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1.
Chem Commun (Camb) ; 56(8): 1255-1258, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31898700

RESUMO

Here we demonstrated that the stiffness of cationized gelatin nanoparticles determined the efficiency of RNAi in myeloid leukemia cells when the particle size and surface charges were kept constant. The siRNA delivery system with an elastic modulus of 0.87 MPa showed the largest siRNA uptake and RNAi efficiency for hard-to-transfect suspension cells.


Assuntos
Gelatina/química , Leucemia Mieloide/patologia , Nanopartículas/química , Interferência de RNA , Cátions/química , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Humanos , Células K562 , Leucemia Mieloide/tratamento farmacológico , Tamanho da Partícula , RNA Interferente Pequeno/química , RNA Interferente Pequeno/farmacologia , Propriedades de Superfície
2.
Food Chem ; 313: 126078, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31945699

RESUMO

Effects of Chlorogenic acid-Gelatin (CGA-Gel) combined with partial freezing on quality change of sword prawn (Parapenaeopsis hardwickii) stored at -5 °C were evaluated for 23 days. Changes in sensory score, total viable counts (TVC), and physiochemical indexes including pH, total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS) and Ca2+-ATPase were examined. All shrimp treated with CGA and CGA-Gel had lower total viable counts compared to control (P < 0.05). The value of TVB-N and TBA of CGA-Gel treated group at day 13 were 18.4 mg N/100 g and 0.175 mg/100 g respectively, both below the proposed safe limits and values of CGA treated group. All the results demonstrated that Chlorogenic acid can inhibit growth of microorganism, lipid oxidation and protein degradation. CGA-Gel treated samples presented better quality preservation effects than CGA treated alone. Therefore, CGA-Gel combined with partial freezing is promising in sword prawn shelf life extension.


Assuntos
Ácido Clorogênico/química , Conservação de Alimentos/métodos , Gelatina/química , Penaeidae/fisiologia , Animais , ATPases Transportadoras de Cálcio/metabolismo , Ácido Clorogênico/farmacologia , Congelamento , Humanos , Concentração de Íons de Hidrogênio , Peroxidação de Lipídeos/efeitos dos fármacos , Proteólise/efeitos dos fármacos
3.
Adv Exp Med Biol ; 1232: 369-374, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893433

RESUMO

Multispectral/hyperspectral imaging is one of the imaging modalities to visualize and quantify blood supply in surface tissues such as skin or mucosa. The results of visualization can be potentially affected by various factors, for instance by elevated methemoglobin (MetHb) content (e.g., methemoglobinemia). The scope of the current study is to develop a robust approach for fabrication and validation of tissue-mimicking phantoms, which can be used to assess and improve tissue oximetry. METHODS: The realistic tissue mimicking gelatin-based phantoms with intralipid (4% v/v) and/or hemoglobins (oxy-, deoxyhemoglobins, and MetHb) were molded between two coverslips separated by 2-mm wires. The hemoglobin solutions were prepared by dissolving the lyophilized human hemoglobin powder (H7379, Sigma-Aldrich) in the deionized water. Sodium dithionite (85% purity, 157,953, Sigma-Aldrich) was used to reduce MetHb solution. The phantoms were imaged using a multispectral imaging device (Oxilight, Canada).To demonstrate the utility, the developed approach is applied to emulate elevated systemic MetHb content. RESULTS: Initial results show that elevated systemic MetHb (2.0-6.7% of total blood) does not impact the accuracy of tissue oximetry imaging. DISCUSSION: A robust method for fabrication and optical validation of biocompatible tissue-mimicking phantoms has been developed.The proposed phantom design allows combining different phantoms into multilayer (sandwich) structures, which can be used to emulate a wide range of topical and systemic conditions.


