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1.
Rev. Cient. CRO-RJ (Online) ; 7(1): 31-39, Jan-Apr 2022.
Article in Portuguese | LILACS, BBO | ID: biblio-1382163

ABSTRACT

Objetivo: Avaliar o efeito de um protetor de superfície na sorção e solubilidade de cimentos de ionômero de vidro. Materiais e Métodos: Quatro materiais foram selecionados: ionômero modificado por resina encapsulado (Riva Light Cure); modificado por resina pó/líquido (Vitremer); convencional encapsulado (Equia Forte) e convencional pó/líquido (Fuji IX). Foram confeccionados 20 espécimes de cada, sendo metade com proteção superficial do Equia Forte Coat. As amostras foram mantidas em estufa a 37°C em repouso por 5 dias. Em seguida, esses foram pesados em intervalos de 24 horas. A espessura e o diâmetro foram medidos com um paquímetro digital para o cálculo do volume. Novas pesagens foram realizadas para a obtenção da massa intermediária. Em seguida, as amostras foram mantidas em repouso por 5 dias a 37°C e realizada nova pesagem. Resultados: Os dados obtidos de sorção e solubilidade foram submetidos à análise de variância (ANOVA dois fatores, material e protetor de superfície) e teste Tukey ( =0,05). Para sorção, houve diferença significativa apenas para o fator material (p<0,05), Vitremer > Equia Forte > Riva Light Cure > Fuji IX. O ionômero Fuji IX apresentou os menores valores de sorção, diferindo significativamente dos demais materiais, independentemente do uso do protetor superficial. Não houve diferença significativa para o fator proteção de superfície (p>0,05). Para solubilidade não houve diferença significativa no fator material, protetor de superfície ou interação material*protetor. Conclusão: O uso do protetor superficial não influenciou nos valores de sorção e solubilidade dos ionômeros avaliados e o ionômero convencional Fuji IX apresentou menores taxas de sorção.


Objective: evaluate the effect of a surface coating agents on the sorption and glass ionomer cements solubility. Materials and Methods: Four materials were selected: Encapsulated resin-modified ionomer (Riva Light Cure); Powder/liquid Encapsulated resin-modified (Vitremer); Encapsulated conventional (Equia Forte) and powder/ liquid conventional (Fuji IX). Twenty samples of each were made, half with surface protection of Equia Forte Coat. The samples were kept in an oven for 5 days. These were then weighed at 24-hour intervals. The thickness and diameter were measured using a digital caliper to calculate their volume. New weightings were performed to obtain the intermediate mass. Then, the samples were kept at rest for 5 days and weighed again. Results: The sorption and solubility data obtained were subjected to analysis of variance (two-way ANOVA, material and surface coating agents) and Tukey test ( =0.05). For sorption, there was a significant difference only for the material factor (p<0.05), Vitremer > Equia Forte > Riva Light Cure > Fuji IX. The Fuji IX ionomer showed the lowest sorption values, differing significantly from the other materials, regardless of the use of surface coating agents. There was no significant difference for the surface protection factor (p>0.05). For solubility there was no significant difference for the material factor, surface coating agents or material*surface coating agent interaction. Conclusion: The use of surface coating agents did not influence the sorption and solubility values of the evaluated ionomers and the conventional Fuji IX ionomer showed lower sorption rates.


Subject(s)
Solutions/chemistry , Dental Materials , Glass Ionomer Cements/chemistry , Solubility , Materials Testing , Water , Absorption
2.
Bol. latinoam. Caribe plantas med. aromát ; 21(3): 389-403, mayo 2022. ilus, tab
Article in English | LILACS | ID: biblio-1397080

ABSTRACT

This study evaluated the specific interactions between drug and polymers in amorphous spray dried dispersions (SDDs). Four Biopharmaceutics Classification System (BCS) II class drugs were evaluated. Binary and ternary SDDs were manufactured with conventional polymers and arabinogalactan. Specific interaction parameters between drug and polymer were determined using theoretical calculations and DSC data. Analytical methods were used to evaluate solid and solution state interactions. Maximum amorphous content for each formulation was calculated using DSC. Flory-Huggins Specific Interaction Parameters were calculated. Negative specific parameters were associated with solid-state interactions and improved capacity of drug in the amorphous state. Ternary SDDs containing drug, polymer, and arabinogalactan displayed similar hydrogen bonding as was observed with binary SDDs. Solution-state interactions observed in binary systems may be used in tertiary systems to improve the amorphous drug capacity and improved dissolution compared to the binary. The resultant tertiary systems are an improvement over binary drug polymer systems.


Este estudio evaluó las interacciones específicas entre el fármaco y los polímeros en dispersiones amorfas secadas por pulverización (SDD). Se evaluaron cuatro fármacos de clase II del Sistema de Clasificación Biofarmacéutica (BCS). Los SDD binarios y ternarios se fabricaron con polímeros convencionales y arabinogalactano. Los parámetros de interacción específicos entre el fármaco y el polímero se determinaron utilizando cálculos teóricos y datos de DSC. Se utilizaron métodos analíticos para evaluar las interacciones del estado sólido y de la solución. El contenido amorfo máximo para cada formulación se calculó usando DSC. Se calcularon los parámetros de interacción específicos de Flory-Huggins. Los parámetros específicos negativos se asociaron con interacciones en estado sólido y una capacidad mejorada del fármaco en el estado amorfo. Los SDD ternarios que contienen fármaco, polímero y arabinogalactano mostraron enlaces de hidrógeno similares a los observados con los SDD binarios. Las interacciones de estado de solución observadas en sistemas binarios pueden usarse en sistemas terciarios para mejorar la capacidad del fármaco amorfo y mejorar la disolución en comparación con el binario. Los sistemas terciarios resultantes son una mejora con respecto a los sistemas de polímeros de fármacos binarios.


