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1.
J Chromatogr A ; 1722: 464907, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38615560

RESUMEN

Developing a reliable and effective quality evaluation system for traditional Chinese medicine (TCM) is both challenging and crucial for its advancement. This study employs fingerprinting techniques to establish precise and comprehensive quality control for TCM, taking Xuezhikang capsules as an example and aiming to facilitate the internationalization of TCM. The "double wavelength absorption coefficient ratio fingerprint" and "Reliability theory" are developed to determine the fingerprint peak purity and fingerprint reliability respectively. Subsequently, the dual-wavelength fusion fingerprint was obtained to avoid the limitations of a single wavelength. In addition, an electrochemical fingerprint (ECFP) was obtained to assess the similarity of electroactive components in the sample, and the Differential Scanning Calorimetry quantized fingerprint (DSC QFP) was introduced for thermal analysis. Fingerprint-efficacy correlations between PL-EC* and dual-wavelength fusion fingerprint (DWFFP) provided valuable insights that there are 76.6 % of the fingerprint compounds exhibited electroactivity. Finally, samples were classified into grades 1∼3 by combining DWFFP, ECFP and DSC QFP through the mean method, meeting the evaluation standard (SL-M > 0.9, PL-M between 80 % and 120 %). This study provides valuable information for ensuring the quality of TCM products, which represents a significant step forward in enhancing the reliability and authenticity of TCM products.


Asunto(s)
Rastreo Diferencial de Calorimetría , Medicamentos Herbarios Chinos , Técnicas Electroquímicas , Medicina Tradicional China , Control de Calidad , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Técnicas Electroquímicas/métodos , Reproducibilidad de los Resultados , Cromatografía Líquida de Alta Presión/métodos
2.
Food Chem ; 444: 138631, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38325079

RESUMEN

Naringenin (NGE), a typical flavanone abundant in citrus fruits, exhibits remarkable antioxidant activities. However, its low solubility in oil restricts its widespread use in inhibiting lipid oxidation. In this study, we present a novel and effective approach to address this limitation by developing a naringenin-phospholipid complex (NGE-PC COM). Comprehensive analytical techniques including Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), and X-ray diffraction (XRD) were employed to confirm the formation of the NGE-PC COM and elucidate the interaction mechanism between NGE and phospholipids molecules. Notably, the oil-solubility of NGE was significantly enhanced by approximately 2700-fold when formulated as a phospholipid complex in soybean oil. The improved oil-solubility of NGE-PC COM enabled effective inhibition of oil thermal oxidation under high temperature conditions. Generally, this investigation proposed a novel and promising strategy for employing flavanones with strong antioxidant activities to enhance the thermal oxidative stability of edible oil during heating processes.


Asunto(s)
Flavanonas , Fosfolípidos , Fosfolípidos/química , Aceite de Soja , Antioxidantes , Calefacción , Flavanonas/química , Solubilidad , Estrés Oxidativo , Rastreo Diferencial de Calorimetría , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Difracción de Rayos X
3.
Biomacromolecules ; 24(8): 3463-3471, 2023 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-37506046

RESUMEN

In DNA, thymine typically forms hydrogen bonds with adenine to hold two complementary strands together and to preserve the genetic code. While thymine is typically absent in RNA, a thymine-thymine hydrogen bonding structure is reminiscent of the wobble region in tRNA recognition, where noncanonical base pairing can occur. This noncanonical base pairing can be applied to synthetic polymer systems, where thymine is free to hydrogen bond with itself. In this work, the natural hydrogen bonding capacity of thymine was used to produce silicone polymer systems designed to be cross-linked by hydrogen bonds. Backbone and end-group-modified silicones were synthesized with differing concentrations of thymine, which facilitated the cross-linking of the polymeric strands. Removing the hydrogen on N3─which is typically involved in hydrogen bonding─resulted in systems with similar viscosities to the starting material and that were devoid of any apparent cross-links. Differential scanning calorimetry (DSC) studies of the thymine-modified polymers displayed thermal absorptions and releases, indicative of bond breaking and reformation, around 100 and 60 °C, respectively. The cycle of bond breaking and formation could be repeated without any noticeable degradation of the chemical structure of the polymers. These polymeric materials could be readily recycled and remolded by heating them at 110 °C for 5 min, followed by cooling to room temperature, confirming their thermoplastic nature.


