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1.
Front Immunol ; 13: 843684, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651617

RESUMO

Background: Candida albicans infections are particularly prevalent in immunocompromised patients. Even with appropriate treatment with current antifungal drugs, the mortality rate of invasive candidiasis remains high. Many positive results have been achieved in the current vaccine development. There are also issues such as the vaccine's protective effect is not persistent. Considering the functionality and cost of the vaccine, it is important to develop safe and efficient new vaccines with long-term effects. In this paper, an antifungal nanovaccine with Polyethyleneimine (PEI) as adjuvant was constructed, which could elicit more effective and long-term immunity via stimulating B cells to differentiate into long-lived plasma cells. Materials and Methods: Hsp90-CTD is an important target for protective antibodies during disseminated candidiasis. Hsp90-CTD was used as the antigen, then introduced SDS to "charge" the protein and added PEI to form the nanovaccine. Dynamic light scattering and transmission electron microscope were conducted to identify the size distribution, zeta potential, and morphology of nanovaccine. The antibody titers in mice immunized with the nanovaccine were measured by ELISA. The activation and maturation of long-lived plasma cells in bone marrow by nanovaccine were also investigated via flow cytometry. Finally, the kidney of mice infected with Candida albicans was stained with H&E and PAS to evaluate the protective effect of antibody in serum produced by immunized mice. Results: Nanoparticles (NP) formed by Hsp90-CTD and PEI are small, uniform, and stable. NP had an average size of 116.2 nm with a PDI of 0.13. After immunizing mice with the nanovaccine, it was found that the nano-group produced antibodies faster and for a longer time. After 12 months of immunization, mice still had high and low levels of antibodies in their bodies. Results showed that the nanovaccine could promote the differentiation of B cells into long-lived plasma cells and maintain the long-term existence of antibodies in vivo. After immunization, the antibodies in mice could protect the mice infected by C. albicans. Conclusion: As an adjuvant, PEI can promote the differentiation of B cells into long-lived plasma cells to maintain long-term antibodies in vivo. This strategy can be adapted for the future design of vaccines.


Assuntos
Polietilenoimina , Vacinas , Adjuvantes Imunológicos , Adjuvantes Farmacêuticos , Animais , Antifúngicos/farmacologia , Candida albicans , Candidíase , Humanos , Camundongos
2.
J Hazard Mater ; 436: 129270, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35739785

RESUMO

Chromium (VI) is a widely occurring toxic heavy metal ion in industrial wastewater that seriously impacts the environment. In this study, we used environmentally friendly sodium lignosulfonate (SL), polyethyleneimine (PEI), and sodium alginate (SA) to synthesize SL/PEI/SA beads by employing a simple crosslinking method with to develop a novel absorbent with excellent adsorption capacity and practical application in wastewater treatment. We studied the adsorption performance of SL/PEI/SA through batch adsorption and continuous dynamic adsorption experiments. SL/PEI/SA has ultra-high adsorption capacity (2500 mg·g-1) at 25 â„ƒ, which is much higher than that of existing adsorbents. Humic acids and coexisting anions commonly found in wastewater have minimal effect on the adsorption performance of SL/PEI/SA. In the column system, 1 g SL/PEI/SA can treat 8.1 L secondary electroplating wastewater at a flow rate of 0.5 mLmin-1, thereby enabling the concentration of Cr(VI) in secondary electroplating wastewater to meet the discharge standard (< 0.2 mg·L-1). It is worth noting that the concentration of competitive ions in secondary electroplating wastewater is more than 500 times higher than that of Cr(VI). These results demonstrate that the novel SL/PEI/SA beads can be effectively applied in the removal of Cr(VI) in wastewater.


