU-S4) was synthesized using ruthenium-Schiff base-benzimidazole ligand, where ruthenium chloride was used as the central atom. RU-S4 was characterized by scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), and Raman spectroscopy. Antibacterial effect of RU-S4 was studied against Staphylococcus aureus (NCTC 8511), vancomycin-resistant Staphylococcus aureus (VRSA) (CCM 1767), methicillin-resistant Staphylococcus aureus (MRSA) (ST239: SCCmecIIIA), and hospital isolate Staphylococcus epidermidis. The antibacterial activity of RU-S4 was checked by growth curve analysis and the outcome was supported by optical microscopy imaging and fluorescence LIVE/DEAD cell imaging. In vivo (balb/c mice) infection model prepared with VRSA (CCM 1767) and treated with RU-S4. In our experimental conditions, all infected mice were cured. The interaction of coordination compound with bacterial cells were further confirmed by cryo-scanning electron microscope (Cryo-SEM). RU-S4 was completely non-toxic against mammalian cells and in mice and subsequently treated with synthesized RU-S4.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Rutenio/química , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Espectrometría Raman
8.
Bull Environ Contam Toxicol ; 105(2): 244-249, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32556691

RESUMEN

The aim of the study was to assess the effects of silver nanoparticles (AgNPs1 = 2.7 d·nm, AgNPs2 = 6.5 d·nm) and silver nitrate (AgNO3) on Enchytraeus crypticus and Folsomia candida using toxicity tests (OECD Guideline 220, 232). A 28-day chronic toxicity study was performed to evaluate the reproduction and mortality rate. E. crypticus reproduction was more sensitive to AgNO3 with a 28dEC50 of 86.40 (62.52-119.4) mg·kg-1 dry weight (d.w.) compared to AgNPs1 (28dEC50 = 119.3 (60.4-235.6) mg·kg-1 d.w). Similarly, the reproduction of F. candida was inhibited the most by AgNO3 with a 28dEC50 of 126.2 (104.2-152.9) mg·kg-1 d.w. followed by AgNPs1 (28dEC50 = 158.7 (64.05-393.2) mg·kg-1 d.w.) and AgNPs2 (28dEC50 = 206.4 (181.9-234.1) mg·kg-1 d.w.). No mortalities were observed for tested soil invertebrates exposed to AgNPs at concentrations up to 166 mg·kg-1 d.w. of AgNPs1 and 300 mg·kg-1 d.w. of AgNPs2, respectively. It was found that silver ions are more toxic in comparison with AgNPs.


Asunto(s)
Artrópodos/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Oligoquetos/efectos de los fármacos , Nitrato de Plata/toxicidad , Plata/toxicidad , Contaminantes del Suelo/toxicidad , Animales , Iones , Nanopartículas del Metal/química , Reproducción/efectos de los fármacos , Plata/química , Suelo/química , Suelo/normas , Contaminantes del Suelo/química , Pruebas de Toxicidad Crónica
9.
Bull Environ Contam Toxicol ; 105(4): 530-537, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32940716

RESUMEN

An increase in the production and usage of gold nanoparticles (AuNPs) triggers the necessity to focus on their impact on ecosystems. Therefore, the purpose of this study was to investigate the acute toxicity of AuNPs and ionic gold (Au (III)) to organisms representing all trophic levels of the aquatic ecosystem, namely producers (duckweed Lemna minor), consumers (crustacean Daphnia magna, embryos of Danio rerio) and decomposers (bacteria Vibrio fischeri). The organisms were exposed according to a standardized protocol for each species and endpoints. The AuNPs (1.16 and 11.6 d.nm) were synthesized using citrate (CIT) and polyvinylpyrrolidone (PVP) as capping agents, respectively. It was found, that Au (III) was significantly more toxic than AuNPs PVP and AuNPs CIT. AuNPs showed significant toxicity only at high concentrations (mg/L), which are not environmentally relevant in the present time, but a cautious approach is advised, due to the possibility of interactions with other contaminants.