Asunto(s)
Polímeros , Timina , Timina/química , Polímeros/química , Emparejamiento Base , ADN/química , Rastreo Diferencial de Calorimetría , Enlace de Hidrógeno
4.
Elife ; 122023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37334968

RESUMEN

Highly concentrated antibody formulations are oftentimes required for subcutaneous, self-administered biologics. Here, we report the development of a unique formulation for our first-in-class FSH-blocking humanized antibody, MS-Hu6, which we propose to move to the clinic for osteoporosis, obesity, and Alzheimer's disease. The studies were carried out using our Good Laboratory Practice (GLP) platform, compliant with the Code of Federal Regulations (Title 21, Part 58). We first used protein thermal shift, size exclusion chromatography, and dynamic light scattering to examine MS-Hu6 concentrations between 1 and 100 mg/mL. We found that thermal, monomeric, and colloidal stability of formulated MS-Hu6 was maintained at a concentration of 100 mg/mL. The addition of the antioxidant L-methionine and chelating agent disodium EDTA improved the formulation's long-term colloidal and thermal stability. Thermal stability was further confirmed by Nano differential scanning calorimetry (DSC). Physiochemical properties of formulated MS-Hu6, including viscosity, turbidity, and clarity, confirmed with acceptable industry standards. That the structural integrity of MS-Hu6 in formulation was maintained was proven through Circular Dichroism (CD) and Fourier Transform Infrared (FTIR) Spectroscopy. Three rapid freeze-thaw cycles at -80 °C/25 °C or -80 °C/37 °C further revealed excellent thermal and colloidal stability. Furthermore, formulated MS-Hu6, particularly its Fab domain, displayed thermal and monomeric storage stability for more than 90 days at 4°C and 25°C. Finally, the unfolding temperature (Tm) for formulated MS-Hu6 increased by >4.80 °C upon binding to recombinant FSH, indicating highly specific ligand binding. Overall, we document the feasibility of developing a stable, manufacturable and transportable MS-Hu6 formulation at a ultra-high concentration at industry standards. The study should become a resource for developing biologic formulations in academic medical centers.


Asunto(s)
Anticuerpos Monoclonales , Hormona Folículo Estimulante , Anticuerpos Monoclonales/química , Temperatura , Rastreo Diferencial de Calorimetría , Viscosidad , Estabilidad Proteica
5.
Sci Rep ; 13(1): 9792, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37328603

RESUMEN

The need for more economical catalysts for various combustion reactions is continuously driving catalyst development. We present Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC) as suitable techniques for fast examination of catalyst activity for combustion reactions. The heat of reaction ΔHr generated at the catalyst in a combustible atmosphere is the measure for estimating the capability of the catalyst. Present investigations verify the reliability of both methods for the pre-selection of catalysts for further extensive investigations. To simplify the measurements and the result evaluation, a new measurement routine is introduced which is more suitable for rapid catalyst investigation than the conventional approach. For initial investigations, oxidation of 1% methane on a cobalt oxide catalyst was used. First, DTA measurements were performed. The vessel size and the amount of catalyst are considered as factors influencing the thermal signal. Simultaneous mass spectrometry measurements were used to better understand the formation of the DTA response. Comparable DSC investigations were then conducted. Finally, the behavior of catalyst was compared with two commercial palladium/alumina catalysts using DTA and DSC. Our investigations show that DTA and DSC are powerful methods to identify potential catalysts in a fast and reproducible manner, provided that all parameters influencing the thermal signal are kept constant.


Asunto(s)
Óxido de Aluminio , Reproducibilidad de los Resultados , Catálisis , Oxidación-Reducción , Óxido de Aluminio/química , Rastreo Diferencial de Calorimetría
6.
J Ethnopharmacol ; 311: 116442, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37004746