Assuntos
Polietilenoimina , Poluentes Químicos da Água , Adsorção , Alginatos , Cromo , Concentração de Íons de Hidrogênio , Cinética , Lignina/análogos & derivados , Sódio , Águas Residuárias , Água
3.
Biosensors (Basel) ; 12(6)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35735566

RESUMO

Hydroxyapatite (HAP) materials are widely applied as biomedical materials due to their stable performance, low cost, good biocompatibility and biodegradability. Here, a green, fast and efficient strategy was designed to construct a fluorescent nanosystem for cell imaging and drug delivery based on polyethyleneimine (PEI) and functionalized HAP via simple physical adsorption. First, HAP nanorods were functionalized with riboflavin sodium phosphate (HE) to provide them with fluorescence properties based on ligand-exchange process. Next, PEI was attached on the surface of HE-functionalized HAP (HAP-HE@PEI) via electrostatic attraction. The fluorescent HAP-HE@PEI nanosystem could be rapidly taken up by NIH-3T3 fibroblast cells and successfully applied to for cell imaging. Additionally, doxorubicin hydrochloride (DOX) containing HAP-HE@PEI with high loading capacity was prepared, and in-vitro release results show that the maximum release of DOX at pH 5.4 (31.83%) was significantly higher than that at pH 7.2 (9.90%), which can be used as a drug delivery tool for cancer therapy. Finally, HAP-HE@PEI as the 3D inkjet printing ink were printed with GelMA hydrogel, showing a great biocompatible property for 3D cell culture of RAW 264.7 macrophage cells. Altogether, because of the enhanced affinity with the cell membrane of HAP-HE@PEI, this green, fast and efficient strategy may provide a prospective candidate for bio-imaging, drug delivery and bio-printing.


Assuntos
Nanotubos , Neoplasias , Doxorrubicina , Sistemas de Liberação de Medicamentos/métodos , Durapatita/química , Nanotubos/química , Polietilenoimina , Estudos Prospectivos
4.
J Environ Manage ; 317: 115400, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35653848

RESUMO

A cryogel solid amine adsorbent with a laminated structure has been prepared by crosslinking polyethylenimine (PEI) with ethylene glycol diglycidyl ether (EGDE) at a low temperature via liquid nitrogen treatment and freeze-drying. The effects of cryogenic treatment on the morphology of the cryogels were investigated. The liquid nitrogen treatment and freeze drying were critical to create the layered structure. The fast formation of ice crystals at 77 K served as a template which directed the ordered lamellar structure of the PEI and EGDE cross-linked polymer networks. The PEI cryogel adsorbent showed excellent CO2 adsorption performance both in dry and wet conditions. In dry conditions, the PEI-gel-5-0.25 cryogel showed a 5.60 mmol/g of CO2 adsorption capacity at 75 °C. After being swelled with water, the PEI-gel-15-0.25 cryogel showed an extremely high CO2 adsorption capacity of 11.39 mmol/g at 25 °C. The adsorption behaviors of adsorbents with varied water contents were explained using kinetic simulations and intraparticle diffusion simulations. It was found that the presence of water can significantly enhance the diffusion process. The regeneration performance was examined in both dry and wet conditions. After 20 adsorption-desorption cycles, the adsorption capacity of the regenerated PEI cryogel had barely decreased, indicating reliable regeneration stability.


Assuntos
Criogéis , Polietilenoimina , Adsorção , Carbono , Dióxido de Carbono/química , Criogéis/química , Nitrogênio , Polietilenoimina/química , Água
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 279: 121466, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35696970

RESUMO

A novel polyethyleneimine (PEI)-based polymeric nanosensor (named PEIMP) was developed for specific fluorescence enhanced sensing of Pt4+ ion in aqueous media. The sensor was fabricated via "one-pot" three-component reaction using ortho-phthalaldehyde (OPA), PEI and mercaptopurine as raw materials, by which the formation of isoindole fluorophore and its chemical grafting onto PEI chain were achieved simultaneously. The morphology, size and structure of PEIMP have been characterized by various techniques. In buffered aqueous solution (pH 7.0), PEIMP had the ability to specifically bind with Pt4+ producing notable increase in fluorescence emission at 463 nm (excited at 395 nm). Based on investigations on the sensing mechanism, the fluorescence turn-on response towards Pt4+ was attributed to the binding of Pt4+ with purine group in PEIMP resulting in the inhibition of photoinduced electron transfer from purine to isoindole fluorophore. Under the optimal conditions (pH 7.0, incubated at 37 ℃ for 20 min) the detection of Pt4+ could be achieved with the linear range of 0.1-10 µM and the detection limit of 80 nM. The sensor had the advantages of low-cost raw materials, simple and environmental-friendly synthesis and analytical detection procedures. What's more, it could selectively and sensitively detect Pt4+ without the effects from common transition metal ions (Pb2+, Fe3+, Cr3+, Al3+, Ag+, Co2+, Hg2+, Cd2+, Cu2+, Mg2+, Ni2+, Mn2+, Zn2+), especially precious metalions of Pt2+ and Pd2+. The proposed method had been successfully applied to quantify Pt4+ in wastewater and urine samples, and also proved to be potential for monitoring Pt4+ in biological systems.


