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1.
Food Res Int ; 188: 114442, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823830

RESUMO

The long-term stability of red wine color depends on the formation of polymeric pigments from anthocyanins. Although there is still a lot of uncertainty about the specific structure of this diverse group of pigments, there is consensus that they are reaction products of anthocyanins and other polyphenols. Interactions between anthocyanins and pectic polysaccharides have been suggested to stabilize anthocyanins. This study explores the impact of such interactions by adding pectin during red winemaking. The results demonstrate that these interactions induce the formation of additional polymeric pigments which enhance the pigment stability during fermentation and aging. While initial pigment formation is higher in wines with added pectin, a notable proportion of the complexes degrades in the later stages of fermentation. Presumably, tannins form insoluble complexes with pectin, reducing tannin concentration by more than 300 mg/L. Anthocyanin concentrations decrease by over 400 mg/L, and polymeric pigments double. Anthocyanins that form polymeric pigments with pectic polysaccharides expand the range of pigments in red wines with possible consequences for the sensory properties of the wine. These findings highlight the complex interactions between pectin, anthocyanins, and tannins, and their influence on pigment formation and wine composition during fermentation and aging.


Assuntos
Antocianinas , Fermentação , Pectinas , Taninos , Vinho , Antocianinas/química , Antocianinas/análise , Pectinas/química , Vinho/análise , Taninos/química , Cor , Manipulação de Alimentos/métodos , Pigmentos Biológicos/química , Polímeros/química
2.
Top Curr Chem (Cham) ; 382(2): 21, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829461

RESUMO

The molecular design and conformations of hole-transporting materials (HTM) have unravelled a strategy to enhance the performance of environmentally sustainable perovskite solar cells (PSC). Several attempts have been made and several are underway for improving the efficiency of PSCs by designing an efficient HTM, which is crucial to preventing corrosion, facilitating effective hole transportation, and preventing charge recombination. There is a need for a potential alternative to the current market-dominating HTM due to its high cost of production, dopant requirements, moisture sensitivity, and low stability. Among several proposed HTMs, molecules derived from thiophene exhibit unique behaviour, such as the interaction with under-coordinated Pb2+, thereby facilitating the passivation of surface defects in the perovskite layer. In addition, coupling a suitable side chain imparts a hydrophobic character, eventually leading to the development of a moisture-sensitive and highly stable PSC. Furthermore, thiophene-backboned polymers with ionic pendants have been employed as an interfacial layer between PSC layers, with the backbone facilitating efficient charge transfer. This perspective article comprehensively presents the design strategy, characterization, and function of HTMs associated with thiophene-derived molecules. Hence, it is observed that thiophene-formulated HTMs have an enhanced passivation effect, good performance in an open-circuit environment, longevity, humidity resistance, thermostability, good hole extraction, and mobility in a dopant-free condition. For a better understanding, the article provides a comparative description of the activity and function of thiophene-based small molecules and polymers and their effect on device performance.


Assuntos
Compostos de Cálcio , Óxidos , Energia Solar , Tiofenos , Titânio , Tiofenos/química , Compostos de Cálcio/química , Titânio/química , Óxidos/química , Fontes de Energia Elétrica , Polímeros/química
3.
Carbohydr Polym ; 339: 122261, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823925

RESUMO

Understanding the distribution and accessibility of polymers within plant cell walls is crucial for addressing biomass recalcitrance in lignocellulosic materials. In this work, Imaging Fourier Transform Infrared (FTIR) and Raman spectroscopy, coupled with targeted chemical treatments, were employed to investigate cell wall polymer distribution in two bamboo species at both tissue and cell wall levels. Tissue-level Imaging FTIR revealed significant disparities in the distribution and chemical activity of cell wall polymers between the fibrous sheath and fibrous strand. At the cell wall level, Imaging Raman spectroscopy delineated a distinct difference between the secondary wall and intercellular layer, with the latter containing higher levels of lignin, hydroxycinnamic acid (HCA), and xylan, and lower cellulose. Mild acidified sodium chlorite treatment led to partial removal of lignin, HCA, and xylan from the intercellular layer, albeit to a lesser extent than alkaline treatment, indicating susceptibility of these polymers to chemical treatment. In contrast, lignin in the secondary wall exhibited limited reactivity to acidified sodium chlorite but was slightly removed by alkaline treatment, suggesting stable chemical properties with slight alkaline intolerance. These findings provide valuable insights into the inherent design mechanism of plant cells and their efficient utilization.