Assuntos
Gelatina , Oximetria , Imagens de Fantasmas , Canadá , Gelatina/química , Humanos , Metemoglobina/análise , Metemoglobinemia/diagnóstico , Oximetria/métodos , Oximetria/normas , Imagens de Fantasmas/normas
4.
Food Chem ; 310: 125817, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31734010

RESUMO

This study investigated the effects of natural high temperature in the field during grain filling stage on the morphological structure and physicochemical properties of rice starch. High natural field temperature during rice grain filling stage resulted in poor processing and appearance quality, higher gelatinization properties including gelatinization temperature, gelatinization enthalpy, swelling power, and water solubility due to the reduction of amylose content. High temperature decreased the setback and trough viscosities, and increased breakdown, implying that the pasting properties were slightly better. High temperature did not change the starch crystalline type, while it significantly affected relative crystallinity, as well as pitting and unevenness on the surface of the starch granules with lower granule size. The above results imply that high temperature can degrade cooking and eating quality, and increase pasting properties of starch slightly.


Assuntos
Oryza/química , Oryza/fisiologia , Amido/química , Amilose/análise , Culinária , Gelatina/química , Temperatura Alta , Oryza/crescimento & desenvolvimento , Sementes/química , Sementes/crescimento & desenvolvimento , Solubilidade , Temperatura Ambiente , Viscosidade
5.
Carbohydr Polym ; 227: 115348, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31590881

RESUMO

Ecofriendly chitosan-gelatin (Ch-ge) bio-composite films containing Quercetin-starch (Q) were synthesized using solution casting method. Physicochemical characteristics and mechanical properties of the resulting chitosan-gelatin containing Quercetin-starch films (Ch-ge-Q) were studied using UV, FTIR, XRD and SEM techniques. The films were also investigated for their swelling, water-vapor permeability (WVP), water solubility properties. The FTIR spectra confirmed the chemical interactions between the chitosan-gelatin and Q. Surface morphology of prepared film was analyzed by the SEM imaging while XRD spectra suggest the expanded crystallinity of the film with the addition of Q. The film also showed enhanced barrier property against UV rays. The reduction of water-vapor permeability and increase in tensile strength while a decrease in elongation at break has been observed in the Ch-ge-Q film compared to Ch-ge film. The antibacterial activity of Ch-ge-Q film against both gram positive (B. substilis) and gram negative (E. coli) bacteria suggested the Q loaded Ch-ge films as more feasible antibacterial candidate especially against the strain E. coli. The antioxidant activity of the Ch-ge-Q film was evaluated using the DPPH and ABTS as standards and corresponded to 81.45% of DPPH and 72.2% of ABTS scavenging activities. It was observed that the film containing Quercetin-starch presented superior antioxidant activity results in comparison to Ch-ge film promising its application in food packaging.


Assuntos
Antibacterianos/química , Antioxidantes/química , Quitosana/química , Embalagem de Alimentos , Gelatina/química , Quercetina/química , Bacillus subtilis/crescimento & desenvolvimento , Benzotiazóis/química , Compostos de Bifenilo/química , Escherichia coli/crescimento & desenvolvimento , Oxigênio/química , Permeabilidade , Picratos/química , Ácidos Sulfônicos/química , Raios Ultravioleta , Água/química
6.
Food Chem ; 309: 125642, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31685367

RESUMO

As the differences of traditional and Pickering emulsions might have resulted from stabilizer structures, this study analyzes the effects of gelatin molecular structures (uncrosslinked molecules vs. crosslinked molecules) on the preparation, long-term storage, and dilution of fish oil-loaded traditional and Pickering emulsions. Both traditional and Pickering emulsions have three types of droplets with different sizes, and all the droplet sizes were exponentially decreased with the increase of stabilizer concentration. Pickering emulsions have slightly lower droplet sizes compared with traditional emulsions. Traditional emulsions have three different emulsion forms (liquid, redispersible emulsion gel, and unredispersible emulsion gel), whereas Pickering emulsions only have the liquid form. Emulsion creaming stability was dependent on stabilizer molecular structures and stabilizer concentrations. The two emulsions have similar and good dilution stability. This work demonstrates that gelatin molecular structures affect droplet size, emulsion forms, and creaming stability, but not droplet size types and emulsion dilution stability.