Assuntos
Corantes Fluorescentes , Polietilenoimina , Corantes Fluorescentes/química , Íons , Isoindóis , Polietilenoimina/química , Purinas , Espectrometria de Fluorescência
6.
Chemosphere ; 304: 135374, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35718027

RESUMO

Enzymatic membrane reactors equipped with multifunctional biocatalytic membranes are promising and sustainable alternatives for removal of micropollutants, including steroid estrogens, under mild conditions. Thus, in this study an effort was made to produce novel multifunctional biocatalytic polyelectrolyte multilayer membranes via polyelectrolyte layer-by-layer assembly with laccase enzyme immobilized between or into polyelectrolyte layers. In this study, multifunctional biocatalytic membranes are considered as systems composed of commercially available filtration membrane modified by polyelectrolytes and immobilized enzymes, which are produced for complex treatment of water pollutants. The multifunctionality of the proposed systems is related to the fact that these membranes are capable of micropollutants removal via simultaneous catalytic conversion, membrane adsorption and membrane rejection making remediation process more complex, however, also more efficient. Briefly, cationic poly-l-lysine and polyethylenimine as well as anionic poly(sodium 4-styrenesulfonate) polyelectrolytes were deposited onto NP010 nanofiltration and UFX5 ultrafiltration membranes to produce systems for removal of 17α-ethynylestradiol. Images from scanning electron microscopy confirm effective enzyme deposition, whereas results of zeta potential measurements indicate introduction of positive charge onto the membranes. Based on preliminary results, four membranes with over 70%, activity retention produced using polyethylenimine in internal and entrapped mode, were selected for degradation tests. Systems based on UFX5 membrane allowed over 60% 17α-ethynylestradiol removal within 100 min, whereas NP010-based systems removed over 75% of estrogen within 150 min. Further, around 80% removal of 17α-ethynylestradiol was possible from the solutions at concentration up to 0.1 mg/L at pH ranging from 4 to 6 and at the pressure up to 3 bar, indicating high activity of the immobilized laccase over wide range of process conditions. Produced systems exhibited also great long-term stability followed by limited enzyme elution from the membrane. Finally, removal of over 70% and 60% of 17α-ethynylestradiol, respectively by NP010 and UFX5 systems after 8 cycles of repeated use indicate high reusability potential of the systems and suggest their practical application in removal of micropollutants, including estrogens.


Assuntos
Lacase , Polietilenoimina , Enzimas Imobilizadas/metabolismo , Estrogênios , Etinilestradiol , Lacase/metabolismo , Preparações Farmacêuticas , Polieletrólitos
7.
J Vis Exp ; (183)2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35695542

RESUMO

The current protocol describes the use of lentiviral particles for the delivery of short hairpin RNAs (shRNAs) to both human embryonic stem cells (hESCs) as well as neural progenitor cells (NPCs) derived from hESCs at high efficiency. Lentiviral particles were generated by co-transfecting HEK293T cells using entry vectors (carrying shRNAs) along with packaging plasmids (pAX and pMD2.G) using the low-cost cationic polymer polyethylenimine (PEI). Viral particles were concentrated using ultracentrifugation, which resulted in average titers above 5 x 107. Both hESCs and NPCs could be infected at high efficiencies using these lentiviral particles, as shown by puromycin selection and stable expression in hESCs, as well as transient GFP expression in NPCs. Furthermore, western blot analysis showed a significant reduction in the expression of genes targeted by shRNAs. In addition, the cells retained their pluripotency as well as differentiation potential, as evidenced by their subsequent differentiation into different lineages of CNS. The current protocol deals with the delivery of shRNAs; however, the same approach could be used for the ectopic expression of cDNAs for overexpression studies.


