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1.
AAPS PharmSciTech ; 25(6): 154, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961012

RESUMO

Berberine is used in the treatment of metabolic syndrome and its low solubility and very poor oral bioavailability of berberine was one of the primary hurdles for its market approval. This study aimed to improve the solubility and bioavailability of berberine by preparing pellet formulations containing drug-excipient complex (obtained by solid dispersion). Berberine-excipient solid dispersion complexes were obtained with different ratios by the solvent evaporation method. The maximum saturation solubility test was performed as a key factor for choosing the optimal complex for the drug-excipient. The properties of these complexes were investigated by FTIR, DSC, XRD and dissolution tests. The obtained pellets were evaluated and compared in terms of pelletization efficiency, particle size, mechanical strength, sphericity and drug release profile in simulated media of gastric and intestine. Solid-state analysis showed complex formation between the drug and excipients used in solid dispersion. The optimal berberine-phospholipid complex showed a 2-fold increase and the optimal berberine-gelucire and berberine-citric acid complexes showed more than a 3-fold increase in the solubility of berberine compared to pure berberine powder. The evaluation of pellets from each of the optimal complexes showed that the rate and amount of drug released from all pellet formulations in the simulated gastric medium were significantly lower than in the intestine medium. The results of this study showed that the use of berberine-citric acid or berberine-gelucire complex could be considered a promising technique to increase the saturation solubility and improve the release characteristics of berberine from the pellet formulation.


Assuntos
Berberina , Química Farmacêutica , Composição de Medicamentos , Liberação Controlada de Fármacos , Excipientes , Tamanho da Partícula , Solubilidade , Berberina/química , Berberina/administração & dosagem , Berberina/farmacocinética , Excipientes/química , Composição de Medicamentos/métodos , Química Farmacêutica/métodos , Disponibilidade Biológica , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Pós/química , Difração de Raios X/métodos , Varredura Diferencial de Calorimetria/métodos
2.
Mol Pharm ; 21(7): 3471-3484, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38872243

RESUMO

Oligonucleotides are short nucleic acids that serve as one of the most promising classes of drug modality. However, attempts to establish a physicochemical evaluation platform of oligonucleotides for acquiring a comprehensive view of their properties have been limited. As the chemical stability and the efficacy as well as the solution properties at a high concentration should be related to their higher-order structure and intra-/intermolecular interactions, their detailed understanding enables effective formulation development. Here, the higher-order structure and the thermodynamic stability of the thrombin-binding aptamer (TBA) and four modified TBAs, which have similar sequences but were expected to have different higher-order structures, were evaluated using ultraviolet spectroscopy (UV), circular dichroism (CD), differential scanning calorimetry (DSC), and nuclear magnetic resonance (NMR). Then, the relationship between the higher-order structure and the solution properties including solubility, viscosity, and stability was investigated. The impact of the higher-order structure on the antithrombin activity was also confirmed. The higher-order structure and intra-/intermolecular interactions of the oligonucleotides were affected by types of buffers because of different potassium concentrations, which are crucial for the formation of the G-quadruplex structure. Consequently, solution properties, such as solubility and viscosity, chemical stability, and antithrombin activity, were also influenced. Each instrumental analysis had a complemental role in investigating the higher-order structure of TBA and modified TBAs. The utility of each physicochemical characterization method during the preclinical developmental stages is also discussed.


Assuntos
Aptâmeros de Nucleotídeos , Dicroísmo Circular , Oligonucleotídeos , Aptâmeros de Nucleotídeos/química , Dicroísmo Circular/métodos , Oligonucleotídeos/química , Varredura Diferencial de Calorimetria/métodos , Viscosidade , Espectroscopia de Ressonância Magnética/métodos , Solubilidade , Termodinâmica , Quadruplex G , Estabilidade de Medicamentos , Humanos
3.
AAPS PharmSciTech ; 25(6): 141, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898204