Asunto(s)
Aliivibrio fischeri/efectos de los fármacos , Araceae/efectos de los fármacos , Daphnia/efectos de los fármacos , Oro/toxicidad , Iones/toxicidad , Nanopartículas del Metal/toxicidad , Pez Cebra , Animales , Organismos Acuáticos , Daphnia/embriología , Relación Dosis-Respuesta a Droga , Embrión no Mamífero/efectos de los fármacos , Pruebas de Toxicidad Aguda
10.
Neuro Endocrinol Lett ; 39(6): 465-472, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30796797

RESUMEN

OBJECTIVES: The aim of this study was to clarify the influence of three different sizes of platinum nanoparticles on aquatic ecosystem and assess the toxic effect in term of particle size. Tests were conducted on organisms representing all trophic levels of the aquatic ecosystem, namely producers (duckweed Lemna minor), consumers (water fleas Daphnia magna) and decomposers (bacteria Vibrio fischeri). DESIGN: Experiments were carried out methodologically in accordance with the following standards: OECD 221 guideline (Lemna sp. Growth Inhibition test), OECD 202 guideline (Inhibition of the mobility of Daphnia magna) and ISO 11348-2 (Inhibitory effect of platinum nanoparticles on the light emission of Vibrio fischeri). RESULTS: The most toxic have been the smallest sized platinum nanoparticles for all tested organisms. The highest toxicity of all tested samples (Pt1, Pt2, Pt3) was observed in bacteria (30´EC50 = 135.47; 167.94; 254.64 µg.L-1), respectively. The lowest toxicity was recorded for Daphnia (48hEC50 = 405.74; 413.24; 514.07 µg.L-1), respectively. CONCLUSION: The ecotoxicity of platinum nanoparticles varies considerably according to the test organisms and particle size.


Asunto(s)
Nanopartículas del Metal/toxicidad , Platino (Metal)/toxicidad , Aliivibrio fischeri , Animales , Biota , Daphnia , Relación Dosis-Respuesta a Droga , Nanopartículas del Metal/química , Platino (Metal)/química , Contaminantes del Agua/toxicidad
11.
Bioconjug Chem ; 29(9): 2954-2969, 2018 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-30086240

RESUMEN

Novicidin (NVC), is a membrane-penetrating peptide, which forms a stable complex with Zn-Schiff base with interesting antitumor selectivity. We studied NVC derivatives to determine functional roles of key amino acids in toxicity, helicity, and binding of the Zn-Schiff base complex. Trimmed derivatives highlighted the role of peptide length and helicity in toxicity and membrane penetration. The removal of Lys from position 1 and 2 strongly increases the ability to disrupt the membranes. The trimming of the N-terminal residues significantly increases the stability of peptide helicity enhancing penetrating properties. Gly residue derivatives undermined a role of peptide bending in membrane penetration and toxicity. After the substitution of the central Gly derivatives with Ile or Lys, the peptides retained toxicity. These results illustrate the minor role of central helix bending in NVC toxicity. Binding-site-peptide derivatives identified His residue as the sole Zn-Schiff base binding site and eliminated the role of other aromatic residues.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/administración & dosificación , Sistemas de Liberación de Medicamentos , Bases de Schiff/química , Zinc/administración & dosificación , Secuencia de Aminoácidos , Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/toxicidad , Sitios de Unión , Línea Celular Tumoral , Permeabilidad de la Membrana Celular , Glicina/química , Humanos , Ligandos , Conformación Proteica , Espectroscopía de Protones por Resonancia Magnética , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectroscopía Infrarroja por Transformada de Fourier , Zinc/química
12.
Mol Pharm ; 14(1): 221-233, 2017 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-27943679