Subject(s)
Polymers/chemistry , Solubility , Pharmaceutical Preparations/chemistry , Biological Availability , Temperature , X-Ray Diffraction , Microscopy, Electron, Scanning , Spectroscopy, Fourier Transform Infrared , Proton Magnetic Resonance Spectroscopy
3.
J. res. dent ; 10(1): 9-13, jan.-mar2022.
Article in English | LILACS, BBO | ID: biblio-1378178

ABSTRACT

Aim To evaluate physicochemical properties and semi-quantitative elemental analysis of AH Plus Jet with samples from the beginning, middle and final portions of the automix syringe system. Methodology Three experimental groups based on the source of the material used (beginning, middle and final portion) were established for each of the evaluated properties. Setting time, flow and radiopacity were evaluate following ANSI/ADA n. 57 specification. Set specimens was used in the semi-quantitative elemental analysis in an energy-dispersive X ray spectroscopy and scanning-electron microscopy (EDS/SEM). Statistical analysis was performed using one-way ANOVA followed by Tukey test (P<0.05). Results Flow, setting time, solubility and EDS/SEM tests showed no significant differences among the three portions of the automix syringe (P>0.05). Radiopacity test showed significant differences in the beginning of the syringe comparing to the middle and final portions (P<0.05). EDS/SEM analysis identified the presence of C, O, Al, Ca, Zr and W. The element Al, however, was found only in the final portion of the syringe. Conclusions The results of AH Plus Jet suggested an adequate ratio of the components, without segregation between organic and inorganic components, since the results of setting time, flow, solubility and EDS/SEM analysis presented similar values regardless of the portion of the syringe from where the sealer was taken.


Subject(s)
Humans , Root Canal Filling Materials , Solubility , Chemical Phenomena
4.
São Paulo; s.n; s.n; 2022. 70 p. tab, graf.
Thesis in English | LILACS | ID: biblio-1392313

ABSTRACT

The purpose of this work was to elaborate a diagnosis of the dissolution test in Africa in comparison with Brazil, evaluating the dissolution profile of low solubility drugs such as albendazole, ibuprofen, furosemide, glibenclamide, hydrochlorothiazide and carvedilol to ascertain their quality. The dissolution profiles were evaluated by utilizing the United States Pharmacopeia (USP). The glibenclamide medicine was evaluated according to the Food and Drug Administration (FDA), while a dissolution method was developed for the carvedilol medicine. A filter selection test for all the drugs showed that cannula is suitable for all, except for carvedilol, which is centrifuged. The various brands of Nigerian and Brazilian medicines tested showed some statistical differences. The suitable conditions that allowed the dissolution of carvedilol to be determined were the USP type II apparatus at 75 rpm containing 900 mL of acetate buffer, pH 4.5. The results of the dissolution test showed that out of the 17 different brands of Brazilian medicines and 17 different products from Nigeria, 94.12% and 58.82% passed respectively


O objetivo deste trabalho foi elaborar um diagnóstico do teste de dissolução na África em comparação ao Brasil, avaliando o perfil de dissolução de medicamentos de baixa solubilidade como albendazol, ibuprofeno, furosemida, glibenclamida, hidroclorotiazida e carvedilol para verificar sua qualidade.Os perfis de dissolução foram avaliados utilizando a Farmacopeia dos Estados Unidos (USP). O medicamento glibenclamida foi avaliado de acordo com a Food and Drug Administration (FDA), enquanto um método de dissolução foi desenvolvido para o medicamento carvedilol.Um teste de seleção de filtro para todos os medicamentos mostrou que a cânula é adequada para todos, exceto para o carvedilol, que é centrifugado. As diversas marcas de medicamentos Nigerianos e Brasileiros testadas apresentaram algumas diferenças estatísticas. As condições adequadas que permitiram a determinação da dissolução do carvedilol foram o aparelho USP tipo II a 75 rpm contendo 900 mL de tampão acetato, pH 4,5. Os resultados do teste de dissolução mostraram que das 17 diferentes marcas de medicamentos brasileiros e 17 diferentes produtos da Nigéria, 94,12% e 58,82% foram aprovados, respectivamente


Subject(s)
Solubility , Brazil/ethnology , Pharmaceutical Preparations/analysis , Africa/ethnology , Dissolution , United States Food and Drug Administration , Albendazole/pharmacology , Ibuprofen , Carvedilol/pharmacology , Furosemide/pharmacology , Methods , Acetates/adverse effects
5.
Braz. J. Pharm. Sci. (Online) ; 58: e19731, 2022. tab, graf
Article in English | LILACS | ID: biblio-1394038

