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1.
Food Chem ; 336: 127686, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32763735

RESUMO

The purpose of this study is to investigate the effects of the interfacial layer number on the storage stability and in vitro digestion of fish oil-loaded primary, secondary, tertiary, and quaternary multilayer emulsions stabilized by gelatin particle and polysaccharides (anionic alginate and cationic chitosan), prepared using a layer-by-layer electrostatic deposition technique. The results demonstrate that the emulsion creaming stability during the storage process and the emulsion droplet stability against the gastric phase are dependent on the interfacial layer number. But, the interfacial layer number in the multilayer emulsions has no obvious effects on the droplet stability against droplet coalescence during the storage process and against the small intestinal phases of gastrointestinal tract models. Moreover, it also has no obvious effect on the sustained free fatty acid release of multilayer emulsions. This study can advance the fundamental understanding of multilayer emulsions and promote their potential applications.


Assuntos
Digestão , Óleos de Peixe/química , Armazenamento de Alimentos , Gelatina/química , Polissacarídeos/química , Emulsões , Ácidos Graxos não Esterificados/química , Óleos de Peixe/metabolismo , Tamanho da Partícula , Eletricidade Estática
2.
Food Chem ; 336: 127634, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32777654

RESUMO

Bilayer colorimetric films were developed for monitoring fish spoilage by using gelatin (GN) incorporated with ZnO nanoparticles as the upper layer (GN-ZnO), and gellan gum (GG) incorporated with mulberry anthocyanins (MBA) as the lower layer (GG-MBA). The color stability of the bilayer colorimetric films under visible and ultraviolet light was improved with the increase of ZnO nanoparticles content. Meanwhile, the bilayer films had good NH3 sensitivity. The limit of detection of the GG-MBA/GN-2.0% ZnO film to NH3 was 0.01 mM. The electrochemical writing ability of the bilayer films was also identified, indicating the feasibility of inks-free printing on biopolymer films. Finally, the GG-MBA/GN-2.0% ZnO film with an electrochemical writing pattern was used to monitor crucian spoilage. The GG-MBA/GN-2.0% ZnO film with electrochemical writing pattern showed visible color changes with the crucian spoilage. In conclusion, the bilayer colorimetric film was expected to be a good fish spoilage indicator in smart packaging.


Assuntos
Embalagem de Alimentos/métodos , Inocuidade dos Alimentos , Luz , Animais , Antocianinas/química , Cor , Produtos Pesqueiros/análise , Embalagem de Alimentos/instrumentação , Gelatina/química , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas/química , Morus/química , Morus/metabolismo , Polissacarídeos Bacterianos/química , Resistência à Tração , Óxido de Zinco/química
3.
Food Chem ; 337: 127762, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32777563

RESUMO

Gelatin and collagen are considered halal-critical ingredients as they are typically derived from either bovine or porcine animals. Current analytical methods for determining the sources of gelatin and collagen suffer from limitations in terms of robustness and false positives in peptide matching. Thus, the aim of this study was to investigate the utility of monitoring hydroxyproline, a signature amino acid for gelatin and collagen, for identifying potentially haram foodstuffs. To determine the hydroxyproline profiles among animal- and plant-based samples, one-way univariate analysis of variance followed by pair-wise comparison was used to establish statistical significance. Multivariate chemometric analysis through principal component analysis revealed a discrete distribution pattern among 59 samples due to hydroxyproline variability. Finally, inter- and intra-laboratory comparisons demonstrated the validity and robustness of hydroxyproline determination according to ISO 17025. Thus, this preliminary identification technique will aid the identification of potentially haram foodstuffs.


Assuntos
Colágeno/análise , Análise de Alimentos/métodos , Gelatina/análise , Hidroxiprolina/análise , Animais , Bovinos , Colágeno/química , Gelatina/química , Suínos
4.
Int J Nanomedicine ; 15: 7155-7171, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061373

