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1.
J Appl Oral Sci ; 28: e20190499, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348441

RESUMO

Enzymatic degradation of the hybrid layer can be accelerated by the activation of dentin metalloproteinases (MMP) during the bonding procedure. MMP inhibitors may be used to contain this process. Objective To evaluate the degree of conversion (DC%), dentin bond strength (µTBS) (immediate and after 1 year of storage in water), and nanoleakage of an experimental (EXP) and a commercial (SB) adhesive system, containing different concentrations of the MMP inhibitor GM1489: 0, 1 µM, 5 µM and 10 µM. Methodology DC% was evaluated by FT-IR spectroscopy. Dentin bond strength was evaluated by µTBS test. Half of beams were submitted to the µTBS test after 24 h and the other half, after storage for 1 year. From each tooth and storage time, 2 beams were reserved for nanoleakage testing. Data were analyzed using ANOVA and Tukey's test to compare means (α=0.05). Results All adhesive systems maintained the µTBS after 1 year of storage. Groups with higher concentrations of inhibitor (5 µM and 10 µM) showed higher µTBS values than groups without inhibitor or with 1 µM. The nanoleakage values of all groups showed no increase after 1 year of storage and values were similar for SB and EXP groups, in both storage periods. The inhibitor did not affect the DC% of the EXP groups, but the SB5 and SB10 groups showed higher DC% values than those of SB0 and SB1. Conclusions The incorporation of GM1489 in the adhesive systems had no detrimental effect on DC%. The concentrations of 5 µM GM1489 for SB and 5 µM or 10 µM for EXP provided higher µTBS than groups without GM1489, in the evaluation after 1 year of storage; whereas the concentration of inhibitor did not affect adhesive systems nanoleakage.


Assuntos
Cimentos Dentários/química , Dentina/química , Inibidores de Metaloproteinases de Matriz/química , Metacrilatos/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Análise de Variância , Colagem Dentária/métodos , Corrosão Dentária/métodos , Infiltração Dentária , Dentina/efeitos dos fármacos , Humanos , Teste de Materiais , Valores de Referência , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Estatísticas não Paramétricas , Propriedades de Superfície , Resistência à Tração , Fatores de Tempo
2.
J Nanobiotechnology ; 18(1): 17, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964393

RESUMO

This study aimed to develop a new colon-targeted drug delivery system via the preparation of ternary nanocomposite carriers based on organic polymer, aminoclay and lipid vesicles. Budesonide (Bud), an anti-inflammatory drug was chosen as a model drug and encapsulated into three different formulations: liposome (Bud-Lip), aminoclay-coated liposome (AC-Bud-Lip), and Eudragit® S100-aminoclay double coated liposome (EAC-Bud-Lip). The formation of the aminoclay-lipid vesicle nanocomposite was confirmed by energy dispersive X-ray spectrum, transmission electron microscopy, and Fourier-transform infrared spectroscopy. All formulations were produced with a high encapsulation efficiency in a narrow size distribution. Drug release from EAC-Bud-Lip was approximately 10% for 2-h incubation at pH 1.2, implying the minimal drug release in acidic gastric condition. At pH 7.4, EAC-Bud-Lip underwent significant size reduction and exhibited drug release profiles similar to that from AC-Bud-Lip, implying the pH-dependent removal of the outer coating layer. Compared to free Bud solution, EAC-Bud-Lip achieved a higher drug uptake in Caco-2 cells and exhibited a stronger inhibition of TNF-α and IL-6 secretion in LPS-stimulated Raw264.7 cells. Furthermore, a bio-distribution study in mice demonstrated that Eudragit® S100-aminoclay dual coating led to a higher colonic distribution with a longer residence time, which correlated well with the delayed systemic drug exposure in rats. Taken together, the present study suggests that the ternary nanocomposite carrier consisting of Eudragit® S100, aminoclay, and lipid vesicle might be useful as an effective colon-targeted drug delivery system.


