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1.
Braz. J. Pharm. Sci. (Online) ; 59: e20493, 2023. tab, graf
Article in English | LILACS | ID: biblio-1439545

ABSTRACT

Abstract Hedera nepalensis (H. nepalensis) , belonging to the family Araliaceae, is a medicinal plant traditionally used to treat stomach problems. The current study investigated the gastroprotective potential and the mechanism of action of H. nepalensis in diclofenac-and ethanol-induced ulcer models. Anti-oxidant and lipid peroxidation inhibitory prospects of H. nepalensis were checked out by free radical scavenging assay and UV spectrophotometer respectively. Effect of H. nepalensis on the pH, gastric total acidity of gastric juice and protective effects of H. nepalensis against ulcer models have been examined. Histopathological studies have been carried out. The aqueous methanol extract of H. nepalensis (100 µg/mL) showed anti-oxidant (83.55%) and lipid peroxidation inhibitory (70.88%) potential at 1000 µg/mL; the extract had no buffer potential. The extract (400 mg/kg) significantly (81.12% and 63.46%) showed gastroprotective effect in diclofenac and ethanol-induced rat ulcer models respectively. Histopathological studies confirmed the biochemical findings. FTIR analysis showed the presence of carboxylic acid, alkanes, conjugated alkanes, aldehydes and alkyl-aryl ethers. Gallic acid, M-coumaric acid and quercetin were found by HPLC analysis. H. nepalensis exhibited significant protection against diclofenac and ethanol induced gastric damage by anti-oxidant and lipid peroxidation suppression effects suggesting potential broad utility in treatment of diseases characterized with gastric damage.


Subject(s)
Plants, Medicinal , Stomach/abnormalities , Stomach Ulcer/pathology , Araliaceae/classification , Hedera/classification , Ulcer/chemically induced , Diclofenac/agonists , Chromatography, High Pressure Liquid/methods , Spectroscopy, Fourier Transform Infrared/methods , Antioxidants
2.
Braz. J. Pharm. Sci. (Online) ; 59: e21114, 2023. tab, graf
Article in English | LILACS | ID: biblio-1429958

ABSTRACT

Abstract In this study, orodispersible films formed from hydroxypropyl methylcellulose (HPMC) E6 (2, 2.5, and 3%) and plasticizers ((glycerin (Gly), propylene glycol (PP), or polyethylene glycol (PEG)), containing doxazosin mesylate, were prepared by the solvent casting method and characterized. Design of experiments (DoE) was used as a statistical tool to facilitate the interpretation of the experimental data and allow the identification of optimal levels of factors for maximum formulation performance. Differential scanning calorimetry (DSC) curves and X-ray powder diffraction (XRPD) diffractograms showed doxazosin mesylate amorphization, probably due to complexation with the polymer (HPMC E6), and the glass transition temperature of the polymer was reduced by adding a plasticizer. Fourier transformed infrared (FTIR) spectroscopy results showed that the chemical structure of doxazosin mesylate was preserved when introduced into the polymer matrix, and the plasticizers, glycerin and PEG, affected the polymer matrix with high intensity. The addition of plasticizers increased the elongation at break and adhesiveness (Gly > PEG > PP), confirming the greater plasticizer effect of Gly observed in DSC and FTIR studies. Greater transparency was observed for the orodispersible films prepared using PP. The addition of citric acid as a pH modifier was fundamental for the release of doxazosin mesylate, and the desirability formulation had a release profile similar to that of the reference product


Subject(s)
Mechanical Tests/instrumentation , Motion Pictures/classification , Plasticizers/classification , Spectrum Analysis/methods , Calorimetry, Differential Scanning/instrumentation , Adhesiveness , Doxazosin/adverse effects , Spectroscopy, Fourier Transform Infrared/methods , Hypromellose Derivatives/adverse effects
3.
Braz. J. Pharm. Sci. (Online) ; 59: e211019, 2023. tab, graf
Article in English | LILACS | ID: biblio-1439505

ABSTRACT

Abstract The form of drug administration affects the success of treatment, since it can influence adherence of the patient to the therapy. The use of orodispersible films has emerged as a way to overcome some drawbacks of conventional methods of drug delivery, especially for patients experiencing difficulty in swallowing. These films are prepared using a matrix that incorporates the drug and contains other substances that confer the properties of the system. The present work describes the use of thermoplastic starch as a carrier for the model drug diclofenac, including film preparation and testing of its orodispersible potential. Preparation of the film employed a microwave oven to gelatinize and plasticize corn starch, with incorporation of the model drug, followed by solvent-casting. The samples were characterized using mechanical tests, analyses of water uptake and water content, and Fourier transform infrared spectroscopy. The results indicated that the film presented promising properties as an alternative system for oral drug administration, with good incorporation and distribution of the drug in the matrix. The material displayed satisfactory mechanical properties, which are crucial for this type of material, due to the need for oral administration and handling before use.