RESUMO

Objective: Tissue engineering approaches seem to be an attractive therapy for tendon rupture. Novel injectable porous gelatin microcryogels (GMs) can promote cell attachment and proliferation, thus facilitating the repair potential for target tissue regeneration. The research objectives of this study were to assess the efficacy of tissue-like microunits constructed by multiple GMs laden with adipose-derived mesenchymal stem cells (ASCs) in accelerated tendon regeneration in a rat model. Methods: Through a series of experiments, such as isolation and identification of ASCs, scanning electron microscopy, mercury intrusion porosimetry (MIP), laser scanning confocal microscopy and the CCK-8 test, the biocompatibility of GMs was evaluated. In an in vivo study, 64 rat right transected Achilles tendons were randomly divided into four groups: the ASCs+GMs group (microunits aggregated by multiple ASC-laden GMs injected into the gap), the ASCs group (ASCs injected into the gap), the GMs group (GMs injected into the gap) and the blank defect group (non-treated). At 2 and 4 weeks postoperatively, the healing tissue was harvested to evaluate the gross observation and scoring, biomechanical testing, histological staining and quantitative scoring. Gait analysis was performed over time. The 64 rats were randomly assigned into 4 groups: (1) micro-unit group (ASCs+GMs) containing ASC (105)-loaded 120 GMs in 60 µL DMEM; (2) cell control group (ASCs) containing 106 ASCs in 60 µL DMEM; (3) GM control group (GMs) containing 120 blank GMs in 60 µL DMEM; (4) blank defect group (Defect) containing 60 µL DMEM, which were injected into the defect sites. All animals were sacrificed at 2 and 4 weeks postsurgery (Table 1). Results: In an in vitro study, GMs (from 126 µm to 348 µm) showed good porosities and a three-dimensional void structure with a good interpore connectivity of the micropores and exhibited excellent biocompatibility with ASCs. As the culture time elapsed, the extracellular matrix (ECM) secreted by ASCs encased the GMs, bound multiple microspheres together, and then formed active tendon tissue-engineering microunits. In animal experiments, the ASCs+GMs group and the ASCs group showed stimulatory effects on Achilles tendon healing. Moreover, the ASCs+GMs group was the best at improving the macroscopic appearance, histological morphology, Achilles functional index (AFI), and biomechanical properties of repair tissue without causing adverse immune reactions. Conclusion: Porous GMs were conducive to promoting cell proliferation and facilitating ECM secretion. The ASCs-GMs matrices showed an obvious therapeutic efficiency for Achilles tendon rupture in rats.


Assuntos
Tendão do Calcâneo/patologia , Tecido Adiposo/citologia , Criogéis/farmacologia , Células-Tronco Mesenquimais/citologia , Traumatismos dos Tendões/patologia , Traumatismos dos Tendões/terapia , Cicatrização/efeitos dos fármacos , Doença Aguda , Animais , Materiais Biocompatíveis/química , Fenômenos Biomecânicos , Diferenciação Celular , Modelos Animais de Doenças , Fluorescência , Gelatina/química , Masculino , Fenótipo , Porosidade , Ratos Sprague-Dawley , Ruptura , Engenharia Tecidual
5.
Life Sci ; 261: 118381, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32891611

RESUMO

AIM: Development and design of efficient wound dressings are subject of intensive investigations either in basic or in clinical researches. Although, hydrogel-based wound dressings have gained increasing attention and showed beneficial results in term of improved wound healing effect, they are not yet able to heal complex wounds. This study was conducted in an attempt to improve wound healing properties and introduce a novel potential wound dressing. MATERIAL AND METHODS: Wharton's jelly derived-mesenchymal stem cells (WJ-MSCs) were transfected with a recombinant construct encoding hCAP-18/LL-37 gene which has several important functions in wound healing process. Next, the conditioned medium (CM) of the transfected cells (LL-37-MSCs) was harvested, and its concentrate was formulated in a sodium alginate (SA)/gelatin (G) hydrogel. Finally, the wound healing efficacy of the hydrogel-CM combination was evaluated in an excision wound model in rat. KEY FINDINGS: In vitro findings exhibited biocompatibility, biodegradability, acceptable mechanical properties, sustained release, and capacity to absorb wound exudate for the hydrogel. In vivo, the hydrogel effectively accelerated wound contraction and promoted wound healing in comparison to controls. CONCLUSION: Although further investigations including preclinical and clinical studies are required, our findings strongly suggest that the hydrogel might be considered as a potential novel wound dressing for healing of a variety of wounds.


Assuntos
Alginatos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Meios de Cultivo Condicionados/farmacologia , Gelatina/química , Hidrogéis/química , Células-Tronco Mesenquimais/química , Geleia de Wharton/citologia , Cicatrização/efeitos dos fármacos , Animais , Morte Celular/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Masculino , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Suínos , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
Int J Nanomedicine ; 15: 3903-3920, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606657

