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1.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(5): 754-758, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34622588

RESUMO

Objective: To explore the effect of polystyrene (PS) and PS-polyvinylpyrrolidone (PVP) electrospun materials on the adhesion ability of Porphyromonas gingivalis( P. gingivalis), a common periodontal pathogen. Methods: PS and PS-PVP electrospun materials were prepared with stainless steel needles in high-voltage electric field. The growth and adhesion of P. gingivalis on the surface of different materials were observed with scanning electron microscope (SEM). The changes in the amount of P. gingivalis biofilm formed on the surface of different materials were measured according to viable colony forming units (CFU). The effect of surface charge of the different materials on the adhesion ability of P. gingivalis was determined through changing the charge properties on the surface of the electrospun materials. Results: SEM images showed that both PS and PS-PVP can be used to form electrospun fibers with a diameter of 0.2 µm. SEM images and CFU counts of the biofilm at 24 h and 48 h showed that there was a smaller amount of P. gingivalis biofilm on the surface of the two materials ( P<0.05). After treatment with tetrabutylammonium bromide (TBAB), the surface charge of the PS-PVP electrospun material changed from being negatively charged to being positively charged, and the amount of bacterial adhesion on the surface increased significantly in comparison to that of untreated PS and PS-PVP materials ( P<0.05). Conclusion: PS and PS-PVP electrospun materials can be used to reduce the adhesion ability of P. gingivalis on the surface of different materials, and this ability may be related to the surface charge properties of the materials.


Assuntos
Porphyromonas gingivalis , Povidona , Biofilmes , Fibras na Dieta , Poliestirenos , Povidona/farmacologia
2.
J Photochem Photobiol B ; 223: 112301, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34492530

RESUMO

Prostate cancer (PCa) is the second most frequent cancer diagnosed in men worldwide. Among the common treatment options, photodynamic therapy (PDT) is being considered a promising local therapy to treat this cancer. Although PDT is an established treatment modality approved for several types of cancer, the low solubility, the reduced tumor selectivity, the absorption in the therapeutic window and the poor clearance from the body of the currently approved photosensitizers (PS) hampers its wide clinical application. In this regard, herein we synthesized three fluorinated porphyrinoid derivatives and entrapped them into polyvinylpyrrolidone (PVP) to prevent their aggregation and preserve their desirable photophysical properties under the physiological environment. In vitro studies revealed the negligible dark cytotoxicity of all PVP formulations (PS1@PVP, PS2@PVP and PS3@PVP) at the tested concentrations (5.0 to 20 µM), but also confirmed the significant photodynamic effect of PS2@PVP and PS3@PVP towards the PCa cell line PC-3, upon red light irradiation at an irradiance of 17.6 mW.cm-2. To provide insight into the underlying mechanisms of cell death under PDT treatment induced by PS2@PVP and PS3@PVP, their intracellular localization in PC-3 cells was firstly investigated by confocal microscopy. Since both PS2@PVP and PS3@PVP nanoparticles were mainly localized in mitochondria, the involvement of this organelle in PDT-induced apoptosis mediated by both formulations was further explored. Western blot analysis revealed that PDT treatment of PC-3 cells with either PS2@PVP or PS3@PVP resulted in the reduction of the expression level of the anti-apoptotic protein Bcl-2. As the photodamage to Bcl-2 after PDT with PS2@PVP and PS3@PVP was accompanied by the further activation of pro-caspase-3, we assumed that upon irradiation the photogenerated reactive oxygen species (ROS) were able to activate a caspase-dependent apoptotic response as a consequence of a post-mitochondrial event. Taken together, these findings demonstrate that among the tested fluorinated porphyrinoids, PS2@PVP and, particularly, PS3@PVP, are significantly more effective in overall PC-3 cell killing than PS1@PVP, thus highlighting their great potential as therapeutic agents for PCa.