Assuntos
Anti-Inflamatórios/química , Budesonida/química , Argila/química , Colo/metabolismo , Lipídeos/química , Lipossomos/química , Nanocompostos/química , Animais , Anti-Inflamatórios/farmacocinética , Budesonida/farmacocinética , Células CACO-2 , Liberação Controlada de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Interleucina-6/metabolismo , Masculino , Camundongos , Ácidos Polimetacrílicos/química , Células RAW 264.7 , Ratos Sprague-Dawley , Solubilidade , Propriedades de Superfície , Distribuição Tecidual , Fator de Necrose Tumoral alfa/metabolismo
3.
J Med Microbiol ; 69(2): 298-308, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31976854

RESUMO

Introduction. Periodontitis is among the most widespread oral bacterial diseases affecting 15-20% of the world population.Aim. This study aimed to develop dental floss impregnated with povidone-iodine (PVP-I) as an antimicrobial delivery system against periodontopathogenic bacteria in a planktonic form and within biofilms.Methods. Identical lengths of dental floss impregnated with PVP-I formulations were placed on agar along with previously grown periodontal pathogens. The bioactivity of the dental floss was investigated by response-surface methodology. In order to explore the antibacterial activity of the selected formulation and the potential application in the prevention and treatment of plaque-caused diseases such as periodontitis and caries, the antibacterial and anti-biofilm activity of the selected PVP-I formulation against pathogenic bacteria were investigated.Results. The results indicated that the coating formulation containing Eudragit L-100 2.90 %, PVP-I 24.58 % and PEG 400 3.73 % had antimicrobial activity for all pathogens. The mechanism of this formulation involved disruption of bacterial cell membranes. Moreover, this formulation inhibited the formation of oral pathogenic biofilms.Conclusion. It was concluded that Eudragit L-100 and PVP-I-coated dental floss represented a potential therapeutic agent to prevent periodontal diseases and dental caries and exhibited non-toxicity to periodontal ligament cells.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Periodontite/prevenção & controle , Ácidos Polimetacrílicos/química , Povidona-Iodo/farmacologia , Antibacterianos/química , Bactérias/crescimento & desenvolvimento , Dispositivos para o Cuidado Bucal Domiciliar , Sistemas de Liberação de Medicamentos , Humanos , Periodontite/microbiologia , Povidona-Iodo/química
4.
Anal Chim Acta ; 1093: 142-149, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31735207

RESUMO

α-amanitin is the most toxic amanita in mushrooms with lethal dose to humans around 0.1 mg. Kg-1. Hence, early identification of the poison would improve survival rates and prevent lethal poisoning cases. In this study, molecularly imprinted photonic crystal (MIPC) sensor was prepared by combining molecular imprinting with photonic crystal templates and tested towards the detection of α-amanitin. In this process, synthesized moiety of α-amanitin was utilized as template, dispersed SiO2 colloidal photonic crystal as carrier, methacrylic acid (MAA) as functional monomer, and ethylene glycol dimethacrylate (EDGMA) as crosslinker. The adsorption behavior of MIPC towards α-amanitin in ethanol solution showed shifts in diffraction peaks of MIPC upon binding with α-amanitin molecules. The reflection peak wavelength varied linearly with α-amanitin concentration according to the correlation formula: λ = 15.417c+489.17 (R2 = 0.9985). The recognition process was accompanied by gradual color change in MIPC film. The prepared MIPC sensor possessed wide linear range (10-9-10-3 mg L-1), change in visual color, low detection limit (10-10 mg L-1), short response time (2 min), and good reusability. The MIPC film was then tested towards the detection of α-amanitin in real biological samples (mushroom, urine, and serum) and showed reasonable shift in diffraction peaks and color change upon soaking in solutions spiked with α-amanitin at 10-6 mg L-1 and 10-3 mg L-1, suggesting the suitability of the film for the rapid identification of α-amanitin in complex sample matrices. Overall, the proposed sensor looks promising for the rapid identification of α-amanitin in clinical analysis and food poisoning.


Assuntos
Alfa-Amanitina/análise , Colorimetria/métodos , Dióxido de Silício/química , Agaricales/química , Alfa-Amanitina/sangue , Alfa-Amanitina/urina , Feminino , Humanos , Limite de Detecção , Impressão Molecular/métodos , Ácidos Polimetacrílicos/química , Reprodutibilidade dos Testes
5.
Anal Chim Acta ; 1093: 160-167, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31735210

RESUMO

In this study, poly(butyl methacrylate-co-ethyleneglycol dimethacrylate) polymeric monoliths were in situ developed within 0.75 mm i.d. poly(ethylene-co-tetrafluoroethylene) (ETFE) tubing by UV polymerization via three different free-radical initiators (α,α'-azobisisobutyronitrile (AIBN), 2,2-dimethoxy-2-phenylacetophenone (DMPA) and 2-methyl-4'-(methylthio)-2-morpholinopropiophenone (MTMPP). The influence of the nature of each photo-initiator and irradiation time on the morphological features of the polymer was investigated by scanning electron microscopy, and the chromatographic properties of the resulting microbore columns were evaluated using alkyl benzenes as test substances. The beds photo-initiated with MTMPP gave the best performance (minimum plate heights of 38 µm for alkyl benzenes) and exhibited a satisfactory reproducibility in the chromatographic parameters (RSD < 11%). These monolithic columns were also successfully applied to the separation of phenylurea herbicides, proteins and a tryptic digest of ß-casein.