Assuntos
Células-Tronco Embrionárias Humanas , Lentivirus , Vetores Genéticos , Células HEK293 , Humanos , Lentivirus/genética , Polietilenoimina , Polímeros , RNA Interferente Pequeno/genética
8.
ACS Macro Lett ; 11(6): 773-779, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35653775

RESUMO

The pH-regulated charge inversions on polyethylenimine (PEI)-coated surfaces are indispensable to their applications in biomaterials and nanomaterials. Various PEI-coated surfaces, where single charge inversion happens, have been extensively investigated, while the surfaces where double charge inversion appears are less reported. Here, using a molecular theory, we systematically study the pH-regulated charge density of PEI-coated surfaces. The results suggest whether single or double charge inversion happens depends on PEI affinity to the surface and the bare surface charge density. The region of double charge inversion is much smaller than that of single charge inversion, revealing the reason why double charge inversion is less observed in experiments. Besides, the charge inversions are significantly influenced by the solution condition. The present work provides a useful guideline to the selection of the coated materials and the parameters of PEI solution in the design of PEI-coated surfaces aiming to promote their applications in multifunctional nanomaterials.


Assuntos
Polietilenoimina , Concentração de Íons de Hidrogênio
9.
J Environ Manage ; 316: 115155, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35561490

RESUMO

Landfilling and burning plastic waste, especially waste polyvinyl chloride (PVC), can produce highly toxic and carcinogenic by-products that threaten the ecosystem and human health. However, there is still a lack of proper methods for waste PVC recycling. Therefore, developing feasible ways for waste PVC recovery is urgently needed. The purpose of this study is to analyze the characteristics of PVC-based adsorptive nanofiber membranes and test their ability for the treatment of wastewater containing Cibacron Brilliant Yellow 3G-P, a widely used reactive dye. The polyethylenimine/polyvinyl chloride membrane (PEI/PVCM) was characterized by FTIR, FE-SEM, TGA, tensile analysis, water contact angle measurement, and zeta-potential analysis. The FTIR analysis confirmed that the PEI has successfully crosslinked with PVC. The FE-SEM images showed that the nanofibers constituting PEI/PVCM are compact with an average fiber diameter of 181 nm. The TGA results showed that the membrane was able to remain stable in wastewater below 150 °C. The average stress and strain of the PEI/PVCM were 7.64 ± 0.32 MPa and 934.14 ± 48.12%, respectively. The water contact angle and zeta potential analysis showed that after the introduction of PEI, the membrane converted from hydrophobic to hydrophilic, and the pHpzc was increased from 3.1 to 1.08. The pure water flux of the membrane was measured at 0.1 MPa and the result was 3013 ± 60 L/m2‧h. The wastewater purification capability of PEI/PVCM was measured at an initial dye concentration of 10 ppm and pH 4-9 at 0.1 MPa. The reusability of PEI/PVCM was verified through three adsorption-desorption cycles. The results demonstrated that the PEI/PVCM is a reusable membrane for efficient purification of wastewater containing reactive dyes over a wide pH range (pH 4-8).


Assuntos
Nanofibras , Polietilenoimina , Adsorção , Ecossistema , Humanos , Nanofibras/química , Polietilenoimina/química , Cloreto de Polivinila , Águas Residuárias/química , Água
10.
Artigo em Inglês | MEDLINE | ID: mdl-35609354

RESUMO

In the study, purification of ovalbumin was performed by modifying polyamide hollow fiber membranes using immobilized metal affinity chromatography technique. For this purpose, firstly polyethyleneimine (PEI) solutions of different concentrations were attached to hollow fiber membranes. Then, Cu(II), Ni(II) and Zn(II) metal ions were chelated separately to polyethyleneimine attached hollow fiber membranes. Characterization studies of modified hollow fiber membranes were performed with scanning electron microscopy (SEM). Also, the surface area was measured with the Brunner Emmet Teller (BET) method and the porosity was measured with mercury porosimeter. pH, ionic strength, initial ovalbumin concentration, temperature and reusability parameters affecting adsorption capacity were investigated. The maximum ovalbumin adsorption capacities of hollow fiber membranes were found to be 317 mg/g for Cu(II), 169 mg/g for Ni(II) and 101 mg/g for Zn(II), respectively. Desorption ratio of metal ions were calculated as 91.6% for Cu(II), 92.9% for Ni(II) and 91.8% for Zn(II), which are quite high and suitable. When examined in terms of adsorption isotherm models, it was concluded that the Langmuir model is suitable. Purification of ovalbumin from egg white was carried out by fast performance liquid chromatography (FPLC), and the purity of ovalbumin was evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) method.