Assuntos
Parede Celular , Celulose , Ácidos Cumáricos , Lignina , Parede Celular/química , Lignina/química , Ácidos Cumáricos/química , Celulose/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Xilanos/química , Análise Espectral Raman/métodos , Sasa/química , Cloretos/química , Polímeros/química
4.
Carbohydr Polym ; 339: 122257, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823923

RESUMO

Traditional solid phase extraction (SPE) suffers from a lack of specific adsorption. To overcome this problem, a combination of adsorption method and molecular imprinting technology by polydopamine modification was proposed to realize specific recognition of target compounds in SPE, which is of great significance to improve the separation efficiency of SPE. Cellulose hydrogel beads were prepared by dual cross-linking curing method and modified with polydopamine to make them hydrophilic and biocompatible. Subsequently, cellulose hydrogel-based molecularly imprinted beads (MIBs) were synthesized by surface molecular imprinting technology and used as novel column fillers in SPE to achieve efficient adsorption (34.16 mg·g-1) with specific selectivity towards camptothecin (CPT) in 120 min. The simulation and NMR analysis revealed that recognition mechanism of MIBs involved hydrogen bond interactions and Van der Waals effect. The MIBs were successful used in separating CPT from Camptotheca acuminata fruits, exhibiting impressive adsorption capacity (1.19 mg·g-1) and efficient recovery of CPT (81.54 %). Thus, an environmentally friendly column filler for SPE was developed, offering a promising avenue for utilizing cellulose-based materials in the selective separation of natural products.


Assuntos
Camptotecina , Celulose , Hidrogéis , Impressão Molecular , Extração em Fase Sólida , Camptotecina/química , Camptotecina/isolamento & purificação , Celulose/química , Adsorção , Impressão Molecular/métodos , Hidrogéis/química , Extração em Fase Sólida/métodos , Camptotheca/química , Polímeros/química , Interações Hidrofóbicas e Hidrofílicas , Indóis/química , Frutas/química
5.
Anal Chim Acta ; 1312: 342742, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38834261

RESUMO

Hyperuricemia (HUA) has gradually become a public health burden as an independent risk factor for a variety of chronic diseases. Herein, a user-friendly point-of-care (POC) detection system (namely "Smart-HUA-Monitor") based on smartphone-assisted paper-based microfluidic is proposed for colorimetric quantification of HUA urinary markers, including uric acid (UA), creatinine (CR) and pH. The detection limits of UA and CR were 0.0178 and 0.5983 mM, respectively, and the sensitivity of pH were 0.1. The method was successfully validated in artificial urine samples and 100 clinical samples. Bland-Altman plots showed a high consistency between µPAD and the testing instruments (HITACHI 7600 Automatic Analyzer, URIT-500B Urine Analyzer and AU5800B automatic biochemical analyzer) in hospital. Smart-HUA-Monitor provides an accurate quantitative, rapid, low-cost and reliable tool for the monitoring and early diagnosis of HUA urine indicators.


Assuntos
Colorimetria , Hiperuricemia , Papel , Polímeros , Ácido Úrico , Humanos , Hiperuricemia/diagnóstico , Hiperuricemia/urina , Polímeros/química , Ácido Úrico/urina , Colorimetria/instrumentação , Dispositivos Lab-On-A-Chip , Smartphone , Creatinina/urina , Técnicas Analíticas Microfluídicas/instrumentação , Limite de Detecção , Biomarcadores/urina , Concentração de Íons de Hidrogênio
6.
Anal Chim Acta ; 1312: 342762, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38834277