Assuntos
Acetofenonas/química , Cromatografia Líquida de Alta Pressão/instrumentação , Morfolinas/química , Nitrilos/química , Ácidos Polimetacrílicos/química , Politetrafluoretileno/análogos & derivados , Propiofenonas/química , Acetofenonas/efeitos da radiação , Caseínas/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Herbicidas/isolamento & purificação , Metacrilatos/química , Morfolinas/efeitos da radiação , Nitrilos/efeitos da radiação , Fragmentos de Peptídeos/isolamento & purificação , Compostos de Fenilureia/isolamento & purificação , Polimerização , Ácidos Polimetacrílicos/síntese química , Politetrafluoretileno/química , Propiofenonas/efeitos da radiação , Raios Ultravioleta
6.
Int J Nanomedicine ; 14: 7933-7946, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31686819

RESUMO

Background: Human trials combining external radiotherapy (RT) and metallic nanoparticles are currently underway in cancer patients. For internal RT, in which a radioisotope such as radioiodine is systemically administered into patients, there is also a need for enhancing treatment efficacy, decreasing radiation-induced side effects and overcoming radio-resistance. However, if strategies vectorising radioiodine through nanocarriers have been documented, sensitizing the neoplasm through the use of nanotherapeutics easily translatable to the clinic in combination with the standard systemic radioiodine treatment has not been assessed yet. Method and materials: The present study explored the potential of hybrid poly(methacrylic acid)-grafted gold nanoparticles to improve the performances of systemic 131I-mediated RT on cancer cells and in tumor-bearing mice. Such nanoparticles were chosen based on their ability previously described by our group to safely withstand irradiation doses while exhibiting good biocompatibility and enhanced cellular uptake. Results: In vitro clonogenic assays performed on melanoma and colorectal cancer cells showed that poly(methacrylic acid)-grafted gold nanoparticles (PMAA-AuNPs) could efficiently lead to a marked tumor cell mortality when combined to a low activity of radioiodine, which alone appeared to be essentially ineffective on tumor cells. In vivo, tumor enrichment with PMAA-AuNPs significantly enhanced the killing potential of a systemic radioiodine treatment. Conclusion: This is the first report of a simple and reliable nanomedicine-based approach to reduce the dose of radioiodine required to reach curability. In addition, these results open up novel perspectives for using high-Z metallic NPs in additional molecular radiation therapy demonstrating heterogeneous dose distributions.


Assuntos
Ouro/química , Radioisótopos do Iodo/uso terapêutico , Nanopartículas Metálicas/química , Polímeros/química , Animais , Morte Celular , Linhagem Celular Tumoral , Feminino , Humanos , Melanoma Experimental/radioterapia , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/ultraestrutura , Camundongos Endogâmicos BALB C , Camundongos Nus , Ácidos Polimetacrílicos/química , Radiossensibilizantes/farmacologia , Dosagem Radioterapêutica , Simportadores/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Pharm Res ; 36(12): 175, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31677137

RESUMO

PURPOSE: Traditional methods for estimating drug-polymer solubility either require fast dissolution in the polymeric matrix, rapid re-crystallization kinetics from supersaturated states or derive from regular solution theories. In this work, we present a new method for determining drug solubility, purely based on thermodynamic considerations, that uses only experimental data from DSC for calculations. METHODS: The new thermodynamic model presented combines DSC analysis and application of Hess's law to determine free energies of conversion of binary mixtures to amorphous solid dispersions, free energies of mixing as well as solubility as a function of temperature. The model drug indomethacin and polymers HPMCAS LF, PVP K29/32 and Eudragit EPO were used in these studies. RESULTS: Free energies were calculated as a function of temperature, for different drug-polymer compositions and the results show that HPMCAS LF solid dispersion with high drug content are less thermodynamically favorable compared to other polymer systems. Solubility of indomethacin in HPMCAS LF, PVP K29/32 and Eudragit EPO was 24, 55 and 56% w/w, respectively, at 25°C. CONCLUSIONS: The thermodynamic model presented has great advantages over traditional methods. It does not require estimation of any interaction parameters, it is almost assumption-free and uses only thermal data for calculations.