ABSTRACT

Abstract Poorly water-soluble drugs, such as the antifungal drug griseofulvin (GF), exhibit limited bioavailability, despite their high membrane permeability. Several technological approaches have been proposed to enhance the water solubility and bioavailability of GF, including micellar solubilization. Poloxamers are amphiphilic block copolymers that increase drug solubility by forming micelles and supra-micellar structures via molecular self-association. In this regard, the aim of this study was to evaluate the water solubility increment of GF by poloxamer 407 (P407) and its effect on the antifungal activity against three Trichophyton mentagrophytes and two T. rubrum isolates. The GF water solubility profile with P407 revealed a non-linear behavior, well-fitted by the sigmoid model of Morgan-Mercer-Flodin. The polymer promoted an 8-fold increase in GF water solubility. Fourier-transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), and 2D nuclear magnetic resonance (NMR Roesy) spectroscopy suggested a GF-P407 interaction, which occurs in the GF cyclohexene ring. These results were supported by an increase in the water solubility of the GF impurities with the same molecular structure. The MIC values recorded for GF ranged from 0.0028 to 0.0172 mM, except for T. Mentagrophytes TME34. Notably, the micellar solubilization of GF did not increase its antifungal activity, which could be related to the high binding constant between GF and P407.


Subject(s)
Solubility , Spectrum Analysis/methods , Trichophyton/classification , Poloxamer/analogs & derivatives , Griseofulvin/agonists , Pharmaceutical Preparations/administration & dosage , Biological Availability , Magnetic Resonance Spectroscopy/methods , Molecular Structure , Antifungal Agents/administration & dosage
6.
Braz. J. Pharm. Sci. (Online) ; 58: e20013, 2022. tab, graf
Article in English | LILACS | ID: biblio-1394062

ABSTRACT

The aim of the present study is to improve the solubility and antimicrobial activity of 3-(3-(2-chlorophenyl)prop-2-enoyl)-4-hydroxycoumarin by formulating its inclusion complexes with 2-hydroxypropyl-ß-cyclodextrin in solution and in solid state. The phase solubility study was used to investigate the interactions between 3-(3-(2-chlorophenyl)prop-2-enoyl)-4-hydroxycoumarin and 2-hydroxypropyl-ß-cyclodextrin and to estimate the molar ratio between them. The structural characterization of binary systems (prepared by physical mixing, kneading and solvent evaporation methods) was analysed using the FTIR-ATM spectroscopy. The antimicrobial activity of 3-(3-(2-chlorophenyl)prop-2-enoyl)-4-hydroxycoumarin and inclusion complexes prepared by solvent evaporation method was tested by the diffusion and dilution methods on various strains of microorganisms. The results of phase solubility studies showed that 3-(3-(2-chlorophenyl)prop-2-enoyl)-4-hydroxycoumarin formed the inclusion complexes with 2-hydroxypropyl-ß-cyclodextrin of AP type. The solubility of 3-(3-(2-chlorophenyl)prop-2-enoyl)-4-hydroxycoumarin was increased 64.05-fold with 50% w/w of 2-hydroxypropyl-ß-cyclodextrin at 37 oC. The inclusion complexes in solid state, prepared by the solvent evaporation method, showed higher solubility in purified water and in phosphate buffer solutions in comparison with 3-(3-(2-chlorophenyl)prop-2-enoyl)-4-hydroxycoumarin alone. The inclusion complexes prepared by solvent evaporation method showed higher activity on Bacillus subtilis and Staphylococcus aureus compared to uncomplexed 3-(3-(2-chlorophenyl)prop-2-enoyl)-4-hydroxycoumarin due to improved aqueous solubility, thus increasing the amount of available 3-(3-(2-chlorophenyl)prop-2-enoyl)-4-hydroxycoumarin that crosses the bacterial membrane.


Subject(s)
Solubility , Cyclodextrins/agonists , Anti-Infective Agents , Spectrum Analysis/instrumentation , Staphylococcus aureus/classification , Bacillus subtilis/classification , Spectroscopy, Fourier Transform Infrared , Dilution
7.
Braz. dent. sci ; 25(2): 1-8, 2022. tab, ilus
Article in English | LILACS, BBO | ID: biblio-1370587

ABSTRACT

Objective: Resin-modified glass ionomer (RMGI) cements are among the commonly used restorative materials in low stress-bearing areas and also for temporary restorations. The competition between acid-base reactions and light polymerization reactions in delayed curing of RMGIs can affect their physical and mechanical properties, as well as their degree of conversion. Since solubility, color stability, and opacity are among the main physical properties affecting the durability and clinical service of RMGI restorations, this study aimed to assess the effect of delayed curing on solubility, color stability, and opacity of Fuji II LC RMGI. Material and Methods: This in vitro, experimental study evaluated 80 Fuji II LC RMGI specimens (10 specimens per each in 4 groups) in terms of solubility, color stability, and opacity at 6 months later. Specimens were cured immediately or were cured with 1, 5 and 10 min delay. Results: Maximum solubility and minimum change in opacity and color stability at 6 months were noted in the group with delayed curing by 10 min. A significant difference was noted in the solubility of specimens cured after 10 min and 1 min. Significant differences were also noted in the opacity and color stability of specimens cured after 10 min and all other groups (P < 0.05). Conclusion: Delayed curing by 1 min decreased the solubility of RMGI specimens compared with immediate curing or curing after 5 min. Although this difference did not reach statistical significance. Color stability and changes in opacity are mainly influenced by the acid-base reactions rather than polymerization reactions.(AU)