Subject(s)
Starch/agonists , Diclofenac/analysis , Pharmaceutical Preparations/administration & dosage , Spectroscopy, Fourier Transform Infrared/methods
4.
Braz. J. Pharm. Sci. (Online) ; 59: e22111, 2023. tab, graf
Article in English | LILACS | ID: biblio-1439497

ABSTRACT

Abstract Chagas disease is a neglected parasitic disease caused by Trypanosoma cruzi, whose treatment has remained unsatisfactory for over 50 years, given that it is limited to two drugs. Benznidazole (BZN) is an efficient antichagasic drug used as the first choice, although its poor water-solubility, irregular oral absorption, low efficacy in the chronic phase, and various associated adverse effects are limiting factors for treatment. Incorporating drugs with such characteristics into nanostructured lipid carriers (NLC) is a promising alternative to overcome these limiting obstacles, enhancing drug efficacy and bioavailability while reducing toxicity. Therefore, this study proposed NLC-BZN formulations in different compositions prepared by hot-melt homogenization followed by ultrasound, and the optimized formulation was characterized by FTIR, DRX, DSC, and thermogravimetry. Biological activities included in vitro membrane toxicity (red blood cells), fibroblast cell cytotoxicity, and trypanocidal activity against epimastigotes of the Colombian strain of T. cruzi. The optimized NLC-BZN had a small size (110 nm), negative zeta potential (-18.0 mV), and high encapsulation (1.64% of drug loading), as shown by infrared spectroscopy, X-ray diffraction, and thermal analysis. The NLC-BZN also promoted lower in vitro membrane toxicity (<3% hemolysis), and 50% cytotoxic concentration (CC50) for NLC-BZN in L929 fibroblast cells (110.7 µg/mL) was twice the value as the free BZN (51.3 µg/mL). Our findings showed that the NLC-BZN had higher trypanocidal activity than free BZN against the epimastigotes of the resistant Colombian strain, and this novel NLC-BZN formulation proved to be a promising tool in treating Chagas disease and considered suitable for oral and parenteral administration


Subject(s)
Trypanosoma cruzi/isolation & purification , X-Ray Diffraction/instrumentation , Chagas Disease/pathology , Neglected Diseases/classification , Parasitic Diseases/pathology , Spectrum Analysis/instrumentation , Sprains and Strains/classification , Thermogravimetry/methods , In Vitro Techniques/methods , Pharmaceutical Preparations/analysis , Spectroscopy, Fourier Transform Infrared/methods
5.
Braz. J. Pharm. Sci. (Online) ; 59: e22009, 2023. tab, graf
Article in English | LILACS | ID: biblio-1447565

ABSTRACT

Abstract Oxazolidine derivatives (OxD) have been described as third-line antibiotics and antitumoral agents. The inclusion complexes based on cyclodextrin could improve the solubility and bioavailability of these compounds. A novel synthetic OxD was used, and its inclusion complexes were based on 2-hydroxy-beta-cyclodextrin (2-HPßCD). We conducted an in silico study to evaluate the interaction capacity between OxD and 2-HPßCD. Characterization studies were performed through scanning electron microscopy (SEM), Fourier-transformed infrared (FTIR), nuclear magnetic resonance spectroscopy (1H-NMR), X-ray diffraction (XRD), and thermal analyses. A kinetic study of the OxD was performed, including a cytotoxicity assay using peripheral blood mononuclear cells (PBMCs). The maximum increment of solubility was obtained at 70 mM OxD using 400 mM 2-HPßCD. SEM analyses and FTIR spectra indicated the formation of inclusion complexes. 1H-NMR presented chemical shifts that indicated 1:1 stoichiometry. Different thermal behaviors were obtained. The pharmacokinetic profile showed a short release time. Pure OxD and its inclusion complex did not exhibit cytotoxicity in PBMCs. In silico studies provided a foremost insight into the interactions between OxD and 2-HPßCD, including a higher solubility in water and an average releasing profile without toxicity in normal cells


Subject(s)
Solubility/drug effects , Cyclodextrins/agonists , Microscopy, Electron, Scanning/methods , Magnetic Resonance Spectroscopy/methods , Spectroscopy, Fourier Transform Infrared/methods , Proton Magnetic Resonance Spectroscopy/methods , Anti-Bacterial Agents/analysis
6.
Braz. J. Pharm. Sci. (Online) ; 58: e20243, 2022. graf
Article in English | LILACS | ID: biblio-1403682