RESUMO

Background: Researchers are trying to study the mechanism of neural stem cells (NSCs) differentiation to oligodendrocyte-like cells (OLCs) as well as to enhance the selective differentiation of NSCs to oligodendrocytes. However, the limitation in nerve tissue accessibility to isolate the NSCs as well as their differentiation toward oligodendrocytes is still challenging. Purpose: In the present study, a hybrid polycaprolactone (PCL)-gelatin nanofiber scaffold mimicking the native extracellular matrix and axon morphology to direct the differentiation of bone marrow-derived NSCs to OLCs was introduced. Materials and Methods: In order to achieve a sustained release of T3, this factor was encapsulated within chitosan nanoparticles and chitosan-loaded T3 was incorporated within PCL nanofibers. Polyaniline graphene (PAG) nanocomposite was incorporated within gelatin nanofibers to endow the scaffold with conductive properties, which resemble the conductive behavior of axons. Biodegradation, water contact angle measurements, and scanning electron microscopy (SEM) observations as well as conductivity tests were used to evaluate the properties of the prepared scaffold. The concentration of PAG and T3-loaded chitosan NPs in nanofibers were optimized by examining the proliferation of cultured bone marrow-derived mesenchymal stem cells (BMSCs) on the scaffolds. The differentiation of BMSCs-derived NSCs cultured on the fabricated scaffolds into OLCs was analyzed by evaluating the expression of oligodendrocyte markers using immunofluorescence (ICC), RT-PCR and flowcytometric assays. Results: Incorporating 2% PAG proved to have superior cell support and proliferation while guaranteeing electrical conductivity of 10.8 × 10-5 S/cm. Moreover, the scaffold containing 2% of T3-loaded chitosan NPs was considered to be the most biocompatible samples. Result of ICC, RT-PCR and flow cytometry showed high expression of O4, Olig2, platelet-derived growth factor receptor-alpha (PDGFR-α), O1, myelin/oligodendrocyte glycoprotein (MOG) and myelin basic protein (MBP) high expressed but low expression of glial fibrillary acidic protein (GFAP). Conclusion: Considering surface topography, biocompatibility, electrical conductivity and gene expression, the hybrid PCL/gelatin scaffold with the controlled release of T3 may be considered as a promising candidate to be used as an in vitro model to study patient-derived oligodendrocytes by isolating patient's BMSCs in pathological conditions such as diseases or injuries. Moreover, the resulted oligodendrocytes can be used as a desirable source for transplanting in patients.


Assuntos
Materiais Biomiméticos/farmacologia , Células da Medula Óssea/citologia , Diferenciação Celular , Nanofibras/química , Células-Tronco Neurais/citologia , Oligodendroglia/citologia , Tecidos Suporte/química , Compostos de Anilina/química , Animais , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Condutividade Elétrica , Gelatina/química , Grafite/química , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanofibras/ultraestrutura , Células-Tronco Neurais/metabolismo , Oligodendroglia/efeitos dos fármacos , Poliésteres/química , Ratos , Suínos , Tri-Iodotironina/farmacologia
7.
J Biosci Bioeng ; 130(4): 416-423, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32636145

RESUMO

Liquid marbles (LMs) have recently shown a great promise as microbioreactors to construct self-supported aqueous compartments for chemical and biological reactions. However, the evaporation of the inner aqueous liquid core has limited their application, especially in studying cellular functions. Hydrogels are promising scaffolds that provide a spatial environment suitable for three-dimensional cell culture. Here, we describe the fabrication of redox-responsive hydrogel marbles (HMs) as a three-dimensional cell culture platform. The HMs are prepared by introducing an aqueous mixture of a tetra-thiolated polyethylene glycol (PEG) derivative, thiolated gelatin (Gela-SH), horseradish peroxidase, a small phenolic compound, and human hepatocellular carcinoma cells (HepG2) to the inner aqueous phase of LMs. Eventually, HepG2 cells are encapsulated in the HMs then immersed in culture media, where they proliferate and form cellular spheroids. Experimental results show that the Gela-SH concentration strongly influences the physicochemical and microstructure properties of the HMs. After 6 days in culture, the spheroids were recovered from the HMs by degrading the scaffold, and examination showed that they had reached up to about 180 µm in diameter depending on the Gela-SH concentration, compared with 60 µm in conventional HMs without Gela-SH. After long-term culture (over 12 days), the liver-specific functions (secretion of albumin and urea) and DNA contents of the spheroids cultured in the HMs were elevated compared with those cultured in LMs. These results suggest that the developed HMs can be useful in designing a variety of microbioreactors for tissue engineering applications.


Assuntos
Reatores Biológicos , Hidrogéis/química , Esferoides Celulares/metabolismo , Gelatina/química , Células Hep G2 , Peroxidase do Rábano Silvestre/metabolismo , Humanos , Oxirredução , Polietilenoglicóis/química , Engenharia Tecidual
8.
Food Chem ; 333: 127534, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32673948

RESUMO

A new kind of multi-component membrane was prepared by combining gelatin solution, porogen and an inclusion complex of ionic liquid (IL) and beta-cyclodextrin (ß-CD) in a simple physical manner for selective separation of tea polyphenols (TPs) from green tea crude extracts. After screening, it was found that the resulting membrane containing the IL of dicationic N-vinylimidazole proline salt ([VIm]2C3[l-pro]2) had the excellent performance for the enrichment of the target molecules. Then the newly-developed film was comprehensively characterized by scanning electron microscopy, conductivity, thermogravimetry and spectral analysis. Under pressure driving, the adsorption from an aqueous solution of a mixture of TPs and theophylline on IL@ß-CD-Gel membrane showed that the adsorption capacity for TPs was 303.45 mg/g with removal percentages of 94.38%. The experimental data fit well with pseudo-second-order model and Freundlich model. By using this composite material, a new technology of membrane separation for selective adsorption of TPs was finally established.