Assuntos
Clara de Ovo , Nylons , Adsorção , Concentração de Íons de Hidrogênio , Íons , Membranas Artificiais , Metais/química , Nylons/química , Ovalbumina , Polietilenoimina
11.
PLoS One ; 17(5): e0266181, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35507584

RESUMO

Lung cancer is known to be one of the fatal diseases in the world and is experiencing treatment difficulties. Many treatments have been discovered and implemented, but death rate of patients with lung cancer continues to remain high. Current treatments for cancer such as chemotherapy, immunotherapy, and radiotherapy have shown considerable results, yet they are accompanied by side effects. One effective method for reducing the cytotoxicity of these treatments is via the use of a nanoparticle-mediated siRNA delivery strategy with selective silencing effects and non-viral vectors. In this study, a folate (FA) moiety ligand-conjugated poly(sorbitol-co-PEI)-based gene transporter was designed by combining low-molecular weight polyethyleneimine (LMW PEI) and D-sorbitol with FA to form FPS. Since folate receptors are commonly overexpressed in various cancer cells, folate-conjugated nanoparticles may be more effectively delivered to selective cancer cells. Additionally, siOPA1 was used to induce apoptosis through mitochondrial fusion. The OPA1 protein stability level is important for maintaining normal mitochondrial cristae structure and function, conserving the inner membrane structure, and protecting cells from apoptosis. Consequently, when FPS/siOPA1 was used for lung cancer in-vitro and in-vivo, it improved cell viability and cellular uptake.


Assuntos
Neoplasias Pulmonares , Sorbitol , Linhagem Celular Tumoral , Ácido Fólico/metabolismo , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Polietilenoimina/química , RNA Interferente Pequeno/metabolismo , Transfecção
12.
J Control Release ; 347: 175-182, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35526613

RESUMO

In therapeutic cancer vaccines, vaccine antigens must be efficiently delivered to the antigen-presenting cells (dendritic cells and macrophages) located in the lymphoid organs (lymph nodes and spleen) at the appropriate time to induce a potent antitumor immune response. Nanoparticle-based delivery systems in cancer immunotherapy are of great interest in recent year. We have developed a novel cancer vaccine that can use self-assembled polysaccharide nanogel of cholesteryl group-modified pullulan (CHP) as an antigen delivery system for clinical cancer immunotherapy for the first time. Additionally, we recently proposed a novel technology that uses CHP nanogels to regulate the function of tumor-associated macrophages, leading to an improvement in the tumor microenvironment. When combined with other immunotherapies, macrophage function modulation using CHP nanogels demonstrated a potent inhibitory effect against cancers resistant to immune checkpoint inhibition therapies. In this review, we discuss the applications of our unique drug nanodelivery system for CHP nanogels.


Assuntos
Vacinas Anticâncer , Neoplasias , Antígenos , Humanos , Nanogéis , Neoplasias/tratamento farmacológico , Polietilenoglicóis , Polietilenoimina , Polissacarídeos , Microambiente Tumoral
13.
Chemosphere ; 303(Pt 1): 134925, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35561766