Assuntos
Composição de Medicamentos/métodos , Indometacina/química , Modelos Moleculares , Polímeros/química , Cristalização , Estabilidade de Medicamentos , Cinética , Metilcelulose/análogos & derivados , Metilcelulose/química , Ácidos Polimetacrílicos/química , Povidona/química , Solubilidade , Termodinâmica , Temperatura de Transição
8.
Mikrochim Acta ; 186(12): 822, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31754802

RESUMO

A nanosorbent composed of magnetite nanoparticles, graphene oxide and a molecularly imprinted polymer (Fe3O4@SiO2-NH2/GOx/MIP) was synthesized and applied to simultaneous extraction of cephalexin, cefazolin and cefoperazone from milk. The use of magnetite nanoparticles enables fast extraction by using an external magnet. The use of graphene oxide increases extraction affinity, and the MIP improves selectivity. Extraction efficiency was optimized by investigating the effects of the template-to-monomer and cross-linker ratios, the desorption condition, extraction time, salting-out effect, stirring rate, sample volume and amount of adsorbent. The cephalosporins were quantified by using HPLC. Under optimum condition, the linear range of the method extends from 2.5 to 100 µg L-1 for cephalexin and cefazolin, and from 5.0 to 100 µg L-1 for cefoperazone. The limits of detection are 2.5 µg L-1 for cephalexin and cefazolin, and 5 µg L-1 for cefoperazone. The adsorbent was applied to the extraction of cephalosporins from milk, with recoveries in a range from 80.2 to 111.7% and with RSDs of <8.5%. Graphical abstractSchematic representation of a nanocomposite adsorbent consisting of magnetic molecularly imprinted polymer and graphene oxide (GOx). Integrating of magnetite nanoparticles, GOx and high specificity of MIP, the method exhibited a rapid, high extraction efficiency, good selectivity for multi-residue analysis of cephalosporins.


Assuntos
Cefalosporinas/análise , Grafite/química , Nanopartículas de Magnetita/química , Ácidos Polimetacrílicos/química , Adsorção , Animais , Técnicas Biossensoriais , Bovinos , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Fenômenos Magnéticos , Leite/química , Impressão Molecular , Sensibilidade e Especificidade , Dióxido de Silício/química , Extração em Fase Sólida
9.
Molecules ; 24(19)2019 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-31590469

RESUMO

For this paper, the self-healing ability of poly(methacrylate)s crosslinked via reversible urea bonds was studied in detail. In this context, the effects of healing time and temperature on the healing process were investigated. Furthermore, the impact of the size of the damage (i.e., area of the scratch) was monitored. Aging processes, counteracting the self-healing process, result in a decrease in the mechanical performance. This effect diminishes the healing ability. Consequently, the current study is a first approach towards a detailed analysis of self-healing polymers regarding the influencing parameters of the healing process, considering also possible aging processes for thermo-reversible polymer networks.


Assuntos
Reagentes para Ligações Cruzadas/química , Ácidos Polimetacrílicos/química , Ureia/química , Conformação Molecular , Polimerização , Temperatura
10.
Anal Chim Acta ; 1089: 78-89, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31627821

RESUMO

Novel molecularly imprinted polymer (MIP) for metformin was synthesized on the surface of magnetic multi-walled carbon nanotubes (MMWCNTs) as the support. Metformin was used as the template, methacrylic acid (MAA) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the cross-linker and 2,2'-azoisobutyronitrile (AIBN) as the initiator. The synthesized composite was characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and Fourier transform infrared spectroscopy (FTIR). The surface molecularly imprinted composite was used for magnetic solid phase microextraction (MSPME) of metformin before its chemiluminescence (CL) determination and its capability was compared with non-imprinted polymer (NIP). The central composite design was used for optimization as well as consideration of possible interaction of effective variables on extraction. Under the optimized conditions, the developed method exhibited the linear dynamic range of 0.5-50.0 µg L-1 with a detection limit of 0.13 µg L-1 and enhancement factor of 195.3 for the preconcentration of 100 mL of the sample and 500 µL of an eluent. The intra- and inter-day relative standard deviations (RSD%) at 5.0 µg L-1 level of metformin (n = 6) were 3.7 and 4.9%, respectively. The maximum adsorption capacity of the sorbent was found to be 80.0 mg g-1, the adsorption of metformin was endothermic and spontaneous and followed the Langmuir isotherm model. The adsorption kinetic was also found to be best fitted with the pseudo-second-order model. The designed method was successfully applied to the extraction and determination of metformin in biological fluids and water samples.