ABSTRACT

Abstract In drug therapy, it is important to provide therapeutic levels of drug to the site of action and maintain them during the treatment. This work describes the in vitro release of alendronate from sodium alginate cross-linked Montmorillonite (MMT) composite beads. Effect of crosslinking cation, concentration of montmorillonite and media on encapsulation efficiencies, and release profiles of alendronate were studied. Beads were characterized using equilibrium swelling ability study, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Energy-dispersive x-ray spectroscopy (EDX) and scanning electron microscopy (SEM). Results indicate that addition of montmorillonite increases the encapsulation efficiencies and slows down the release rates significantly.


Subject(s)
Bentonite/agonists , Alendronate/pharmacology , Alginates/pharmacology , X-Ray Diffraction/methods , In Vitro Techniques/methods , Pharmaceutical Preparations/analysis , Microscopy, Electron, Scanning/methods , Spectroscopy, Fourier Transform Infrared/methods
7.
Braz. J. Pharm. Sci. (Online) ; 58: e20180, 2022. tab, graf
Article in English | LILACS | ID: biblio-1403759

ABSTRACT

Abstract Conjunctivitis is an inflammation of the conjunctiva, which covers the white part of the eyeball. It can be caused by allergies, bacterial or viral infection. In situ hydrogels are three-dimensional hydrophilic cross-linked network of polymers. In situ hydrogel provided better therapeutic index when compared to conventional treatment. The present work describes the formulation and evaluation of ofloxacin and dexamethasone based on the concept of pH triggered in situ gelation. Carbopol 934p was used as the gelling agent in combination with HPMC, as a viscosity-enhancing agent, benzalkonium chloride as preservative, sodium chloride as tonicity adjusting agent. The prepared formulations were liquid at the low pH and underwent rapid transition into viscous gel at the pH of the tear fluid. Formulations were evaluated for various rheological, in vitro and in vivo release characteristics. Infrared spectroscopy studies showed that there were no interactions between the drug and polymers. Viscosity of the prepared hydrogels lies in the optimum range and drug was released up to 85 % as the end of 13 h. The prepared in situ hydrogel was sterile, non-irritant to the eye. The present study indicated that it is possible to develop safe and physiologically effective in situ hydrogel which is patient compliant.


Subject(s)
Animals , Rabbits , Dexamethasone/therapeutic use , Ofloxacin/therapeutic use , Conjunctivitis/drug therapy , Hydrogels/therapeutic use , Spectrum Analysis , Spectroscopy, Fourier Transform Infrared/methods
8.
Braz. J. Pharm. Sci. (Online) ; 58: e191009, 2022. tab, graf
Article in English | LILACS | ID: biblio-1394059

ABSTRACT

Nizatidine is an anti-secretogogue and a gastroprotective drug with a half-life of 1-2 h and is well absorbed in the stomach. This study aimed to optimize the process and develop floating microparticles of nizatidine that are based on low methoxyl pectin. Oil-in-oil dispersion method and Taguchi orthogonal array design were employed, and the prolonged residence time of the microparticles in the stomach was demonstrated. The constraints for independent variables, viz. A-polymer, B-internal solvent volume, C-surfactant, D-stirring rate and E-stirring time were set to generate the experimental runs. Particle size, percentage yield, micromeritic properties, entrapment efficiency, in vitro buoyancy and in vitro release were characterized. Surface morphology, zeta potential, in vitro release kinetics and in vivo floating performance of the optimized formulation was examined. The microparticles were free-flowing, irregular in shape and had a mean particle size distribution of 73-187 µ. Low methoxyl pectin played a predominant role in achieving buoyancy and optimum gastric retention for the modified release of the drug, suggesting Korsmeyer-Peppas model as the possible release mechanism. In vivo radiographic study in rabbits revealed that the drug was retained in the stomach for a period of 6 h. These results indicate that nizatidine floating microparticulate system provides modified drug release for the effective treatment of gastric ulcer


Subject(s)
Animals , Male , Female , Rabbits , Stomach/drug effects , Nizatidine/antagonists & inhibitors , Efficiency/classification , Solvents/adverse effects , Stomach Ulcer/pathology , In Vitro Techniques/instrumentation , Pharmaceutical Preparations/administration & dosage , Kinetics , Spectroscopy, Fourier Transform Infrared/methods , Drug Liberation
9.
Braz. J. Pharm. Sci. (Online) ; 58: e21034, 2022. tab, graf
Article in English | LILACS | ID: biblio-1420431