RESUMO

Chemotherapeutic agents often lack specificity, intratumoral accumulation, and face drug resistance. Targeted drug delivery systems based on nanoparticles (NPs) mitigate these issues. Poly (lactic-co-glycolic acid) (PLGA) is a well-studied polymer, commonly modified with aptamers (Apts) for cancer diagnosis and therapy. In this study, silybin (SBN), a natural agent with established anticancer properties, was encapsulated into PLGA NPs to control delivery and improve its poor solubility. The field-emission scanning electron microscopy (FE-SEM) showed spherical and uniform morphology of optimum SBN-PLGA NPs with 138.57±1.30nm diameter, 0.202±0.004 polydispersity index (PDI), -16.93±0.45mV zeta potential (ZP), and 70.19±1.63% entrapment efficiency (EE). The results of attenuated total reflectance-Fourier transform infrared (ATR-FTIR) showed no chemical interaction between formulation components, and differential scanning calorimetry (DSC) thermograms confirmed efficient SBN entrapment in the carrier. Then, the optimum formulation was functionalized with 5TR1 Apt for active targeted delivery of SBN to colorectal cancer (CRC) cells in vitro. The SBN-PLGA-5TR1 nanocomplex released SBN at a sustained and constant rate (zero-order kinetic), favoring passive delivery to acidic CRC environments. The MTT assay demonstrated the highest cytotoxicity of the SBN-PLGA-5TR1 nanocomplex in C26 and HT29 cells and no significant cytotoxicity in normal cells. Apoptosis analysis supported these results, showing early apoptosis induction with SBN-PLGA-5TR1 nanocomplex which indicated this agent could cause programmed death more than necrosis. This study presents the first targeted delivery of SBN to cancer cells using Apts. The SBN-PLGA-5TR1 nanocomplex effectively targeted and suppressed CRC cell proliferation, providing valuable insights into CRC treatment without harmful effects on healthy tissues.


Assuntos
Neoplasias Colorretais , Sistemas de Liberação de Medicamentos , Ácido Láctico , Nanopartículas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Silibina , Humanos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Silibina/administração & dosagem , Silibina/farmacologia , Silibina/química , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Nanopartículas/química , Ácido Láctico/química , Sistemas de Liberação de Medicamentos/métodos , Silimarina/química , Silimarina/administração & dosagem , Silimarina/farmacologia , Portadores de Fármacos/química , Linhagem Celular Tumoral , Ácido Poliglicólico/química , Tamanho da Partícula , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/administração & dosagem , Sobrevivência Celular/efeitos dos fármacos , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Antineoplásicos/química , Solubilidade , Células HT29 , Liberação Controlada de Fármacos , Varredura Diferencial de Calorimetria/métodos
4.
J Pharm Biomed Anal ; 246: 116201, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38788621

RESUMO

Patient can be exposed to the photodegradation products of a drug after skin application of topical formulations. NSAIDs, with analgesic and anti-inflammatory properties, are known for the potential photoinstability, and are applied often in the form of creams, gels or liquids, commonly used among athletes, elderly people, geriatric patients and patients treated with multidrug therapies. Susceptibility to photodegradation hazard of those group arises the need for development of a new approach, with the ability to evaluate the patient safety. We planned to use a rapid assessment procedure (RAP) of safety by testing the photostability of popular skin medicinal products. This method, proposed many years ago by WHO, is now reintroduced to analytical applications in industry, when emergency drugs (e.g. for Covid) are implemented to the market in accelerated procedures. In the health care system, qualitative evaluation of drugs is extremely valuable, therefore we have planned to identify photodegradation using the FTIR method - infrared spectroscopy and DSC - differential scanning calorimetry, whilst the risk of formation of genotoxic products using the Ames test. We have successfully demonstrated that changes in the chemical structure and physical form of both pure APIs and drug products containing the API be assessed in a short time. Another advantage of our work is the combination of the developed results from FTIR/NIR spectra with statistical analysis. As a result, full and quick qualitative assessment of the effects of photoexposure of selected NSAIDs is performed, fortunately showing no mutagenicity. Due to the popularity of NSAIDs applied to the skin, a gel containing naproxen and spray with indomethacin were selected for testing. The analysis carried out for various formulations of both preparations allows us to demonstrate the universality of the applied RAP methods in assessing the risk of hazard to the patient, thus we present research results that expand or widen the knowledge and assessment of risks related to the use of drugs on the skin.