Objetivo: Cimentos de ionômero de vidro modificado por resina (CIVMR) estão entre os materiais restauradores mais comumente utilizados em áreas de baixa tensão e também para restaurações temporárias. A competição entre reações ácido-base e reações provenientes da fotopolimerização tardia dos CIVRMs podem afetar suas propriedades físicas e mecânicas, bem como seu grau de conversão. Uma vez que a solubilidade, estabilidade de cor e opacidade estão entre as principais propriedades físicas que afetam a durabilidade e o tempo de serviço clinico de restaurações de CIVMR, este estudo teve como objetivo avaliar o efeito da fotopolimerizaçao tardia na solubilidade, estabilidade de cor e opacidade do CIVMR Fuji II LC. Material e Métodos: Este estudo experimental in vitro avaliou 80 espécimes de CIVMR Fuji II LC (4 grupos com 10 espécimes cada) em termos de solubilidade, estabilidade de cor e opacidade apos 6 meses. As amostras foram fotopolimerizadas imediatamente ou com 1, 5 e 10 min de atraso. Resultados: Máxima solubilidade e mínima alteração na opacidade e estabilidade da cor em 6 meses foram observadas no grupo com fotopolimerização tardia em 10 min. Uma diferença significativa foi observada na solubilidade das amostras fotopolimerizadas após 10 min e 1 min. Diferenças significativas também foram observadas na opacidade e estabilidade de cor das amostras fotopolimerizadas após 10 min e em todos os outros grupos (P <0,05). Conclusão: A fotopolimerizaçao tardia em 1 min diminuiu a solubilidade das amostras CIVMR em comparação com a fotopolimerizaçao imediata ou após 5 min. Embora essa diferença não tenha alcançado significância estatística. A estabilidade da cor e as mudanças na opacidade são influenciadas principalmente por reações ácido-base, em vez de reações causadas pela polimerização(AU)


Subject(s)
Solubility , Color , Glass Ionomer Cements
8.
Braz. J. Pharm. Sci. (Online) ; 58: e18553, 2022. tab, graf
Article in English | LILACS | ID: biblio-1360166

ABSTRACT

Abstract The aqueous solubility of cefixime trihydrate (a water insoluble drug) using different hydrotropic agents was determined and solid dispersions of cefixime trihydrate were prepared by hydrotropic solubilization technique. The drugs content were determined. The aqueous solubility of v was increased many fold in presence of sodium acetate trihydrate as hydrotropic agent. This hydrotropic agent was used to prepare solid dispersion of cefixime trihydrate. Cefixime trihydrate and sodium acetate trihydrate were accurately weighed and taken in a 200 mL beaker. Distilled water 10-15 mL was taken to dissolve hydrotropic agent using heat (48-50 °C). The drug was then added to it and magnetically stirred till whole mass get viscous. The solid dispersions of cefixime trihydrate were characterized by XRD, DSC and IR studies. DSC thermogram, XRD and Infra-Red spectra were studied. Solid dispersions, thus prepared, showed faster release of the drug as compared to pure drug and physical mixture.


Subject(s)
Solubility/drug effects , Pharmaceutical Preparations/analysis , Methods , Water , Sodium Acetate/administration & dosage , Cefixime/adverse effects
9.
Braz. dent. sci ; 25(1): 1-8, 2022. tab, ilus
Article in English | LILACS, BBO | ID: biblio-1361498

ABSTRACT

Objective: To evaluate the influence of the incorporation of a polymerization catalyst to a light-cured pulp capping material on mechanical behavior and physicochemical characteristics. Material and Methods: Different percentages (2 wt%, and 4 wt%) of diphenyliodonium hexafluorophosphate (DPI) were incorporated into the Ultra-Blend Plus, a resin-modified calcium-based cement. The material without incorporation of DPI (0 wt%) served as control. Degree of Conversion (DC), Flexural Strength (FS), Elastic Modulus (EM), Water Sorption (WSp), Solubility (Sl), and pH of eluate at 24-h, 72-h, and 7-day storage times were measured. One-way ANOVA/Tukey posthoc tests were used to analyze the data (p <0.05). Results: For DC, FS, and EM, materials with different % of DPI showed statistically significant differences, so that 0% provided the lowest values and 2% the highest values. Materials with 0% and 2% of DPI provided statistically the lowest WSp, whilst material with 0% of DPI showed statistically the highest Sl. Conclusion: All materials provided statistically similar pH to eluates regardless of storage time, although only materials with DPI at 2% and 4% maintained pH of eluates statistically similar from 72 h to 7 days storage times.(AU)