Assuntos
Emulsões/química , Óleos de Peixe/química , Gelatina/química , Armazenamento de Alimentos , Microscopia de Força Atômica , Nanopartículas/química , Água/química
7.
Food Chem ; 308: 125675, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31654978

RESUMO

The effects of starch origin on water migration and starch transformation were investigated using one- and two-dimensional Time-domain NMR (TD-NMR) methods. The quantification of T1 and especially of T2 relaxation times during thermal treatment enabled their interpretation relative to the sorption, gelatinization and retrogradation phenomena of starches in the presence of water, in a level close to that used for bread making (50%, wet basis). Comparison between native wheat, waxy corn and potato starches made possible to link relaxation variations to starch structure and properties as crystallinity, granule size, polymorphism, amylopectin content and water-binding capacity all along heating, cooling and storage processes.


Assuntos
Solanum tuberosum/química , Amido/química , Triticum/química , Zea mays/química , Gelatina/química , Imagem por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Água/química
8.
Food Chem ; 308: 125597, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31648095

RESUMO

The simultaneous application of proteins and surfactants for emulsion preparation and stabilization is a research hotspot in the field of emulsions, and their interfacial adsorption mechanisms remain unclear. In order to analyze the interaction mechanism of gelatin with low-molecular-weight surfactants, we mainly explored the preparation and storage of fish oil-loaded gelatin/surfactant-stabilized emulsions in this work. The results demonstrated that gelatin and four types of surfactants were synergetically (Span 80 and soybean lecithin) or competitively (Tween 80 and SDS) adsorbed on the oil/water interfaces in the emulsions. The adsorption behaviors affected emulsion stability (creaming, liquid-gel transformation, and droplet coalescence behaviors) and size distribution of emulsion droplets. These fish oil-loaded gelatin/surfactant-stabilized emulsions have the potential to reduce the disadvantages of fish oils and to provide multiple prospective applications in beverages, hard foods, and alkaline foods. It would also be beneficial to the basic understanding of protein/surfactant interfacial adsorption in emulsion formation.


Assuntos
Óleos de Peixe/química , Gelatina/química , Tensoativos/química , Adsorção , Emulsões , Peso Molecular , Estudos Prospectivos , Água/química
9.
Food Chem ; 308: 125599, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31648098

RESUMO

In this work, sequential electrospinning was utilized to fabricate a multilayer film with ethylcellulose nanofibers as the outer layer and curcumin-loaded gelatin nanofibers as the inner layer. Field-emission scanning electronic microscopy observations showed that the outer and inner layers had a smooth surface and clear boundary. The hydrophobic outer layers decreased the water vapor permeability and improved the water contact resistance of the hydrophilic inner layer, and the intimate interactions of hydrogen bonds between two adjacent layers enhanced the thermal stability. The multilayer film exhibited a sustained release manner of the encapsulated curcumin for 96 h, compared to the burst release within 30 min from the gelatin film. In addition, the antioxidant activities of the released curcumin from the multilayer film were well retained within 96 h. These results suggested that the multilayer nanofibrous film fabricated by sequential electrospinning has potential applications in bioactive encapsulation and controlled release.


Assuntos
Celulose/análogos & derivados , Curcumina/química , Gelatina/química , Nanofibras/química , Celulose/química , Preparações de Ação Retardada/química , Ligações de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Água/química
10.
Food Chem ; 308: 125577, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31669942

RESUMO

Leveraging phenolic complexation to optimize starch functionality and digestibility is restrained by the obscurity of their physicochemical nature and molecular basis. To define starch-phenolic complexes under hydrothermal treatments, maize amylopectin and potato starch were complexed with caffeic acid, ferulic acid and gallic acid. Starch hydrothermal stability and digestibility were measured by differential scanning calorimeter and Englyst's method, respectively. While monosaccharide compositions and glycosidic linkages were analyzed by GC-MS, hydrodynamic radius and proton magnetic resonance of gelatinized complexes were measured by dynamic light scattering and NMR respectively. Compared with native starches, starch-phenolic complexes were not chemically modified and had modestly lower estimated glycemic indexes and significantly lower gelatinization temperatures (p < 0.05). Starch-phenolic complexes also had significantly lower levels of phenolic proton intensities and hydrodynamic radii relative to the control starch-phenolic mixtures (p < 0.05). These results suggested that phenolics may complex with starch through non-covalent CH-π bonds along α-(1 → 4) glycosidic chains.