RESUMO

The manganese is successfully induced as a "bridge joint" to fabricate a new adsorbent (CNC-Mn-PEI) connecting cellulose nanocrystal (CNC) and polyethyleneimine (PEI) respectively. It was used to remove As (III) from waste water. It has been proved that the incompact CNC and PEI were successfully connected by Mn ions, which induced the formation of O-Mn-O bonds and the removal efficiency is maintained in the broad pH range of 4-8, even with the influence of NO3- and CO32-. The CNC-Mn-PEI was characterized by Brunauer-Emmett-Telley (BET) method and the results showed that the nanoparticle of the specific surface area was 106.5753 m2/g, it has a significant improvement, compared with CNC-Mn-DW (0.1918 m2/g). The isotherm and kinetic parameters of arsenic removal on CNC-Mn-PEI were well-fitted by the Langmuir and pseudo-second-order models. The maximum adsorption capacities toward As (III) was 78.02 mg/g. After seven regeneration cycles, the removal of As (III) by the adsorbent decreased from 80.78% to 68.2%. Additionally, the hypothetical adsorption mechanism of "bridge joint" effect was established by FTIR and XPS, which provided the three activated sites from CNC-Mn-PEI can improve the arsenic removal efficiency, and providing a new stratagem for the arsenic pollution treatment.


Assuntos
Arsênio , Arsenitos , Nanocompostos , Nanopartículas , Poluentes Químicos da Água , Adsorção , Arsênio/química , Arsenitos/química , Celulose/química , Concentração de Íons de Hidrogênio , Íons , Cinética , Manganês/química , Nanopartículas/química , Polietilenoimina/química , Poluentes Químicos da Água/análise
14.
J Vis Exp ; (183)2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35635449

RESUMO

microRNSa (miRNAs), small noncoding RNAs (21-25 bases) that are not translated into proteins, inhibit lots of target messenger RNAs (mRNAs) by destabilizing and inhibiting their translation in various kidney diseases. Therefore, alternation of miRNA expression by exogenous artificially synthesized miRNA mimics is a potentially useful treatment option for inhibiting the development of many kidney diseases. However, because serum RNAase immediately degrades systematically administered exogenous miRNA mimics in vivo, delivery of miRNA to the kidney remains a challenge. Therefore, vectors that can protect exogenous miRNA mimics from degradation by RNAase and significantly deliver them to the kidney are necessary. Many studies have used viral vectors to deliver exogenous miRNA mimics or inhibitors to the kidney. However, viral vectors may cause an interferon response and/or genetic instability. Therefore, the development of viral vectors is also a hurdle for the clinical use of exogenous miRNA mimics or inhibitors. To overcome these concerns regarding viral vectors, we developed a nonviral vector method to deliver miRNA mimics to the kidney using tail vein injection of polyethylenimine nanoparticles (PEI-NPs), which led to significant overexpression of target miRNAs in several mouse models of kidney disease.


Assuntos
Nefropatias , MicroRNAs , Nanopartículas , Animais , Rim/metabolismo , Nefropatias/genética , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Polietilenoimina , RNA Mensageiro
15.
J Hazard Mater ; 436: 129112, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35605498

RESUMO

Herein, we represent a novel ecofriendly bilayer-amine group incorporated microcrystalline cellulose (MCC)/chitosan (CS) hydrogel, fabricated via integrating polydopamine (PDA) and polyethyleneimine (PEI) for reliable and effective extraction of copper (Cu2+), zinc (Zn2+), and nickel (Ni2+) ions from effluents. Owing to abundant adsorptive sites, the MCC-PDA-PEI/CS-PDA-PEI hydrogel showed excellent Cu2+, Zn2+, and Ni2+ adsorbabilities of ~434.8, ~277.7, and ~261.8 mg/g, respectively, in a single-ion adsorption system with the adsorption kinetics and isotherm complied with pseudo-second-order and Langmuir models, respectively. In a multi-ion adsorption system, hydrogel removes mixed metal cations with slightly higher selectivity for Cu2+. In accordance with X-ray photoelectron and Fourier-transform-infrared spectrometric analyses, a plausible binding mechanism of metal cations on the as-prepared hydrogel was proposed by chelation between hydrogel functional groups and metal ions. In the repetitive adsorption/desorption experiments, the hydrogel retained >40% metal ion adsorption and desorption capacities after four cycles. Furthermore, the Cu2+-adsorbing hydrogel could serve as a support for the in situ development of Cu nanoparticles, which showed excellent catalytic performance as demonstrated by the transformation of 4-nitrophenol (4-NP) to 4-aminophenol. This work provides a novel ecofriendly, reusable, and highly-efficient adsorbent, as well as a biocatalyst for remediation of heavy metal cations and 4-NP polluted effluents.


