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1.
AAPS PharmSciTech ; 25(5): 103, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714634

RESUMO

Crystallization of amorphous pharmaceutical solids are widely reported to be affected by the addition of polymer, while the underlying mechanism require deep study. Herein, crystal growth behaviors of glassy griseofulvin (GSF) doped with various 1% w/w polymer were systematically studied. From the molecular structure, GSF cannot form the hydrogen bonding interactions with the selected polymer poly(vinyl acetate), polyvinyl pyrrolidone (PVP), 60:40 vinyl pyrrolidone-vinyl acetate copolymer (PVP/VA 64), and poly(ethylene oxide) (PEO). 1% w/w polymer exhibited weak or no detectable effects on the glass transition temperature (Tg) of GSF. However, crystal growth rates of GSF was altered from 4.27-fold increase to 2.57-fold decrease at 8 ℃ below Tg of GSF. Interestingly, the ability to accelerate and inhibit the growth rates of GSF crystals correlated well with Tg of polymer, indicating the controlling role of segmental mobility of polymer. Moreover, ring-banded growth of GSF was observed in the polymer-doped systems. Normal compact bulk and ring-banded crystals of GSF were both characterized as the thermodynamically stable form I. More importantly, formation of ring-banded crystals of GSF can significantly weaken the inhibitory effects of polymer on the crystallization of glassy GSF.


Assuntos
Cristalização , Griseofulvina , Polímeros , Temperatura de Transição , Griseofulvina/química , Cristalização/métodos , Polímeros/química , Estabilidade de Medicamentos , Ligação de Hidrogênio , Polivinil/química , Polietilenoglicóis/química , Povidona/química , Vidro/química
2.
Food Res Int ; 186: 114340, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729695

RESUMO

Fruits are essential sources of nutrients in our daily diet; however, their spoilage is often intensified by mechanical damage and the ethylene phytohormone, resulting in significant economic losses and exacerbating hunger issues. To address these challenges, this study presented a straightforward in situ synthesis protocol for producing Z/SOPPU foam, a 3D porous-structured fruit packaging. This innovative packaging material offered advanced ethylene-adsorbing and cushioning capabilities achieved through stirring, heating, and standing treatments. The results demonstrated that the Z/SOPPU foam, with its porous structure, served as an excellent packaging material for fruits, maintaining the intact appearance of tomatoes even after being thrown 72 times from a height of 1.5 m. Additionally, it exhibited desirable hydrophobicity (contact angle of 114.31 ± 0.82°), degradability (2.73 ± 0.88 % per 4 weeks), and efficient ethylene adsorption (adsorption rate of 13.2 ± 1.7 mg/m3/h). These remarkable characteristics could be attributed to the unique 3D micron-porous configuration, consisting of soybean oil polyol polyurethane foam for mechanical strain cushioning and zein for enhanced ethylene adsorption efficiency. Overall, this research offers an effective and original approach to the rational design and fabrication of advanced bio-based fruit packaging.


Assuntos
Etilenos , Embalagem de Alimentos , Frutas , Poliuretanos , Óleo de Soja , Zeína , Etilenos/química , Poliuretanos/química , Embalagem de Alimentos/métodos , Porosidade , Frutas/química , Óleo de Soja/química , Zeína/química , Adsorção , Polímeros/química , Solanum lycopersicum/química , Interações Hidrofóbicas e Hidrofílicas
3.
Biomed Mater ; 19(4)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38697132

RESUMO

During the process of malignant tumor treatment, photodynamic therapy (PDT) exerts poor efficacy due to the hypoxic environment of the tumor cells, and long-time chemotherapy reduces the sensitivity of tumor cells to chemotherapy drugs due to the presence of drug-resistant proteins on the cell membranes for drug outward transportation. Therefore, we reported a nano platform based on mesoporous silica coated with polydopamine (MSN@PDA) loading PDT enhancer MnO2, photosensitizer indocyanine green (ICG) and chemotherapeutic drug doxorubicin (DOX) (designated as DMPIM) to achieve a sequential release of different drugs to enhance treatment of malignant tumors. MSN was first synthesized by a template method, then DOX was loaded into the mesoporous channels of MSN, and locked by the PDA coating. Next, ICG was modified by π-π stacking on PDA, and finally, MnO2layer was accumulated on the surface of DOX@MSN@PDA- ICG@MnO2, achieving orthogonal loading and sequential release of different drugs. DMPIM first generated oxygen (O2) through the reaction between MnO2and H2O2after entering tumor cells, alleviating the hypoxic environment of tumors and enhancing the PDT effect of sequentially released ICG. Afterwards, ICG reacted with O2in tumor tissue to produce reactive oxygen species, promoting lysosomal escape of drugs and inactivation of p-glycoprotein (p-gp) on tumor cell membranes. DOX loaded in the MSN channels exhibited a delay of approximately 8 h after ICG release to exert the enhanced chemotherapy effect. The drug delivery system achieved effective sequential release and multimodal combination therapy, which achieved ideal therapeutic effects on malignant tumors. This work offers a route to a sequential drug release for advancing the treatment of malignant tumors.