RESUMEN

Herein we describe a novel alternative synthesis route of polyvinylpyrrolidone nanoparticles using salting-out method at a temperature close to polyvinylpyrrolidone decomposition. At elevated temperatures, the stability of polyvinylpyrrolidone decreases and the opening of pyrrolidone ring fractions occurs. This leads to cross-linking process, where separate units of polyvinylpyrrolidone interact among themselves and rearrange to form nanoparticles. The formation/stability of these nanoparticles was confirmed by transmission electron microscopy, X-ray photoelectron spectroscopy, mass spectrometry, infrared spectroscopy, and spectrophotometry. The obtained nanoparticles possess exceptional biocompatibility. No toxicity and genotoxicity was found in normal human prostate epithelium cells (PNT1A) together with their high hemocompatibility. The antimicrobial effects of polyvinylpyrrolidone nanoparticles were tested on bacterial strains isolated from the wounds of patients suffering from hard-to-heal infections. Molecular analysis (qPCR) confirmed that the treatment can induce the regulation of stress-related survival genes. Our results strongly suggest that the polyvinylpyrrolidone nanoparticles have great potential to be developed into a novel antibacterial compound.


Asunto(s)
Antibacterianos/química , Materiales Biocompatibles/química , Nanopartículas/química , Povidona/química , Antibacterianos/farmacología , Materiales Biocompatibles/farmacología , Línea Celular , Estabilidad de Medicamentos , Epitelio/efectos de los fármacos , Humanos , Masculino , Pruebas de Sensibilidad Microbiana/métodos , Microscopía Electrónica de Transmisión/métodos , Espectroscopía de Fotoelectrones/métodos , Próstata/efectos de los fármacos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Difracción de Rayos X/métodos
13.
Sensors (Basel) ; 17(4)2017 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-28338634

RESUMEN

Magnetic particles (MPs) have been widely used in biological applications in recent years as a carrier for various molecules. Their big advantage is in repeated use of immobilized molecules including enzymes. Acetylcholinesterase (AChE) is an enzyme playing crucial role in neurotransmission and the enzyme is targeted by various molecules like Alzheimer's drugs, pesticides and warfare agents. In this work, an electrochemical biosensor having AChE immobilized onto MPs and stabilized through glutaraldehyde (GA) molecule was proposed for assay of the neurotoxic compounds. The prepared nanoparticles were modified by pure AChE and they were used for the measurement anti-Alzheimer's drug galantamine and carbamate pesticide carbofuran with limit of detection 1.5 µM and 20 nM, respectively. All measurements were carried out using screen-printed sensor with carbon working, silver reference, and carbon auxiliary electrode. Standard Ellman's assay was used for validation measurement of both inhibitors. Part of this work was the elimination of reversible inhibitors represented by galantamine from the active site of AChE. For this purpose, we used a lower pH to get the original activity of AChE after inhibition by galantamine. We also observed decarbamylation of the AChE-carbofuran adduct. Influence of organic solvents to AChE as well as repeatability of measurement with MPs with AChE was also established.


Asunto(s)
Nanopartículas , Acetilcolinesterasa , Técnicas Biosensibles , Inhibidores de la Colinesterasa , Enzimas Inmovilizadas , Compuestos Organofosforados , Plaguicidas
14.
Electrophoresis ; 37(3): 444-54, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26462605

RESUMEN

Peptide-peptide interactions are crucial in the living cell as they lead to the formation of the numerous types of complexes. In this study, synthetic peptides containing 11 of cysteines (α-domain of metallothionein (MT)) and sialic acid binding region (130-loop of hemagglutinin (HA)) were employed. The aim of the experiment was studying the interactions between MT and HA-derived peptides. For this purpose, fragments were tagged with cysteines at C-terminal part to serve as ligand sites for PbS and CuS quantum dots (QDs), and therefore these conjugates can be traced and quantified during wide spectrum of methods. As a platform for interaction, γ-Fe2O3 paramagnetic particles modified with tetraethyl orthosilicate and (3-aminopropyl)triethoxysilane (hydrodynamic diameter 30-40 nm) were utilized and MT/HA interactions were examined using multi-instrumental approach including electrochemistry, electrophoretic methods, and MALDI-TOF/TOF mass spectrometry. It was found that peptides enter mutual creation of complexes, which are based on some of nonbonded interactions. The higher willingness to interact was observed in MT-derived peptides toward immobilized HA. Finally, we designed and manufactured flow-through electrochemical 3D printed device (reservoir volume 150 µL) and utilized it for automated analysis of the HA/MT metal labels. Under the optimal conditions, (deposition time and flow rate 80 s and 1.6 mL/min for CuS and 120 s and 1.6 mL/min PbS, respectively), the results of peptide-conjugated QDs were comparable with atomic absorption spectrometry.