Objetivo: avaliar a influência nas propriedades mecânicas e físico-químicas da incorporação de um catalisador de polimerização a um protetor pulpar fotoativável. Material e Métodos: foram adicionadas diferentes porcentagens em massa (2% e 4%) de hexafluorofosfato de difeniliodônio (DPI) ao Ultra-Blend Plus, um cimento à base de hidróxido de cálcio modificado por resina. O material sem a adição do DPI (0%) serviu como controle. Foram avaliados: Grau de Conversão (DC), Resistência Flexural (FS), Módulo de Elasticidade (EM), Sorção (WSp), Solubilidade (SI) e o pH do eluato nos tempos de 24h, 72h e 7 dias de armazenamento. ANOVA 1-way com pós-teste de Tukey (p <0.05). Foi utilizado para avaliar os resultados estatisticamente. Resultados: Os materiais com diferentes % de DPI apresentaram diferenças significativas para os testes de DC, FS e EM. A porcentagem em massa de 0% de DPI mostrou valores inferiores a todos os testados e os materiais com adição 2% apresentaram a melhor performance. Materiais com 0% e 2% de DPI apresentaram valores inferiores de WSp; a porcentagem de 0% proporcionou valores estatisticamente maiores para SI. Conclusão: Todos os materiais testados apresentaram pH semelhante nos eluatos independente do tempo de armazenamento, contudo, apenas os materiais com 2% e 4% mantiveram o pH dos eluatos estatisticamente similares nos tempos de estocagem de 72h a 7 dias.(AU)


Subject(s)
Dental Pulp Capping , Elastic Modulus , Polymerization , Solubility
10.
Article in Chinese | WPRIM | ID: wpr-927916

ABSTRACT

The present study explored the effect of co-amorphous technology in improving the dissolution rate and stability of silybin based on the puerarin-silybin co-amorphous system prepared by the spray-drying method. Solid-state characterization was carried out by powder X-ray diffraction(PXRD), polarizing microscopy(PLM), Fourier transform infrared spectroscopy(FT-IR), differential scanning calorimetry(DSC), etc. Saturated powder dissolution, intrinsic dissolution rate, moisture absorption, and stability were further investigated. The results showed that puerarin and silybin formed a co-amorphous system at a single glass transition temperature which was higher than that of any crude drug. The intrinsic dissolution rate and supersaturated powder dissolution of silybin in the co-amorphous system were higher than those of the crude drug and amorphous system. The co-amorphous system kept stable for as long as three months under the condition of 40 ℃, 75% relative humidity, which was longer than that of the single amorphous silybin. Therefore, the co-amorphous technology could significantly improve the dissolution and stability of silybin.


Subject(s)
Calorimetry, Differential Scanning , Desiccation , Drug Compounding/methods , Drug Stability , Silymarin , Solubility , Spectroscopy, Fourier Transform Infrared , Technology , X-Ray Diffraction
11.
Braz. J. Pharm. Sci. (Online) ; 58: e191123, 2022. tab, graf
Article in English | LILACS | ID: biblio-1394050

ABSTRACT

Chemotherapy induced nausea and vomiting (CINV) and post-operative nausea and vomiting (PONV) is a problem, often occurs in patient. Inspite of high bioavailability, the demerits such as: hepatic first pass metabolism and invasive nature of oral and parenteral dosage forms can be avoided with anti-emetic therapy of transdermal device. The major objective of the present study is to modify the hydrochloride (HCl) form of Ondansetron (OND) to the base form followed by improvement of solubility and permeability of OND by employing solid dispersion (SD) loaded patches. Preformulation study, as observed, begins with an approach to enthuse solubility of OND by SD technique choosing different carriers. The choice of carriers was rationalized by phase solubility study. Several combinations of transdermal films were prepared with pure drug, carriers and SDs with plasticizer Ka values of OND-HPßCD binary system were found lower (54.43 to 187.57 M-1) than that of OND-PVP K-30 binary system (1156.77 to 12203.6 M-1). The drug content of SDs and patches were found satisfactory. Better permeation rate (236.48±3.66 µg/3.935 cm2) with promising flux enhancement (8.30 fold) was found with DBP loaded SD patch (P6*). Hence, enhancement of solubility and permeability of P6* ensures that it can successfully enhance the bioavailability


Subject(s)
Plasticizers/adverse effects , Solubility , Ondansetron/antagonists & inhibitors , Patients/classification , Vomiting , Pharmaceutical Preparations/analysis , Postoperative Nausea and Vomiting , Dosage Forms , Drug Therapy/instrumentation , Methods , Motion Pictures/classification
12.
Braz. J. Pharm. Sci. (Online) ; 58: e18800, 2022. tab, graf, ilus
Article in English | LILACS | ID: biblio-1364431

ABSTRACT

Abstract Efavirenz is one of the most commonly used drugs in HIV therapy. However the low water solubility tends to result in low bioavailability. Drug nanocrystals, should enhance the dissolution and consequently bioavailability. The aim of the present study was to obtain EFV nanocrystals prepared by an antisolvent technique and to further observe possible effect, on the resulting material, due to altering crystallization parameters. A solution containing EFV and a suitable solvent was added to an aqueous solution of particle stabilizers, under high shear agitation. Experimental conditions such as solvent/antisolvent ratio; drug load; solvent supersaturation; change of stabilizer; addition of milling step and solvents of different polarities were evaluated. Suspensions were characterized by particle size and zeta potential. After freeze- dried and the resulting powder was characterized by PXRD, infrared spectroscopy and SEM. Also dissolution profiles were obtained. Many alterations were not effective for enhancing EFV dissolution; some changes did not even produced nanosuspensions while other generated a different solid phase from the polymorph of raw material. Nevertheless reducing EFV load produced enhancement on dissolution profile. The most important modification was adding a milling step after precipitation. The resulting suspension was more uniform and the powder presented grater enhancement of dissolution efficacy.