Assuntos
Quitosana , Poluentes Químicos da Água , Purificação da Água , Adsorção , Aminas/química , Catálise , Cátions , Celulose , Quitosana/química , Hidrogéis , Concentração de Íons de Hidrogênio , Cinética , Polietilenoimina , Água/química , Poluentes Químicos da Água/química , Purificação da Água/métodos
16.
Mikrochim Acta ; 189(6): 217, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35538261

RESUMO

An ultrasensitive fluorescence assay strategy on the basis of carbon dots (CDs) and cDNA-modified gold nanoparticles (AuNP-cDNA) was developed for the determination of microRNA-21 (miRNA-21) via internal filtering effect (IFE). Positively charged CDs (PEI-CDs), the fluorophores in IFE, were synthesized via a hydrothermal method using polyethyleneimine (PEI) as surface ligand. The maximum emission wavelength is located at 500 nm under the excitation of 410 nm. AuNPs, the absorbers, were modified with single-stranded DNA (cDNA), which is completely complementary to miRNA-21. The fluorescence of PEI-CDs is quenched due to the assembly of PEI-CDs and AuNPs-cDNA. In the presence of miRNA-21, the hybridization between miRNA-21 and cDNA causes the release of PEI-CDs and the recovery of fluorescence intensity.The fluorescence recovery degree is linearly correlated with the logarithm of miRNA-21 concentration in the range of 1-1000 fM. This method can be applied to determine miRNA-21 in real serum samples, and the detection results are in well agreement with those of qRT-PCR. The determination of miRNA-21 spiked into diluted human serum samples displays satisfactory recovery within the range 88.44-112.7%, which confirmed the reliability for miRNAs detection in real samples.


Assuntos
Nanopartículas Metálicas , MicroRNAs , Pontos Quânticos , Carbono , DNA/análise , DNA/genética , DNA Complementar , Ouro , Humanos , Limite de Detecção , MicroRNAs/análise , Polietilenoimina , Reprodutibilidade dos Testes
17.
Carbohydr Polym ; 290: 119499, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35550777

RESUMO

As an important transcription factor, c-Jun could upregulate growth factors expression in Schwann cells (SCs). Arginine-Glycine-Aspartate (RGD)-functionalized chitosan-graft-polyethyleneimine (RCP) gene vectors were prepared through the maleic anhydride & the carbodiimide methods, and electrostatically bound with c-Jun plasmids (pJUN), finally loaded on poly-L-lactic acid/silk fibroin parallel fiber films to fabricate nerve scaffold (RCP/pJUN-PSPF@PGA), which could locally deliver c-Jun plasmids into SCs via the mediation of RGD peptides, and upregulate the expression of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) in SCs. After the scaffold was bridged in sciatic nerve defect, the delivery of c-Jun plasmids from RCP/pJUN-PSPF@PGA facilitated SCs to sustain the expressions of NGF, BDNF and vascular endothelial growth factor in the injury field, promoting myelination, axonal growth and microvascular generation and nerve regeneration, muscle reinnervation and functional recovery. These results suggested that RCP/pDNA-PSPF@PGA, as an effective gene delivery platform, could provide a local gene therapy to improve nerve regeneration.


Assuntos
Quitosana , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Quitosana/metabolismo , Terapia Genética , Fator de Crescimento Neural/genética , Fator de Crescimento Neural/metabolismo , Regeneração Nervosa , Oligopeptídeos , Polietilenoimina/metabolismo , Prostaglandinas A/metabolismo , Células de Schwann , Nervo Isquiático/lesões , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
18.
Chemosphere ; 302: 134910, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35551933