ABSTRACT

Abstract Despite decades of research, wound healing remains a significant public health problem. This study aimed to develop and evaluate a topical sodium alginate gel containing vancomycin (Van) loaded MMT NPs for wound healing applications. Van was loaded in MMT at different conditions (pHs of 6, 7 and temperatures of 40, 50 °C) (Van/MMT NPs). The optimum formulation (with the smallest particle size and a high value of zeta potential; 270.8 ± 77.35 nm and -35.96 ± 2.73, respectively) showed a high drug-loading capacity (entrapment efficacy of 96%) and a sustained release pattern of Van (95%) over 480 min. The optimum Van/MMT NPs were embedded into the sodium alginate (SA) gel (Van/MMT NPs/SA gel). The Van/ MMT NPs/SA gel showed a sustained and slow release pattern of Van (95%) over 50 h. FTIR tests revealed the electrostatic interaction between MMT and Van. The broth macrodilution tube method was used to determine the minimum inhibitory concentration (MIC) of Van, Van/ MMT NPs, and Van/MMT NPs/SA gel against Staphylococcus aureus. The results showed the promising antibacterial activity of Van/MMT NPs/SA gel, thus, this gel can be a promising formulation for the management of infected wounds


Subject(s)
Wound Healing/drug effects , Wound Infection/pathology , Bentonite/antagonists & inhibitors , In Vitro Techniques/methods , Vancomycin/agonists , Alginates/analysis , Wounds and Injuries/drug therapy , Pharmaceutical Preparations/administration & dosage , Spectroscopy, Fourier Transform Infrared/methods , Anti-Bacterial Agents/classification
10.
São Paulo; s.n; s.n; 2022. 80 p. tab, graf.
Thesis in Portuguese | LILACS | ID: biblio-1415544

ABSTRACT

O objetivo deste trabalho foi preparar e caracterizar nanocarreadores via auto-organização a partir da pectina de citros e lisozima para o encapsulamento da ß-lactose. Foram estudadas três condições de interação entre os biopolímeros variando a razão molar pectina/lisozima (3:1, 2:1, 1:1, 1:2 e 1:3), o pH e o tempo de aquecimento. A confirmação da interação foi determinada por espectroscopia no infravermelho por transformada de Fourier (FTIR) e por calorimetria de varredura diferencial (DSC). Os espectros de infravermelho evidenciaram que ligações de hidrogênio foram as principais forças envolvidas na formação dos nanocarreadores e sugeriram a ausência de ß-lactose livre na superfície das nanopartículas. Os termogramas evidenciaram que as nanopartículas formadas na presença de ß-lactose têm maior estabilidade térmica do que as nanopartículas sem ß-lactose. Para ambas as formulações estudadas, na presença e na ausência de ß-lactose, a formação das nanopartículas ocorreu entre os valores de pKa e ponto isoelétrico (pI) da pectina e lisozima, respectivamente, sendo a melhor razão de interação pectina/lisozima 1:2, em pH 10, a 80 ºC por 30 min. As nanopartículas foram formadas via auto-organização e todos as partículas apresentaram distribuição de tamanho homogênea, formato esférico, diâmetro inferior a 100 nm e carga superficial negativa. A morfologia e o tamanho das partículas pouco alteraram com a incorporação da -lactose. A eficiência de encapsulação (EE) da ß-lactose foi superior a 96% para as concentrações estudadas. Ensaios preliminares in vitro, em células epiteliais de câncer de cólon (HCT-116), evidenciaram que as nanopartículas formadas são capazes de adentrar no meio intracelular, possivelmente, por via endocitose


This work aimed to prepare and characterize nanocarriers via self-assembly using citrus pectin and lysozyme for ß-lactose encapsulation. Three interaction conditions between the biopolymers were studied, varying the pectin/lysozyme molar ratio (3:1, 2:1, 1:1, 1:2 and 1:3), pH and heating time. Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) determined the interaction's confirmation. The infrared spectra showed that hydrogen bonds were the main forces involved in the formation of nanocarriers and suggested the absence of free ß-lactose on the surface of the nanoparticles. The thermograms showed that nanoparticles formed in the presence of ß-lactose have greater thermal stability than nanoparticles without ß-lactose. For both formulations studied, in the presence and absence of lactose, the formation of nanoparticles occurred between the pKa and isoelectric point (pI) values of pectin and lysozyme, respectively, with the best pectin/lysozyme interaction molar ratio 1:2, at pH 10, at 80 °C for 30 min. Nanoparticles were formed via self-assembly, and all particles presented homogeneous size distribution, spherical shape, diameter less than 100 nm, and negative surface charge. The morphology and size of the particles changed little with the incorporation of ß-lactose. The encapsulation efficiency (EE) of ß-lactose was higher than 96% for the concentrations studied. Preliminary in vitro assays in colon cancer epithelial cells (HCT-116) showed that the nanoparticles formed are capable of entering the intracellular medium, possibly via endocytosis