Assuntos
Apoptose/efeitos dos fármacos , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Composição de Medicamentos , Humanos , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Nanopartículas/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/química , Porfirinas/uso terapêutico , Povidona/química , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo
3.
Int J Mol Sci ; 22(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34360872

RESUMO

Despite the numerous available treatments for cancer, many patients succumb to side effects and reoccurrence. Zinc oxide (ZnO) quantum dots (QDs) are inexpensive inorganic nanomaterials with potential applications in photodynamic therapy. To verify the photoluminescence of ZnO QDs and determine their inhibitory effect on tumors, we synthesized and characterized ZnO QDs modified with polyvinylpyrrolidone. The photoluminescent properties and reactive oxygen species levels of these ZnO/PVP QDs were also measured. Finally, in vitro and in vivo experiments were performed to test their photodynamic therapeutic effects in SW480 cancer cells and female nude mice. Our results indicate that the ZnO QDs had good photoluminescence and exerted an obvious inhibitory effect on SW480 tumor cells. These findings illustrate the potential applications of ZnO QDs in the fields of photoluminescence and photodynamic therapy.


Assuntos
Neoplasias/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes , Povidona , Pontos Quânticos/uso terapêutico , Óxido de Zinco , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Camundongos Nus , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/farmacologia , Povidona/química , Povidona/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Óxido de Zinco/química , Óxido de Zinco/farmacologia
4.
Molecules ; 26(16)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34443395

RESUMO

Recently polyphenols attracted great interest in the field of food and nutrition as well as in the pharmaceutical and cosmetics industries due to their health benefits through antioxidative behavior in the human body. However, because of the high number of compounds characterized as phenols and their structural diversity, quantification of polyphenols turns out to be a highly complex task. Although, a wide variety of analytical methods are used for the determination of total polyphenolic content, they are all found to be lacking in a variety of different tasks, such as their limits of detection and quantification, repeatability, accuracy and specificity. For this reason, a novel approach combining the advantages of solid phase purification, near infrared analysis and multivariate data analysis was investigated for the prediction of total polyphenolic content, suitable for a wide range of sample matrices. Dispersive solid phase extraction was performed and optimized using polyvinylpyrrolidone as sorbent, known to selectively bind polyphenols. Near-infrared detection of adsorbed polyphenols was carried out subsequently. Furthermore, the method was in-house validated, examining selectivity, repeatability and accuracy, working range, as well as multivariate limit of detection and limit of quantification, comparing it with two routinely used methods-namely, Folin-Ciocalteu photometric assay and Löwenthal titration. The novel established method was applied for the prediction of total polyphenolic content in tea and wine samples.


Assuntos
Polifenóis/isolamento & purificação , Povidona/química , Extração em Fase Sólida , Antioxidantes/química , Humanos , Polifenóis/química
5.
Int J Mol Sci ; 22(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34445378

RESUMO

(1) Background: Several properties of silver nanoparticles (AgNPs), such as cytotoxic, anticancer, and antimicrobial activities, have been subjects of intense research; however, important aspects such as nanoparticle aggregation are generally neglected, although a decline in colloidal stability leads to a loss of the desired biological activities. Colloidal stability is affected by pH, ionic strength, or a plethora of biomolecules that interact with AgNPs under biorelevant conditions. (2) Methods: As only a few studies have focused on the relationship between aggregation behavior and the biological properties of AgNPs, here, we have systematically evaluated this issue by completing a thorough analysis of sterically (via polyvinyl-pyrrolidone (PVP)) stabilized AgNPs that were subjected to different circumstances. We assessed ultraviolet-visible light absorption, dynamic light scattering, zeta potential measurements, in vitro cell viability, and microdilution assays to screen both colloidal stability as well as bioactivity. (3) Results: The results revealed that although PVP provided outstanding biorelevant colloidal stability, the chemical stability of AgNPs could not be maintained completely with this capping material. (4) Conclusion: These unexpected findings led to the realization that stabilizing materials have more profound importance in association with biorelevant applications of nanomaterials than just being simple colloidal stabilizers.


Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Povidona/química , Prata/farmacologia , Anti-Infecciosos/química , Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Difusão Dinâmica da Luz , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Prata/química
6.
Environ Pollut ; 289: 117812, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34333269

RESUMO

In this study, the biochar (BC) supported Fe-Cu bimetallic stabilized by PVP (Fe-Cu/PVP/BC) were prepared and utilized to enhance the nitrate (NO3-) removal and the selectivity toward nitrogen (N2). Results showed the optimum Fe:Cu:BC ratio and the dosage of the BC (pyrolysis at 700 °C) supported Fe-Cu bimetallic stabilized by polyvinylpyrrolidone (PVP) (Fe-Cu/PVP/BC700) were respectively 1:2:3 and 1 mg L-1 with the selectivity toward N2 of 31 %. This was mainly due to the synergy among Fe0, Cu0 and BC in the Fe-Cu/PVP/BC. The addition of Fe0 could reduce the NO3- through providing electron. The Cu0 and BC improved the selectivity of NO3- to N2 through forming [Cu-NO2-ads] and adjusting redox potential. The addition of Fe-Cu/PVP/BC could supply electrons for denitrification and enhance the relative abundances of Azospira and Thauera related to denitrification to improve NO3- removal. This result was further confirmed by the variations of denitrifying functional genes (narG, nirK, nirS and nosZ). This research provided an effective method to improve NO3- removal during surface water treatment in constructed wetlands (CWs) by adding Fe-Cu/PVP/BC.


Assuntos
Nitrogênio , Áreas Alagadas , Carvão Vegetal , Desnitrificação , Nitratos , Povidona , Eliminação de Resíduos Líquidos
7.
Molecules ; 26(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34279377

RESUMO

Laser radiation has been shown to be a promising approach for in situ amorphization, i.e., drug amorphization inside the final dosage form. Upon exposure to laser radiation, elevated temperatures in the compacts are obtained. At temperatures above the glass transition temperature (Tg) of the polymer, the drug dissolves into the mobile polymer. Hence, the dissolution kinetics are dependent on the viscosity of the polymer, indirectly determined by the molecular weight (Mw) of the polymer, the solubility of the drug in the polymer, the particle size of the drug and the molecular size of the drug. Using compacts containing 30 wt% of the drug celecoxib (CCX), 69.25 wt% of three different Mw of polyvinylpyrrolidone (PVP: PVP12, PVP17 or PVP25), 0.25 wt% plasmonic nanoaggregates (PNs) and 0.5 wt% lubricant, the effect of the polymer Mw on the dissolution kinetics upon exposure to laser radiation was investigated. Furthermore, the effect of the model drug on the dissolution kinetics was investigated using compacts containing 30 wt% of three different drugs (CCX, indomethacin (IND) and naproxen (NAP)), 69.25 wt% PVP12, 0.25 wt% PN and 0.5 wt% lubricant. In perfect correlation to the Noyes-Whitney equation, this study showed that the use of PVP with the lowest viscosity, i.e., the lowest Mw (here PVP12), led to the fastest rate of amorphization compared to PVP17 and PVP25. Furthermore, NAP showed the fastest rate of amorphization, followed by IND and CCX in PVP12 due to its high solubility and small molecular size.


Assuntos
Anti-Inflamatórios não Esteroides/química , Celecoxib/química , Raios Infravermelhos , Nanopartículas/química , Povidona/química , Anti-Inflamatórios não Esteroides/administração & dosagem , Celecoxib/administração & dosagem , Estabilidade de Medicamentos , Lasers , Viscosidade
8.
F1000Res ; 10: 300, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34316359

RESUMO

Background: Intravenous injection of oral opioid substitution drugs (OSD) is widespread among injecting drug users. Several OSDs contain the polymer polyvinylpyrrolidone (PVP) as an excipient. Parenterally administered PVP of high molecular weight may accumulate in tissues and organs. This phenomenon was first described in the 1950s, when PVP was utilised in medication for parenteral use. We report a case of an opioid-addicted patient with extensive PVP-deposition caused by repeated injections of OSDs. Case presentation: A 30-year-old male drug addicted patient in opioid substitution therapy (OST) was repeatedly referred to his local hospital in a poor general condition. Work-up revealed severe normocytic anaemia, renal insufficiency, pancreas insufficiency and pathological fractures. Biopsies from fractured bones, bone marrow and gastric mucosa showed extensive infiltrates of histiocytes with intracytoplasmic vacuoles. Vacuole content stained slightly bluish in hematoxylin and eosin stain, red in Congo red stain and black in periodic acid methenamine silver stain. The morphological appearance and staining properties were in accordance with the diagnosis of PVP deposition. The patient had been injecting both buprenorphine tablets and a specific methadone syrup for several years. The methadone syrup contained large amounts of high molecular weight PVP, making it the most likely cause of the deposition. His health quickly deteriorated and he died, impaired by multi-organ failure and cachexia, five years after the first diagnosis of PVP-deposition. The autopsy revealed extensive PVP-deposition in all sampled organs and tissues. Conclusions: Histological investigation and the correct identification of PVP in the biopsies led to the discovery of a severe adverse effect from long-standing misuse of a drug. The disseminated PVP deposition likely contributed to multi-organ dysfunction and cachexia with a fatal outcome. The deposited PVP likely originated from repeated injections of a certain methadone syrup.