RESUMO

A Co2+ adsorbent was prepared using electrospun porous polyacrylonitrile (PAN) nanofibers, featuring easy recovery for reuse compared with a nanoparticle-based adsorbent. As an efficient ligand for Co2+, ethylenediaminetetraacetic acid (EDTA) was introduced on the surface of porous PAN nanofibers with the aid of a branched polyethyleneimine (PEI) linker to obtain an adsorbent with carboxylic acid groups. On the adsorbent surface, the carboxylic acid and amine groups from EDTA could adsorb Co2+ via ion exchange and chelation, and amine groups from PEI that remained after EDTA functionalization played a role in coordinating Co2+. The amine and carboxylic acid groups were simultaneously involved in the adsorption on the surface, making it possible to remove Co2+ over a wide pH range. An investigation of the adsorption isotherms and kinetics of the nanofibrous adsorbent indicated that monolayer chemisorption was achieved with a maximum Co2+ adsorption capacity of 8.32 mg/g. In addition, radioactive 60Co was efficiently removed by the adsorbent with a removal extent of more than 98%. Considering the easy separation from Co2+ solution and regeneration of the nanofibrous adsorbent and its availability in a wide pH range, the adsorbent has great advantages in practical applications.


Assuntos
Nanofibras , Purificação da Água , Resinas Acrílicas , Adsorção , Ácido Edético , Polietilenoimina , Porosidade
19.
Int J Mol Sci ; 23(9)2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35563121

RESUMO

In case of an incident in the nuclear industry or an act of war or terrorism, the dissemination of plutonium could contaminate the environment and, hence, humans. Human contamination mainly occurs via inhalation and/or wounding (and, less likely, ingestion). In such cases, plutonium, if soluble, reaches circulation, whereas the poorly soluble fraction (such as small colloids) is trapped in alveolar macrophages or remains at the site of wounding. Once in the blood, the plutonium is delivered to the liver and/or to the bone, particularly into its mineral part, mostly composed of hydroxyapatite. Countermeasures against plutonium exist and consist of intravenous injections or inhalation of diethylenetetraminepentaacetate salts. Their effectiveness is, however, mainly confined to the circulating soluble forms of plutonium. Furthermore, the short bioavailability of diethylenetetraminepentaacetate results in its rapid elimination. To overcome these limitations and to provide a complementary approach to this common therapy, we developed polymeric analogs to indirectly target the problematic retention sites. We present herein a first study regarding the decontamination abilities of polyethyleneimine methylcarboxylate (structural diethylenetetraminepentaacetate polymer analog) and polyethyleneimine methylphosphonate (phosphonate polymeric analog) directed against Th(IV), used here as a Pu(IV) surrogate, which was incorporated into hydroxyapatite used as a bone model. Our results suggest that polyethylenimine methylphosphonate could be a good candidate for powerful bone decontamination action.


Assuntos
Elementos da Série Actinoide , Plutônio , Quelantes/química , Descontaminação/métodos , Durapatita , Humanos , Plutônio/química , Polietilenoimina , Polímeros
20.
Int J Mol Sci ; 23(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35563405

RESUMO

Polyethylenimine (PEI) has been widely used in gene delivery. However, its high cytotoxicity and undesired non-specific protein adsorption hinder the overall delivery efficacy and the practical applications of PEI-based gene delivery systems. In this study, we prepared hydrophobically modified PEIs (H-PEIs) via the reaction of octanal with 40% of primary amines in PEI25k and PEI10k, respectively. Two common zwitterionic molecules, 1,3-propanesultone and ß-propiolactone, were then used for the modification of the resulting H-PEIs to construct polycationic gene carriers with zwitterionic properties (H-zPEIs). The siRNA delivery efficiency and cytotoxicity of these materials were evaluated in Hela-Luc and A549-Luc cell lines. Compared with their respective parental H-PEIs, different degrees of zwitterionic modification showed different effects in reducing cytotoxicity and delivery efficiency. All zwitterion-modified PEIs showed excellent siRNA binding capacity, reduced nonspecific protein adsorption, and enhanced stability upon nuclease degradation. It is concluded that zwitterionic molecular modification is an effective method to construct efficient vectors by preventing undesired interactions between polycationic carriers and biomacromolecules. It may offer insights into the modification of other cationic carriers of nucleic acid drugs.


Assuntos
Técnicas de Transferência de Genes , Polietilenoimina , Terapia Genética , Células HeLa , Humanos , Polietilenoimina/química , RNA Interferente Pequeno/metabolismo , Transfecção
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