Assuntos
Amido/química , Zea mays/química , Varredura Diferencial de Calorimetria , Gelatina/química , Hidrodinâmica , Fenóis/química
11.
Food Chem ; 305: 125454, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505413

RESUMO

The effects of the (-)-Epigallocatechin gallate (EGCG)-gelatin biofilm treatment (EGT) on microbial composition and quality of tilapia fillets stored at low temperatures were evaluated. The changes in mechanical properties, microbial reproduction, as well as lipid and protein oxidation during fillets storage were determined. The results showed that EGT reduced the microbial count and the relative abundance of the fillets. And EGT delayed the rate of lipid oxidation and protein denaturation in fillets. Compared with the control group, EGT samples had lower K values (74% on 18 d) and biogenic amines (39 mg/kg for putrescine and 50 mg/kg for cadaverine on 21 d). According to sensory evaluation, the shelf life of tilapia fillets was extended by 6 d in the EGT group. Therefore, EGT improved the quality of cryopreserved tilapia fillets and could be considered as a potential method for fish fillet preservation.


Assuntos
Materiais Biomiméticos/química , Catequina/análogos & derivados , Armazenamento de Alimentos/métodos , Gelatina/química , Alimentos Marinhos/análise , Aeromonas/efeitos dos fármacos , Animais , Aminas Biogênicas/análise , Materiais Biomiméticos/farmacologia , Catequina/química , Peroxidação de Lipídeos/efeitos dos fármacos , Desnaturação Proteica/efeitos dos fármacos , Proteínas/química , Pseudomonas/efeitos dos fármacos , Alimentos Marinhos/microbiologia , Paladar/efeitos dos fármacos , Temperatura Ambiente
12.
Carbohydr Polym ; 228: 115386, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31635725

RESUMO

Biopolymer-based materials are potential candidates for food coatings application. In this study, pomegranate (Punica granatum L.) peel extract (PPE) at different concentrations was incorporated to chitosan/gelatin gels and the rheological, antioxidant and structural properties were evaluated. Due to its high phenolic content, PPE enhanced the antioxidant capacity of chitosan/gelatin mixtures. PPE addition extended linear viscoelastic range and enabled the samples to easily flow under the applied shear rate. Rheological properties indicated that both viscosity and activation energy of materials containing natural compounds are highly dependent on temperature. Scanning electron microscopy (SEM) images revealed the influence of PPE concentration in the scaffolds pores size. Findings of this study proved that PPE was capable to improve the functional characteristics of chitosan/gelatin-based materials enhancing the desired properties for their potential application as food coatings.


Assuntos
Quitosana/química , Frutas/química , Gelatina/química , Géis/química , Fenóis/química , Extratos Vegetais/química , /metabolismo , Antioxidantes/química , Materiais Biocompatíveis/química , Reologia
13.
J Agric Food Chem ; 68(3): 759-768, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31841328