Subject(s)
Muramidase/analysis , Pectins/analysis , Biopolymers/adverse effects , Calorimetry , Calorimetry, Differential Scanning/methods , Spectroscopy, Fourier Transform Infrared/methods , Colonic Neoplasms , Nanoparticles , Hydrogen-Ion Concentration , Lactose
11.
Braz. J. Pharm. Sci. (Online) ; 58: e19967, 2022. tab, graf
Article in English | LILACS | ID: biblio-1384000

ABSTRACT

Abstract Red lima bean (Phaseolus lunatus Linn) Family Fabaceae, has been modified by succinylation and annealing, and used as intra- and extra-granular disintegrants at concentrations of 5 and 10 %w/w in paracetamol tablet formulation in comparison with corn starch BP. The starches were characterised using FT-IR spectroscopy, SEM, proximate analysis, physicochemical and functional properties. FT-IR spectrometry revealed characteristic peaks at 1575.53 and 1713.99 cm-1 for the succinylated starch while the annealed showed no significant difference from the native starch. Modifications did not alter the ovoid shape of the native starch but reduced the particle size. Succinylation improved water absorption capacity, solubility and swelling of lima bean starch but annealing reduced the parameters. Tablets with disintegrants of lima bean starches generally had higher crushing strengths and lower friability than tablets with corn starch. Modifications reduced the disintegration time of the tablets when the starches were incorporated intra-granularly, which suggested particle-particle bond interruption and destruction of hydrogen bonds as mechanism of disintegration. Tablets containing 10 %w/w succinylated red lima bean starch incorporated intra-granularly had the highest disintegration efficiency ratio, DER, indicating a great balance between mechanical and disintegration properties. Modified red lima bean starches incorporated intra-granularly into paracetamol tablets led to faster disintegration and could efficiently substitute corn starch as disintegrant.


Subject(s)
Tablets/pharmacology , Abrus/classification , Starch and Fecula , Acetaminophen/classification , Spectrum Analysis/instrumentation , Spectroscopy, Fourier Transform Infrared/methods
12.
Braz. J. Pharm. Sci. (Online) ; 58: e19753, 2022. tab, graf
Article in English | LILACS | ID: biblio-1384012

ABSTRACT

Abstract The study is aimed to assess the compatibility of bilberry leaf powder extract (BLPE) with six excipients selected for sustained-release (SR) tablet formulation. The BLPE was obtained with the addition of L-arginine and Myo-inositol as the carriers. Thermogravimetric (TG-DTG) analysis and Fourier-transform infrared spectroscopy (FTIR), supported by Pearson correlation analysis, were applied to detect possible interactions in the binary mixtures (1:1) of the BLPE with each excipient. The TG-DTG showed some deviations in the thermal behavior of the BLPE / excipient mixtures. However, only the thermal behavior of magnesium stearate in the mixture significantly differed from individual samples, which suggested chemical interaction for this excipient. The FTIR analysis confirmed that the BLPE is compatible with Eudragit L100, Methocel K4M, Methocel K100LV, Avicel PH-101, and Plasdone S-630. Whereas it undergoes solid-state chemical interaction in the binary mixture with magnesium stearate. According to the FTIR-spectra, it is suggested that this interaction results in the formation of stearic acid and alkalization of the medium. These findings evidence for the possibility of using TG-DTG analysis as an independent thermal technique for compatibility studies and also confirm the earlier reported interaction of basic lubricants, e.g., stearic salts, with active ingredients containing amino groups.


