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1.
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
2.
Biosens Bioelectron ; 258: 116327, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38703496

RESUMO

Proper customization in size and shape is essential in implantable bioelectronics for stable bio-signal recording. Over the past decades, many researchers have heavily relied on conventional photolithography processes to fabricate implantable bioelectronics. Therefore, they could not avoid the critical limitation of high cost and complex processing steps to optimize bioelectronic devices for target organs with various sizes and shapes. Here, we propose rapid prototyping using all laser processes to fabricate customized bioelectronics. PEDOT:PSS is selectively irradiated by an ultraviolet (UV) pulse laser to form wet-stable conductive hydrogels that can softly interact with biological tissues (50 µm line width). The encapsulation layer is selectively patterned using the same laser source by UV-curing polymer networks (110 µm line width). For high stretchability (over 100%), mesh structures are made by the selective laser cutting process. Our rapid prototyping strategy minimizes the use of high-cost equipment, using only a single UV laser source to process the electrodes, encapsulation, and substrates that constitute bioelectronics without a photomask, enabling the prototyping stretchable microelectrode array with an area of 1 cm2 less than 10 min. We fabricated an optimized stretchable microelectrode array with low impedances (∼1.1 kΩ at 1 kHz) that can effectively record rat's cardiac signals with various health states.


Assuntos
Técnicas Biossensoriais , Condutividade Elétrica , Hidrogéis , Lasers , Hidrogéis/química , Animais , Técnicas Biossensoriais/instrumentação , Ratos , Polímeros/química , Desenho de Equipamento , Poliestirenos/química , Tiofenos
3.
AAPS PharmSciTech ; 25(5): 105, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724807

RESUMO

The formulation of microspheres involves a complex manufacturing process with multiple steps. Identifying the appropriate process parameters to achieve the desired quality attributes poses a significant challenge. This study aims to optimize the critical process parameters (CPPs) involved in the preparation of naltrexone microspheres using a Quality by Design (QbD) methodology. Additionally, the research aims to assess the drug release profiles of these microspheres under both in vivo and in vitro conditions. Critical process parameters (CPPs) and critical quality attributes (CQAs) were identified, and a Box-Behnken design was utilized to delineate the design space, ensuring alignment with the desired Quality Target Product Profile (QTPP). The investigated CPPs comprised polymer concentration, aqueous phase ratio to organic phase ratio, and quench volume. The microspheres were fabricated using the oil-in-water emulsion solvent extraction technique. Analysis revealed that increased polymer concentration was correlated with decreased particle size, reduced quench volume resulted in decreased burst release, and a heightened aqueous phase ratio to organic phase ratio improved drug entrapment. Upon analyzing the results, an optimal formulation was determined. In conclusion, the study conducted in vivo drug release testing on both the commercially available innovator product and the optimized test product utilizing an animal model. The integration of in vitro dissolution data with in vivo assessments presents a holistic understanding of drug release dynamics. The QbD approach-based optimization of CPPs furnishes informed guidance for the development of generic pharmaceutical formulations.


Assuntos
Química Farmacêutica , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Microesferas , Naltrexona , Tamanho da Partícula , Naltrexona/química , Naltrexona/administração & dosagem , Naltrexona/farmacocinética , Animais , Química Farmacêutica/métodos , Preparações de Ação Retardada/química , Sistemas de Liberação de Medicamentos/métodos , Polímeros/química , Emulsões/química , Composição de Medicamentos/métodos , Solubilidade , Solventes/química
4.
Molecules ; 29(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731481

RESUMO

As the use of antibiotics increases, the increasing resistance of bacteria is the main reason for the reduced efficiency of antibacterial drugs, making the research of new antibacterial materials become new hot spot. In this article, two novel coordination polymers (CPs), namely, [Cd2(L)2(bibp)2]n (1) and [Ni(L)(bib)]n (2), where H2L = N,N'-bis(4-carbozvlbenzvl)-4-aminotoluene, bibp = 4,4'-bis(imidazol-1-yl)biphenyl, and bib = 1,3-bis(1-imidazoly)benzene, have been synthesized under solvothermal and hydrothermal condition. Structural clarification was performed through infrared spectrum and single-crystal X-ray diffraction analysis, while thermal analysis and XRD technology were used for the performance assessment of compounds 1 and 2. In addition, antibacterial performance experiments showed that compounds 1 and 2 have certain selectivity in their antibacterial properties and have good antibacterial properties against S. aureus. As the concentration of the compound increases, the inhibitory effect gradually strengthens, and when the concentration of the compound reaches 500 µg/mL and 400 µg/mL, the concentration of the S. aureus solution no longer increases and has been completely inhibited.