RESUMO

In this study, we investigated the antihypertensive effects in vitro and in vivo of novel angiotensin-converting enzyme inhibitory (ACEI) peptides purified and identified from bovine bone gelatin hydrolysate (BGH). Thirteen ACEI peptides were identified from BGH, and among which, RGL-(Hyp)-GL and RGM-(Hyp)-GF exhibited high ACE inhibition with IC50 values of 1.44 and 10.23 µM. Molecular docking predicted that RGM-(Hyp)-GF and ACE residues of Glu384, His513, and Lys511 formed hydrogen-bonding interactions at distances of 2.57, 2.99, and 2.42 + 3.0 Å. RGL-(Hyp)-GL formed hydrogen bonds with Lys511 and Tyr523 and generated hydrogen-bonding interactions with His387 and Glu411 in the zinc(II) complexation motif at distances of 2.74 and 3.03 + 1.93 Å. The maximal decrements in systolic blood pressure in spontaneously hypertensive rats induced by one-time gavage of RGL-(Hyp)-GL and RGM-(Hyp)-GF at 30 mg/kg were 31.3 and 38.6 mmHg. RGL-(Hyp)-GL had higher enzyme degradation resistance than that of RGM-(Hyp)-GF in vitro incubation in rat plasma, and they were sequentially degraded into pentapeptides and tetrapeptides within 2 h. Our results indicate that BGH can serve as a nutritional candidate to control blood pressure.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/química , Anti-Hipertensivos/química , Osso e Ossos/química , Gelatina/química , Peptídeos/química , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/isolamento & purificação , Pressão Sanguínea/efeitos dos fármacos , Bovinos , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Masculino , Simulação de Acoplamento Molecular , Peptídeos/administração & dosagem , Peptídeos/isolamento & purificação , Peptidil Dipeptidase A/química , Hidrolisados de Proteína/química , Ratos , Ratos Endogâmicos SHR
14.
Food Chem ; 309: 125769, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31734007

RESUMO

Phenolic compounds are known to bind non-covalently with starch, but the impact of this interaction on the stability of the phenolic compounds through processing and digestion has received little attention. In this study, we examined the recovery of intact phenolic compounds (gallic acid-GA, catechin-CAT and epigallocatechin gallate-EGCG) from processed and digested porridges with different formulations (starch or starch/protein). We observed that phenolics were less degraded in presence of starch only than in presence of starch + proteins. This protection seemed to be linked to the ability of the phenolic compounds to form V-type inclusion complexes with starch, with GA, CAT and EGCG in decreasing order of protection. This work could influence formulation of functional cereal-based foods containing phenolic compounds in order to maximize their retention.


Assuntos
Manipulação de Alimentos/métodos , Fenóis/química , Proteínas/química , Amido/química , Catequina/análogos & derivados , Catequina/química , Catequina/metabolismo , Ácido Gálico/química , Ácido Gálico/metabolismo , Gelatina/química , Gelatina/metabolismo , Fenóis/metabolismo , Proteínas/metabolismo , Amido/metabolismo
15.
Food Chem ; 309: 125764, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31771916

RESUMO

Coating fruits surface with biodegradable films obtained from starch is an alternative to delay the fruit ripening process. This study aimed to develop a biodegradable film from a polymer blend consisting of natural cassava starch, casein, and gelatin, and using sorbitol as the plasticizer. Among all the prepared biodegradable films (BFs), the one with desirable results in thickness, opacity, solubility, and water vapor transmission rate (WVTR) analyzes was based on a high concentration of starch, and casein, and low concentration of gelatin. Also, this film had the lowest solubility among all of them. Guava fruit coated with this film showed a two-day increase in shelf-life when compared to non-coated guavas. The increase in shelf-life was due to the extremely low water vapor transmission rate of the films, decreasing the fruits' mass loss, and, consequently, retarding their senescence. These results indicate that the biodegradable film is a promising material for fruit coating.


Assuntos
Caseínas/química , Gelatina/química , Amido/química , Frutas/química , Permeabilidade , Psidium/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química
16.
Food Chem ; 302: 125267, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31400701

RESUMO

A study was to determine the correlation between the fine structure and the physicochemical properties of pre-gelatinized corn starch (PGCS) and the quality of noodles with added PGCS. Drum-dried corn starch (DDCS) and extrusion-cooked corn starch (ECCS) were used. The results revealed that the cold-water viscosity of ECCS and DDCS was about 10 and 100 times greater, respectively, than that of native corn starch (NCS), and the gel strength of DDCS was 1.67 times greater than that of ECCS. The average hydrodynamic radius of whole molecular (R¯h) and Ap were approximately half that of native corn starch in ECCS. Dough sheets prepared with various concentrations of PGCS (5-10%, w/w) had significantly greater tensile strength, and the addition of PGCS significantly increased the smoothness of the cooked noodles. DDCS was better than ECCS for increasing the noodles' processing quality.