Subject(s)
Behavior , Plant Extracts/analysis , Plant Leaves/classification , Vaccinium myrtillus/adverse effects , Vaccinium myrtillus/metabolism , Delayed-Action Preparations/analysis , Spectrum Analysis/instrumentation , Thermogravimetry/instrumentation , Spectroscopy, Fourier Transform Infrared/methods
13.
Braz. J. Pharm. Sci. (Online) ; 57: e18899, 2021. tab, graf
Article in English | LILACS | ID: biblio-1339302

ABSTRACT

Microbiological quality of pharmaceuticals is fundamental in ensuring efficacy and safety of medicines. Conventional methods for microbial identification in non-sterile drugs are widely used; however they can be time-consuming and laborious. The aim of this paper was to develop a chemometric-based rapid microbiological method (RMM) for identifying contaminants in pharmaceutical products using Fourier transform infrared with attenuated total reflectance spectrometry (FTIR-ATR). Principal components analysis (PCA) and linear discriminant analysis (LDA) were used to obtain a predictive model capable of distinguishing Bacillus subtilis (ATCC 6633), Candida albicans (ATCC 10231), Enterococcus faecium (ATCC 8459), Escherichia coli (ATCC 8739), Micrococcus luteus (ATCC 10240), Pseudomonas aeruginosa (ATCC 9027), Salmonella typhimurium (ATCC 14028), Staphylococcus aureus (ATCC 6538), and Staphylococcus epidermidis (ATCC 12228) microbial growth. FTIR-ATR spectra provide data on proteins, DNA/RNA, lipids, and carbohydrates constitution of microbial growth. Microbial identification provided by PCA/LDA based on FTIR-ATR method were compatible with those obtained using traditional microbiological methods. The chemometric-based FTIR-ATR method for rapid identification of microbial contaminants in pharmaceutical products was validated by assessing the sensitivity (93.5%), specificity (83.3%), and limit of detection (17-23 CFU/mL of sample). Therefore, we propose that FTIR-ATR spectroscopy may be used for rapid identification of microbial contaminants in pharmaceutical products and taking into account the samples studied


Subject(s)
Spectrum Analysis/instrumentation , Pharmaceutical Preparations/analysis , Discriminant Analysis , Spectroscopy, Fourier Transform Infrared/methods , Fourier Analysis , Pseudomonas aeruginosa/classification , Bacillus subtilis/classification , Candida albicans/classification , Limit of Detection
14.
Arq. bras. med. vet. zootec. (Online) ; 72(6): 2059-2068, Nov.-Dec. 2020. tab, graf
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1142288

ABSTRACT

O objetivo deste estudo foi investigar a interferência do teor de gordura do leite no ponto de congelamento (PC) obtido pelo infravermelho com transformada de Fourier (FTIR). Uma fração de leite cru foi desnatada, obtendo-se creme e leite desnatado. O leite integral e o desnatado foram adicionados com água (0%, 2%, 5%, 10%, 15% e 20%). O leite desnatado remanescente foi adicionado com creme (5%, 10%, 15%, 20%) e água (0%, 2%, 5%, 10%, 15% e 20%). As amostras foram analisadas para PC (crioscópio eletrônico e FTIR) e composição (FTIR). O PC medido por FTIR foi altamente correlacionado com o método do crioscópio eletrônico (acima de 98,5%) e, como esperado, a adição de água foi significativa (P≤0,001) ao aumentar o PC do leite em ambos os métodos. No entanto, o alto teor de gordura no leite cru resultou na redução do PC ao se utilizar o FTIR, enquanto o baixo teor de gordura resultou em aumento do PC (P≤0,001). Uma vez que a adição de água causou o efeito inverso do alto teor de gordura no PC medido por FTIR, é importante considerar o teor de gordura do leite para evitar interpretações erradas do PC quando se utiliza o método FTIR.(AU)


The objective of this study was to investigate the interference of milk fat content upon the Freezing Point (FP) obtained by Fourier-transform infrared (FTIR). A fraction of raw milk was skimmed, obtaining cream and skim milk. Whole and skim milk were added with water (0, 2, 5, 10, 15, and 20%). The remaining skim milk was added with cream (5, 10, 15, 20%) and water (0, 2, 5, 10, 15, and 20%). Samples were analyzed for FP (thermistor cryoscope and FTIR) and composition (FTIR). FP measured by FTIR was highly correlated with the thermistor cryoscope method (above 98.5%) and, as expected, water addition was significant (P≤0.001) upon increasing milk FP in both methods. However, high fat content in raw milk resulted in decreasing FP when using FTIR, while low fat content resulted in increased FP (P≤0.001). Since water addition caused the inverse effect of high fat on FP measured by FTIR, it is important to regard the fat content of milk to avoid misinterpretation of FP when using the FTIR method.(AU)


Subject(s)
Milk/chemistry , Food Storage/methods , Raw Foods/analysis , Frozen Foods/analysis , Spectroscopy, Fourier Transform Infrared/methods
15.
Braz. J. Pharm. Sci. (Online) ; 56: e18440, 2020. tab, graf
Article in English | LILACS | ID: biblio-1249159