Assuntos
Metformina/análise , Nanotubos de Carbono/química , Microextração em Fase Sólida/métodos , Poluentes Químicos da Água/análise , Adsorção , Água Potável/análise , Cinética , Limite de Detecção , Metformina/sangue , Metformina/urina , Impressão Molecular , Ácidos Polimetacrílicos/síntese química , Ácidos Polimetacrílicos/química , Água do Mar/análise , Poluentes Químicos da Água/sangue , Poluentes Químicos da Água/urina
11.
J Oleo Sci ; 68(9): 847-854, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31484901

RESUMO

Metal nanoparticles have the ability to remove superoxide via changes in the surface electronic states at the large surface area. Gold, silver, and platinum nanoparticles were prepared in the presence of three sugar-based nonionic surfactants using NaBH4 as a reducing agent. The surfactants (glycosyloxyethyl methacrylate: xGEMA) contain sugar oligomers of various lengths (x), are biodegradable, and act as protecting groups for the nanoparticles. Three types of xGEMA were used: dodecyl and hexadecyl chains containing amphiphilic oligomers (C12-3.0GEMA and C16-3.2GEMA) and multi-dodecyl chain with multiple sugar side chains (1.8C12-4.7GEMA). We found that the type of nonionic surfactant affected the size of the nanoparticles. The average size of the gold, silver, and platinum nanoparticles ranged from 1.9 to 6.6 nm depending on the surfactant. The trend in the size of gold nanoparticles in relation to the chosen surfactants was different from that for the silver and platinum nanoparticles. Moreover, the gold nanoparticles did not show effective antioxidant activity for superoxide, whereas the silver and platinum nanoparticles removed superoxide to a certain extent. The general order for superoxide scavenging activity increased in the following order: gold < platinum < silver. In particular, the largest size of silver nanoparticles capped with C16-3.2GEMA had a similar ability for the removal of superoxide as superoxide dismutase (ca. 3999 unit/mg) on the basis of the mass concentration.


Assuntos
Depuradores de Radicais Livres/química , Glucosídeos/química , Nanopartículas Metálicas/química , Ácidos Polimetacrílicos/química , Superóxidos/química , Tensoativos/química , Animais , Bovinos , Ouro/química , Tamanho da Partícula , Platina/química , Prata/química , Superóxido Dismutase/química
12.
Acta Diabetol ; 56(12): 1323-1331, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31494747

RESUMO

AIMS: Nephropathic patients show higher levels of advanced glycation end products (AGEs) and oxidized human serum albumin (HSAox) compared to healthy subjects. These two classes of compounds are formed as the result of oxidative insults; for this reason, they can be useful oxidative stress biomarkers. The present study examines the variation of AGEs and HSAox in hemodialysis (HD) patients before and after dialysis session, evaluating the impact of different dialytic techniques and filters on their removal. METHODS: A total of 50 healthy subjects (control group) and 130 HD patients were enrolled in the study. Hemodialysis patients were subdivided based on dialytic techniques: 109 in diffusive technique and 22 in convective technique. We monitored HSAox, AGEs and other laboratory parameters at early morning in healthy subjects and in HD patients before and after the dialysis procedures. RESULTS: The level of HSAox decreases after a single dialytic session (from 58.5 ± 8.8% to 41.5 ± 11.1%), but the concentration of total AGEs increases regardless of adopted dialytic techniques (from 6.8 ± 5.2 µg/ml to 9.2 ± 4.4 µg/ml). In our study, levels of HSAox and total AGEs are similar in diabetic and non-diabetic HD patients. The increase in total AGEs after dialysis was only observed using polysulfone filters but was absent with polymethacrylate filters. CONCLUSIONS: HSAox is a simple and immediate method to verify the beneficial effect of a single dialysis session on the redox imbalance, always present in HD patients. Total AGEs assayed by ELISA procedure seem to be a less reliable biomarker in this population.


Assuntos
Biomarcadores , Produtos Finais de Glicação Avançada/sangue , Diálise Renal , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/terapia , Albumina Sérica Humana/metabolismo , Biomarcadores/análise , Biomarcadores/sangue , Estudos de Casos e Controles , Nefropatias Diabéticas/sangue , Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/epidemiologia , Nefropatias Diabéticas/terapia , Feminino , Produtos Finais de Glicação Avançada/análise , Humanos , Masculino , Pessoa de Meia-Idade , Oxirredução , Estresse Oxidativo/fisiologia , Polímeros/química , Ácidos Polimetacrílicos/química , Prognóstico , Diálise Renal/métodos , Diálise Renal/estatística & dados numéricos , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/epidemiologia , Albumina Sérica Humana/análise , Sulfonas/química , Resultado do Tratamento
13.
Drug Dev Ind Pharm ; 45(11): 1807-1820, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31489829