Subject(s)
Efficacy/classification , HIV/pathogenicity , Crystallization/instrumentation , Dissolution/methods , Particle Size , Solubility , Pharmaceutical Preparations/administration & dosage , Excipients/pharmacology , Dissolution/classification , Nanoparticles/administration & dosage , Methods
13.
Dent. press endod ; 11(2)maio-ago.2021. Ilus
Article in English | LILACS | ID: biblio-1377855

ABSTRACT

Introdução: A solubilidade é uma propriedade relaciona- da à dissociação dos constituintes do material, pela ação do contato com o líquido circundante. Introdução: O objetivo do presente estudo foi avaliar o efeito da hidratação durante a varredura com microtomografia (micro-TC) sobre a alteração volumétrica do MTA HP. Métodos: foram utilizados 20 dentes incisivos superiores de acrílico com cavidade retrógrada. O cimento MTA HP foi inserido na cavidade com um condensador Paiva. As amostras foram inspecionadas visualmente com uma lupa de 5x, para garantir que não permanecessem espaços vazios ou lacunas. Os espécimes foram divididos em dois grupos (n=10). Os dentes foram escaneados logo após o manuseio do MTA. Para o grupo com imersão em água, Eppendorf hidratado foi mantido com 1mL de água durante a varredura; no outro grupo, os dentes foram escaneados sem água. Nos dois grupos, os dentes foram imersos em água durante sete dias. Em seguida, os dentes foram escaneados novamente em micro-TC usando os mesmos parâmetros e condições de cada grupo. Foi realizada a reconstrução das imagens pelo software Nrecon e o volume de solubilidade, determinado pelo software CTan, analisando-se a variação volumétrica. Resultados: O grupo de corpos de prova escaneados imersos na água apresentou maior variação volumétrica, com diferenças estatisticamente significativas em relação ao grupo escaneado sem imersão. O escaneamento do corpo de prova imerso em água favorece uma maior perda volumétrica do material. Conclusão: Os estudos para avaliar a variação volumétrica de cimentos de silicato de cálcio devem ser feitos com imersão em água.


Introduction: Solubility is a property related to the dissocia- tion of the constituents of the material by the action of contact with the surrounding liquid, for this reason, the aim of this study was to evaluate the effect of the hydration during the scanning in the microtomography on the volumetric alteration of the MTA HP. Methods: Twenty acrylic teeth upper incisor with retrograde cavity were utilized. The MTA HP cement was inserted into the cavity using a Paiva condensor. The specimens were visually inspected with a 5x magnifying glass to ensure they did not remain void or gaps. The specimens were divided into 2 groups (n=10). The teeth were scanned shortly after handling the MTA. For the group with water immersion, hydrated Eppendorf was kept with 1mL the water during the scanning and the other group, the teeth were scanning without water. In the two groups the teeth were immersed into water during 7 days. Next the teeth were newly scanned in the Micro-CT using the same parameters and conditions of each group. Reconstruction of images by the Nrecon software and the solubility volume determined by the CTan, analyzing the volumetric change. Results: The group of specimens scanned immersed into the water presented higher volumetric change with statistically significant differences in relation the group scanned without immersion. The scanning of the specimen immersed in water favors the greater volumetric loss of the material. Conclusion: Studies to evaluate volumetric change of calcium silicate cements should be made immersed in wate


Subject(s)
Pemetrexed , Immersion , Minerals , Solubility , Methods
14.
Electron. j. biotechnol ; 50: 1-9, Mar. 2021. ilus, tab, graf
Article in English | LILACS | ID: biblio-1292302

ABSTRACT

BACKGROUND: Phospholipase D (PLD) is used as the biocatalyst for phosphatidylserine (PS) production. In general, PLD was expressed in insoluble form in Escherichia coli. High-level soluble expression of PLD with high activity in E. coli is very important for industrial production of PLD. RESULTS: Streptomyces chromofuscus PLD coding gene was codon-optimized, cloned without signal peptide, and expressed in E. coli. The optimal recombinant E. coli pET-28a+PLD/BL21(DE3) was constructed with pET-28a without His-tag. The highest PLD activity reached 104.28 ± 2.67 U/mL in a 250-mL shake flask after systematical optimization. The highest PLD activity elevated to 122.94 ± 1.49 U/mL by feeding lactose and inducing at 20 C after scaling up to a 5.0-L fermenter. Substituting the mixed carbon source with 1.0 % (w/v) of cheap dextrin and adding a feeding medium could still attain a PLD activity of 105. 81 ± 2.72 U/mL in a 5.0-L fermenter. Fish peptone from the waste of fish processing and dextrin from the starch are both very cheap, which were found to benefit the soluble PLD expression. CONCLUSIONS: After combinatorial optimization, the high-level soluble expression of PLD was fulfilled in E. coli. The high PLD activity along with cheap medium obtained at the fermenter level can completely meet the requirements of industrial production of PLD.