Assuntos
Doxorrubicina , Liberação Controlada de Fármacos , Verde de Indocianina , Indóis , Compostos de Manganês , Óxidos , Fotoquimioterapia , Fármacos Fotossensibilizantes , Polímeros , Fotoquimioterapia/métodos , Doxorrubicina/química , Doxorrubicina/farmacologia , Doxorrubicina/administração & dosagem , Verde de Indocianina/química , Indóis/química , Animais , Compostos de Manganês/química , Humanos , Polímeros/química , Linhagem Celular Tumoral , Óxidos/química , Fármacos Fotossensibilizantes/química , Dióxido de Silício/química , Camundongos , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/administração & dosagem , Neoplasias/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Portadores de Fármacos/química , Porosidade
4.
J Nanobiotechnology ; 22(1): 264, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760771

RESUMO

Glioblastoma (GBM) is the most aggressive primary brain tumor with low survival rate. Currently, temozolomide (TMZ) is the first-line drug for GBM treatment of which efficacy is unfortunately hindered by short circulation time and drug resistance associated to hypoxia and redox tumor microenvironment. Herein, a dual-targeted and multi-responsive nanoplatform is developed by loading TMZ in hollow manganese dioxide nanoparticles functionalized by polydopamine and targeting ligands RAP12 for photothermal and receptor-mediated dual-targeted delivery, respectively. After accumulated in GBM tumor site, the nanoplatform could respond to tumor microenvironment and simultaneously release manganese ion (Mn2+), oxygen (O2) and TMZ. The hypoxia alleviation via O2 production, the redox balance disruption via glutathione consumption and the reactive oxygen species generation, together would down-regulate the expression of O6-methylguanine-DNA methyltransferase under TMZ medication, which is considered as the key to drug resistance. These strategies could synergistically alleviate hypoxia microenvironment and overcome TMZ resistance, further enhancing the anti-tumor effect of chemotherapy/chemodynamic therapy against GBM. Additionally, the released Mn2+ could also be utilized as a magnetic resonance imaging contrast agent for monitoring treatment efficiency. Our study demonstrated that this nanoplatform provides an alternative approach to the challenges including low delivery efficiency and drug resistance of chemotherapeutics, which eventually appears to be a potential avenue in GBM treatment.


Assuntos
Neoplasias Encefálicas , Resistencia a Medicamentos Antineoplásicos , Glioblastoma , Compostos de Manganês , Nanopartículas , Óxidos , Temozolomida , Microambiente Tumoral , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Microambiente Tumoral/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Linhagem Celular Tumoral , Animais , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Nanopartículas/química , Neoplasias Encefálicas/tratamento farmacológico , Óxidos/química , Óxidos/farmacologia , Camundongos , Sistemas de Liberação de Medicamentos/métodos , Indóis/química , Indóis/farmacologia , Polímeros/química , Camundongos Nus , Camundongos Endogâmicos BALB C , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo
5.
Arch Microbiol ; 206(6): 275, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38775940

RESUMO

In many European regions, both local metallic and non-metallic raw materials are poorly exploited due to their low quality and the lack of technologies to increase their economic value. In this context, the development of low cost and eco-friendly approaches, such as bioleaching of metal impurities, is crucial. The acidophilic strain Acidiphilium sp. SJH reduces Fe(III) to Fe(II) by coupling the oxidation of an organic substrate to the reduction of Fe(III) and can therefore be applied in the bioleaching of iron impurities from non-metallic raw materials. In this work, the physiology of Acidiphilium sp. SJH and the reduction of iron impurities from quartz sand and its derivatives have been studied during growth on media supplemented with various carbon sources and under different oxygenation conditions, highlighting that cell physiology and iron reduction are tightly coupled. Although the organism is known to be aerobic, maximum bioleaching performance was obtained by cultures cultivated until the exponential phase of growth under oxygen limitation. Among carbon sources, glucose has been shown to support faster biomass growth, while galactose allowed highest bioleaching. Moreover, Acidiphilium sp. SJH cells can synthesise and accumulate Poly-ß-hydroxybutyrate (PHB) during the process, a polymer with relevant application in biotechnology. In summary, this work gives an insight into the physiology of Acidiphilium sp. SJH, able to use different carbon sources and to synthesise a technologically relevant polymer (PHB), while removing metals from sand without the need to introduce modifications in the process set up.