RESUMO

Mucin1 (MUC1) is an extensively glycosylated transmembrane protein that is widely distributed and overexpressed on the surface of cancer cells, playing an important role in tumor occurrence and metastasis. Therefore, highly sensitive detection of MUC1 is of great significance for early diagnosis, treatment monitoring, and prognosis of cancer. Here, an ultra-sensitive photoelectrochemical (PEC) sensing platform was developed based on an aptamer amplification strategy for highly selective and sensitive detection of MUC1 overexpressed in serum and on cancer cell surfaces. The sensing platform utilized copper phthalocyanine to fabricate porous organic polymers (CuPc POPs), and was effectively integrated with g-C3N4/MXene to form a ternary heterojunction material (g-C3N4/MXene/CuPc POPs). This material effectively improved electron transfer capability, significantly enhanced light utilization, and greatly enhanced photoelectric conversion efficiency, resulting in a dramatic increase in photocurrent response. MUC1 aptamer 1 was immobilized on a chitosan-modified photoelectrode for the selective capture of MUC1 or MCF-7 cancer cells. When the target substance was present, MUC1 aptamer 2 labeled with methylene blue (MB) was specifically adsorbed on the electrode surface, leading to enhanced photocurrent. The concentration of MUC1 directly correlated with the number of MB molecules attracted to the electrode surface, establishing a linear relationship between photocurrent intensity and MUC1 concentration. The PEC biosensor exhibited excellent sensitivity for MUC1 detection with a wide detection range from 1 × 10-7 to 10 ng/mL and a detection limit of 8.1 ag/mL. The detection range for MCF-7 cells was from 2 × 101 to 2 × 106 cells/mL, with the capability for detecting single MCF-7 cells. The aptamer amplification strategy significantly enhanced PEC performance, and open up a promising platform to establish high selectivity, stability, and ultrasensitive analytical techniques.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Eletroquímicas , Mucina-1 , Polímeros , Mucina-1/análise , Humanos , Aptâmeros de Nucleotídeos/química , Técnicas Eletroquímicas/métodos , Células MCF-7 , Porosidade , Polímeros/química , Limite de Detecção , Técnicas Biossensoriais/métodos , Indóis/química , Processos Fotoquímicos , Compostos Organometálicos/química
7.
PLoS One ; 19(6): e0303900, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38843120

RESUMO

BACKGROUND: Candesartan cilexetil (CC) is a selective angiotensin II receptor antagonist widely used to treat hypertension. CC is a substrate of P-glycoprotein (P-gp), causing its efflux to the intestinal lumen. It is also practically insoluble in water and has low oral bioavailability (14%). Thus, the current study aims to improve the in vitro dissolution of CC by developing solid dispersion systems (SDSs) and corroborating the in vitro results using a simulated pharmacokinetics study. METHODS: The SDSs were prepared using polyvinyl pyrrolidone (PVP) as a water-soluble polymer, Eudragit E100 (EE100) as a pH-dependent soluble carrier, and a combination of these two polymers. The saturation solubility and the dissolution rate studies of the prepared systems in three dissolution media were performed. The optimized system SE-EE5 was selected for further investigations, including DSC, XRD, FTIR, FESEM, DLS, TSEM, IVIVC convolution study, and stability studies. RESULTS: The solubility of CC significantly increased by a factor of 27,037.344 when formulated as a solid dispersion matrix using EE100 at a ratio of 1:5 (w/w) drug to polymer (SE-EE5 SD), compared to the solubility of the pure drug. The mechanism of solubility and dissolution rate enhancement of CC by the optimized SDS was found to be via the conversion of the crystalline CC into the amorphous form as well as nanoparticles formation upon dissolution at a pH below 5. The instrumental analysis tests showed good compatibility between CC and EE100 and there was no chemical interaction between the drug and the polymer. Moreover, the stability tests confirmed that the optimized system was stable after three months of storage at 25°C. CONCLUSION: The utilization of the solid dispersion technique employing EE 100 polymer as a matrix demonstrates significant success in enhancing the solubility, dissolution, and subsequently, the bioavailability of water-insoluble drugs like CC.