RESUMO

This study is using the targeted approach and anti-inflammatory action of the probiotic biomass to lessen the side effects of therapeutic agents of ulcerative colitis. The aim of the present study is to prepare mesalamine loaded eudragit S-100 with probiotic microparticles by spray drying method. The in-vitro release of the optimized formulation was 90.55 ± 2.42 in 24 hr, which display controlled drug release of mesalamine at a particular region. Mesalamine loaded eudragit S-100 with probiotic microparticles (F12) presented average particle size of 4.91 µm. The statistical analysis was done by one way ANOVA and then comparison test of Bonferroni was done and p values <.05 were considered as significant. The effects of spray dried microparticles over inflamed Caco-2 cell were also evaluated by determining the concentration of IL-8. From in-vivo study it was seen that pretreatment of mesalamine with probiotic prevents DNBS (Dinitrobenzenesulfonic acid) induced colitis in rats and represents protective action against ulcerative colitis because of its antioxidant and anti-inflammatory actions. The results give the foundation for a combination of targeted approach along with the anti-inflammatory potential of the probiotic which might help to decrease the problems which are seen with the traditional cure and management of ulcerative colitis.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Colite Ulcerativa/tratamento farmacológico , Composição de Medicamentos/métodos , Mesalamina/administração & dosagem , Probióticos/administração & dosagem , Animais , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/farmacocinética , Benzenossulfonatos/toxicidade , Células CACO-2 , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/patologia , Colo/efeitos dos fármacos , Colo/patologia , Modelos Animais de Doenças , Portadores de Fármacos/química , Combinação de Medicamentos , Liberação Controlada de Fármacos , Feminino , Humanos , Lactobacillus acidophilus , Masculino , Mesalamina/efeitos adversos , Mesalamina/farmacocinética , Tamanho da Partícula , Ácidos Polimetacrílicos/química , Probióticos/farmacocinética , Ratos , Ratos Wistar
14.
Chem Pharm Bull (Tokyo) ; 67(9): 906-914, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31474728

RESUMO

An aminoalkyl methacrylate copolymer, Eudragit® E (EUD-E), has gained tremendous attention as a solid dispersion carrier because it efficiently stabilizes drugs in the amorphous state. Furthermore, EUD-E remarkably enhances drug dissolution in water. This review focuses on the interaction between drugs and EUD-E in solution, which contributes to the enhancement of drug concentration. Studies examining interactions between acidic drugs and EUD-E in organic solvents have revealed that the interaction occurs predominantly by electrostatic interaction, including hydrogen bonding and dipolar interactions. Other studies on interactions in aqueous solution found evidence for strong electrostatic interactions between acidic drugs and EUD-E in ion exchange experiments. 1H-NMR studies using high-resolution magic-angle spinning, nuclear Overhauser effect spectroscopy, diffusion, and relaxation time measurements successfully identified the interaction site and strength in aqueous solution. Hydrophobic and ionic interactions occurred between drugs and EUD-E. The conformation of EUD-E, which was affected by the ionic strength and pH of the aqueous media, also influenced the interaction. The knowledge discussed in this review will be helpful in designing solid dispersion formulations with EUD-E, which will efficiently enhance drug concentration and subsequent absorption into the body.


Assuntos
Preparações Farmacêuticas/química , Ácidos Polimetacrílicos/química , Água/química , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Solubilidade , Solventes/química , Eletricidade Estática
15.
Eur J Pharm Sci ; 140: 105060, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31499171

RESUMO

The aim of the present work was to explore the feasibility of 3D printing via fused deposition modeling (FDM) in the manufacturing of a pressure-controlled drug delivery system. Eudragit® RS, a brittle polymer with pH-independent solubility, was chosen to be a suitable excipient for the 3D printing of a pressure-sensitive, capsule-like dosage form. A self-constructed piston extruder was used for hot melt extrusion (HME) of filaments made from Eudragit® RS that could be used for 3D printing. Subsequently, the printing parameters were experimentally optimized with the aid of a self-programmed software. This G-code generator allowed the simple adjustment of printing speed, temperature, extrusion multiplier and layer height. By this, capsule-shaped dosage forms with the desired mechanical properties could be obtained. The effect of physiological pressure events on the drug release behaviour from the novel dosage form was finally tested by using a biorelevant stress test device. These in vitro experiments demonstrated the rapid and quantitative release of the probe drug after applying realistic pressure events. This work illustrated that 3D printing can be an interesting technique for the production of pressure-controlled dosage forms as a new concept of oral drug delivery.