ABSTRACT

In this study, naftifine (a topical antifungal drug) loaded poly(vinyl) alcohol (PVA)/sodium alginate (SA) nanofibrous mats were prepared using the single-needle electrospinning technique. The produced nanofibers were crosslinked with glutaraldehyde (GTA) vapor. The morphology and diameter of the electrospun nanofibers were studied by scanning electron microscopy (SEM). SEM images showed the smoothness of the nanofibers and indicated that the fiber diameter increased with crosslinking and drug loading. Atomic force microscopy (AFM) images confirmed the uniform production of the scaffolds, and elemental mapping via energy dispersive X-ray spectroscopy (EDS) showed the uniform distribution of the drug within the nanofibers. An attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy study demonstrated that naftifine has sufficient secondary interactions with the polymer blend. The crosslinking treatment decreased the burst drug release effectively and the release mechanism followed Korsmeyer-Peppas Super Case-II transport. Overall, these findings suggest the potential use of naftifine-loaded PVA/SA nanofibers as a topical antifungal drug delivery system.


Subject(s)
Administration, Topical , Nanofibers/analysis , Spectrometry, X-Ray Emission/instrumentation , Spectrum Analysis/instrumentation , Pharmaceutical Preparations/administration & dosage , Drug Delivery Systems , Spectroscopy, Fourier Transform Infrared/methods , Microscopy, Atomic Force/instrumentation , Alginates/adverse effects , Drug Liberation
16.
Braz. J. Pharm. Sci. (Online) ; 56: e17797, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132045

ABSTRACT

Oral fast-dispersible film was prepared by utlizing donepezil hydrochloride (drug) and various cellulose derivatives such as hydroxypropyl methyl cellulose (hypermellose) (HPMC), microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC) to treat Alzheimer's disease. NCC was synthesized by ultra-sonication method using MCC and this was converted to thinfilm formulation (NCC-F) using solvent casting technique. The interaction between the polymer and the drug was investigated by spectral analysis such as UV, FTIR, and 1H- NMR. FTIR confirmed that the compatibility of drug and polymer in ODF formulation. NCC-F has shown an average surface roughness of 77.04 nm from AFM and the average particle size of 300 nm from SEM analysis. Nano sized particle of NCC-F leads faster in vitro dissolution rate (94.53%) when compared with MCC-F and F3 formulation. Animal model (in vivo) studies of NCC-F formulation has reached peak plasma concentration (Cmax) up to 19.018 ng/mL in the span of (tmax) 4 h with greater relative bioavailability of 143.1%. These results suggested that high surface roughness with nanosized NCC-F formulation attained extended drug availability up to (t1/2) 70 h.


Subject(s)
Animals , Male , Female , Rats , In Vitro Techniques/methods , Dissolution/classification , Donepezil/agonists , Sonication/methods , Pharmaceutical Preparations/analysis , Cellulose , Spectroscopy, Fourier Transform Infrared/methods , Models, Animal , Alzheimer Disease/pathology
17.
Braz. J. Pharm. Sci. (Online) ; 56: e18484, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132064

ABSTRACT

Angiogenesis is the formation of new blood vessels from preexisting vasculature. Uncontrolled angiogenesis is associated with progression of several ocular pathologies, such as diabetic retinopathy and macular degeneration. Thus, the inhibition of this process consists in an interesting therapeutic target. Corosolic acid (CA) is a natural derivative of ursolic acid, found in many medicinal herbs and exhibits numerous biological properties, including the antiangiogenic activity. The present study reports the production of CA-loaded poly d,l-lactidecoglycolide acid (PLGA) devices by melt technique. HPLC-UV method was developed and validated to evaluate the uniformity and the release profile of the developed systems. The devices were also characterized by Fourier transform infrared spectroscopy, thermal analysis, and scanning electron morphology. It was studied the antiangiogenic activity of the CA-polymer system, using an in vivo model, the chorioallantoic membrane assay (CAM). CA was dispersed uniformly in the polymer matrix and no chemical interaction between the components of the formulation was verified. The implants presented a sustained release of the drug, which was confirmed by the morphological study and demonstrated an antiangiogenic activity. Therefore, the developed delivery system is a promising therapeutic tool for the treatment of ocular diseases associated with neovascularization or others related to the angiogenic process.