Assuntos
Culinária , Qualidade dos Alimentos , Gelatina/química , Amido/química , Farinha/análise , Viscosidade , Água/química
17.
Nature ; 575(7781): 169-174, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31666696

RESUMO

Two dry surfaces can instantly adhere upon contact with each other through intermolecular forces such as hydrogen bonds, electrostatic interactions and van der Waals interactions1,2. However, such instant adhesion is challenging when wet surfaces such as body tissues are involved, because water separates the molecules of the two surfaces, preventing interactions3,4. Although tissue adhesives have potential advantages over suturing or stapling5,6, existing liquid or hydrogel tissue adhesives suffer from several limitations: weak bonding, low biological compatibility, poor mechanical match with tissues, and slow adhesion formation5-13. Here we propose an alternative tissue adhesive in the form of a dry double-sided tape (DST) made from a combination of a biopolymer (gelatin or chitosan) and crosslinked poly(acrylic acid) grafted with N-hydrosuccinimide ester. The adhesion mechanism of this DST relies on the removal of interfacial water from the tissue surface, resulting in fast temporary crosslinking to the surface. Subsequent covalent crosslinking with amine groups on the tissue surface further improves the adhesion stability and strength of the DST. In vitro mouse, in vivo rat and ex vivo porcine models show that the DST can achieve strong adhesion between diverse wet dynamic tissues and engineering solids within five seconds. The DST may be useful as a tissue adhesive and sealant, and in adhering wearable and implantable devices to wet tissues.


Assuntos
Adesividade , Adesivos/química , Coração , Pulmão , Próteses e Implantes , Estômago , Molhabilidade , Resinas Acrílicas/química , Animais , Quitosana/química , Reagentes para Ligações Cruzadas/química , Dessecação , Gelatina/química , Coração/anatomia & histologia , Hidrogéis/química , Ligações de Hidrogênio , Pulmão/anatomia & histologia , Pulmão/química , Camundongos , Ratos , Eletricidade Estática , Estômago/anatomia & histologia , Estômago/química , Suínos , Fatores de Tempo , Água/análise , Água/química , Dispositivos Eletrônicos Vestíveis
18.
J Phys Chem Lett ; 10(24): 7745-7752, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31773960

RESUMO

Logic gate functions built with nonvolatile resistive switching and thermoresponsive memory based on biologic proteins were investigated. The "NAND" and "NOR" functions of logic gates in soya protein devices have been built at room temperature by their nonvolatile ternary WORM resistive switching behaviors. Furthermore, heating the devices from room temperature to 358 K results in a switch from tristable state to bistable state WORM resistive switching behavior, indicating that the thermoresponsiveness can be efficiently memorized. The biologic transient nonvolatile memory device consisting of soya protein is illustrated. This device exhibits a long data retention time (104 s) and significant HRS/LRS ratio (∼105); the transient response of the current to voltage of an as-fabricated device is also explored. The soya protein based memory device on a gelatin film substrate is also assessed to validate the feasibility of degradation and biological compatibility for the implantable biological electronic device, that is, innoxious and avirulent to the human body. This can offer alternative avenues for exploring prospective bioelectronic devices.