Assuntos
Preparações de Ação Retardada/química , Portadores de Fármacos/química , Ácidos Polimetacrílicos/química , Pressão , Impressão Tridimensional , Liberação Controlada de Fármacos , Excipientes/química , Concentração de Íons de Hidrogênio , Fenômenos Mecânicos , Solubilidade , Comprimidos/química , Tecnologia Farmacêutica/métodos , Temperatura
16.
Eur J Pharm Biopharm ; 144: 174-179, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31541663

RESUMO

Capsules are a widely used oral dosage form due to their simplicity and ease of manufacture. They are equally popular for both pharmaceutical and nutraceutical products and since they do not need extensive formulation development, it is a dosage form of choice for new drugs undergoing animal or clinical trials. In addition to the standard hard-gelatin or cellulose-based vegetarian capsules, functional capsules such as those with built-in gastroresistance would be of great value. In this work, commonly used enteric polymers were investigated for the production of hard-capsules. The polymers used in this study included cellulose derivatives (HPMC AS-LF and HP-55) and acrylic/methacrylic acid derivatives (EUDRAGIT L100 and S100). A range of concentrations of polymers and plasticisers were tested to optimise the formulation for the production of capsule shells with desirable physicochemical and gastroresistance characteristics. Drug release from optimised capsules produced from HPMC AS-LF, HP-55, EUDRAGIT L100 and S100 was shown to be comparable to drug release from corresponding polymer-coated tablets in both compendial and physiological bicarbonate buffer. In summary, herein we report a simple method for producing enteric capsule shells which do not need an additional coating step which, if validated at large scale, can significantly reduce the cost of manufacturing of conventional enteric coated dosage forms. These capsules are also likely to improve the inter-tablet variability in post-gastric drug release inherent in conventional dosage forms due to coating variability.


Assuntos
Cápsulas/química , Polímeros/química , Bicarbonatos/química , Tampões (Química) , Celulose/química , Química Farmacêutica/métodos , Preparações de Ação Retardada/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos/efeitos dos fármacos , Excipientes/química , Gelatina/química , Concentração de Íons de Hidrogênio , Metacrilatos/química , Metilcelulose/análogos & derivados , Metilcelulose/química , Ácidos Polimetacrílicos/química , Solubilidade/efeitos dos fármacos , Comprimidos/química
17.
J Photochem Photobiol B ; 199: 111606, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31522112

RESUMO

This study aimed to develop Eudragit® RL 100 nanocapsules loaded with desonide (DES) using açai oil (AO) or medium chain triglycerides (MCT) as oil core. Pre-formulation study showed that AO and MCT are suitable for nanocapsules preparation. The nanocapsules prepared with AO and MCT presented mean particle size around 165 and 131 nm, respectively; polydispersity index values <0.20, positive zeta potential values, drug content close to the theoretical value (0.25 mg mL-1), and DES encapsulation efficiency around 81%, regardless of the oil core (AO or MCT). Considering the photoinstability reported to DES, photodegradation studies were performed. The UV-A (365 nm) and UV-C (254 nm) photodegradation studies revealed less DES degradation when associated to the nanocapsules containing AO in comparison to those with MCT. The in vitro release study showed a biphasic release profile for both nanocapsule suspensions: an initial burst effect followed by a prolonged DES release. In addition, the formulations were considered non-phototoxic at 0.5 mg mL-1 when tested on 3 T3 murine fibroblasts and HaCaT human keratinocytes using the MTT and NRU viability assays. The irritant potential of the prepared nanocapsules and DES in free form were evaluated by HET-CAM method. All formulations were classified as slightly irritant, including the non-associate DES. In conclusion, the nanocapsule formulations developed in this study may be promising for therapeutic applications.


Assuntos
Anti-Inflamatórios/química , Desonida/química , Euterpe/química , Nanocápsulas/química , Óleos Vegetais/química , Ácidos Polimetacrílicos/química , Animais , Anti-Inflamatórios/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Desonida/farmacologia , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Humanos , Luz , Camundongos , Tamanho da Partícula , Fotólise , Óleos Vegetais/farmacologia , Suspensões/química , Triglicerídeos/química
18.
ACS Appl Mater Interfaces ; 11(38): 34707-34716, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31482705