Assuntos
Antibacterianos , Testes de Sensibilidade Microbiana , Polímeros , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Staphylococcus aureus/efeitos dos fármacos , Polímeros/química , Polímeros/farmacologia , Polímeros/síntese química , Ligantes , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Estrutura Molecular , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Compostos Heterocíclicos/síntese química , Modelos Moleculares , Cristalografia por Raios X
5.
Molecules ; 29(9)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38731542

RESUMO

Bilayer electrospun fibers aimed to be used for skin tissue engineering applications were fabricated for enhanced cell attachment and proliferation. Different ratios of PHBV-PLLA (70:30, 80:20, and 90:10 w/w) blends were electrospun on previously formed electrospun PHBV membranes to produce their bilayers. The fabricated electrospun membranes were characterized with FTIR, which conformed to the characteristic peaks assigned for both PHBV and PLLA. The surface morphology was evaluated using SEM analysis that showed random fibers with porous morphology. The fiber diameter and pore size were measured in the range of 0.7 ± 0.1 µm and 1.9 ± 0.2 µm, respectively. The tensile properties of the bilayers were determined using an electrodynamic testing system. Bilayers had higher elongation at break (44.45%) compared to the monolayers (28.41%) and improved ultimate tensile strength (7.940 MPa) compared to the PHBV monolayer (2.450 MPa). In vitro cytotoxicity of each of the scaffolds was determined via culturing MC3T3 (pre-osteoblastic cell line) on the membranes. Proliferation was evaluated using the Alamar Blue assay on days 3, 7, and 14, respectively. SEM images of cells cultured on membranes were taken in addition to bright field imaging to visually show cell attachment. Fluorescent nuclear staining performed with DAPI was imaged with an inverted fluorescent microscope. The fabricated bilayer shows high mechanical strength as well as biocompatibility with good cell proliferation and cell attachment, showing potential for skin substitute applications.


Assuntos
Materiais Biocompatíveis , Proliferação de Células , Poliésteres , Pele , Engenharia Tecidual , Alicerces Teciduais , Engenharia Tecidual/métodos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Poliésteres/química , Animais , Camundongos , Proliferação de Células/efeitos dos fármacos , Alicerces Teciduais/química , Resistência à Tração , Membranas Artificiais , Linhagem Celular , Teste de Materiais , Polímeros/química , Adesão Celular/efeitos dos fármacos
6.
Sci Rep ; 14(1): 10798, 2024 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734777

RESUMO

The nucleation of carbonate-containing apatite on the biomaterials surface is regarded as a significant stage in bone healing process. In this regard, composites contained hydroxyapatite (Ca10(PO4)6(OH)2, HA), wollastonite (CaSiO3, WS) and polyethersulfone (PES) were synthesized via a simple solvent casting technique. The in-vitro bioactivity of the prepared composite films with different weight ratios of HA and WS was studied by placing the samples in the simulated body fluid (SBF) for 21 days. The results indicated that the the surface of composites containing 2 wt% HA and 4 wt% WS was completely covered by a thick bone-like apatite layer, which was characterized by Grazing incidence X-ray diffraction, attenuated total reflectance-Fourier transform infrared spectrometer, field emission electron microscopy and energy dispersive X-ray analyzer (EDX). The degradation study of the samples showed that the concentration of inorganic particles could not influence the degradability of the polymeric matrix, where all samples expressed similar dexamethasone (DEX) release behavior. Moreover, the in-vitro cytotoxicity results indicated the significant cyto-compatibility of all specimens. Therefore, these findings revealed that the prepared composite films composed of PES, HA, WS and DEX could be regarded as promising bioactive candidates with low degradation rate for bone tissue engineering applications.