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Zhizi Jinhua Pills (ZZJHP), a compound preparation composed of 8 traditional Chinese medicines (TCM), is widely used clinically to clearing heat, purging fire, cooling blood and detoxifying. However, the studies on its pharmacological activity and the determination of active compounds are relatively few. There is a lack of quality control methods that can reflect the effectiveness of the drug. AIM OF THE STUDY: The objective was to construct fingerprint profiles, conduct a spectrum-effect relationship study and establish an overall quality control method for ZZJHP through anti-inflammatory and redox activity studies. MATERIALS AND METHODS: Firstly, anti-inflammatory activity was tested using the xylene-induced ear edema model in mice. Then, Five-wavelength fusion HPLC fingerprint, electrochemical fingerprint, and Differential scanning calorimetry (DSC) profiling were established to evaluate ZZJHP more comprehensively, where Euclidean quantified fingerprint method (EQFM) was proposed for the similarity assessment of these three fingerprints. Moreover, the spectrum-activity relationship of HPLC-FP and DSC-FP with electrochemical activity helped explore the active components or ranges in the fingerprint. Finally, integrated analysis of HPLC, DSC and electrochemistry were used for the quality screen of samples from different manufacturers. RESULTS: ZZJHP was found to significantly decrease the levels of both TNF-α and IL-6 in the mice. Qualitatively, the integrated similarity Sm of 21 samples were all greater than 0.9, indicating the great consistency in chemical composition. Quantitatively, 9 batches of samples were classified as Grade1∼4; 6 batches of samples were classified as Grade5∼7 due to higher PINT; 6 batches of samples were classified as Grade4∼5 due to lower PINT. EQFM can qualitatively and quantitatively characterize the fingerprint profile information from an overall perspective. CONCLUSIONS: This strategy will contribute to the quantitative characterization of TCM and promote the application of fingerprint technology in the phytopharmacy field.


Asunto(s)
Medicamentos Herbarios Chinos , Animales , Ratones , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/análisis , Cromatografía Líquida de Alta Presión/métodos , Rastreo Diferencial de Calorimetría , Electroquímica , Medicina Tradicional China
7.
Food Chem ; 405(Pt B): 134996, 2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-36435104

RESUMEN

Thermal properties of extra virgin olive oil (EVOO) consumed in China were investigated through differential scanning calorimetry (DSC), Principal Component Analysis (PCA) dimension reduction analysis combined with K-nearest neighbors (KNN) and support vector machine (SVM) models were used to determine whether oil samples would be EVOO. Both models exhibited a 100% ability to distinguish EVOO from non-EVOO. Additionally, the discrimination test of canola oil was still limited from EVOO adulteration due to its similarity of cooling profiles with EVOO. Canola oil was artificially added into EVOO in 5%, 10%, 20% and 30% and DSC test results collected were detected in computer models. Both models effectively identified even 5% canola oil adulterated in EVOO; however, KNN (93.75%) model exhibited much higher accuracy than SVM (43.92%). In conclusion, DSC combined with KMN model analysis was more available for the adulteration detection of EVOO.


Asunto(s)
Contaminación de Medicamentos , Aceite de Brassica napus , Aceite de Oliva , China , Rastreo Diferencial de Calorimetría
8.
Molecules ; 27(21)2022 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-36364323

RESUMEN

The aim of this study was to conduct thermal characterization of sesame seeds and oils from various geographical origins (Ethiopia, India, Nigeria, Sudan, Turkey), different method of extraction (hexane and cold-pressing), and different types of derived products (halva and tahini). Thermal characterization was investigated using differential scanning calorimetry (DSC), which showed that origin of the seeds has no influence on the melting profile of sesame oil (peak temperature and enthalpy). Method of extraction (hexane and cold-pressing) influenced the peak temperatures of the resulting oils (p ≤ 0.05). The addition of 20% of palm olein to pure sesame oil influenced the significant changes in thermodynamic parameters such as peak temperature (Tm2), which was lowered from −5.89 °C to −4.99 °C, peak half width (T1/2), elevated from 3.01 °C to 4.52 °C, and the percentage of first peak area (% peak 1) lowered from 87.9 to 73.2% (p ≤ 0.05). The PCA method enabled to distinguish authentic and adulterated sesame oils of various origins. There were no significant differences in thermal properties among the products (halva, tahini) and the authentic sesame oil (p > 0.05). The obtained results showed DSC feasibility to characterize sesame oil and sesame products in terms of authenticity.


Asunto(s)
Sesamum , Sesamum/química , Aceite de Sésamo/química , Rastreo Diferencial de Calorimetría , Hexanos , Semillas/química
9.
Int J Pharm ; 628: 122347, 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36349613