Assuntos
Acidiphilium , Ferro , Oxirredução , Ferro/metabolismo , Acidiphilium/metabolismo , Acidiphilium/crescimento & desenvolvimento , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo , Polímeros/metabolismo , Meios de Cultura/química , Biomassa , Poli-Hidroxibutiratos
6.
Int J Nanomedicine ; 19: 4163-4180, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38751660

RESUMO

Purpose: The study aimed to address the non-specific toxicity of cytotoxins (CTX) in liver cancer treatment and explore their combined application with the photosensitizer Ce6, co-loaded into carbonized Zn/Co bimetallic organic frameworks. The goal was to achieve controlled CTX release and synergistic photodynamic therapy, with a focus on evaluating anti-tumor activity against human liver cancer cell lines (Hep G2). Methods: Purified cobra cytotoxin (CTX) and photosensitizer Ce6 were co-loaded into carbonized Zn/Co bimetallic organic frameworks, resulting in RGD-PDA@C-ZIF@(CTX+Ce6). The formulation was designed with surface-functionalization using polydopamine and tumor-penetrating peptide RGD. This approach aimed to facilitate controlled CTX release and enhance the synergistic effect of photodynamic therapy. The accumulation of RGD-PDA@C-ZIF@(CTX+Ce6) at tumor sites was achieved through RGD's active targeting and the enhanced permeability and retention (EPR) effect. In the acidic tumor microenvironment, the porous structure of the metal-organic framework disintegrated, releasing CTX and Ce6 into tumor cells. Results: Experiments demonstrated that RGD-PDA@C-ZIF@(CTX+Ce6) nanoparticles, combined with near-infrared laser irradiation, exhibited optimal anti-tumor effects against human liver cancer cells. The formulation showcased heightened anti-tumor activity without discernible systemic toxicity. Conclusion: The study underscores the potential of utilizing metal-organic frameworks as an efficient nanoplatform for co-loading cytotoxins and photodynamic therapy in liver cancer treatment. The developed formulation, RGD-PDA@C-ZIF@(CTX+Ce6), offers a promising avenue for advancing the clinical application of cytotoxins in oncology, providing a solid theoretical foundation for future research and development.


Assuntos
Indóis , Neoplasias Hepáticas , Estruturas Metalorgânicas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Zinco , Humanos , Fotoquimioterapia/métodos , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Zinco/química , Zinco/farmacologia , Indóis/química , Indóis/farmacologia , Indóis/administração & dosagem , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/administração & dosagem , Animais , Células Hep G2 , Cobalto/química , Cobalto/farmacologia , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Oligopeptídeos/farmacocinética , Polímeros/química , Camundongos , Citotoxinas/química , Citotoxinas/farmacologia , Citotoxinas/farmacocinética , Camundongos Nus , Camundongos Endogâmicos BALB C , Sobrevivência Celular/efeitos dos fármacos
7.
Anal Chem ; 96(19): 7697-7705, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38697043

RESUMO

Dual/multimodal imaging strategies are increasingly recognized for their potential to provide comprehensive diagnostic insights in cancer imaging by harnessing complementary data. This study presents an innovative probe that capitalizes on the synergistic benefits of afterglow luminescence and magnetic resonance imaging (MRI), effectively eliminating autofluorescence interference and delivering a superior signal-to-noise ratio. Additionally, it facilitates deep tissue penetration and enables noninvasive imaging. Despite the advantages, only a limited number of probes have demonstrated the capability to simultaneously enhance afterglow luminescence and achieve high-resolution MRI and afterglow imaging. Herein, we introduce a cutting-edge imaging platform based on semiconducting polymer nanoparticles (PFODBT) integrated with NaYF4@NaGdF4 (Y@Gd@PFO-SPNs), which can directly amplify afterglow luminescence and generate MRI and afterglow signals in tumor tissues. The proposed mechanism involves lanthanide nanoparticles producing singlet oxygen (1O2) upon white light irradiation, which subsequently oxidizes PFODBT, thereby intensifying afterglow luminescence. This innovative platform paves the way for the development of high signal-to-background ratio imaging modalities, promising noninvasive diagnostics for cancer.