Assuntos
Materiais Biocompatíveis , Substitutos Ósseos , Durapatita , Nanocompostos , Silicatos , Durapatita/química , Nanocompostos/química , Substitutos Ósseos/química , Substitutos Ósseos/farmacologia , Silicatos/química , Materiais Biocompatíveis/química , Compostos de Cálcio/química , Liberação Controlada de Fármacos , Dexametasona/química , Dexametasona/farmacologia , Polímeros/química , Humanos , Difração de Raios X , Teste de Materiais , Espectroscopia de Infravermelho com Transformada de Fourier , Animais
8.
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
9.
Mikrochim Acta ; 191(6): 306, 2024 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713247

RESUMO

For early diabetes identification and management, the progression of an uncomplicated and exceedingly responsive glucose testing technology is crucial. In this study, we present a new sensor incorporating a composite of metal organic framework (MOF) based on cobalt, coated with boronic acid to facilitate selective glucose binding. Additionally, we successfully employed a highly sensitive electro-optical immunosensor for the detection of subtle changes in concentration of the diabetes biomarker glycated haemoglobin (HbA1c), using zeolitic imidazolate framework-67 (ZIF-67) coated with polydopamine which further modified with boronic acid. Utilizing the polymerization characteristics of dopamine and the NH2 groups, a bonding structure is formed between ZIF-67 and 4-carboxyphenylboronic acid. ZIF-67 composite served as an effective substrate for immobilising 4-carboxyphenylboronic acid binding agent, ensuring precise and highly selective glucose identification. The sensing response was evaluated through both electrochemical and optical methods, confirming its efficacy. Under optimized experimental condition, the ZIF-67 based sensor demonstrated a broad detection range of 50-500 mg dL-1, a low limit of detection (LOD) of 9.87 mg dL-1 and a high correlation coefficient of 0.98. Furthermore, the 4-carboxyphenylboronic acid-conjugated ZIF-67-based sensor platform exhibited remarkable sensitivity and selectivity in optical-based detection for glycated haemoglobin within the clinical range of 4.7-11.3%, achieving a LOD of 3.7%. These findings highlight the potential of the 4-carboxyphenylboronic acid-conjugated ZIF-67-based electro-optical sensor as a highly sensitive platform for diabetes detection.


Assuntos
Glicemia , Ácidos Borônicos , Diabetes Mellitus , Hemoglobinas Glicadas , Imidazóis , Limite de Detecção , Estruturas Metalorgânicas , Zeolitas , Ácidos Borônicos/química , Zeolitas/química , Estruturas Metalorgânicas/química , Imidazóis/química , Humanos , Hemoglobinas Glicadas/análise , Glicemia/análise , Diabetes Mellitus/sangue , Diabetes Mellitus/diagnóstico , Nanopartículas/química , Técnicas Biossensoriais/métodos , Indóis/química , Polímeros/química , Técnicas Eletroquímicas/métodos
10.
PLoS One ; 19(5): e0303096, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38713656

RESUMO

Fast-growing poplar plantations are considered a great benefit to timber production, but water availability is a key factor limiting their growth and development, especially in arid and semi-arid ecosystems. Super-absorbent polymers facilitate more water retention in soil after rain or irrigation, and they are able to release water gradually during plant growth. This study aimed to examine the effects of reduced irrigation (60% and 30% of conventional border irrigation) co-applied with super-absorbent polymers (0, 40 kg/ha) on root exudates, enzyme activities, microbial functional diversity in rhizosphere soil, and volume increments in poplar (Populus euramericana cv. 'Neva'). The results showed that 60% border irrigation co-applied with super-absorbent polymers significantly increased the content of organic acids, amino acids and total sugars in the root exudates, and the activities of invertase, urease, dehydrogenase, and catalase in the rhizosphere soil in comparison to conventional border irrigation without super-absorbent polymers. Meanwhile, this treatment also enhanced the average well-color development, Shannon index, and McIntosh index, but decreased the Simpson index. Additionally, the average volume growth rate and relative water content of leaves reached their maximum using 60% irrigation with super-absorbent polymers, which was significantly higher than other treatments. However, using 30% irrigation with super-absorbent polymers, had a smaller effect on rhizosphere soil and volume growth than 60% irrigation with super-absorbent polymers. Therefore, using an appropriate water-saving irrigation measure (60% conventional border irrigation with super-absorbent polymers) can help to improve enzyme activities and microbial diversity in the rhizosphere soil while promoting the growth of poplar trees.