RESUMEN

Bentonite (BT) is a biocompatible clay mineral that has advantageous properties as a pharmaceutical excipient. However, the application of BT in controlled-release oral formulations has been challenging due to incomplete drug release from BT-drug complexes. The objective of this study was to investigate the effect of modifying BT with zwitterionic phosphatidylcholine (PC) to enhance the dissolution of drugs, thereby increasing their oral bioavailability. Quetiapine (QTP) was chosen as a model drug, and the composition of the complex (BT-PC-QTP) was optimized to have the maximum QTP content and increase the total amount of QTP released. The in vitro release study showed that the incorporation of an appropriate amount of PC into BT improved the low release rate of the BT-QTP complex at pH 7.4, while the pH-dependent release property of BT was maintained. In an in vivo pharmacokinetic study in rats, the oral administration of the BT-PC-QTP complex showed significantly higher Cmax and AUC values than the BT-QTP complex. Moreover, BT-PC-QTP showed a 2.4-fold enhancement of oral bioavailability compared to the QTP powder group. The scanning electron microscopy (SEM), powder X-ray diffraction (pXRD), and differential scanning calorimetry (DSC) studies confirmed that the intercalation of PC and QTP into BT resulted in the adsorption of QTP in an amorphous state. The characterization of the nanoparticles generated from the BT-PC-QTP complex supported that PC enhanced the dissolution of QTP by forming nanosized PC particles. Taken together, the modification of BT with PC can be applied in pharmaceutical industry as a platform strategy to control the release of the BT-drug complex and enhance the oral bioavailability of poorly water-soluble drugs.


Asunto(s)
Bentonita , Lecitinas , Ratas , Animales , Disponibilidad Biológica , Liberación de Fármacos , Fumarato de Quetiapina , Solubilidad , Polvos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Rastreo Diferencial de Calorimetría , Administración Oral , Difracción de Rayos X , Preparaciones de Acción Retardada
10.
Natal; s.n; 28/11/2022. 55 p. ilus, tab, graf.
Tesis en Portugués | LILACS, BBO | ID: biblio-1510707

RESUMEN

A engenharia de tecidos ósseos é um ramo importante da medicina regenerativa e envolve o desenvolvimento de arcabouços com composição e arquitetura favoráveis à integração celular, além do estudo de fatores capazes de promover a adesão e proliferação celular, incluindo estímulos químicos e biofísicos. O objetivo do estudo foi avaliar a utilização do laser de baixa intensidade (LBI) como uma ferramenta para promover a bioestimulação in vitro de células osteoblásticas cultivadas em arcabouços nanofibrosos de ácido polilático (PLA). Os arcabouços foram produzidos pela técnica de eletrofiação e caracterizados quanto à molhabilidade, composição pela espectroscopia no infravermelho por transformada de Fourier (FTIR), morfologia da superfície por microscópica eletrônica de varredura (MEV), caracterização termogravimétrica (TGA), calorimetria diferencial exploratória (DSC) e cristalinidade por difração de raios-X (DRX). Os ensaios biológicos foram conduzidos com osteoblastos da linhagem OFCOL II cultivados na superfície dos arcabouços e submetidos ou não (grupo controle) a irradiação com laser diodo InGaAIP na potência de 30 mW, nas doses de 1, 4 e 6 J/cm² e nos comprimentos de onda de 660 nm (grupos V1, V4, V6, respectivo as doses) e 780 nm (grupos I1, I4 e I6, respectivo as doses). Os efeitos do LBI na proliferação dos osteoblastos foram avaliados através do método bioquímico Alamar Blue, nos intervalos de 24, 48 e 72h, enquanto a viabilidade e a morfologia celular foram analisadas no intervalo de 72h, através do ensaio Live/Dead e da microscopia eletrônica de varredura (MEV), respectivamente. Os dados do ensaio bioquímico de Alamar Blue mostraram uma maior proliferação celular nos grupos V6 em todos os intervalos analíticos em comparação ao grupo controle (p<0,05). Outras diferenças entre o grupo controle e irradiados foram encontradas apenas nos intervalos de 48h e 72h para V1, e para o grupo IV6 em 72h. O ensaio Live/Dead revelou um aumento na viabilidade celular nos grupos trados com LBI, sendo significativamente maior no grupo V1 quando comparado ao grupo controle. A análise por MEV mostrou adequada interação dos osteoblastos aos arcabouços, com o corpo celular se espalhando ao longo do eixo da nanofibra e a presença de contatos físicos mais evidentes, através da formação de ligação por meio de filopódios e lamelipódios, nos grupos V1, V6 e I6. Em conjunto, os dados do presente trabalho mostraram que o LBI promove a bioestimulação de osteoblastos cultivados sobre nanofibras de PLA, o que aponta para o seu uso potencial nas técnicas de engenharia tecidual óssea, sobretudo no que se refere ao uso do comprimento de onda de 660 nm, a qual apresentou grupos com mais resultados significativos (AU).