Assuntos
Anti-Inflamatórios não Esteroides , Indometacina , Naproxeno , Fotólise , Pele , Anti-Inflamatórios não Esteroides/química , Naproxeno/química , Naproxeno/análise , Indometacina/química , Humanos , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Varredura Diferencial de Calorimetria/métodos , Administração Cutânea , Estabilidade de Medicamentos
5.
Pharm Dev Technol ; 29(5): 530-540, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38713634

RESUMO

OBJECTIVE: Posaconazole (PCZ) is an antifungal drug, which acts by inhibiting the lanosterol-14α-demethylase enzyme. It is a biopharmaceutical classification system class II drug with its bioavailability being limited by poor aqueous solubility. The aim of this study was to improve the oral bioavailability of PCZ by preparing nanocrystalline solid dispersion (NCS). METHODS: PCZ-NCS was prepared by a combination of precipitation and high-pressure homogenization followed by freeze-drying. Several different surfactants and polymers were screened to produce NCS with smaller particle size and higher stability. RESULTS: The optimized NCS formulation containing 0.2% Eudragit S100 and 0.2% SLS was found to provide the average particle size of 73.31 ± 4.7 nm with a polydispersity index of 0.23 ± 0.03. Scanning electron microscopy revealed the preparation of homogeneous and rounded particles. Differential scanning calorimetry and X-ray diffraction confirmed crystalline nature of NCS. Nanonization increased the saturation solubility of PCZ by about 18-fold in comparison with the neat drug. Intrinsic dissolution study showed 93% dissolution of PCZ within the first 10 min. In vivo pharmacokinetic study in Wistar rats showed that Cmax and AUCtotal of PCZ-NCS increased by 2.58- and 2.64-fold compared to the marketed formulation. CONCLUSION: PCZ-NCS formulation presents a viable approach for enhancing the oral bioavailability of PCZ.


Assuntos
Antifúngicos , Disponibilidade Biológica , Nanopartículas , Tamanho da Partícula , Ratos Wistar , Solubilidade , Triazóis , Animais , Nanopartículas/química , Triazóis/farmacocinética , Triazóis/administração & dosagem , Triazóis/química , Antifúngicos/administração & dosagem , Antifúngicos/farmacocinética , Ratos , Masculino , Administração Oral , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Difração de Raios X/métodos , Liofilização , Química Farmacêutica/métodos , Tensoativos/química , Varredura Diferencial de Calorimetria/métodos
6.
Mol Pharm ; 21(6): 3027-3039, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38755753

RESUMO

This study presents a novel approach by utilizing poly(vinylpyrrolidone)s (PVPs) with various topologies as potential matrices for the liquid crystalline (LC) active pharmaceutical ingredient itraconazole (ITZ). We examined amorphous solid dispersions (ASDs) composed of ITZ and (i) self-synthesized linear PVP, (ii) self-synthesized star-shaped PVP, and (iii) commercial linear PVP K30. Differential scanning calorimetry, X-ray diffraction, and broad-band dielectric spectroscopy were employed to get a comprehensive insight into the thermal and structural properties, as well as global and local molecular dynamics of ITZ-PVP systems. The primary objective was to assess the influence of PVPs' topology and the composition of ASD on the LC ordering, changes in the temperature of transitions between mesophases, the rate of their restoration, and finally the solubility of ITZ in the prepared ASDs. Our research clearly showed that regardless of the PVP type, both LC transitions, from smectic (Sm) to nematic (N) and from N to isotropic (I) phases, are effectively suppressed. Moreover, a significant difference in the miscibility of different PVPs with the investigated API was found. This phenomenon also affected the solubility of API, which was the greatest, up to 100 µg/mL in the case of starPVP 85:15 w/w mixture in comparison to neat crystalline API (5 µg/mL). Obtained data emphasize the crucial role of the polymer's topology in designing new pharmaceutical formulations.


Assuntos
Varredura Diferencial de Calorimetria , Itraconazol , Cristais Líquidos , Povidona , Solubilidade , Difração de Raios X , Itraconazol/química , Cristais Líquidos/química , Povidona/química , Varredura Diferencial de Calorimetria/métodos , Difração de Raios X/métodos , Polímeros/química , Antifúngicos/química , Composição de Medicamentos/métodos , Cristalização , Química Farmacêutica/métodos
7.
Mol Pharm ; 21(6): 2838-2853, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38662637