Assuntos
Elementos da Série dos Lantanídeos , Imageamento por Ressonância Magnética , Nanopartículas , Polímeros , Semicondutores , Imageamento por Ressonância Magnética/métodos , Animais , Elementos da Série dos Lantanídeos/química , Polímeros/química , Nanopartículas/química , Camundongos , Humanos , Gadolínio/química , Luminescência , Oxigênio Singlete/química , Ítrio/química , Fluoretos/química , Camundongos Nus
8.
Front Immunol ; 15: 1396486, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38694497

RESUMO

Bone marrow failure (BMF) has become one of the most studied autoimmune disorders, particularly due to its prevalence both as an inherited disease, but also as a result of chemotherapies. BMF is associated with severe symptoms such as bleeding episodes and susceptibility to infections, and often has underlying characteristics, such as anemia, thrombocytopenia, and neutropenia. The current treatment landscape for BMF requires stem cell transplantation or chemotherapies to induce immune suppression. However, there is limited donor cell availability or dose related toxicity associated with these treatments. Optimizing these treatments has become a necessity. Polymer-based materials have become increasingly popular, as current research efforts are focused on synthesizing novel cell matrices for stem cell expansion to solve limited donor cell availability, as well as applying polymer delivery vehicles to intracellularly deliver cargo that can aid in immunosuppression. Here, we discuss the importance and impact of polymer materials to enhance therapeutics in the context of BMF.


Assuntos
Polímeros , Humanos , Polímeros/química , Animais , Doenças da Medula Óssea/induzido quimicamente , Doenças da Medula Óssea/terapia , Transtornos da Insuficiência da Medula Óssea/terapia , Materiais Biocompatíveis
9.
Biomacromolecules ; 25(5): 3153-3162, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38693895

RESUMO

A photoacoustic (PA) imaging technique using the second near-infrared (NIR-II) window has attracted more and more attention because of its merits of deeper penetration depth and higher signal-to-noise (S/N) ratio than that using the first near-infrared (NIR-I) one. However, the design and development of high-performance PA imaging contrast agents in the NIR-II window is still a challenge. A semiconducting polymer, constructed by asymmetric units, exhibits regiorandom characteristics that effectively increase the distortion of the backbone. This increase in the degree of twist can regulate the twisted intramolecular charge transfer (TICT) effect, resulting in an enhancement of the PA signal. In this paper, an asymmetric structural acceptor strategy is developed to improve the PA signals of the resulting semiconducting polymer (PATQ-MP) in the NIR-II window with improved brightness, higher S/N ratio, and better photothermal conversion efficiency compared to polymers with the same main-chain structure containing a symmetric acceptor. DFT analysis showed that PATQ-MP containing an asymmetric acceptor monomer had a larger dihedral angle, which effectively improved the PA signal intensity by enhancing the TICT effect. The PEG-encapsulated PATQ-MP nanoparticles exhibit promising performance in the PA imaging of mouse tumors in vivo, demonstrating the clear identification of microvessels as small as 100 µm along with rapid metabolism within a span of 5 h. Therefore, this work provides a unique molecular design strategy for improving the signal intensity of PA imaging in the NIR-II window.


Assuntos
Técnicas Fotoacústicas , Polímeros , Semicondutores , Técnicas Fotoacústicas/métodos , Animais , Camundongos , Polímeros/química , Quinoxalinas/química , Feminino , Humanos , Tiadiazóis/química , Raios Infravermelhos , Camundongos Nus , Camundongos Endogâmicos BALB C , Meios de Contraste/química
10.
Biomacromolecules ; 25(5): 3122-3130, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38696355

RESUMO

Synthesis of polysaccharide-b-polypeptide block copolymers represents an attractive goal because of their promising potential in delivery applications. Inspired by recent breakthroughs in N-carboxyanhydride (NCA) ring-opening polymerization (ROP), we present an efficient approach for preparation of a dextran-based macroinitiator and the subsequent synthesis of dextran-b-polypeptides via NCA ROP. This is an original approach to creating and employing a native polysaccharide macroinitiator for block copolymer synthesis. In this strategy, regioselective (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) oxidation of the sole primary alcohol located at the C-6 position of the monosaccharide at the nonreducing end of linear dextran results in a carboxylic acid. This motif is then transformed into a tetraalkylammonium carboxylate, thereby generating the dextran macroinitiator. This macroinitiator initiates a wide range of NCA monomers and produces dextran-b-polypeptides with a degree of polymerization (DP) of the polypeptide up to 70 in a controlled manner (D < 1.3). This strategy offers several distinct advantages, including preservation of the original dextran backbone structure, relatively rapid polymerization, and moisture tolerance. The dextran-b-polypeptides exhibit interesting self-assembly behavior. Their nanostructures have been investigated by dynamic light scattering (DLS) and transmission electron microscopy (TEM), and adjustment of the structure of block copolymers allows self-assembly of spherical micelles and worm-like micelles with varied diameters and aspect ratios, revealing a range of diameters from 60 to 160 nm. Moreover, these nanostructures exhibit diverse morphologies, including spherical micelles and worm-like micelles, enabling delivery applications.