Assuntos
Benzimidazóis , Compostos de Bifenilo , Polímeros , Solubilidade , Tetrazóis , Benzimidazóis/química , Benzimidazóis/farmacocinética , Tetrazóis/química , Tetrazóis/farmacocinética , Compostos de Bifenilo/química , Compostos de Bifenilo/farmacocinética , Polímeros/química , Polímeros/farmacocinética , Povidona/química , Água/química , Concentração de Íons de Hidrogênio , Disponibilidade Biológica , Estabilidade de Medicamentos , Liberação Controlada de Fármacos , Acrilatos
8.
AAPS PharmSciTech ; 25(5): 130, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844611

RESUMO

Naringenin (NRG) inhibits the fungal 17ß-hydroxysteroid dehydrogenase accountable for ergosterol synthesis in Candida albicans (C. albicans), a causative agent for cutaneous candidiasis. In present research, NRG was complexed with ZnO nanomaterial (NRG-Zn2+) to synthesize NRG-Zn2+ nanocomposites. The particle size and ζ-potential of NRG-Zn2+ nanocomposites were respectively estimated to be 180.33 ± 1.22-nm and - 3.92 ± 0.35-mV. In silico data predicted the greater affinity of NRG-Zn2+ nanocomposite for 14α-demethylase and ceramide in comparison to NRG alone. Later, NRG-Zn2+ nanocomposites solution was transformed in to naringenin-zinc oxide nanocomposites loaded chitosan gel (NRG-Zn-CS-Gel) with viscosity and firmness of 854806.7 ± 52386.43 cP and 698.27 ± 10.35 g, respectively. The ex-vivo skin permeation demonstrated 70.49 ± 5.22% skin retention, significantly greater (P < 0.05) than 44.48 ± 3.06% of naringenin loaded chitosan gel (NRG-CS-Gel) and 31.24 ± 3.28% of naringenin solution (NRG Solution). NRG-Zn-CS-Gel demonstrated 6.71 ± 0.84% permeation of NRG with a flux value of 0.046 ± 0.01-µg/cm2/h. The MIC50 of NRG-Zn-CS-Gel against C. albicans was estimated to be 0.156-µg/mL with FICI (fractional inhibitory concentration index) of 0.018 that consequently exhibited synergistic efficacy. Further, NRG-Zn-CS-Gel demonstrated superior antifungal efficacy in C. albicans induced cutaneous candidiasis infection in Balb/c mice. The fungal burden in NRG-Zn-CS-Gel treated group was 109 ± 25 CFU/mL, significantly lower (P < 0.05) than positive control (2260 ± 446 CFU/mL), naringenin loaded chitosan gel (NRG-CS-Gel; 928 ± 127 CFU/mL) and chitosan gel (CS-Gel; 2116 ± 186 CFU/mL) treated mice. Further, histopathology examination and cytokine profiling of TNF-α, IL-1ß and IL-10 revealed the healing of skin and inflammation associated with cutaneous candidiasis infection. In conclusion, NRG-Zn-CS-Gel may be a potential candidate for translating in to a clinical viable topical nanotherapeutic.


Assuntos
Antifúngicos , Candida albicans , Quitosana , Flavanonas , Géis , Camundongos Endogâmicos BALB C , Nanocompostos , Óxido de Zinco , Animais , Flavanonas/administração & dosagem , Flavanonas/farmacologia , Camundongos , Candida albicans/efeitos dos fármacos , Quitosana/química , Quitosana/administração & dosagem , Nanocompostos/química , Nanocompostos/administração & dosagem , Antifúngicos/administração & dosagem , Antifúngicos/farmacologia , Antifúngicos/farmacocinética , Óxido de Zinco/administração & dosagem , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Sistemas de Liberação de Medicamentos/métodos , Pele/metabolismo , Pele/efeitos dos fármacos , Pele/microbiologia , Candidíase/tratamento farmacológico , Polímeros/química , Absorção Cutânea/efeitos dos fármacos , Tamanho da Partícula , Administração Cutânea
9.
AAPS PharmSciTech ; 25(5): 127, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844724

RESUMO

The success of obtaining solid dispersions for solubility improvement invariably depends on the miscibility of the drug and polymeric carriers. This study aimed to categorize and select polymeric carriers via the classical group contribution method using the multivariate analysis of the calculated solubility parameter of RX-HCl. The total, partial, and derivate parameters for RX-HCl were calculated. The data were compared with the results of excipients (N = 36), and a hierarchical clustering analysis was further performed. Solid dispersions of selected polymers in different drug loads were produced using solvent casting and characterized via X-ray diffraction, infrared spectroscopy and scanning electron microscopy. RX-HCl presented a Hansen solubility parameter (HSP) of 23.52 MPa1/2. The exploratory analysis of HSP and relative energy difference (RED) elicited a classification for miscible (n = 11), partially miscible (n = 15), and immiscible (n = 10) combinations. The experimental validation followed by a principal component regression exhibited a significant correlation between the crystallinity reduction and calculated parameters, whereas the spectroscopic evaluation highlighted the hydrogen-bonding contribution towards amorphization. The systematic approach presented a high discrimination ability, contributing to optimal excipient selection for the obtention of solid solutions of RX-HCl.