RESUMO

Levofloxacin hemihydrate (LVXh) is a complex fluoroquinolone drug that exists in both hydrated and anhydrous/dehydrated forms. Due to the complexity of such a compound, the primary aim of this study was to investigate the amorphization capabilities and solid-state transformations of LVXh when exposed to mechanical treatment using ball milling. Spray drying was utilized as a comparative method for investigating the capabilities of complete LVX amorphous (LVXam) formation. The solid states of the samples produced were comprehensively characterized by powder X-ray diffraction, thermal analysis, infrared spectroscopy, Rietveld method, and dynamic vapor sorption. The kinetics of the process and the quantification of phases at different time points were conducted by Rietveld refinement. The impact of the different mills, milling conditions, and parameters on the composition of the resulting powders was examined. A kinetic investigation of samples produced using both mills disclosed that it was in fact possible to partially amorphize LVXh upon mechanical treatment. It was discovered that LVXh first transformed to the anhydrous/dehydrated form γ (LVXγ), as an intermediate phase, before converting to LVXam. The mechanism of LVXam formation by ball milling was successfully revealed, and a new method of forming LVXγ and LVXam by mechanical forces was developed. Spray drying from water depicted that complete amorphization of LVXh was possible. The amorphous form of LVX had a glass transition temperature of 80 °C. The comparison of methods highlighted that the formation of LVXam is thus both mechanism- and process-dependent. Dynamic vapor sorption studies of both LVXam samples showed comparable stability properties and crystallized to the most stable hemihydrate form upon analysis. In summary, this work contributed to the detailed understanding of solid-state transformations of essential fluoroquinolones while employing greener and more sustainable manufacturing methods.


Assuntos
Levofloxacino , Difração de Raios X , Levofloxacino/química , Difração de Raios X/métodos , Pós/química , Cinética , Composição de Medicamentos/métodos , Antibacterianos/química , Varredura Diferencial de Calorimetria/métodos , Cristalização , Química Farmacêutica/métodos
8.
Int J Biol Macromol ; 267(Pt 2): 131285, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38583841

RESUMO

Thermal stability and iron saturation of lactoferrin (LF) are of great significance not only for the evaluation of the biological activities of LF but also for the optimization of the isolation and drying process parameters. Differential scanning calorimetry (DSC) is a well-established and efficient method for thermal stability and iron saturation detection in LF. However, multiple DSC measurements are typically performed sequentially, thus time-consuming and low throughput. Herein, we introduced the differential scanning fluorimetry (DSF) approach to overcome such limitations. The DSF can monitor LF thermal unfolding with a commonly available real-time PCR instrument and a fluorescent dye (SYPRO orange or Glomelt), and the measured melting temperature of LF is consistent with that determined by DSC. On the basis of that, a new quantification method was established for determination of iron saturation levels using the linear correlation of the degree of ion saturation of LF with DSF measurements. Such DSF method is simple, inexpensive, rapid (<15 min), and high throughput (>96 samples per experiment), and provides a valuable alternative tool for thermal stability detection of LF and other whey proteins.


Assuntos
Fluorometria , Ferro , Lactoferrina , Estabilidade Proteica , Lactoferrina/química , Lactoferrina/análise , Ferro/química , Fluorometria/métodos , Varredura Diferencial de Calorimetria/métodos , Temperatura , Ensaios de Triagem em Larga Escala/métodos
9.
Mol Pharm ; 21(5): 2555-2564, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38551918

RESUMO

Poloxamer 188 (P188) was hypothesized to be a dual functional excipient, (i) a stabilizer in frozen solution to prevent ice-surface-induced protein destabilization and (ii) a bulking agent to provide elegant lyophiles. Based on X-ray diffractometry and differential scanning calorimetry, sucrose, in a concentration-dependent manner, inhibited P188 crystallization during freeze-drying, while trehalose had no such effect. The recovery of lactate dehydrogenase (LDH), the model protein, was evaluated after reconstitution. While low LDH recovery (∼60%) was observed in the lyophiles prepared with P188, the addition of sugar improved the activity recovery to >85%. The secondary structure of LDH in the freeze-dried samples was assessed using infrared spectroscopy, and only moderate structural changes were observed in the lyophiles formulated with P188 and sugar. Thus, P188 can be a promising dual functional excipient in freeze-dried protein formulations. However, P188 alone does not function as a lyoprotectant and needs to be used in combination with a sugar.