Assuntos
Fracionamento Químico/métodos , Gelatina/química , Líquidos Iônicos/química , Membranas Artificiais , Polifenóis/isolamento & purificação , Chá/química , beta-Ciclodextrinas/química , Polifenóis/análise
9.
Int J Nanomedicine ; 15: 4625-4637, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32636622

RESUMO

Purpose: Besides the tumor cells themselves, solid tumors are comprised of numerous cell types including infiltrating immune cells such as tumor-associated macrophages (TAMs). TAMs are vital stromal components of host immune system and play a critical role in the development of cancer. TAMs can be divided into two subtypes: M1 tumor-suppressive macrophage and M2 tumor-supportive macrophage. To better address the observations of TAMs functional performance, we describe an in vitro system that mimics the populations of TAMs infiltrated into the tumor mass by using our disintegrable supramolecular gelatin (DSG) hydrogels, which are physically crosslinked by host-guest complexations. Materials and Methods: The host-guest interaction was adopted between the aromatic groups of gelatin and the photocrosslinkable acrylated ß-cyclodextrins (Ac-ß-CDs) to form the DSG hydrogels. The convenient macrophage/endometrial cancer cells heterospheroid 3D model was set up by DSG hydrogels. RT-PCR and Western blot assays were developed to evaluate the efficiencies of inducers on the macrophages. The ELISA and oxygen saturation assays were performed to measure the secretion of VEGF and consumption of oxygen of tumor and/or macrophages, respectively. To determine the antitumor effects of M2 reprogrammed macrophages in vitro and in vivo, migration assay and tumor xenograft model were used, respectively. Results: The host-guest complexations of DSG hydrogels were controllably broken efficiently by soaking into the solution of competitive guest monomers 1-adamantanamine hydrochloride. The DSG hydrogels help IFN-γ reprogram the M2 to M1 and then decrease the tumor/M2 reprogrammed macrophage cells heterospheroid secretion of VEGF and increase the relative oxygen saturation. Significantly, the co-cultural tumor/M2 reprogrammed group from the disintegrated DSG hydrogels reduced the migration of cancer cells in vitro and the tumor growth in vivo. Conclusion: We obtain a TAMs/tumor microenvironment-responsive 3D model based on the novel DSG hydrogels, and will be of utility in cancer therapy and drug discovery.


Assuntos
Neoplasias do Endométrio/patologia , Gelatina/química , Hidrogéis/química , Macrófagos/citologia , Macrófagos/transplante , Animais , Técnicas de Cultura de Células , Neoplasias do Endométrio/terapia , Matriz Extracelular/patologia , Feminino , Gelatina/farmacocinética , Humanos , Hidrogéis/farmacocinética , Camundongos Endogâmicos BALB C , Esferoides Celulares/citologia , Microambiente Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
10.
J Food Sci ; 85(7): 1988-1996, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32602184

RESUMO

The effects of adding bovine skin gelatin hydrolysate obtained with subtilisin, on water-holding capacity (WHC), in a thermally processed chicken meat model, were investigated. Hydrolysates with different degrees of hydrolysis (DH) (6.57%, 13.14%, and 26.28%) were prepared. The results showed that all the tested hydrolysates improved water retention in the meat matrix. The hydrolysate with 26.28% DH showed similar behavior throughout the full range of concentrations [0% to 5% w/w] compared to that of the positive control (sodium tripolyphosphate [STPP]). In addition, the other hydrolysates [6.57% DH and 13.14% DH at 3% and 2.5% w/w concentrations, respectively] showed behaviors that coincided with that of STPP at its maximum limit allowed. A correlation was observed between the WHC and the pH of the meat samples treated with each hydrolysate or STPP. In addition, it was found that the WHC of the hydrolysates was due to increases in pH and the specific effects of the hydrolysate beyond the typical effects of pH and ionic strength in meat systems. The solubility of all hydrolysates was high (>90%). In conclusion, bovine skin gelatin hydrolysates could serve as an alternative to polyphosphates to improve water retention and the functional properties of thermally processed meat products. PRACTICAL APPLICATION: This study investigated the effects of adding bovine skin gelatin hydrolysate obtained with subtilisin on water-holding capacity (WHC) in a thermally processed chicken meat model. It was found that the hydrolysis of bovine skin gelatin with subtilisin can replace chemical products harmful to health, such as STPP, in terms of water-holding capacity. Therefore, bovine skin gelatin hydrolysate can be used as an ingredient in the formulation of thermally processed meat products.