Assuntos
Dextranos , Peptídeos , Polimerização , Dextranos/química , Peptídeos/química , Peptídeos/síntese química , Polímeros/química , Polímeros/síntese química , Óxidos N-Cíclicos/química , Anidridos/química , Polissacarídeos/química , Micelas
11.
Nat Commun ; 15(1): 3902, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724527

RESUMO

Radiation-induced in situ tumor vaccination alone is very weak and insufficient to elicit robust antitumor immune responses. In this work, we address this issue by developing chiral vidarabine monophosphate-gadolinium nanowires (aAGd-NWs) through coordination-driven self-assembly. We elucidate the mechanism of aAGd-NW assembly and characterize their distinct features, which include a negative surface charge, ultrafine topography, and right-handed chirality. Additionally, aAGd-NWs not only enhance X-ray deposition but also inhibit DNA repair, thereby enhancing radiation-induced in situ vaccination. Consequently, the in situ vaccination induced by aAGd-NWs sensitizes radiation enhances CD8+ T-cell-dependent antitumor immunity and synergistically potentiates the efficacy immune checkpoint blockade therapies against both primary and metastatic tumors. The well-established aAGd-NWs exhibit exceptional therapeutic capacity and biocompatibility, offering a promising avenue for the development of radioimmunotherapy approaches.


Assuntos
Nanofios , Polímeros , Nanofios/química , Animais , Camundongos , Polímeros/química , Linhagem Celular Tumoral , Gadolínio/química , Gadolínio/farmacologia , Camundongos Endogâmicos C57BL , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Vacinas Anticâncer/imunologia , Feminino , Humanos , Vacinação/métodos , Neoplasias/imunologia
12.
Int J Mol Sci ; 25(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38731902

RESUMO

Investigation of chiroptical polymers in the solution phase is paramount for designing supramolecular architectures for photonic or biomedical devices. This work is devoted to the case study of poly(propylene oxide) (PPO) optical activity in several solvents: benzonitrile, carbon disulfide, chloroform, ethyl acetate, and p-dioxane. To attain information on the interactions in these systems, rheological testing was undertaken, showing distinct variations of the rheological parameters as a function of the solvent type. These aspects are also reflected in the refractive index dispersive behavior, from which linear and non-linear optical properties are extracted. To determine the circular birefringence and specific rotation of the PPO solutions, the alternative method of the channeled spectra was employed. The spectral data were correlated with the molecular modeling of the PPO structural unit in the selected solvents. Density functional theory (DFT) computational data indicated that the torsional potential energy-related to the O1-C2-C3-O4 dihedral angle from the polymer repeating unit-was hindered in solvation environments characterized by high polarity and the ability to interact via hydrogen bonding. This was in agreement with the optical characterization of the samples, which indicated a lower circular birefringence and specific rotation for the solutions of PPO in ethyl acetate and p-dioxane. Also, the shape of optical rotatory dispersion curves was slightly modified for PPO in these solvents compared with the other ones.


Assuntos
Solventes , Solventes/química , Propilenoglicóis/química , Polipropilenos/química , Polímeros/química , Modelos Moleculares , Rotação , Ligação de Hidrogênio , Reologia
13.
Int J Mol Sci ; 25(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731949