Bone tissue engineering is a relevant branch of regenerative medicine and involves the development of scaffolds with composition and architecture favorable to cell integration, in addition to studying factors capable of promoting cell adhesion and proliferation, including chemical and biophysical stimuli. The study aimed to evaluate the use of low-level laser irradiation (LLLI) to promote in vitro biostimulation of osteoblastic cells cultured on polylactic acid (PLA) nanofibrous scaffolds. The scaffolds were produced by the electrospinning technique and characterized in terms of wettability, composition by Fourier transform infrared spectroscopy (FTIR), surface morphology by scanning electron microscopy (SEM), thermogravimetric characterization (TGA), differential scanning calorimetry (DSC) and crystallinity by Xray diffraction (XRD). The biological assays were conducted with osteoblasts of the OFCOL II lineage cultured on the surface of the scaffolds and submitted or not (control group) to irradiation with InGaAIP diode laser, power of 30 mW, with doses of 1, 4 and 6 J/cm² and wavelengths of 660 nm (groups V1, V4, V6, respectively doses) and 780 nm (groups I1, I4 and I6, respectively doses). The effects of LLLT from the perspective of osteoblasts were evaluated using the biochemical method Alamar Blue assay, at intervals of 24, 48 and 72h, while cell viability and morphology were observed at 72h, using the Live/Dead assay and electron microscopy. scan (SEM), respectively. The Alamar Blue assay data showed more significant cell proliferation in groups in the V6 groups at all analytical intervals compared to the control group (p<0.05). Other differences between the control and irradiated groups were found only at intervals of 48h and 72h for V1, and for group IV6 at 72h. The Live/Dead assay revealed an increase in cell viability in the groups treated with LLLT, being significantly higher in the V1 group when compared to the control group. SEM analysis showed adequate interaction between osteoblasts and scaffolds, with the cell body spreading along the nanofiber axis and the presence of more evident physical contacts, through the formation of bonds through filopodia and lamellipodia, in groups V1, V6 and I6. Together, the data from the present study observed that LLLT promotes the biostimulation of osteoblasts cultured on PLA nanofibers, which pointed to its potential use in bone tissue engineering techniques, especially with regard to the use of the wavelength of 660 nm, which presented groups with more significant results (AU).


Asunto(s)
Osteoblastos , Regeneración Ósea , Terapia por Luz de Baja Intensidad/instrumentación , Ingeniería de Tejidos , Técnicas In Vitro/métodos , Rastreo Diferencial de Calorimetría/instrumentación , Microscopía Electrónica de Rastreo/instrumentación , Espectroscopía Infrarroja por Transformada de Fourier/instrumentación
11.
Molecules ; 27(20)2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36296728

RESUMEN

To investigate the changes in chemical composition of flaxseed oil during thermal-induced oxidation and the resultant effect on thermal properties, samples with different oxidation levels were obtained by being heated at 180 °C for two hours and four hours. The oxidation degree was evaluated using peroxide value (PV), extinction coefficient at 232 nm and 268 nm (K232 and K268), and total polar compounds (TPC). Using chromatography, the fatty acid profile and triacylglycerol (TAG) profile were examined. Differential scanning calorimetry (DSC) was used to determine the crystallization and melting profiles. Thermal-induced oxidation of flaxseed oil led to a significant increase (p < 0.05) in PV, K232, K268, and TPC, but the relative content of linolenic acid (Ln) and LnLnLn reduced dramatically (p < 0.05). TPC derived from lipid degradation affected both crystallization and melting profiles. Statistical correlations showed that the onset temperature (Ton) of the crystallization curve was highly correlated with K232, TPC, and the relative content of LnLnLn (p < 0.05), whereas the offset temperature (Toff) of the melting curve was highly correlated with the relative content of most fatty acids (p < 0.05). This finding provides a new way of rapid evaluation of oxidation level and changes of chemical composition for flaxseed oils using DSC.


Asunto(s)
Aceite de Linaza , Aceites de Plantas , Rastreo Diferencial de Calorimetría , Aceite de Linaza/química , Aceites de Plantas/química , Oxidación-Reducción , Ácidos Grasos/química , Triglicéridos/química , Peróxidos , Ácidos Linolénicos
12.
Eur J Pharm Biopharm ; 179: 65-73, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36058447