Assuntos
Gelatina/química , Polifosfatos/química , Pele/química , Animais , Bovinos , Temperatura Alta , Concentração de Íons de Hidrogênio , Hidrólise , Hidrolisados de Proteína/química , Solubilidade , Água/química
11.
J Food Sci ; 85(7): 2124-2133, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32579742

RESUMO

Microencapsulation by production of polymer beads from ionic gelation is a useful method to improve the stability of nutritional compounds. Wheat germ oil is a nutritional source of unsaturated fatty acids and phytonutrients, such as tocopherols (α and ß), phytosterols, carotenoids, and phenolic compounds. This work studied the development of alginate-starch beads over the stability of encapsulated wheat germ oil. The beads contained sodium alginate and gelatinized corn starch in proportions of 2:0, 1:1, 1:2, and 1:4. The addition of small amounts (1:1) of gelatinized starch in the alginate emulsions improved the physicochemical properties and stability during storage. The emulsions had oil droplets with mean sizes ranging from 4.5 to 12.2 µm. The 1:1 samples showed more disperse oil droplets, explained by the molecular interaction between the starch chains and oil. The encapsulation efficiency was higher than 91%, and the beads' mean diameters were between 383.22 and 797.45 µm. The proportion of 1:1 alginate-starch also enhanced the beads' microstructures, avoiding oil oxidation. Six days accelerated stability (65 °C) evidenced higher tocopherols amounts (0.66 mg/g oil) and a lower oxidation (2.52 meq.O2 /kg oil) for the 1:1 samples compared to the remained samples. PRACTICAL APPLICATION: Alginate-gelatinized corn starch beads loaded with wheat germ oil can be used as an ingredient in functional food products for the enrichment of nutrients. The use of starch decreased the oil oxidation and the loss of tocopherols during storage, indicating that the quality of the wheat germ oil will be desirable for longer durations of food storage.


Assuntos
Composição de Medicamentos/métodos , Óleos Vegetais/química , Amido/química , Tocoferóis/química , Zea mays/química , Alginatos/química , Estabilidade de Medicamentos , Emulsões/química , Gelatina/química , Oxirredução
12.
J Food Sci ; 85(7): 2060-2068, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32579746

RESUMO

The aim of this study was the development of innovative candies formulations accordant with the present trends in the confectionery industry. Steviol glycosides, sorbitol, and agave syrup were used as sucrose alternatives, while agar and pectin were included instead of gelatin for the formulation of vegan candies. Additionally, white tea extract was used as a candy base and source of bioactive compounds. Bioactive quality (total phenolic content, antioxidant capacity, epigallocatechin gallate, and caffeine content) and physicochemical (dry matter, springiness, hardness, color) parameters of candies were monitored during 4 months of storage at 4 and 22 °C. Pectin candies with the highest content of dry matter (79.8%) showed the longest shelf life, while those with agar (52.0% and 66.2%) were the most susceptible to spoilage. Candies prepared with agar were less hard (0.4 and 0.6 N) and with less elastic texture (1.5 and 3.4 mm) and showed the highest stability of physicochemical parameters during storage, while those with pectin were also less hard (0.5 N) but with more elastic texture (10.7 mm) than gelatin candies (3.6 and 4.4 mm; 2.4 and 4.1 N). Although gelatin samples were characterized with the greatest bioactive quality parameters immediately after production, they showed a higher instability of the same parameters during storage compared to the agar and pectin candies. PRACTICAL APPLICATION: According to the consumers' demands for healthier confectionery products, formulations of candies with sucrose alternatives, non-animal hydrocolloids, and natural bioactive compounds were developed. Giving a deeper insight into their physicochemical and bioactive properties, this paper could contribute to confectionery industry in development and optimization of formulations in order to obtain candies with desirable and attractive properties.


Assuntos
Camellia sinensis/química , Doces/análise , Aditivos Alimentares/análise , Manipulação de Alimentos/métodos , Extratos Vegetais/análise , Antioxidantes/análise , Catequina/análogos & derivados , Catequina/análise , Armazenamento de Alimentos , Gelatina/química
13.
PLoS One ; 15(5): e0232851, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32392238

RESUMO

Here we present the synthesis and characterization of two new conducting materials having a high electro-chemo-mechanical activity for possible applications as artificial muscles or soft smart actuators in biomimetic structures. Glucose-gelatin nanofiber scaffolds (CFS) were coated with polypyrrole (PPy) first by chemical polymerization followed by electrochemical polymerization doped with dodecylbenzensulfonate (DBS-) forming CFS-PPy/DBS films, or with trifluoromethanesulfonate (CF3SO3-, TF) giving CFS-PPy/TF films. The composition, electronic and ionic conductivity of the materials were determined using different techniques. The electro-chemo-mechanical characterization of the films was carried out by cyclic voltammetry and square wave potential steps in bis(trifluoromethane)sulfonimide lithium solutions of propylene carbonate (LiTFSI-PC). Linear actuation of the CFS-PPy/DBS material exhibited 20% of strain variation with a stress of 0.14 MPa, rather similar to skeletal muscles. After 1000 cycles, the creeping effect was as low as 0,2% having a good long-term stability showing a strain variation per cycle of -1.8% (after 1000 cycles). Those material properties are excellent for future technological applications as artificial muscles, batteries, smart membranes, and so on.