Subject(s)
Phospholipases/metabolism , Streptomyces/enzymology , Solubility , Streptomyces/genetics , Temperature , Codon , Combinatorial Chemistry Techniques , Escherichia coli
15.
Article in English | LILACS, BBO | ID: biblio-1143399

ABSTRACT

ABSTRACT Objective: To evaluate the antibacterial effect and the solubility of experimental root canal filling pastes containing the phytoconstituents terpineol and cinnamaldehyde. Material and Methods: Minimum Inhibitory Concentration (MIC) of each phytoconstituent was determined against Enterococcus faecalis. Five groups of antibiotic pastes based on zinc oxide were obtained by mixing: only terpineol, only cinnamaldehyde, terpineol and cinnamaldehyde combined, chlorhexidine (antibiotic control), and CTZ paste (control paste). Antibacterial activity was analyzed through direct contact test within 24 and 72 hours. Solubility was evaluated by spectrophotometry within 48 and 144 hours. Antibacterial activity data were analyzed descriptively, and solubility data was analyzed using ANOVA and Tukey tests (p<0.05). Results: The MIC obtained for terpineol and cinnamaldehyde were, respectively, 2000 µg/mL and 500 µg/mL. After 24h, only the terpineol paste did not inhibit E. faecalis growth. After 72h, all groups inhibited E. faecalis growth. After 48h, the highest solubility was verified in the terpineol paste (p<0.05), and no differences were detected among other groups (p>0.05). After and 144h, highest solubility was observed in the terpineol paste (p<0.05), followed by the CTZ paste (p<0.05). No differences were detected for cinnamaldehyde, terpineol+cinnamaldehyde and chlorhexidine pastes (p>0.05). Conclusion: Pastes containing cinnamaldehyde or terpineol+cinnamaldehyde showed antibacterial activity against E. faecalis similar to CTZ paste, with lower solubility.


Subject(s)
Root Canal Obturation/instrumentation , Tooth, Deciduous , Plant Extracts , Enterococcus faecalis , Anti-Bacterial Agents , Solubility , Spectrophotometry , Brazil/epidemiology , Analysis of Variance , Statistics, Nonparametric
16.
Braz. J. Pharm. Sci. (Online) ; 57: e181083, 2021. tab
Article in English | LILACS | ID: biblio-1350228

ABSTRACT

Among the methods described for determining the solubility, shake-flask is suitable to evaluate the equilibrium solubility according to the BCS. Nevertheless, experimental conditions related to the shake-flask method are not well described. Evaluating the effects of experimental conditions on solubility measurements by shake-flask method is important and contributes in biowaiver decision. For this work, propranolol hydrochloride and nimesulide were used as model compound of high and low solubility, respectively. Equilibrium solubility was evaluated at 37 ºC, 100 rpm during 48 hours in buffer media. Effects of the rotation speed, temperature, substance in excess and aliquot withdrawn were evaluated. Small variations of temperature caused significant differences in the solubility and then this parameter must be controlled. Excess of raw material influenced the results of the nimesulide, then, little excess is recommended. Rotation speed did not cause differences in the equilibrium solubilities, but at 150 rpm the equilibrium was reached faster. Aliquot did not present significant differences, but excessive withdrawn should be avoided. Therefore, the evaluation of equilibrium solubility using shake-flask method must be performed in physiological pH conditions, 37 ± 1 ºC, substance in excess 10% above saturation, 50, 100 or 150 rpm and aliquot withdrawn not more than 10% of the media volume.


Subject(s)
Solubility , Batch Cell Culture Techniques/methods , Pharmaceutical Preparations/administration & dosage
17.
Braz. oral res. (Online) ; 35: e045, 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1153603

ABSTRACT

Abstract The objective of this study was to evaluate the biocompatibility and mechanical properties of two commercially available and one experimental periodontal dressing materials. The cytotoxicity of Periobond ® , Barricaid ® and one experimental periodontal dressing based on Exothane ® 8 monomer was tested on 3T3/NIH mouse fibroblast. Genotoxicity was assessed by micronuclei formation, and cell alterations were analyzed using light microscopy. Both biological assays were performed using the eluate obtained from specimens after 24, 72, or 168 hours of incubation. Mechanical characterization was assessed through the ultimate tensile strength and the water sorption and solubility tests. The significance level of α = 0.05 was used for all statistical analyses. All the materials promoted a cell viability lower than 60% in all evaluated times. In general, the cell viability was significantly reduced after 72 and 168h of specimens' incubation. Considering the factor material, there were not statistical differences in the cell viability (p = 0.156). The genotoxicity was not statistically significant among the groups in the different periods of time (p > 0.05). Differences in the ultimate tensile strength values were not statistically significant different among the groups (p = 0.125). Periobond ® showed the higher water sorption values (p < 0.001). Regarding solubility, there were no statistical differences between the groups (p = 0.098). All the periodontal dressing materials evaluated in this study exerted a cytotoxic effect against mouse fibroblasts, and their toxicity became more evident over time. Among the materials evaluated, the experimental light-cure type has shown overall similar properties to the commercial references.