Assuntos
Varredura Diferencial de Calorimetria , Excipientes , Liofilização , Poloxâmero , Trealose , Liofilização/métodos , Poloxâmero/química , Excipientes/química , Trealose/química , Varredura Diferencial de Calorimetria/métodos , Sacarose/química , Difração de Raios X , L-Lactato Desidrogenase/metabolismo , L-Lactato Desidrogenase/química , Cristalização/métodos , Química Farmacêutica/métodos , Proteínas/química , Composição de Medicamentos/métodos , Congelamento
10.
Braz. J. Pharm. Sci. (Online) ; 60: e22542, 2024. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1533990

RESUMO

We developed poly-ε-caprolactone (PCL)-based nanoparticles containing D-α-tocopherol polyethylene glycol-1000 succinate (TPGS) or Poloxamer 407 as stabilizers to efficiently encapsulate genistein (GN). Two formulations, referred to as PNTPGS and PNPol, were prepared using nanoprecipitation. They were characterized by size and PDI distribution, zeta potential, nanoparticle tracking analysis (NTA), GN association (AE%), infrared spectroscopy (FT-IR), and differential scanning calorimetry (DSC). PNTPGS-GN exhibited a particle size of 141.2 nm, a PDI of 0.189, a zeta potential of -32.9 mV, and an AE% of 77.95%. PNPol-GN had a size of 146.3 nm, a better PDI than PNTPGS-GN (0.150), a less negative zeta potential (-21.0 mV), and an AE% of 68.73%. Thermal and spectrometric analyses indicated that no new compounds were formed, and there was no incompatibility detected in the formulations. Cellular studies revealed that Poloxamer 407 conferred less toxicity to PCL nanoparticles. However, the percentage of uptake decreased compared to the use of TPGS, which exhibited almost 80% cellular uptake. This study contributes to the investigation of stabilizers capable of conferring stability to PCL nanoparticles efficiently encapsulating GN. Thus, the PCL nanoparticle proposed here is an innovative nanomedicine for melanoma therapy and represents a strong candidate for specific pre-clinical and in vivo studie


Assuntos
Genisteína/farmacologia , Nanopartículas/análise , Melanoma/tratamento farmacológico , Tamanho da Partícula , Análise Espectral/classificação , Varredura Diferencial de Calorimetria/métodos , Cromatografia Líquida de Alta Pressão/métodos
11.
Food Chem ; 420: 136002, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37060671

RESUMO

The high ß-glucan content in barley disrupts the gluten network in dough. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FTIR), and solid-state nuclear magnetic resonance (NMR) techniques were used to clarify how ß-glucan affected the quality of the gluten network structure with ß-glucan contents of 0-2%. The results suggest that the physical hindrance of the ß-glucan gel destroyed the formation of the gluten network structure. When 1.0-2.0% ß-glucan was added, the percentage of α-helical structures increased significantly. When the added amount of ß-glucan reached 2.0%, the sulfhydryl group (SH) content increased from 8.06 to 10.27 µmol/g, and the disulfide bond (SS) content decreased from 240.09 to 217.38 µmol/g. The interaction between ß-glucan and gluten mainly resulted from the interaction of electron-withdrawing groups, such as carbonyl groups (CO) and double bond carbons (CC), and carbon atoms on the side chains of ß-glucan, which play an important role in the central structure of glutenin.


Assuntos
Hordeum , beta-Glucanas , beta-Glucanas/química , Hordeum/química , Varredura Diferencial de Calorimetria/métodos
12.
Braz. J. Pharm. Sci. (Online) ; 59: e21217, 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1429971

RESUMO

Abstract Solid dispersions (SDs) of ursolic acid (UA) were developed using polyvinylpyrrolidone K30 (PVP K30) in combination with non-ionic surfactants, such as D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) or poloxamer 407 (P407) with the aim of enhancing solubility and in vitro release of the UA. SDs were investigated using a 24 full factorial design, subsequently the selected formulations were characterized for water solubility, X-ray diffractometry (XRD), differential scanning calorimetry (DSC), particle diameter, scanning electron microscopy, drug content, physical-chemical stability and in vitro release profile. SDs showed higher UA water-solubility than physical mixtures (PMs), which was attributed by transition of the drug from crystalline to amorphous or molecular state in the SDs, as indicated by XRD and DSC analyses. SD1 (with P407) and SD2 (with TPGS) were chosen for further investigation because they had higher drug load. SD1 proved to be more stable than SD2, revealing that P407 contributed to ensure the stability of the UA. Furthermore, SD1 and SD2 increased UA release by diffusion and swelling-controlled transport, following the Weibull model. Thus, solid dispersions obtained with PVP k-30 and P407 proved to be advantageous to enhance aqueous solubility and stability of UA.