Assuntos
Órgãos Artificiais , Materiais Biomiméticos , Materiais Revestidos Biocompatíveis/química , Nanofibras , Polímeros/química , Pirróis/química , Tecidos Suporte , Benzenossulfonatos/química , Condutividade Elétrica , Eletroquímica , Gelatina/química , Glucose/química , Mesilatos/química , Microscopia Eletrônica de Varredura , Músculos , Nanofibras/química , Nanofibras/ultraestrutura , Polimerização , Potenciometria , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Propriedades de Superfície , Tecidos Suporte/química
14.
Food Chem ; 328: 127114, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32473491

RESUMO

The application of fish gelatins in emulsions has attracted much attention and their stabilization mechanisms remain unclear. This work explores the effect of extraction methods on the structural characteristics, functional properties, and emulsion application of Tilapia skin gelatins. The creaming stability of Tilapia skin gelatin-stabilized emulsions are dependent on gelatin secondary structure, gelatin fat-binding capacity, the presence of NaCl, and storage temperatures. The emulsion creaming velocities are: acetic acid-extracted gelatin (AAG) ≈ hot water-extracted gelatin (HWG) > pepsin enzyme-extracted gelatin (PEG). The emulsion creaming velocities in the presence of NaCl are: AAG < HWG ≈ PEG. The stability mechanisms are involved with a "protein secondary structure - molecular interaction - emulsion droplet structure - emulsion stability" route. This work provides useful information for understanding the relationships between the structural characteristics and emulsion stability of gelatins. The fish oil-loaded Tilapia skin gelatin-stabilized emulsions also show promising prospective applications in food beverages.


Assuntos
Gelatina/química , Tilápia , Animais , Emulsões/química , Óleos de Peixe/química , Pele/química , Temperatura
15.
AAPS PharmSciTech ; 21(5): 148, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32436061

RESUMO

The aim of this study was to evaluate the potential of a cross-linked pregelatinized potato starch (PREGEFLO® PI10) as matrix former for controlled release tablets. Different types of tablets loaded with diprophylline, diltiazem HCl or theophylline were prepared by direct compression of binary drug/polymer blends. The drug content was varied from 20 to 50%. Two hydroxypropyl methylcellulose grades (HPMC K100LV and K100M) were studied as alternative matrix formers. Drug release was measured in a variety of release media using different types of experimental set-ups. This includes 0.1 N HCl, phosphate buffer pH 6.8 and water, optionally containing different amounts of NaCl, sucrose, ethanol or pancreatin, fasted state simulated gastric fluid, fed state simulated gastric fluid, fasted state simulated intestinal fluid, fed state simulated intestinal fluid as well as media simulating the conditions in the colon of healthy subjects and patients suffering from Crohn's disease. The USP apparatuses I/II/III were used under a range of operating conditions and optionally coupled with the simulation of additional mechanical stress. Importantly, the drug release kinetics was not substantially affected by the investigated environmental conditions from tablets based on the cross-linked pregelatinized potato starch, similar to HPMC tablets. However, in contrast to the latter, the starch-based tablets roughly kept their shape upon exposure to the release media (they "only" increased in size) during the observation period, and the water penetration into the systems was much less pronounced. Thus, the investigated cross-linked pregelatinized potato starch offers an interesting potential as matrix former in controlled release tablets.


Assuntos
Preparações de Ação Retardada/química , Solanum tuberosum/química , Amido/química , Diltiazem/química , Liberação Controlada de Fármacos , Gelatina/química , Humanos , Derivados da Hipromelose/química , Comprimidos/química , Teofilina/química
16.
J Vis Exp ; (159)2020 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-32421007

RESUMO

During the extrusion-based three-dimensional bioprinting process, liquid-like bioinks with low viscosity can protect cells from membrane damage induced by shear stress and improve the survival of the encapsulated cells. However, rapid gravity-driven cell sedimentation in the reservoir could lead to an inhomogeneous cell distribution in bioprinted structures and therefore hinder the application of liquid-like bioinks. Here, we developed a novel multilayered modified strategy for liquid-like bioinks (e.g., gelatin methacryloyl with low viscosity) to prevent the sedimentation of encapsulated cells. Multiple liquid interfaces were manipulated in the multilayered bioink to provide interfacial retention. Consequently, the cell sedimentation action going across adjacent layers in the multilayered system was retarded in the bioink reservoir. It was found that the interfacial retention was much higher than the sedimental pull of cells, demonstrating a critical role of the interfacial retention in preventing cell sedimentation and promoting a more homogeneous dispersion of cells in the multilayered bioink.