Assuntos
Química Farmacêutica , Excipientes , Polímeros , Cloridrato de Raloxifeno , Solubilidade , Difração de Raios X , Polímeros/química , Excipientes/química , Cloridrato de Raloxifeno/química , Análise Multivariada , Difração de Raios X/métodos , Química Farmacêutica/métodos , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Microscopia Eletrônica de Varredura/métodos , Ligação de Hidrogênio , Cristalização/métodos
10.
Eur Phys J E Soft Matter ; 47(6): 37, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829453

RESUMO

In this study, we demonstrate the fabrication of polymersomes, protein-blended polymersomes, and polymeric microcapsules using droplet microfluidics. Polymersomes with uniform, single bilayers and controlled diameters are assembled from water-in-oil-in-water double-emulsion droplets. This technique relies on adjusting the interfacial energies of the droplet to completely separate the polymer-stabilized inner core from the oil shell. Protein-blended polymersomes are prepared by dissolving protein in the inner and outer phases of polymer-stabilized droplets. Cell-sized polymeric microcapsules are assembled by size reduction in the inner core through osmosis followed by evaporation of the middle phase. All methods are developed and validated using the same glass-capillary microfluidic apparatus. This integrative approach not only demonstrates the versatility of our setup, but also holds significant promise for standardizing and customizing the production of polymer-based artificial cells.


Assuntos
Células Artificiais , Polímeros , Células Artificiais/química , Polímeros/química , Polímeros/síntese química , Emulsões/química , Cápsulas/química , Microfluídica/métodos , Água/química , Técnicas Analíticas Microfluídicas , Proteínas/química
11.
PLoS One ; 19(6): e0304797, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38829883

RESUMO

Partially encased concrete (PEC) has better mechanical properties as a structure where steel and concrete work together. Due to the increasing amount of construction waste, recycled aggregate concrete (RAC) is being considered by more people. However, although RAC has more points, the performance is inferior to natural aggregate concrete (NAC). To narrow or address this gap, lightweight, high-strength and corrosion-resistant CFRP can be used, also protecting the steel flange of the PEC structure. Therefore, carbon fiber reinforced polymer (CFRP) confined partially encased recycled coarse aggregate concrete columns were studied in this paper. With respect to different slenderness ratios, recycled coarse aggregate(RCA) replacement ratios, and number of CFRP layers, the performance of the proposed CFRP restrained columns are reported. The RCA replacement ratio is analyzed to be limited negative impact on the bearing capacity, generally within 6%. As for the slenderness ratio, the bearing capacity increased with it. However, wrapping CFRP significantly increased the bearing capacity. Considering the arch factor, a simple formula for calculating the ultimate strength of CFRP-confined partially encased RAC columns is developed based on EC4 and GB50017-2017. By comparison with the experimental values, the error is within 10%.


Assuntos
Fibra de Carbono , Força Compressiva , Materiais de Construção , Polímeros , Reciclagem , Fibra de Carbono/química , Materiais de Construção/análise , Polímeros/química , Teste de Materiais , Aço/química
12.
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
13.
Colloids Surf B Biointerfaces ; 238: 113928, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38692175

RESUMO

In this research, four water-insoluble flavonoid compounds were utilized and reacted with arginine to prepare four carbonized polymer dots with good water-solubility in a hydrothermal reactor. Structural characterization demonstrated that the prepared carbonized polymer dots were classic core-shell structure. Effect of the prepared carbonized polymer dots on protein amyloid aggregation was further investigated using hen egg white lysozyme and human lysozyme as model protein in aqueous solution. All of the prepared carbonized polymer dots could retard the amyloid aggregation of hen egg white lysozyme and human lysozyme in a dose-depended manner. All measurements displayed that the inhibition ratio of luteolin-derived carbonized polymer dots (CPDs-1) was higher than that of the other three carbonized polymer dots under the same dosage. This result may be interpreted by the highest content of phenolic hydroxyl groups on the periphery. The inhibition ratio of CPDs-1 on hen egg white lysozyme and human lysozyme reached 88 % and 83 % at the concentration of 0.5 mg/mL, respectively. CPDs-1 also could disaggregate the formed mature amyloid fibrils into short aggregates.