Assuntos
Polietilenoglicóis/administração & dosagem , Solubilidade , Poloxâmero/efeitos adversos , Difusão , Raios X/efeitos adversos , Técnicas In Vitro , Varredura Diferencial de Calorimetria/métodos , Preparações Farmacêuticas/análise , Microscopia Eletrônica de Varredura/métodos
13.
Braz. J. Pharm. Sci. (Online) ; 59: e22505, 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1439507

RESUMO

Abstract Natural products are considered an important source of the therapeutic arsenal currently available. Among these alternatives are the seeds of Ambrosia peruviana (altamisa), whose extract has shown an anti-inflammatory effect. The main objective of this work was to perform a preformulation study of Ambrosia peruviana seeds ethanolic extract, where the main factors that affect the physical, chemical, and pharmacological stability of the extract were evaluated, as well as a compatibility study by differential scanning calorimetry (DSC) analysis against different excipients. A dry extract was obtained by rotary evaporation of the seeds macerated with 96% ethanol. The anti-inflammatory activity was determined by measuring its effect on NO production in RAW 264.7 macrophages, stimulated with LPS. The results showed that the dry extract maintained its stability over time when stored at a temperature of 4 and 25ºC, demonstrating its biological activity, the content of phenolic compounds, and its physicochemical parameters remain practically invariable. However, when exposed to high temperatures (60 ºC) it was affected. The thermal analysis revelated that the behavior of most of the selected excipients and the dry extract was maintained, which indicates that it did not present incompatibilities, therefore they can be candidates for formulating a microemulsion.


Assuntos
Sementes/metabolismo , Asteraceae/classificação , Ambrosia/efeitos adversos , Produtos Biológicos , Varredura Diferencial de Calorimetria/métodos , Excipientes/administração & dosagem
14.
Carbohydr Polym ; 283: 119148, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35153017

RESUMO

In order to provide a theoretical basis on how germination treatment modulated the pasting behaviors of starches from native and germinated waxy brown rice, impacts of germination on the molecular and supramolecular structures and pasting behaviors were evaluated. Multiple analytical methods such as thermodynamics and spectroscopy were applied in this work for investigating the changes in starch multiscale structure and pasting behaviors. The results show that germination treatment contributed to an obvious increase in α- and ß-amylase activities, which could degrade the starch chains and reduce the contents of double helices (50.9%-43.2%), short-range ordered degree (1.054-0.908), relative crystallinity (40.1%-30.5%), and lamellar ordering degree (dc, 6.09-5.46 nm) along with apparent erosion on starch granules. These structural amorphizations at the molecular and supramolecular levels could lead to the weakened entanglements and interactions among molecular chains, eventually reducing the characteristic viscosity (e.g., overall, peak, and final viscosity) of starch. This study may facilitate better development of germinated rice-based products.


Assuntos
Oryza/química , Amido/química , Amilopectina/química , Varredura Diferencial de Calorimetria/métodos , Germinação , Espectroscopia de Ressonância Magnética/métodos , Microscopia Eletrônica de Varredura/métodos , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Temperatura , Termodinâmica , Viscosidade , Ceras/química
15.
Int J Mol Sci ; 23(3)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35163317

RESUMO

Amphiphilic copolymers are appealing materials because of their interesting architecture and tunable properties. In view of their application in the biomedical field, the preparation of these materials should avoid the use of toxic compounds as catalysts. Therefore, enzymatic catalysis is a suitable alternative to common synthetic routes. Pentablock copolymers (CUC) were synthesized with high yields by ring-opening polymerization of ε-caprolactone (ε-CL) initiated by Pluronic (EPE) and catalyzed by Candida antarctica lipase B enzyme. The variables to study the structure-property relationship were EPEs' molecular weight and molar ratios between ε-CL monomer and EPE macro-initiator (M/In). The obtained copolymers were chemically characterized, the molecular weight determined, and morphologies evaluated. The results suggest an interaction between the reaction time and M/In variables. There was a correlation between the differential scanning calorimetry data with those of X-ray diffraction (WAXD). The length of the central block of CUC copolymers may have an important role in the crystal formation. WAXD analyses indicated that a micro-phase separation takes place in all the prepared copolymers. Preliminary cytotoxicity experiments on the extracts of the polymer confirmed that these materials are nontoxic.