RESUMEN

The study aimed to explore the size effect on the in vitro-in vivo correlation (IVIVC) in the oral absorption of andrographolide nanosuspensions (Ag-NS). Ag-NS with controllable particle sizes were prepared by ultrasonic dispersion method, and the formulation and process parameters were optimized through single factor experiments using mean particle size, polydispersity index, and stability as evaluation indicators. The morphology of Ag-NS was observed by scanning electron microscopy (SEM), and the crystalline state of the nanosuspensions was characterized by X-ray powder diffraction (XRPD) and differential scanning calorimetry (DSC). The dissolution tests were carried out with the paddle method in two different mediums simulating the pH conditions in intestinal fluid (pH 6.8) and gastric fluid (pH 1.2), respectively. The pharmacokinetic behaviors were investigated in rats after oral administration, and a deconvolution approach was introduced to determine the correlation between in vitro dissolution and in vivo absorption (IVIVC). The formulation with the use of lecithin and PEG-800 as stabilizers showed its potential in the size-controllable preparation of Ag-NS. Via altering the ultrasonication amplitude and time, three Ag-NS suspensions with three particle sizes, i.e., Ag-NS 250 (249.8 ± 1.3 nm), Ag-NS 450 (485.2 ± 3.7 nm), Ag-NS 1000 (1015 ± 36.1 nm) were prepared. Their morphological and crystal characteristics were not changed during the size reduction process, but both of their in vitro dissolution and in vivo absorption were improved. Relatively better IVIVC performance was observed with the in vitro dissolution data at pH 6.8 (r > 0.9). With the reduction of particle size, the in vivo absorption fraction was more closed to the level of the in vitro dissolution. In conclusion, the decrease in particle size would improve the dissolution and absorption of Ag-NS, and also affect their IVIVC performance. The study would facilitate the design and quality control of Ag-NS in terms of particle size and dissolution specifications.


Asunto(s)
Lecitinas , Nanopartículas , Administración Oral , Animales , Disponibilidad Biológica , Rastreo Diferencial de Calorimetría , Diterpenos , Nanopartículas/química , Tamaño de la Partícula , Ratas , Solubilidad , Suspensiones , Difracción de Rayos X
13.
Molecules ; 27(14)2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35889459

RESUMEN

Psoralen (PSO) and 5-methoxypsoralen (5-MOP) are widely used drugs in oral photochemotherapy against vitiligo and major bioactive components of root bark extract of Brosimum gaudichaudii Trécul (EBGT), previously standardized by LC-MS. However, the exceptionally low water solubility of these psoralens can cause incomplete and variable bioavailability limiting their applications and patient adherence to treatment. Therefore, the purpose of this work was to investigate the effects of 2-hydroxypropyl-ß-cyclodextrin (HP-ß-CD) inclusion complex on the solubility and jejunal permeability of PSO and 5-MOP from EBGT. Characterization of inclusion complexes were evaluated by current methods in nuclear magnetic resonance studies on aqueous solution, Fourier transform infrared spectroscopy, thermal analysis, and scanning electron microscopy in solid state. Ex vivo rat jejunal permeability was also investigated and compared for both pure psoralens and plant extract formulation over a wide HP-ß-CD concentration range (2.5 to 70 mM). Phase solubility studies of the PSO- and 5-MOP-HP-ß-CD inclusion complex showed 1:1 inclusion complex formation with small stability constants (Kc < 500 M−1). PSO and 5-MOP permeability rate decreased after adding HP-ß-CD by 6- and 4-fold for pure standards and EBGT markers, respectively. Nevertheless, the complexation with HP-ß-CD significantly improved solubility of PSO (until 10-fold) and 5-MOP (until 31-fold). As a result, the permeability drop could be overcome by solubility augmentation, implying that the HP-ß-CD inclusion complexes with PSO, 5-MOP, or EBGT can be a valuable tool for designing and developing novel oral drug product formulation containing these psoralens for the treatment of vitiligo.


Asunto(s)
Furocumarinas , Moraceae , Vitíligo , beta-Ciclodextrinas , 2-Hidroxipropil-beta-Ciclodextrina/química , Animales , Rastreo Diferencial de Calorimetría , Permeabilidad , Extractos Vegetales/farmacología , Ratas , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X , beta-Ciclodextrinas/química
14.
Food Chem ; 389: 133114, 2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-35504078

RESUMEN

In this study, the heat-induced aggregation behavior of patatin rich potato protein isolate (PPI) was investigated by reversed-phase high-pressure liquid chromatography (RP-HPLC), differential scanning calorimetry (DSC), and dynamic light scattering. It could be shown that aggregation already occurs at low temperatures, despite low degrees of unfolding. The unfolding temperature, determined by DSC, coincided with a change in the reaction kinetics, which is determined by the unfolding step below a critical temperature up to the point, where the proteins are completely unfolded. The reaction rate k as a function of the absolute temperature T is then determined by diffusion of unfolded proteins forming aggregates. This change can be visualized in the Arrhenius diagram by a change of the slope of the relationship k âˆ¼ 1/T. A change in pH from 7 to 6 shifted the critical temperature towards higher values and resulted in larger aggregate sizes, due to reduced electrostatic repulsion.