Assuntos
Amiloide , Flavonoides , Muramidase , Polímeros , Agregados Proteicos , Muramidase/química , Muramidase/metabolismo , Humanos , Polímeros/química , Polímeros/farmacologia , Amiloide/química , Amiloide/antagonistas & inibidores , Flavonoides/química , Flavonoides/farmacologia , Agregados Proteicos/efeitos dos fármacos , Animais , Galinhas , Carbono/química
14.
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
15.
PeerJ ; 12: e17237, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38699192

RESUMO

Background: Root perforation repair presents a significant challenge in dentistry due to inherent limitations of existing materials. This study explored the potential of a novel polydopamine-based composite as a root repair material by evaluating its sealing efficacy, radiopacity, and surface topography. Methods: Confocal microscopy assessed sealing ability, comparing the polydopamine-based composite to the gold standard, mineral trioxide aggregate (MTA). Radiopacity was evaluated using the aluminium step wedge technique conforming to ISO standards. Surface roughness analysis utilized atomic force microscopy (AFM), while field emission scanning electron microscopy (FESEM) visualized morphology. Results: The polydopamine-based composite exhibited significantly superior sealing efficacy compared to MTA (P < 0.001). Radiopacity reached 3 mm aluminium equivalent, exceeding minimum clinical requirements. AFM analysis revealed a smooth surface topography, and FESEM confirmed successful composite synthesis. Conclusion: This study demonstrates promising properties of the polydopamine-based composite for root perforation repair, including superior sealing efficacy, clinically relevant radiopacity, and smooth surface topography. Further investigation is warranted to assess its clinical viability and potential translation to endodontic practice.


Assuntos
Compostos de Alumínio , Compostos de Cálcio , Indóis , Óxidos , Polímeros , Materiais Restauradores do Canal Radicular , Silicatos , Propriedades de Superfície , Polímeros/química , Indóis/química , Silicatos/química , Compostos de Cálcio/química , Óxidos/química , Materiais Restauradores do Canal Radicular/química , Compostos de Alumínio/química , Humanos , Combinação de Medicamentos , Microscopia Eletrônica de Varredura , Microscopia de Força Atômica/métodos , Microscopia Confocal , Teste de Materiais , Raiz Dentária/lesões , Raiz Dentária/diagnóstico por imagem , Raiz Dentária/cirurgia
16.
Nat Commun ; 15(1): 3731, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702306

RESUMO

Molecular recognition of proteins is key to their biological functions and processes such as protein-protein interactions (PPIs). The large binding interface involved and an often relatively flat binding surface make the development of selective protein-binding materials extremely challenging. A general method is reported in this work to construct protein-binding polymeric nanoparticles from cross-linked surfactant micelles. Preparation involves first dynamic covalent chemistry that encodes signature surface lysines on a protein template. A double molecular imprinting procedure fixes the binding groups on the nanoparticle for these lysine groups, meanwhile creating a binding interface complementary to the protein in size, shape, and distribution of acidic groups on the surface. These water-soluble nanoparticles possess excellent specificities for target proteins and sufficient affinities to inhibit natural PPIs such as those between cytochrome c (Cytc) and cytochrome c oxidase (CcO). With the ability to enter cells through a combination of energy-dependent and -independent pathways, they intervene apoptosis by inhibiting the PPI between Cytc and the apoptotic protease activating factor-1 (APAF1). Generality of the preparation and the excellent molecular recognition of the materials have the potential to make them powerful tools to probe protein functions in vitro and in cellulo.