Assuntos
Caproatos/química , Lactonas/química , Poloxâmero/química , Polímeros/química , Varredura Diferencial de Calorimetria/métodos , Catálise , Peso Molecular , Polimerização
16.
J Pharm Pharmacol ; 74(1): 41-56, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34986225

RESUMO

OBJECTIVES: In this study, p-sulfonatocalix[6]arenes (SCA6) was proposed to construct a host-guest complexation to carry mitoxantrone (MIT) to maintain its anti-proliferation effect on HepG2 cells as well as to attenuate cardiotoxicity on H9C2 cells as a nano-size drug delivery system. METHODS: SCA6 binding to MIT evidenced through competitive fluorescence titration method. The complex was characterized using UV-visible, Fourier transform infrared, and proton nuclear magnetic resonance (1H-NMR) spectroscopies and differential scanning calorimetry analysis. The cytotoxicity was examined by a cell counting kit-8 assay on six cells. High content analysis, cell apoptosis and cell cycle experiments were measured to investigate the mechanism of detoxification in H9C2. KEY FINDINGS: The host-guest complexation was formed with a stoichiometry ratio of 1:1. Cytotoxicity study demonstrated that MIT/SCA6 complex could improve the cell viability on H9C2, MCF-7, A549, Hek293 and L02 cells and remained cytotoxicity effect on HepG2 cells. High content analysis showed that MIT/SCA6 complex could enhance the cell viability, mitochondrial mass and mitochondrial membrane potential and ameliorate the nuclear swelling on H9C2 cells. Moreover, the complex were arrested in G0/G1 phase of the cell cycle and same with MIT, while the detoxication was attributed to reducing early apoptosis. CONCLUSIONS: The host-guest complexation between SCA6 and MIT had the ability to attenuate cardiotoxicity and provided a potential strategy for the application of soluble calixarenes in chemotherapy.


Assuntos
Calixarenos/farmacologia , Cardiotoxicidade , Estabilidade de Medicamentos , Mitoxantrona , Fenóis/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Varredura Diferencial de Calorimetria/métodos , Cardiotoxicidade/etiologia , Cardiotoxicidade/prevenção & controle , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/farmacologia , Sistemas de Liberação de Medicamentos , Células Hep G2 , Humanos , Mitoxantrona/farmacologia , Mitoxantrona/toxicidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
17.
Carbohydr Polym ; 275: 118682, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34742412

RESUMO

Layer-by-layer three-dimensional nanofibrous scaffolds (3DENS) were produced using the electrospinning technique. Interest in using biopolymers and application of electrospinning fabrication techniques to construct nanofibers for biomedical application has led to the development of scaffolds composed of PVA, keratin, and chitosan. To date, PVA/keratin blended nanofibers and PVA/chitosan blended nanofibers have been fabricated and studied for biomedical applications. Electrospun scaffolds comprised of keratin and chitosan have not yet been reported in published literature, thus a novel nanofibrous PVA/keratin/chitosan scaffold was fabricated by electrospinning. The resulting 3DENS were characterized using fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), differential scanning colorimetry (DSC), and thermogravimetric analysis (TGA). Physiochemical properties of the polymer solutions such as viscosity (rheology) and conductivity were also investigated. The 3DENS possess a relatively uniform fibrous structure, suitable porosity, swelling properties, and degradation which are affected by the mass ratio of keratin, and chitosan to PVA. These results demonstrate that PVA/keratin/chitosan 3DENS have the potential for biomedical applications.


Assuntos
Quitosana/química , Queratinas/química , Nanofibras/química , Álcool de Polivinil/química , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/química , Biopolímeros/química , Varredura Diferencial de Calorimetria/métodos , Condutividade Elétrica , Microscopia Eletrônica de Varredura/métodos , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Termogravimetria/métodos , Engenharia Tecidual/métodos , Viscosidade
18.
Carbohydr Polym ; 276: 118788, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34823798

RESUMO

The purpose of this study was to investigate the potential of bacterial cellulose nanofiber suspension (BCNs) as stabilizer in anti-solvent precipitation and its effect on improving bioavailability of coenzyme Q10. Bacterial cellulose (BC) was hydrolyzed by sulfuric acid followed by the oxidation with hydrogen peroxide to prepare BCNs. The suspension of BCNs-loaded CoQ10 (CoQ10-BCNs) were prepared by antisolvent precipitation. The zeta potential of CoQ10-BCNs was about -36.01 mV. The properties of CoQ10, BCNs and CoQ10-BCNs were studied by scanning electron microscopy, transmission electron microscope, Fourier-transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry and thermo gravimetric analysis. The crystallinity of CoQ10 decreased in CoQ10-BCNs compared with the raw CoQ10, and CoQ10-BCNs have good physicochemical stability. In oral bioavailability studies, the area under curve (AUC) of CoQ10-BCNs was about 3.62 times higher than the raw CoQ10 in rats.