Asunto(s)
Solanum tuberosum , Rastreo Diferencial de Calorimetría , Cromatografía , Calor , Cinética , Desnaturalización Proteica , Solanum tuberosum/química , Temperatura , Termodinámica
15.
Zhongguo Zhong Yao Za Zhi ; 47(1): 103-110, 2022 Jan.
Artículo en Chino | MEDLINE | ID: mdl-35178916

RESUMEN

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.


Asunto(s)
Desecación , Tecnología , Rastreo Diferencial de Calorimetría , Composición de Medicamentos/métodos , Estabilidad de Medicamentos , Silibina , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
16.
Molecules ; 27(2)2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35056734

RESUMEN

Meloxicam (MLX) is a non-steroidal anti-inflammatory drug used to treat rheumatoid arthritis and osteoarthritis. However, its poor water solubility limits the dissolution process and influences absorption. In order to solve this problem and improve its bioavailability, we prepared it in nanocrystals with three different particle sizes to improve solubility and compare the differences between various particle sizes. The nanocrystal particle sizes were studied through dynamic light scattering (DLS) and laser scattering (LS). Transmission electron microscopy (TEM) was used to characterize the morphology of nanocrystals. The sizes of meloxicam-nanocrystals-A (MLX-NCs-A), meloxicam-nanocrystals-B (MLX-NCs-B), and meloxicam-nanocrystals-C (MLX-NCs-C) were 3.262 ± 0.016 µm, 460.2 ± 9.5 nm, and 204.9 ± 2.8 nm, respectively. Molecular simulation was used to explore the distribution and interaction energy of MLX molecules and stabilizer molecules in water. The results of differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD) proved that the crystalline state did not change in the preparation process. Transport studies of the Caco-2 cell model indicated that the cumulative degree of transport would increase as the particle size decreased. Additionally, plasma concentration-time curves showed that the AUC0-∞ of MLX-NCs-C were 3.58- and 2.92-fold greater than those of MLX-NCs-A and MLX-NCs-B, respectively. These results indicate that preparing MLX in nanocrystals can effectively improve the bioavailability, and the particle size of nanocrystals is an important factor in transmission and absorption.


Asunto(s)
Meloxicam/química , Meloxicam/farmacocinética , Nanopartículas/química , Administración Cutánea , Administración Oral , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/farmacocinética , Células CACO-2 , Rastreo Diferencial de Calorimetría , Evaluación Preclínica de Medicamentos , Dispersión Dinámica de Luz , Humanos , Masculino , Meloxicam/administración & dosificación , Microscopía Electrónica de Transmisión , Modelos Moleculares , Nanopartículas/administración & dosificación , Tamaño de la Partícula , Ratas Sprague-Dawley , Difracción de Rayos X
17.
Plant Cell Rep ; 41(2): 447-461, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35099612

RESUMEN

KEY MESSAGE: Fast-drying and cooling induce fast intracellular water loss and reduced ice-crystal formation, which may promote the formation of intracellular glasses that might improve the likelihood of wheat pollen survival. Long-term storage of pollen is important for the fertilization of spatially or temporally isolated female parents, especially in hybrid breeding. Wheat pollen is dehydration-sensitive and rapidly loses viability after shedding. To preserve wheat pollen, we hypothesized that fast-drying and cooling rates would increase the rate of intracellular water content (WC) removal, decrease intracellular ice-crystal formation, and increase viability after exposure to ultra-low temperatures. Therefore, we compared slow air-drying with fast-drying (dry air flow) and found significant correlations between pollen WC and viability (r = 0.92, P < 0.001); significant differences in WCs after specific drying times; and comparable viabilities after drying to specific WCs. Fast-drying to WCs at which ice melting events were not detected (ΔH = 0 J mg-1 DW, < 0.28 mg H2O mg-1 DW) reduced pollen viability to 1.2 ± 1.0%, but when drying to 0.39 mg H2O mg-1 DW, some viable pollen was detected (39.4 ± 17.9%). Fast cooling (150 °C min-1) of fast-dried pollen to 0.91 ± 0.11 mg H2O mg-1 DW induced less and a delay of ice-crystal formation during cryomicroscopic-video-recordings compared to slow cooling (1 °C min-1), but viability was low (4.5-6.1%) and comparable between cooling rates. Our data support that the combination of fast-drying and cooling rates may enable the survival of wheat pollen likely due to (1) a reduction of the time pollen would be exposed to drying-related deleterious biochemical changes and (2) an inhibition of intracellular ice-crystal formation, but additional research is needed to obtain higher pollen survival after cooling.