Subject(s)
Chorioallantoic Membrane/abnormalities , Macular Degeneration/pathology , Neovascularization, Pathologic/pathology , Polymers , Ultraviolet Rays/classification , Pharmaceutical Preparations/analysis , Chromatography, High Pressure Liquid/methods , Spectroscopy, Fourier Transform Infrared/methods , Diabetic Retinopathy
18.
Braz. J. Pharm. Sci. (Online) ; 56: e18575, 2020. tab, graf
Article in English | LILACS | ID: biblio-1285517

ABSTRACT

Buccal route of administration has many advantages such as improving patient compliance, bypassing the GIT and hepatic first pass effect. The objectives are to formulate mucoadhesive buccal tablet using Mefenamic acid and compatible excipients, and to evaluate the product using quality control tests and in vitro tests. The ingredients were subjected to Differential Scanning Calorimetry and Fourier Transform Infrared Spectroscopy studies for compatibility test and the results showed no interaction. Two batches of mefenamic buccal tablet were prepared. The tablet thickness and diameter are 3.75 mm and 12 mm respectively. All tablets are within the specification of +/- 5%. The in-house tablet hardness is 6.8-15kg and percent friabilation is not more than 0.8%. The disintegration test showed that all tablets disintegrated within 4 hours. The content uniformity showed that tablets are within the range of 85%-115%. The tablet weight is within the 5% range. The percent swelling is 53.83% to 58.86% and moisture absorption is 14.79% to 15.56%. The surface pH of the tablet is close to the salivary pH, which means that it would not irritate the buccal mucosa. The buccal tablet has a mucoadhesiveness of 0.196 to 0.200. There was no change in pH and size after subjecting it to stability studies in human saliva. Drug release studies showed 80.7% to 83.4% after 3 hours. Even after 3 months of subjecting the tablets to 40 ºC and 75% RH, results are within acceptable range. The results show the potential of the formulation as a mucoadhesive buccal tablet.


Subject(s)
Mefenamic Acid/analysis , Mouthwashes/analysis , Quality Control , Tablets/pharmacology , Calorimetry, Differential Scanning/methods , Spectroscopy, Fourier Transform Infrared/methods
19.
J. oral res. (Impresa) ; 8(supl.1): 19-23, ago. 9, 2019. ilus
Article in English | LILACS | ID: biblio-1141501

ABSTRACT

Objectives: The aim of this study was to evaluate chemical and topographical changes in the intaglio zirconia surface induced by chemical conditioning solutions using FTIR and SEM analysis. Material and method: twelve plates for each FTIR and SEM tests from each zirconia materials (UPCERA HT White, BruxZir® Solid Zirconia, and Copran® Multilayer), milled by a Yenadent CAD/CAM system, sintered and divided randomly into a three groups. A different surface conditioning was applied to the intaglio surface of each group: 30% hydrogen peroxide, 30% citric acid and control group. Result and discussion: by using of the FTIR spectroscopy, an evidence of new bands formation appeared at 1637cm-1 and 3352cm-1 due to the high oxidizing effect of hydrogen peroxide, and at 630cm-1 and 1663cm-1 due to the chelating action of citric acid, and simultaneously, SEM assessment of the surface topography took place, to identify lines, scratches, or surface dissociation that appeared on the intaglio zirconia surface after conditioning. Conclusion: such analysis provides an enhancement of new convenient, less expensive, reliable trials to improve micro-bond strength of luting cement to Y-TZP ceramics.


Subject(s)
Humans , Resins, Synthetic , Zirconium/analysis , Spectroscopy, Fourier Transform Infrared/methods , Microscopy, Electron, Scanning , Dental Cements , Hydrogen Peroxide
20.
Hig. aliment ; 33(288/289): 3117-3121, abr.-maio 2019. tab, graf
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1482525

ABSTRACT

Objetivou-se detectar diferenças espectrais entre leites de búfala, vaca e com misturas entre as espécies. Foram elaboradas formulações com leite de búfala, vaca e com inclusões crescentes de leite bovino ao bubalino. As amostras foram avaliadas em relação à composição química e características físico-químicas, além da obtenção de espectros por meio de Espectroscopia no Infravermelho com Transformada de Fourier. Verificou-se que amostras com maiores concentrações de leite bubalino apresentaram os maiores teores de gordura, proteínas, lactose, sólidos totais e sólidos desengordurados. Foram identificados 13 picos de absorção referentes aos compostos orgânicos do leite. Os tratamentos com maiores percentuais de leite de vaca apresentaram picos com intensidades inferiores em comparação aos tratamentos com maiores percentuais de leite de búfala.


Subject(s)
Food Contamination/analysis , Spectroscopy, Fourier Transform Infrared/methods , Spectroscopy, Fourier Transform Infrared/veterinary , Milk/chemistry , Cattle , Buffaloes
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