Assuntos
Irrigação Agrícola , Polímeros , Populus , Rizosfera , Microbiologia do Solo , Populus/crescimento & desenvolvimento , Populus/microbiologia , Irrigação Agrícola/métodos , Polímeros/química , Raízes de Plantas/microbiologia , Raízes de Plantas/crescimento & desenvolvimento , Solo/química , Água/química
11.
Anal Chim Acta ; 1307: 342645, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719410

RESUMO

Electrochemical biosensors with high sensitivity can detect low concentrations of biomarkers, but their practical detection applications in complex biological environments such as human serum and sweat are severely limited by the biofouling. Herein, a conductive hydrogel based on bovine serum albumin (BSA) and conductive carbon black (CCB) was prepared for the construction of an antifouling biosensor. The BSA hydrogel (BSAG) was doped with CCB, and the prepared composite hydrogel exhibited good conductivity originated from the CCB and antifouling capability owing to the BSA hydrogel. An antifouling biosensor for the sensitive detection of cortisol was fabricated by drop-coating the conductive hydrogel onto a poly(3,4-ethylenedioxythiophene) (PEDOT) modified electrode and further immobilizing the cortisol aptamer. The constructed biosensor showed a linear range of 100 pg mL-1 - 10 µg mL-1 and a limit of detection of 26.0 pg mL-1 for the detection of cortisol, and it was capable of assaying cortisol accurately in complex human serum. This strategy of preparing antifouling and conductive hydrogels provides an effective way to develop robust electrochemical biosensors for biomarker detection in complex biological media.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Hidrocortisona , Hidrogéis , Soroalbumina Bovina , Fuligem , Humanos , Técnicas Biossensoriais/métodos , Soroalbumina Bovina/química , Hidrocortisona/sangue , Hidrocortisona/análise , Fuligem/química , Técnicas Eletroquímicas/métodos , Hidrogéis/química , Bovinos , Incrustação Biológica/prevenção & controle , Limite de Detecção , Animais , Eletrodos , Aptâmeros de Nucleotídeos/química , Polímeros , Compostos Bicíclicos Heterocíclicos com Pontes
12.
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
13.
Int J Mol Sci ; 25(9)2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38732243

RESUMO

This study presents the functionalization of silk fabric with SWCNT ink. The first step was the formation of a polydopamine (PDA) thin coating on the silk fabric to allow for effective bonding of SWCNTs. PDA formation was carried out directly on the fabric by means of polymerization of dopamine in alkali conditions. The Silk/PDA fabric was functionalized with SWCNT ink of different SWCNT concentrations by using the dip-coating method. IR and Raman analyses show that the dominant ß-sheet structure of silk fibroin after the functionalization process remains unchanged. The heat resistance is even slightly improved. The hydrophobic silk fabric becomes hydrophilic after functionalization due to the influence of PDA and the surfactant in SWCNT ink. The ink significantly changes the electrical properties of the silk fabric, from insulating to conductive. The volume resistance changes by nine orders of magnitude, from 2.4 × 1012 Ω to 2.3 × 103 Ω for 0.12 wt.% of SWCNTs. The surface resistance changes by seven orders of magnitude, from 2.1 × 1012 Ω to 2.4 × 105 Ω for 0.17 wt.% of SWCNTs. The volume and surface resistance thresholds are determined to be about 0.05 wt.% and 0.06 wt.%, respectively. The low value of the percolation threshold indicates efficient functionalization, with high-quality ink facilitating the formation of percolation paths through SWCNTs and the influence of the PDA linker.


Assuntos
Condutividade Elétrica , Indóis , Tinta , Nanotubos de Carbono , Polímeros , Seda , Indóis/química , Polímeros/química , Seda/química , Nanotubos de Carbono/química , Têxteis , Interações Hidrofóbicas e Hidrofílicas
14.
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
15.
Sensors (Basel) ; 24(9)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38733009

RESUMO

Recent advancements in polymer-assisted layer-by-layer (LbL) fabrication have revolutionized the development of wearable sensors for health monitoring. LbL self-assembly has emerged as a powerful and versatile technique for creating conformal, flexible, and multi-functional films on various substrates, making it particularly suitable for fabricating wearable sensors. The incorporation of polymers, both natural and synthetic, has played a crucial role in enhancing the performance, stability, and biocompatibility of these sensors. This review provides a comprehensive overview of the principles of LbL self-assembly, the role of polymers in sensor fabrication, and the various types of LbL-fabricated wearable sensors for physical, chemical, and biological sensing. The applications of these sensors in continuous health monitoring, disease diagnosis, and management are discussed in detail, highlighting their potential to revolutionize personalized healthcare. Despite significant progress, challenges related to long-term stability, biocompatibility, data acquisition, and large-scale manufacturing are still to be addressed, providing insights into future research directions. With continued advancements in polymer-assisted LbL fabrication and related fields, wearable sensors are poised to improve the quality of life for individuals worldwide.