Asunto(s)
Polen/química , Polen/fisiología , Triticum , Rastreo Diferencial de Calorimetría , Frío , Microscopía por Crioelectrón , Criopreservación , Cristalización , Desecación , Liofilización , Congelación , Hielo , Polen/citología
18.
Food Chem ; 368: 130827, 2022 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-34411855

RESUMEN

Curcuminoids are known to exert diverse pharmacological effects and used in some pharmaceutical formulations. This study describes the preparation, characterization, and enhancement in the solubility and anticancer activity of a curcuminoids-rich extract (CRE) using a ternary inclusion complex system. CRE containing 88.9% w/w curcuminoids was prepared using a 'green' microwave extraction coupled with fractionation on a column of hydrophobic adsorbent resin. The ternary complex consisting of CRE, hydroxylpropyl-ß-cyclodextrin and polyvinylpyrrolidone K30 was prepared using the solvent evaporation method and thoroughly characterized using Fourier-transform infrared spectroscopy, powder X-ray diffractograms, differential scanning calorimetry and scanning electron microscopy. The ternary complex of CRE improved the water-solubility of curcuminoids (up to 70.3 µg/mL) as well as the dissolution rate when compared to those of CRE (0 µg/mL). In addition, the ternary complex exhibited significantly stronger anticancer activity against human lung adenocarcinoma (A-549), human cervical adenocarcinoma (HeLa) and human colon adenocarcinoma (HT-29) cell lines than CRE.


Asunto(s)
Diarilheptanoides , Agua , Rastreo Diferencial de Calorimetría , Humanos , Extractos Vegetales , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
19.
Curr Top Med Chem ; 22(23): 1966-1978, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34789128

RESUMEN

AIMS: The aim of this study was to simultaneously enhance the solubility and stability of bacogenins hydrolyzed bacoside rich extract by a ternary system comprised of hydrogenated soy lecithin and a third auxiliary substance, fulvic acid. METHODS: Both ternary and binary complexes were prepared using the solvent evaporation method were characterized by Fourier transform infrared technique, differential scanning calorimeter and scanning electron microscope. The entrapment efficacy in both binary and ternary system was calculated and the effect on the solubility, dissolution and stability of bacogenins was found out. Furthermore, the prepared complexes were subjected to behavioural pharmacological studies. RESULTS: FTIR, DSC, and SEM studies in totality confirmed the formation of binary and ternary complexes. Enhancement in solubility was observed, and the order of release characteristics was found to be BHFS> BHSL>BHF> BH when the dissolution studies were carried out in 40% aqueous solution of ethanol. A significant improvement in the memory and antioxidant capacity was noticed in both binary, ternary complexes and fulvic acid treatment groups. CONCLUSION: The results revealed that the ternary complex could be a promising drug delivery system to improve the oral bioavailability of the bacogenins.


Asunto(s)
Lecitinas , beta-Ciclodextrinas , Rastreo Diferencial de Calorimetría , Química Farmacéutica/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Solubilidad , Difracción de Rayos X
20.
Nat Prod Res ; 36(9): 2284-2291, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-33183085

RESUMEN

This paper presents an in-depth chemical and analytical study of a natural substance extracted from Ammodaucus leucotrichus Coss. & Dur and its derivatives after hemisynthesis. The analysis was performed using Diffusion-Ordered Spectroscopy (NMR DOSY) and Differential Scanning Calorimetry (DSC) as general methods. The results show an interesting chemical reactivity towards coumarin-derived bisnucleophiles (4-hydroxycoumarin and triacetic acid lactone), and products obtained by hemisynthesis of pyrano[4,3-b]pyrane derivatives following Knoevenagel condensation and Michael's addition on this natural substance with the use of 4-pyrolidinopyridine organobase as catalyst.


Asunto(s)
Apiaceae , Apiaceae/química , Rastreo Diferencial de Calorimetría , Catálisis , Cumarinas , Espectroscopía de Resonancia Magnética/métodos , Extractos Vegetales/química
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