Asunto(s)
Nanopartículas de Magnetita/química , Técnicas Analíticas Microfluídicas/instrumentación , Péptidos/análisis , Péptidos/metabolismo , Impresión Tridimensional , Péptidos/química , Unión Proteica
15.
Electrophoresis ; 37(14): 2025-35, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27130152

RESUMEN

Annual epidemics of influenza cause death of hundreds of thousands people and they also have a significant economic impact. Hence, a need for fast and cheap influenza diagnostic method is arising. The conventional methods for an isolation of the viruses are time-consuming and require expensive instrumentation as well as trained personnel. In this study, we modified the surface of nanomaghemite (γ-Fe2 O3 ) paramagnetic core with tetraethyl orthosilicate and (3-aminopropyl)triethoxysilane and the resulting particles were utilized for the isolation of H7N7 influenza virions. Consequently, we designed γ-Fe2 O3 paramagnetic core modified with calcium tripolyphosphate which was employed for the isolation of viral nucleic acid after virion's lysis. Both of these procedures can be performed rapidly in less than 10 min and, in combination with the RT-PCR, the whole influenza detection can be shortened to few hours. Moreover, the whole protocol could be easily automated and/or miniaturized, and thus can serve as a basis for use in a lab-on-a-chip device. We assume that magnetic isolation is an exceptional procedure which can significantly accelerate the diagnostic possibilities of a broad spectrum of diseases.


Asunto(s)
Subtipo H7N7 del Virus de la Influenza A/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Virión/aislamiento & purificación , Animales , Embrión de Pollo , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Transcripción Reversa
17.
Analyst ; 141(9): 2665-75, 2016 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-26882954

RESUMEN

In this study, enhancement of the electrochemical signals of etoposide (ETO) measured by differential pulse voltammetry (DPV) by modifying a glassy carbon electrode (GCE) with carbon quantum dots (CQDs) is demonstrated. In comparison with a bare GCE, the modified GCE exhibited a higher sensitivity towards electrochemical detection of ETO. The lowest limit of detection was observed to be 5 nM ETO. Furthermore, scanning electron microscopy (SEM), fluorescence microscopy (FM), and electrochemical impedance spectroscopy (EIS) were employed for the further study of the working electrode surface after the modification with CQDs. Finally, the GCE modified with CQDs under optimized conditions was used to analyse real samples of ETO in the prostate cancer cell line PC3. After different incubation times (1, 3, 6, 9, 12, 18 and 24 h), these samples were then prepared prior to electrochemical detection by the GCE modified with CQDs. High performance liquid chromatography with an electrochemical detection method was employed to verify the results from the GCE modified with CQDs.


Asunto(s)
Carbono/química , Electroquímica/métodos , Etopósido/análisis , Vidrio/química , Puntos Cuánticos/química , Línea Celular Tumoral , Electroquímica/instrumentación , Electrodos , Etopósido/química , Etopósido/farmacología , Humanos , Límite de Detección , Povidona/química
18.
Environ Res ; 151: 233-243, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27504871

RESUMEN

The interaction of a plethora nanoparticles with major biota such as plants and animals/humans has been the subject of various multidisciplinary studies with special emphasis on toxicity aspects. However, reports are meager on the transport phenomena of nanoparticles in the plant-animal/human system. Since plants and animals/humans are closely linked via food chain, discussion is imperative on the main processes and mechanisms underlying the transport phenomena of nanoparticles in the plant-animal/human system, which is the main objective of this paper. Based on the literature appraised herein, it is recommended to perform an exhaustive exploration of so far least explored aspects such as reproducibility, predictability, and compliance risks of nanoparticles, and insights into underlying mechanisms in context with their transport phenomenon in the plant-animal/human system. The outcomes of the suggested studies can provide important clues for fetching significant benefits of rapidly expanding nanotechnology to the plant-animal/human health-improvements and protection as well.