Assuntos
Técnicas Biossensoriais , Polímeros , Dispositivos Eletrônicos Vestíveis , Polímeros/química , Humanos , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos
16.
Sensors (Basel) ; 24(9)2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38733034

RESUMO

INTRODUCTION: The choice of materials for covering plantar orthoses or wearable insoles is often based on their hardness, breathability, and moisture absorption capacity, although more due to professional preference than clear scientific criteria. An analysis of the thermal response to the use of these materials would provide information about their behavior; hence, the objective of this study was to assess the temperature of three lining materials with different characteristics. MATERIALS AND METHODS: The temperature of three materials for covering plantar orthoses was analyzed in a sample of 36 subjects (15 men and 21 women, aged 24.6 ± 8.2 years, mass 67.1 ± 13.6 kg, and height 1.7 ± 0.09 m). Temperature was measured before and after 3 h of use in clinical activities, using a polyethylene foam copolymer (PE), ethylene vinyl acetate (EVA), and PE-EVA copolymer foam insole with the use of a FLIR E60BX thermal camera. RESULTS: In the PE copolymer (material 1), temperature increases between 1.07 and 1.85 °C were found after activity, with these differences being statistically significant in all regions of interest (p < 0.001), except for the first toe (0.36 °C, p = 0.170). In the EVA foam (material 2) and the expansive foam of the PE-EVA copolymer (material 3), the temperatures were also significantly higher in all analyzed areas (p < 0.001), ranging between 1.49 and 2.73 °C for EVA and 0.58 and 2.16 °C for PE-EVA. The PE copolymer experienced lower overall overheating, and the area of the fifth metatarsal head underwent the greatest temperature increase, regardless of the material analyzed. CONCLUSIONS: PE foam lining materials, with lower density or an open-cell structure, would be preferred for controlling temperature rise in the lining/footbed interface and providing better thermal comfort for users. The area of the first toe was found to be the least overheated, while the fifth metatarsal head increased the most in temperature. This should be considered in the design of new wearables to avoid excessive temperatures due to the lining materials.


Assuntos
Órtoses do Pé , Temperatura , Humanos , Feminino , Masculino , Adulto , Adulto Jovem , Polivinil/química , Polietileno/química , Polímeros/química , Teste de Materiais
17.
Nanomedicine ; 55: 102716, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38738529

RESUMO

Rheumatoid arthritis is a chronic inflammatory autoimmune disease caused by alteration of the immune system. Current therapies have several limitations and the use of nanomedicines represents a promising strategy to overcome them. By employing a mouse model of adjuvant induced arthritis, we aimed to evaluate the biodistribution and therapeutic effects of glucocorticoid dexamethasone conjugated to a nanocarrier based on biocompatible N-(2-hydroxypropyl) methacrylamide copolymers. We observed an increased accumulation of dexamethasone polymer nanomedicines in the arthritic mouse paw using non-invasive fluorescent in vivo imaging and confirmed it by the analysis of tissue homogenates. The dexamethasone conjugate exhibited a dose-dependent healing effect on arthritis and an improved therapeutic outcome compared to free dexamethasone. Particularly, significant reduction of accumulation of RA mediator RANKL was observed. Overall, our data suggest that the conjugation of dexamethasone to a polymer nanocarrier by means of stimuli-sensitive spacer is suitable strategy for improving rheumatoid arthritis therapy.


Assuntos
Artrite Reumatoide , Dexametasona , Polímeros , Animais , Dexametasona/química , Dexametasona/farmacocinética , Dexametasona/administração & dosagem , Dexametasona/farmacologia , Dexametasona/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/patologia , Camundongos , Distribuição Tecidual , Polímeros/química , Polímeros/farmacocinética , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Nanopartículas/química , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética
18.
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
19.
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
20.
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
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