Subject(s)
Animals , Mice , Periodontal Dressings , Bandages , Solubility , Tensile Strength , Materials Testing
18.
Braz. oral res. (Online) ; 35: e018, 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1142617

ABSTRACT

Abstract This study determined the effect of thiourethane-functionalized fillers (TU) on the antimicrobial properties, cytotoxicity, degree of conversion (DC), water sorption (Wsp) and solubility (Wsl) of experimental composites. TU-modified fillers were added at different ratios in experimental composites: 0 (Control-TU0), 25% (TU25), 50% (TU50), 75% (TU75) and 100wt% (TU100). The antimicrobial properties were detected through the exhaustion test and counting of Streptococus mutans colonies for biofilm formation. Cytotoxicity to human gingival fibroblasts was evaluated in three different parameters: XTT (2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide), NRU (Neutral Red Uptake assay) and CVDE (Crystal Violet Dye Exclusion test)) at the same cells. ELISA was used to measure the IL-6 and b-FGF biomarkers. DC was determined by Fourier-transformed infrared spectroscopy, while Wsp and Wsl by mass variations. Inhibitory capacity of biofilm formation was not observed for any material. All groups presented at least 70% of cell survival within the observed periods (24h and 7 days). Positive control (toxic) had high IL-6 values and low b-FGF values. No significant variations in DC, Wsp, and Wsl were observed among the experimental groups. The use of thiourethane did not present antimicrobial and cytotoxic activity and the tested materials presented equivalent properties to those conventionally used in dentistry.


Subject(s)
Humans , Water , Composite Resins/toxicity , Solubility , Materials Testing
19.
Braz. J. Pharm. Sci. (Online) ; 57: e18910, 2021. tab, graf
Article in English | LILACS | ID: biblio-1345454

ABSTRACT

Chemotherapy induced nausea and vomiting (CINV) is an issue, which usually occurs in cancer patient. Despite high bioavailability of oral and intravenous administration, these have some drawbacks. The oral route causes hepatic first pass metabolism and intravenous route is invasive in nature. Hence, antiemetic drug by means of transdermal route is necessary to administer in such cases. The aim of the present investigation is to develop suitable Transdermal Therapeutic System (TTS) with an objective to enhance solubility and skin permeability properties of metoclopramide base. Preformulation study begins with an approach to enhance solubility of 40 metoclopramide base by solid dispersion technique. transdermal films were prepared with 41 the solid dispersion as well as with pure drug. Phase solubility study at various temperatures reveals binding constants (Ka, 95-350 M-1 for PVP K30; 56-81 M-1 for HPßCD). Spontaneity of solubilization was justified by AL type linear profiles. The films showed satisfactory diffusion (%), permeation rate and flux after 8 h study. The transdermal patches as prepared were analyzed under FTIR, DSC and SEM. Both solubility and permeability rate in this investigation have been enhanced. So, it can be affirmed that this route would effectively enhance bioavailability


Subject(s)
Solubility , Metoclopramide/antagonists & inhibitors , Patients/classification , Pharmaceutical Preparations/administration & dosage , Biological Availability , Spectroscopy, Fourier Transform Infrared , Diffusion/drug effects , Drug Therapy , Administration, Intravenous/instrumentation , Motion Pictures , Neoplasms/pathology
20.
Article in Chinese | WPRIM | ID: wpr-879012

ABSTRACT

To evaluate the effects of Hydroxypropyl methylcellulose acetate succinate(HPMCAS MF) on absorption of silybin(SLB) from supersaturable self-nanoemulsifying drug delivery system which was pre-prepared at the early stage experiment. The cell toxicity of self-emulsifying preparation was evaluated by the MTT method, and the in vitro membrane permeability and absorption promoting effect of the self-emulsifying preparation were evaluated by establishing a Caco-2 cell monolayer model. The in vivo and in vitro supersaturation correlation was evaluated via the blood concentration of SLB. The results of MTT showed that the concentration of the preparation below 2 mg·mL~(-1)(C_(SLB) 100 μg·mL~(-1)) was not toxic to Caco-2 cells, and the addition of polymer had no significant effect on Caco-2 cells viability. As compared with the solution group, the transport results showed that the P_(app)(AP→BL) of the self-emulsifying preparation had a very significant increase; the transport rate of silybin can be reduced by polymer in 0-30 min; however, there was no difference in supersaturated transport between supersaturated SLB self-nanoemulsion drug delivery system(SLB-SSNEDDS) and SLB self-nanoemulsion drug delivery system(SLB-SNEDDS) within 2 hours. As compared with SLB suspension, pharmacokinetic parameters showed that the blood concentration of both SLB-SNEDDS and SLB-SSNEDDS groups were significantly increased, and C_(max) was 5.25 times and 9.69 times respectively of that in SLB suspension group, with a relative bioavailability of 578.45% and 1 139.44% respectively. C_(max) and relative bioavailability of SLB-SSNEDDS were 1.85 times and 197% of those of SLB-SNEDDS, respectively. Therefore, on the one hand, SSNEDDS can increase the solubility of SLB in gastrointestinal tract by maintaining stability of SLB supersaturation state; on the other hand, the osmotic transport process of SLB was regulated through the composition of its preparations, and both of them could jointly promote the transport and absorption of SLB to improve the oral bioavailability of SLB.


Subject(s)
Administration, Oral , Biological Availability , Caco-2 Cells , Drug Delivery Systems , Emulsions , Humans , Methylcellulose/analogs & derivatives , Nanoparticles , Particle Size , Silymarin , Solubility
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