RESUMO

To enrich the properties of polylactic acid (PLA)-based composite films and improve the base degradability, in this study, a certain amount of poly(propylene carbonate) (PPC) was added to PLA-based composite films, and PLA/PPC-based composite films were prepared by melt blending and hot-press molding. The effects of the introduction of PPC on the composite films were analyzed through in-depth studies on mechanical properties, water vapor and oxygen transmission rates, thermal analysis, compost degradability, and bacterial inhibition properties of the composite films. When the introduction ratio coefficient of PPC was 30%, the tensile strength of the composite film increased by 19.68%, the water vapor transmission coefficient decreased by 14.43%, and the oxygen transmission coefficient decreased by 18.31% compared to that of the composite film without PPC, the cold crystallization temperature of the composite film increased gradually from 96.9 °C to 104.8 °C, and PPC improved the crystallization ability of composite film. The degradation rate of the composite film with PPC increased significantly compared to the previous one, and the degradation rate increased with the increase in the PPC content. The degradation rate was 49.85% and 46.22% faster on average than that of the composite film without PPC when the degradation was carried out over 40 and 80 days; the composite film had certain inhibition, and the maximum diameter of the inhibition circle was 2.42 cm. This study provides a strategy for the development of PLA-based biodegradable laminates, which can promote the application of PLA-based laminates in food packaging.


Assuntos
Poliésteres , Propano/análogos & derivados , Resistência à Tração , Poliésteres/química , Polipropilenos/química , Embalagem de Alimentos/métodos , Vapor , Polímeros/química , Antibacterianos/química , Antibacterianos/farmacologia , Temperatura
14.
Int J Mol Sci ; 25(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38732121

RESUMO

Today a lot of attention is paid to the formation of thermosensitive systems for biomedical and industrial applications. The development of new methods for synthesis of such systems is a dynamically developing direction in chemistry and materials science. In this regard, this paper presents results of the studies of a new synthesized supramolecular polymer system based on polyethylene glycol and tetrafluoroethylene telomers. The films formed from the polymer substance have the property of switching wettability depending on temperature after heating activation. It has been established that the wettability changes at 60 °C. The contact angle of activated hydrophobic polymer film reaches 143°. Additionally, the system exhibits its properties regardless of the pH of the environment. Based on data obtained by the methods of infrared and x-ray photoelectron spectroscopy, differential thermal analysis and thermal analysis in conjunction with wettability and morphology, a model of the behavior of molecules in a polymer system was built that ensures switching of the hydrophilic/hydrophobic surface state. The resulting polymer system, as well as films based on it, can be used in targeted drug delivery, implantation surgery, as sensors, etc.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Polietilenoglicóis , Molhabilidade , Polietilenoglicóis/química , Polímeros/química , Temperatura , Espectroscopia Fotoeletrônica
15.
Int J Mol Sci ; 25(9)2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38732235

RESUMO

The formulation of novel delivery protocols for the targeted delivery of genes into hepatocytes by receptor mediation is important for the treatment of liver-specific disorders, including cancer. Non-viral delivery methods have been extensively studied for gene therapy. Gold nanoparticles (AuNPs) have gained attention in nanomedicine due to their biocompatibility. In this study, AuNPs were synthesized and coated with polymers: chitosan (CS), and polyethylene glycol (PEG). The targeting moiety, lactobionic acid (LA), was added for hepatocyte-specific delivery. Physicochemical characterization revealed that all nano-formulations were spherical and monodispersed, with hydrodynamic sizes between 70 and 250 nm. Nanocomplexes with pCMV-Luc DNA (pDNA) confirmed that the NPs could bind, compact, and protect the pDNA from nuclease degradation. Cytotoxicity studies revealed that the AuNPs were well tolerated (cell viabilities > 70%) in human hepatocellular carcinoma (HepG2), embryonic kidney (HEK293), and colorectal adenocarcinoma (Caco-2) cells, with enhanced transgene activity in all cells. The inclusion of LA in the NP formulation was notable in the HepG2 cells, which overexpress the asialoglycoprotein receptor on their cell surface. A five-fold increase in luciferase gene expression was evident for the LA-targeted AuNPs compared to the non-targeted AuNPs. These AuNPs have shown potential as safe and suitable targeted delivery vehicles for liver-directed gene therapy.


Assuntos
Quitosana , Técnicas de Transferência de Genes , Ouro , Neoplasias Hepáticas , Nanopartículas Metálicas , Humanos , Ouro/química , Nanopartículas Metálicas/química , Células Hep G2 , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/genética , Quitosana/química , Células HEK293 , Receptor de Asialoglicoproteína/metabolismo , Receptor de Asialoglicoproteína/genética , Células CACO-2 , Luciferases/genética , Luciferases/metabolismo , Polietilenoglicóis/química , Plasmídeos/genética , Dissacarídeos/química , Terapia Genética/métodos , Polímeros/química , Sobrevivência Celular/efeitos dos fármacos
16.
Int J Mol Sci ; 25(9)2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38732246