Assuntos
Citocromos c , Complexo IV da Cadeia de Transporte de Elétrons , Nanopartículas , Polímeros , Nanopartículas/química , Citocromos c/metabolismo , Citocromos c/química , Humanos , Polímeros/química , Polímeros/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/química , Impressão Molecular/métodos , Ligação Proteica , Apoptose , Micelas , Células HeLa , Animais
17.
Sci Rep ; 14(1): 10293, 2024 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704412

RESUMO

In this study, a sensitive and selective fluorescent chemosensor was developed for the determination of pirimicarb pesticide by adopting the surface molecular imprinting approach. The magnetic molecularly imprinted polymer (MIP) nanocomposite was prepared using pirimicarb as the template molecule, CuFe2O4 nanoparticles, and graphene quantum dots as a fluorophore (MIP-CuFe2O4/GQDs). It was then characterized using X-ray diffraction (XRD) technique, Fourier transforms infrared (FT-IR) spectroscopy, scanning electron microscope (SEM), and transmission electron microscopy (TEM). The response surface methodology (RSM) was also employed to optimize and estimate the effective parameters of pirimicarb adsorption by this polymer. According to the experimental results, the average particle size and imprinting factor (IF) of this polymer are 53.61 nm and 2.48, respectively. Moreover, this polymer has an excellent ability to adsorb pirimicarb with a removal percentage of 99.92 at pH = 7.54, initial pirimicarb concentration = 10.17 mg/L, polymer dosage = 840 mg/L, and contact time = 6.15 min. The detection of pirimicarb was performed by fluorescence spectroscopy at a concentration range of 0-50 mg/L, and a sensitivity of 15.808 a.u/mg and a limit of detection of 1.79 mg/L were obtained. Real samples with RSD less than 2 were measured using this chemosensor. Besides, the proposed chemosensor demonstrated remarkable selectivity by checking some other insecticides with similar and different molecular structures to pirimicarb, such as diazinon, deltamethrin, and chlorpyrifos.


Assuntos
Praguicidas , Pirimidinas , Praguicidas/análise , Carbamatos/análise , Carbamatos/química , Pontos Quânticos/química , Polímeros Molecularmente Impressos/química , Polímeros/química , Espectrometria de Fluorescência/métodos , Grafite/química , Impressão Molecular/métodos , Adsorção , Limite de Detecção , Espectroscopia de Infravermelho com Transformada de Fourier , Nanocompostos/química , Nanocompostos/ultraestrutura
18.
Sci Rep ; 14(1): 10418, 2024 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710793

RESUMO

A new drug delivery system using an asymmetric polyethersulfone (PES) membrane modified by SBA-15 and glutamine-modified SBA-15 (SBA-Q) was prepared in this study by the aim of azithromycin delivery enhancement in both in vitro and ex vivo experiments. The research focused on optimizing membrane performance by adjusting critical parameters including drug concentration, membrane thickness, modifier percentage, polymer percentage, and pore maker percentage. To characterize the fabricated membranes, various techniques were employed, including scanning electron microscopy, water contact angle, and tensile strength assessments. Following optimization, membrane composition of 17% PES, 2% polyvinylpyrrolidone, 1% SBA-15, and 0.5% SBA-Q emerged as the most effective. The optimized membranes demonstrated a substantial increase in drug release (906 mg/L) compared to the unmodified membrane (440 mg/L). The unique membrane structure, with a dense top layer facilitating sustained drug release and a porous sub-layer acting as a drug reservoir, contributed to this improvement. Biocompatibility assessments, antibacterial activity analysis, blood compatibility tests, and post-diffusion tissue integrity evaluations confirmed the promising biocompatibility of the optimized membranes. Moreover, long-term performance evaluations involving ten repeated usages underscored the reusability of the optimized membrane, highlighting its potential for sustained and reliable drug delivery applications.


Assuntos
Antibacterianos , Sistemas de Liberação de Medicamentos , Membranas Artificiais , Polímeros , Dióxido de Silício , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Antibacterianos/química , Dióxido de Silício/química , Polímeros/química , Porosidade , Sulfonas/química , Sulfonas/administração & dosagem , Liberação Controlada de Fármacos , Animais , Azitromicina/administração & dosagem , Azitromicina/farmacocinética , Azitromicina/química , Azitromicina/farmacologia , Humanos
19.
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
20.
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
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