Assuntos
Dispositivos de Armazenamento em Computador , Desenho de Equipamento/instrumentação , Proteínas de Plantas/química , Soja/química , Condutividade Elétrica , Eletrodos , Gelatina/química , Temperatura Ambiente
19.
Chem Asian J ; 14(24): 4837-4846, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31756283

RESUMO

Three-dimensional (3D) scaffolds formed from natural biopolymers gelatin and chitosan that are chemically modified by galactose have shown improved hepatocyte adhesion, spheroid geometry and functions of the hepatocytes. Galactose specifically binds to the hepatocytes via the asialoglycoprotein receptor (ASGPR) and an increase in galactose density further improves the hepatocyte proliferation and functions. In this work, we aimed to increase the galactose density within the biopolymeric scaffold by physically blending the biopolymers chitosan and gelatin with an amphiphlic ß-galactose polypeptide (PPO-GP). PPO-GP, is a di-block copolymer with PPO and ß-galactose polypeptide, exhibits lower critical solution temperature and is entrapped within the scaffold through hydrophobic interactions. The uniform distribution of PPO-GP within the scaffold was confirmed by fluorescence microscopy. SEM and mechanical testing of the hybrid scaffolds indicated pore size, inter connectivity and compression modulus similar to the scaffolds made from 100 % biopolymer. The presence of the PPO-GP on the surface of the scaffold was tested monitoring the interaction of an analogous mannose containing PPO-GP scaffold and the mannose binding lectin Con-A. In vitro cell culture experiments with HepG2 cells were performed on GLN-GP and CTS-GP and their cellular response was compared with GLN and CTS scaffolds for a period of seven days. Within three days of culture the Hep G2 cells formed multicellular spheroids on GLN-GP and CTS-GP more efficiently than on the GLN and CTS scaffolds. The multicellular spheroids were also found to infiltrate more in GLN-GP and CTS-GP scaffolds and able to maintain their round morphology as observed by live/dead and SEM imaging.


Assuntos
Quitosana/química , Gelatina/química , Glicoproteínas/química , Hepatócitos/metabolismo , Polímeros/química , Propilenoglicóis/química , Tecidos Suporte/química , Animais , Módulo de Elasticidade , Galactosídeos/química , Células Hep G2 , Humanos , Hidrogéis/síntese química , Hidrogéis/química , Esferoides Celulares/metabolismo , Suínos , Engenharia Tecidual/métodos
20.
AAPS PharmSciTech ; 20(8): 322, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31650263

RESUMO

The objectives of this work were to prepare a 5 wt% lidocaine-diclofenac ionic liquid drug-loaded gelatin/poly(vinyl alcohol) transdermal patch using a freeze/thaw method and to evaluate its physicochemical properties, in vitro release of lidocaine and diclofenac, and stability test. The lidocaine-diclofenac ionic liquid drug was produced by the ion pair reaction between the hydrochloride salts of lidocaine and the sodium salts of diclofenac. The thermal properties of the final drug product were significantly changed from the primary drugs. The ionic liquid drug could be dissolved in water and mixed in a polymer solution. The resulting transdermal patch was then exposed to 10 cycles of freezing and thawing preparation at - 20°C for 8 h and at 25°C for 4 h, respectively. As a result, it was found that the lidocaine-diclofenac ionic liquid drug-loaded transdermal patch showed good physicochemical properties and could feasibly be used in pharmaceutical applications. The lidocaine-diclofenac ionic liquid drug was not affected by the properties of the transdermal patch due to the lack of chemical interaction between polymer base and drug. The high drug release values of both lidocaine and diclofenac were controlled by the gelatin/poly(vinyl alcohol) transdermal patch. The patch showed good stability over the study period of 3 months when kept at 4°C or under ambient temperature.


Assuntos
Diclofenaco/farmacocinética , Gelatina/farmacocinética , Líquidos Iônicos/farmacocinética , Lidocaína/farmacocinética , Álcool de Polivinil/farmacocinética , Adesivo Transdérmico , Administração Cutânea , Anestésicos Locais/química , Anestésicos Locais/farmacocinética , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacocinética , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Diclofenaco/química , Combinação de Medicamentos , Liberação Controlada de Fármacos , Congelamento , Gelatina/química , Líquidos Iônicos/química , Lidocaína/química , Álcool de Polivinil/química
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