Asunto(s)
Nanopartículas/metabolismo , Plantas/metabolismo , Animales , Transporte Biológico , Cadena Alimentaria , Humanos
19.
Sensors (Basel) ; 16(3): 290, 2016 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-26927112

RESUMEN

Liposome-based drug delivery systems hold great potential for cancer therapy. The aim of this study was to design a nanodevice for targeted anchoring of liposomes (with and without cholesterol) with encapsulated anticancer drugs and antisense N-myc gene oligonucleotide attached to its surface. To meet this main aim, liposomes with encapsulated doxorubicin, ellipticine and etoposide were prepared. They were further characterized by measuring their fluorescence intensity, whereas the encapsulation efficiency was estimated to be 16%. The hybridization process of individual oligonucleotides forming the nanoconstruct was investigated spectrophotometrically and electrochemically. The concentrations of ellipticine, doxorubicin and etoposide attached to the nanoconstruct in gold nanoparticle-modified liposomes were found to be 14, 5 and 2 µg·mL(-1), respectively. The study succeeded in demonstrating that liposomes are suitable for the transport of anticancer drugs and the antisense oligonucleotide, which can block the expression of the N-myc gene.


Asunto(s)
ADN sin Sentido/uso terapéutico , Sistemas de Liberación de Medicamentos , Nanopartículas de Magnetita/química , Neoplasias/tratamiento farmacológico , ADN sin Sentido/química , Doxorrubicina/química , Doxorrubicina/uso terapéutico , Elipticinas/química , Elipticinas/uso terapéutico , Etopósido/química , Etopósido/uso terapéutico , Fluorescencia , Oro/química , Humanos , Liposomas/química , Liposomas/uso terapéutico , Nanopartículas de Magnetita/uso terapéutico , Proteína Proto-Oncogénica N-Myc/antagonistas & inhibidores , Proteína Proto-Oncogénica N-Myc/genética
20.
Int J Mol Sci ; 17(4)2016 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-27104527

RESUMEN

Magnetic isolation of biological targets is in major demand in the biotechnology industry today. This study considers the interaction of four surface-modified magnetic micro- and nanoparticles with selected DNA fragments. Different surface modifications of nanomaghemite precursors were investigated: MAN37 (silica-coated), MAN127 (polyvinylpyrrolidone-coated), MAN158 (phosphate-coated), and MAN164 (tripolyphosphate-coated). All particles were positive polycharged agglomerated monodispersed systems. Mean particle sizes were 0.48, 2.97, 2.93, and 3.67 µm for MAN37, MAN127, MAN164, and MAN158, respectively. DNA fragments exhibited negative zeta potential of -0.22 mV under binding conditions (high ionic strength, low pH, and dehydration). A decrease in zeta potential of particles upon exposure to DNA was observed with exception of MAN158 particles. The measured particle size of MAN164 particles increased by nearly twofold upon exposure to DNA. Quantitative PCR isolation of DNA with a high retrieval rate was observed by magnetic particles MAN127 and MAN164. Interaction between polycharged magnetic particles and DNA is mediated by various binding mechanisms such as hydrophobic and electrostatic interactions. Future development of DNA isolation technology requires an understanding of the physical and biochemical conditions of this process.


Asunto(s)
ADN/aislamiento & purificación , Magnetismo/métodos , Biotecnología/métodos , ADN/química , Microscopía Electrónica de Rastreo , Nanopartículas/química , Nanopartículas/ultraestructura , Tamaño de la Partícula , Reacción en Cadena en Tiempo Real de la Polimerasa
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