RESUMO

It is of great significance to develop biocompatible and degradable gene carriers with stimuli-enhanced gene therapy and imaging function. In this work, low-cytotoxic polycation PGEA (ethanolamine-functionalized poly(glycidyl methacrylate))-functionalized dextran-quantum dot (QD) nanohybrids (DQ-PGEA) were proposed as safe and efficient gene carriers via a facile and feasible method. The highly water-soluble dextran gives the carrier good stability, biocompatibility, and abundant modification sites, while QDs allow fluorescence (FL) imaging. Taking advantage of the pH-responsive self-destruction characteristic introduced by Schiff base linkages, DQ-PGEA nanohybrids could not only result in enhanced gene release but also contribute to the elimination of the carriers. Reduced (nondegradable) DQ-PGEA-R nanohybrids were also synthesized as counterparts to reveal the superiority of the responsive DQ-PGEA carriers. The effectiveness of the as-prepared gene delivery systems was verified adopting the antioncogene p53 in the mouse model of breast cancer. As expected, DQ-PGEA nanohybrids demonstrated a superior gene transfection performance and antitumor inhibition compared with their counterparts. Meanwhile, the gene delivery processes could be tracked in real time to visualize the therapeutic processes and realize FL imaging-guided gene therapy. The current multifunctional stimuli-responsive nanoplatforms with the self-destruction feature are intriguing candidates to achieve enhanced gene therapy for tumor treatment.


Assuntos
Dextranos , Técnicas de Transferência de Genes , Terapia Genética , Neoplasias Mamárias Experimentais , Nanocompostos , Pontos Quânticos , Proteína Supressora de Tumor p53 , Animais , Linhagem Celular Tumoral , Dextranos/química , Dextranos/farmacologia , Células HEK293 , Humanos , Concentração de Íons de Hidrogênio , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Neoplasias Mamárias Experimentais/terapia , Camundongos , Nanocompostos/química , Nanocompostos/uso terapêutico , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/farmacologia , Pontos Quânticos/química , Pontos Quânticos/uso terapêutico , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genética
19.
ACS Appl Mater Interfaces ; 11(35): 32328-32338, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31393104

RESUMO

The influence of interfacial shear strength (IFSS) between processed short S-glass fibers (250 and 350 µm in length, 5 µm in diameter) and the dental resin (a mixture of urethane dimethacrylate and triethylene glycol dimethacrylate monomers) on the mechanical properties has been studied experimentally. The surface profile of short S-glass fibers was modified using a selective atomic level metal etching process and simple silanization process to enhance the interfacial properties. The S-glass fibers were etched in acid solutions to increase the surface roughness and selectively remove Al3+ and Mg2+ ions, which promoted the mechanical and chemical interfacial bonding reactions. The single glass fiber tensile and microdroplet pull-out tests were performed to investigate the effects of interfacial properties on the flexural strength of the resultant composites. The surface modified S-glass fibers showed an increase of 11-40% in IFSS compared to untreated glass fibers. Composites reinforced with 350 µm length glass fibers (AR-70), which were treated in piranha solution for 4 h, showed the highest improvement in overall mechanical properties, flexural strength (34.2%), modulus (9.7%), and breaking energy (51.9%), compared to the untreated fiber-reinforced composites. The modified Lewis-Nielsen equation was developed using the effective fiber length factor to accurately predict the modulus of the short fiber-reinforced composites and validated with experimental results.


Assuntos
Resinas Compostas/química , Vidro/química , Teste de Materiais , Metacrilatos/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Poliuretanos/química , Resistência ao Cisalhamento , Estresse Mecânico , Propriedades de Superfície
20.
Int J Pharm ; 569: 118581, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31369828

RESUMO

The purpose of this work was to investigate the feasibility to manufacture enteric capsules, which could be used in compounding pharmacies, by fused-deposition modeling. It is well-known that conventional enteric dip coating of capsules in community pharmacies or hospitals is a time-consuming process which is characterized by an erratic efficacy. Fused-deposition modeling was selected as a potential 3D printing method due its ease and low-cost implementation. Before starting to print the capsules, an effective sealing system was designed via a computer-aided design program. Hot melt extrusion was used to make printable enteric filaments. They were made of the enteric polymer, a plasticizer and a thermoplastic polymer, namely Eudragit® L100-55, polyethylene glycol 400 and polylactic acid, respectively. Riboflavine-5'-phosphate was selected as a coloured drug model to compare the efficacy of the 3D printed capsules to that of enteric dip coated capsules as they are currently produced in community pharmacies and hospitals. Different parameters of fabrication which could influence the dissolution profile of the model drug, such as the layer thickness or post-processing step, were studied. It was demonstrated that our 3D printed enteric capsules did not release the drug for 2 h in acid medium (pH 1.2). However, they completely dissolved within 45 min at pH 6.8 which allowed the release of a minimal amount of 85% w/w of drug as it was recommended by the European Pharmacopoeia 9th Edition for enteric products.


Assuntos
Composição de Medicamentos/métodos , Impressão Tridimensional , Cápsulas , Excipientes/química , Estudos de Viabilidade , Farmácias , Plastificantes/química , Poliésteres/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química
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