Assuntos
Materiais Biocompatíveis/química , Bioimpressão , Células/metabolismo , Hidrogéis/química , Tinta , Impressão Tridimensional , Animais , Sobrevivência Celular , Fibroínas/química , Gelatina/química , Metacrilatos/química , Camundongos , Células NIH 3T3 , Viscosidade
17.
AAPS PharmSciTech ; 21(4): 127, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32390062

RESUMO

The aim of the present study was to evaluate the development of an intra-articular nonsteroidal anti-inflammatory drug gelatin microsphere formulation based on quality risk management and quality by design approaches. Specifically, after setting the quality target product profile and the critical quality attributes, risk assessment was performed by constructing Ishikawa fishbone diagrams based on preliminary hazard analysis. A Plackett-Burman screening experimental design was applied in order to identify the factors (previously classified by risk assessment analysis as having high risk of failure) having a statistically significant impact on the formation of gelatin microspheres. Particle size, polydispersity index, and drug loading were used as responses, while diclofenac sodium was selected as a model drug. All drug-loaded gelatin microspheres were prepared by emulsion-crosslinking process. Screening results showed that gelatin type, surfactant type and quantity, oil phase type, emulsification speed, and glutaraldehyde's concentration had a statistically significant impact on microsphere's final and intermediate critical quality attributes. A design space was then constructed based on central composite design overlaying contour plots, while verification experiments for the optimum suggested formulation (derived from a set control strategy) showed good agreement between the predicted and the experimentally observed results. In addition, the physicochemical characterization of the optimum formulation showed the formation of significant molecular interactions between the drug and the gelatin matrix, leading to the complete amorphization of diclofenac within the microsphere structure, while dissolution release experiments showed a biphasic release profile which extended the drug's release for up to 30 days, governed by a Fickian diffusion release mechanism.


Assuntos
Anti-Inflamatórios não Esteroides/química , Diclofenaco/química , Desenvolvimento de Medicamentos/normas , Gelatina/química , Microesferas , Pesquisa Qualitativa , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/metabolismo , Bovinos , Diclofenaco/administração & dosagem , Diclofenaco/metabolismo , Desenvolvimento de Medicamentos/métodos , Liberação Controlada de Fármacos , Gelatina/administração & dosagem , Gelatina/metabolismo , Injeções Intra-Articulares , Tamanho da Partícula , Gestão de Riscos , Suínos
18.
AAPS PharmSciTech ; 21(4): 128, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32399597

RESUMO

Capsule-based dry powder inhaler (DPI) products can be influenced by a multitude of interacting factors, including electrostatic charging. Tribo-charging is a process of charge transfer impacted by various factors, i.e., material surface characteristics, mechanical properties, processing parameters and environmental conditions. Consequently, this work aimed to assess how the charging behavior of capsules intended for inhalation might be influenced by environmental conditions. Capsules having different chemical compositions (gelatin and hydroxypropyl methylcellulose (HPMC)) and distinct inherent characteristics from manufacturing (thermally and cold-gelled) were exposed to various environmental conditions (11%, 22% and 51% RH). Their resulting properties were characterized and tribo-charging behavior was measured against stainless steel and PVC. It was observed that all capsule materials tended to charge to a higher extent when in contact with PVC. The tribo-charging of the thermally gelled HPMC capsules (Vcaps® Plus) was more similar to the gelatin capsules (Quali-G™-I) than to their HPMC cold-gelled counterparts (Quali-V®-I). The sorption of water by the capsules at different relative humidities notably impacted their properties and tribo-charging behavior. Different interactions between the tested materials and water molecules were identified and are proposed to be the driver of distinct charging behaviors. Finally, we showed that depending on the capsule types, distinct environmental conditions are necessary to mitigate charging and assure optimal behavior of the capsules.