Assuntos
Celulose/química , Nanofibras/química , Polissacarídeos Bacterianos/química , Ubiquinona/análogos & derivados , Água/química , Administração Oral , Animais , Disponibilidade Biológica , Varredura Diferencial de Calorimetria/métodos , Gluconacetobacter xylinus/metabolismo , Microscopia Eletrônica de Varredura/métodos , Ratos , Ratos Sprague-Dawley , Solubilidade , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Suspensões , Termogravimetria/métodos , Ubiquinona/química , Ubiquinona/farmacocinética , Difração de Raios X/métodos
19.
Braz. J. Pharm. Sci. (Online) ; 58: e21131, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1420447

RESUMO

Abstract The study is aimed to develop a monolithic controlled matrix transdermal patches containing Metoclopramide as a model drug by solvent casting method. Eudragit L100, Polyvinylpyrrolidone K-30, and Methylcellulose were used in different ratios and Polyethylene glycol 400 added as a plasticizer. Resulting patches were evaluated for their physicochemical characters like organoleptic characters, weight variation, folding endurance, thickness, swelling index, flatness, drug content, swelling index, percentage erosion, moisture content, water vapor transmission rate and moisture uptake. Formed patches were also evaluated through Fourier transform spectroscopy (FT-IR), X-ray diffraction (XRD), Differential Scanning calorimetry (DSC) and Scanning Electron Microscopy (SEM). Results of SEM unveiled smooth surface of drug-loaded patches. In-vitro dissolution studies were conducted by using dissolution medium phosphate buffer saline pH 7.4. Effect of natural permeation enhancers was elucidated on two optimized formulations (Z4 and Z9). Different concentrations (5%-10 %) of permeation enhancers i.e. Olive oil, Castor oil and Eucalyptus oil were evaluated on Franz diffusion cell using excised abdominal rat skin. Z4-O2 (Olive oil 10%) had enhanced sustain effect and flux value (310.72) close to the desired flux value. Z4-O2 followed Higuchi release model (R2= 0.9833) with non-fickian diffusion release mechanism (n=0.612)


Assuntos
Análise Espectral/métodos , Óleos Voláteis/análise , Metoclopramida/agonistas , Difração de Raios X/instrumentação , Varredura Diferencial de Calorimetria/métodos , Microscopia Eletrônica de Varredura/métodos
20.
Braz. J. Pharm. Sci. (Online) ; 58: e19723, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1394035

RESUMO

Abstract Passiflora nitida Kunth, an Amazonian Passiflora species, is little studied, although the specie's high biological potential. Herein the plant's pharmacognostic characterization, extract production, antioxidant potential evaluation, and application of this extract in cosmetic products is reported. The physical chemical parameters analyzed were particle size by sieve analysis, loss through drying, extractive yield, total ash content, laser granulometry, specific surface area and pore diameter (SBET), differential scanning calorimetry, thermogravimetry (TG), and wave dispersive X-Ray fluorescence (WDXRF). Total phenol/flavonoid content, LC-MS/MS analysis, DPPH and ABTS antioxidant radical assays, cytotoxicity, melanin, and tyrosinase inhibition in melanocytes test provided evidence to determine the content of the major constituent. P. nitida dry extract provided a fine powder with mesopores determined by SBET, with the TG curve showing five stages of mass loss. The antioxidant potential ranged between 23.5-31.5 mg∙mL-1 and tyrosinase inhibition between 400-654 µg∙mL-1. The species presented an antimelanogenic effect and an inhibitory activity of cellular tyrosinase (26.6%) at 25 µg/mL. The LC-MS/MS analysis of the spray-dried extract displayed the main and minor phenolic compounds constituting this sample. The results indicate that P. nitida extract has promising features for the development of cosmetic formulations


Assuntos
Extratos Vegetais/análise , Folhas de Planta/efeitos adversos , Cosméticos/classificação , Passiflora/classificação , Termogravimetria/métodos , Raios X/efeitos adversos , Varredura Diferencial de Calorimetria/métodos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Compostos Fenólicos , Melaninas , Antioxidantes/efeitos adversos
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