RESUMO

Nanoparticles (NPs) have shown significant potential for pulmonary administration of therapeutics for the treatment of chronic lung diseases in a localized and sustained manner. Nebulization is a suitable method of NP delivery, particularly in patients whose ability to breathe is impaired due to lung diseases. However, there are limited studies evaluating the physicochemical properties of NPs after they are passed through a nebulizer. High shear stress generated during nebulization could potentially affect the surface properties of NPs, resulting in the loss of encapsulated drugs and alteration in the release kinetics. Herein, we thoroughly examined the physicochemical properties as well as the therapeutic effectiveness of Infasurf lung surfactant (IFS)-coated PLGA NPs previously developed by us after passing through a commercial Aeroneb® vibrating-mesh nebulizer. Nebulization did not alter the size, surface charge, IFS coating and bi-phasic release pattern exhibited by the NPs. However, there was a temporary reduction in the initial release of encapsulated therapeutics in the nebulized compared to non-nebulized NPs. This underscores the importance of evaluating the drug release kinetics of NPs using the inhalation method of choice to ensure suitability for the intended medical application. The cellular uptake studies demonstrated that both nebulized and non-nebulized NPs were less readily taken up by alveolar macrophages compared to lung cancer cells, confirming the IFS coating retention. Overall, nebulization did not significantly compromise the physicochemical properties as well as therapeutic efficacy of the prepared nanotherapeutics.


Assuntos
Nanopartículas , Nebulizadores e Vaporizadores , Nanopartículas/química , Humanos , Administração por Inalação , Sistemas de Liberação de Medicamentos/métodos , Lipídeos/química , Liberação Controlada de Fármacos , Pulmão/metabolismo , Polímeros/química , Surfactantes Pulmonares/química , Portadores de Fármacos/química , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/efeitos dos fármacos , Tamanho da Partícula , Células A549 , Animais , Propriedades de Superfície
17.
J Am Chem Soc ; 146(20): 13836-13845, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38717976

RESUMO

Hydrogels hold significant promise as drug delivery systems due to their distinct advantage of sustained localized drug release. However, the challenge of regulating the initial burst release while achieving precise control over degradation and drug-release kinetics persists. Herein, we present an ABA-type triblock copolymer-based hydrogel system with precisely programmable degradation and release kinetics. The resulting hydrogels were designed with a hydrophilic poly(ethylene oxide) midblock and a hydrophobic end-block composed of polyethers with varying ratios of ethoxyethyl glycidyl ether and tetrahydropyranyl glycidyl ether acetal pendant possessing different hydrolysis kinetics. This unique side-chain strategy enabled us to achieve a broad spectrum of precise degradation and drug-release profiles under mildly acidic conditions while maintaining the cross-linking density and viscoelastic modulus, which is unlike the conventional polyester-based backbone degradation system. Furthermore, programmable degradation of the hydrogels and release of active therapeutic agent paclitaxel loaded therein are demonstrated in an in vivo mouse model by suppressing tumor recurrence following surgical resection. Tuning of the fraction of two acetal pendants in the end-block provided delicate tailoring of hydrogel degradation and the drug release capability to achieve the desired therapeutic efficacy. This study not only affords a facile means to design hydrogels with precisely programmable degradation and release profiles but also highlights the critical importance of aligning the drug release profile with the target disease.


Assuntos
Liberação Controlada de Fármacos , Hidrogéis , Hidrogéis/química , Hidrogéis/síntese química , Animais , Camundongos , Acetais/química , Paclitaxel/química , Paclitaxel/farmacocinética , Éteres/química , Polietilenoglicóis/química , Polímeros/química , Polímeros/síntese química , Portadores de Fármacos/química
18.
Biomed Mater ; 19(4)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38729192

RESUMO

In this study, we coated electrospun polycaprolactone (PCL) fibers with polydopamine (PDA) to modify their hydrophobicity and fabricated a matrix for culturing mesenchymal stem cells (MSCs). Additionally, we incorporated Arg-Gly-Asp (RGD) peptides into PDA to enhance MSCs culture performance on PCL fibers. PDA and RGD were successfully coated in one step by immersing the electrospun fibers in a coating solution, without requiring an additional surface activation process. The characteristics of functionalized PCL fibers were analyzed by scanning electron microscopy with energy-dispersive x-ray analysis, Fourier transform infrared spectroscopy, water contact angle measurement, and fluorescence measurements using a carboxylic-modified fluorescent microsphere. MSCs cultured on the modified PCL fibers demonstrated enhanced cell adhesion, proliferation, and osteogenic- and chondrogenic differentiation. This study provides insight into potential applications for scaffold fabrication in MSCs-based tissue engineering, wound dressing, implantation, and a deeper understanding of MSCs behaviorin vitro.