Assuntos
Fenômenos Químicos , Inaladores de Pó Seco/métodos , Derivados da Hipromelose/química , Eletricidade Estática , Administração por Inalação , Cápsulas , Avaliação Pré-Clínica de Medicamentos/métodos , Excipientes/química , Excipientes/metabolismo , Gelatina/química , Gelatina/metabolismo , Derivados da Hipromelose/metabolismo , Pós
19.
Zhongguo Zhong Yao Za Zhi ; 45(5): 1188-1193, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32237464

RESUMO

Cervi Colla, deer's gelatin, had two kinds of original sources historically, including the skin and antler of deer, known as Cervi Corii Colla(Lupijiao, LPJ) and Cervi Cornus Colla(Lujiaojiao, LJJ) respectively.LJJ is the mainstream of the market, while LPJ is only used by common people in Guizhou and Jilin etc. This article sorted out the ancient and modern literature(since Rites of the Zhou in Zhou Dynasty) on Cervi Colla and conducted the herbalogical study. The results of the study include:① In ancient China, there were six types of commonly-used Colla derived from six animals, including deer, horse, cow, rat, fish and rhinoceros. Cervi Colla was ranked the most top among them, and it was often used as adhesive to make bow and Chinese inksticks and more commonly used as a medicine.Cervi Cornus Colla was first described as a medicinal by the name "Bai Jiao"(white gelatin)in The Divine Husbandman's Classic of Material Medica(Shen Nong Ben Cao Jing).② Initially, both the skin and antler were used as raw materials to make Cervi Colla, but antler became the only raw material, and deer skin disappeared from the mainstream of raw materials for Cervi Colla. This can be attributed to other diverse and luxurious uses of the skin, such as making dress and hats, etc., and the easy accessibility of deer antlers. ③ The sources of Cervi Colla were not limited to Cervus elaphus(red deer) or C. nippon(sika deer), and it also included animal from the family Cervidae, such as Elaphurus davidianus(elk) and C. unicolor(sambar). ④ The processing method was passed down from ancient times to the present, and no significant changes had occurred. ⑤ LPJ and LJJ had many similar effects, and their nature was both warm. The effect of LJJ was to warm the liver and kidney, replenish vital essence and blood, and to reinforce Yang. While the effect of LPJ was to reinforce both Yin and Yang, replenish blood, and stop bleeding. It has a unique advantage for both reinforcing Yin and Yang. The findings of this paper can provide support for the promotion of LPJ and the development of its medicinal value.


Assuntos
Chifres de Veado/química , Cervos , Gelatina/química , Materia Medica/química , Pele/química , Animais , China
20.
Artigo em Inglês | MEDLINE | ID: mdl-32334390

RESUMO

This study established a validated analytical method for the first time on the determination of nitrofuran metabolites, including semicarbazide (SEM), 1-aminohydantoin (AHD), 3-amino-2-oxazolidinone (AOZ) and 3-amino-5-morpholinomethyl-2-oxazolinone (AMOZ) in gelatin Chinese medicine. A C18 column with the mobile phase consisting of acetonitrile and 5 mmol/L ammonium acetate in water was used to separate these nitrofuran metabolites. The limit of detection of SEM, AHD, AOZ and AMOZ were found to be 0.2 µg/kg, 0.3 µg/kg, 0.2 µg/kg and 0.2 µg/kg, whereas their limit of quantification were 0.6 µg/kg, 0.8 µg/kg, 0.6 µg/kg and 0.5 µg/kg. These nitrofuran metabolites exhibited a good linear standard curve (regression coefficients above 0.99) with a concentration range of 2 µg/L to 100 µg/L. Regarding extraction procedure, gelatin Chinese medicine was pre-treated with pepsin and then extracted using 5% formic acid (v/v) in acetonitrile. The resultant extract was purified through dispersive solid phase extraction using 1000 mg anhydrous sodium sulfate, 300 mg octadecyl carbon silica gel sorbent absorbent and 500 mg ethylenediamine-N-propyl carbon silica gel absorbent, and then further purified on Oasis PRiME HLB cartridges. The matrix effect was effectively eliminated after the clean-up procedure as confirmed by comparing the ratio of standard curves prepared by standards dissolved in both matrix solvent and 5 mmol/L ammonium acetate in water: acetonitrile (95:5, v/v). The recoveries of these nitrofuran metabolites under the 1 µg/kg, 2 µg/kg and 10 µg/kg spiking levels were between 77.4% and 95.6%. These metabolites after the extraction were stable at 4 °C for 24 h. The validated method was used to analyze the residue level of these nitrofuran metabolites in 25 gelatin Chinese medicines. Results showed that only one Colla Corii Asini sample contained SEM (2.52 µg/kg) and AOZ (6.27 µg/kg), whereas one Testudinis Carapacis et Plastri sample had SEM (1.27 µg/kg) and AMOZ (9.53 µg/kg).


Assuntos
Medicamentos de Ervas Chinesas/química , Gelatina/química , Nitrofuranos/análise , Nitrofuranos/metabolismo , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Exoesqueleto/química , Animais , Cromatografia Líquida de Alta Pressão , Hidantoínas/análise , Hidantoínas/metabolismo , Limite de Detecção , Oxazolidinonas/análise , Oxazolidinonas/metabolismo , Reprodutibilidade dos Testes , Semicarbazidas/análise , Semicarbazidas/metabolismo , Temperatura , Fatores de Tempo , Tartarugas
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