Assuntos
Adesão Celular , Diferenciação Celular , Proliferação de Células , Indóis , Células-Tronco Mesenquimais , Osteogênese , Poliésteres , Polímeros , Engenharia Tecidual , Alicerces Teciduais , Células-Tronco Mesenquimais/citologia , Humanos , Polímeros/química , Indóis/química , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Poliésteres/química , Osteogênese/efeitos dos fármacos , Células Cultivadas , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Condrogênese/efeitos dos fármacos , Técnicas de Cultura de Células , Interações Hidrofóbicas e Hidrofílicas
19.
J Chromatogr A ; 1726: 464965, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38733925

RESUMO

Aristolochic acids (AAs) naturally occurring in the herbal genus Aristolochia are associated with a high risk of kidney failure, multiple tumors and cancers. However, approaches with high selectivity and rapidity for measuring AAs in biological samples are still inadequate. Inspired by the mechanism of AAs-induced nephrotoxicity, we designed a hybrid magnetic polymer-porous agarose (denoted as MNs@SiO2M@DNV-A), mimicking the effect of basic and aromatic residues of organic anion transporter 1 (OAT1) for efficient enriching aristolochic acid I (AA I) and aristolochic acid II (AA II) in the plasma. The monomers of vinylbenzyl trimethylammonium chloride (VBTAC), N-vinyl-2-pyrrolidinone (NVP) and divinylbenzene (DVB) were employed to construct the polymer layer, which provided a selective adsorption for AAs by multiple interactions. The porous agarose shell contributed to remove interfering proteins in the plasma samples. A magnetic solid-phase extraction (MSPE) based on the proposed composite enhanced the selectivity toward AA I and AA II in the plasma samples. In combination of HPLC analysis, the proposed method was proved to be applicable to fast and specific quantification of AAs in blood samples, which was characterized by a good linearity, high sensitivity, acceptable recovery, excellent repeatability and satisfactory reusability.


Assuntos
Ácidos Aristolóquicos , Compostos de Amônio Quaternário , Sefarose , Extração em Fase Sólida , Ácidos Aristolóquicos/química , Ácidos Aristolóquicos/isolamento & purificação , Ácidos Aristolóquicos/sangue , Sefarose/química , Extração em Fase Sólida/métodos , Compostos de Amônio Quaternário/química , Cromatografia Líquida de Alta Pressão/métodos , Porosidade , Limite de Detecção , Animais , Humanos , Polímeros/química , Adsorção , Reprodutibilidade dos Testes
20.
ACS Appl Bio Mater ; 7(5): 3375-3387, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38693867

RESUMO

Encapsulation of natural polymer pectin (Pec) into a zeolitic imidazolate framework-12 (ZIF-12) matrix via a simple chemical method toward anticancer agent gallic acid (GA) detection is reported in this work. GA, a natural phenol found in many food sources, has gained attention by its biological effects on the human body, such as an antioxidant and anti-inflammatory. Therefore, it is crucial to accurately and rapidly determine the GA level in humans. The encapsulation of Pec inside the ZIF-12 has been successfully confirmed from the physiochemical studies such as XRD, Raman, FTIR, and XPS spectroscopy along with morphological FESEM, BET, and HRTEM characterization. Under optimized conditions, the Pec@ZIF-12 composite exhibits wide linear range of 20 nM-250 µM with a detection limit of 2.2 nM; also, it showed excellent selectivity, stability, and reproducibility. Furthermore, the real sample analysis of food samples including tea, coffee, grape, and pomegranate samples shows exceptional recovery percentage in an unspiked manner. So far, there is little literature for encapsulating proteins, enzymes, metals, etc., that have been reported; here, we successfully encapsulated a natural polymer Pec inside the ZIF-12 cage. This encapsulation significantly enhanced the composite electrochemical performance, which could be seen from the overall results. All of these strongly suggest that the proposed Pec@ZIF-12 composite could be used for miniaturized device fabrication for the evaluation of GA in both home and industrial applications.


Assuntos
Antineoplásicos , Técnicas Eletroquímicas , Imidazóis , Zeolitas , Zeolitas/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Imidazóis/química , Teste de Materiais , Ácido Gálico/química , Tamanho da Partícula , Materiais Biocompatíveis/química , Polímeros/química , Pectinas/química , Estruturas Metalorgânicas/química , Humanos
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