Assuntos
Buprenorfina , Preparações Farmacêuticas , Adulto , Analgésicos Opioides , Humanos , Masculino , Povidona/efeitos adversos
9.
Int J Pharm ; 605: 120847, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34216763

RESUMO

Liquisolid systems are emerging formulation approach for poorly soluble drugs, based on adsorption/absorption of drug dispersion and obtaining free-flowing powder with good compressibility. SeDeM Expert System represents a powder processability evaluation method. It may provide additional insight into liquisolid systems critical quality attributes, but the contribution of this approach remains to be explored. The aims of this study were: pellet preparation by combination of liquisolid technology and water granulation/extrusion, evaluation of liquisolid based systems (pellets/admixtures) and investigation into the applicability of SeDeM Expert System in liquisolid systems characterization. Pellets/admixtures were prepared with microcrystalline cellulose as carrier and crospovidone/silicon dioxide as coating agent. Ibuprofen solution in polyethylene glycol 400 was used as liquid phase. After comprehensive sample characterization, experimentally obtained parameters were mathematically transformed and evaluated in the SeDeM Expert System framework. Pellets exhibited low aspect ratio and excellent flowability, despite liquid load up to 52.2%. The investigated liquisolid admixtures exhibited good flowability and faster drug dissolution than pellets. Single pellet crushing test results exhibited strong correlation with compact indentation hardness and may be used as indentation hardness predictor. SeDeM Expert System provides useful insight into liquisolid system processability and comparative evaluation and it may facilitate final solid dosage form development.


Assuntos
Sistemas Especialistas , Povidona , Liberação Controlada de Fármacos , Pós , Solubilidade , Comprimidos
10.
Molecules ; 26(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200814

RESUMO

Multi-drug resistant pathogens are a rising danger for the future of mankind. Iodine (I2) is a centuries-old microbicide, but leads to skin discoloration, irritation, and uncontrolled iodine release. Plants rich in phytochemicals have a long history in basic health care. Aloe Vera Barbadensis Miller (AV) and Salvia officinalis L. (Sage) are effectively utilized against different ailments. Previously, we investigated the antimicrobial activities of smart triiodides and iodinated AV hybrids. In this work, we combined iodine with Sage extracts and pure AV gel with polyvinylpyrrolidone (PVP) as an encapsulating and stabilizing agent. Fourier transform infrared spectroscopy (FT-IR), Ultraviolet-visible spectroscopy (UV-Vis), Surface-Enhanced Raman Spectroscopy (SERS), microstructural analysis by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-Ray-Diffraction (XRD) analysis verified the composition of AV-PVP-Sage-I2. Antimicrobial properties were investigated by disc diffusion method against 10 reference microbial strains in comparison to gentamicin and nystatin. We impregnated surgical sutures with our biohybrid and tested their inhibitory effects. AV-PVP-Sage-I2 showed excellent to intermediate antimicrobial activity in discs and sutures. The iodine within the polymeric biomaterial AV-PVP-Sage-I2 and the synergistic action of the two plant extracts enhanced the microbial inhibition. Our compound has potential for use as an antifungal agent, disinfectant and coating material on sutures to prevent surgical site infections.


Assuntos
Antibacterianos/química , Antibacterianos/síntese química , Aloe/química , Antifúngicos/química , Gentamicinas/química , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura/métodos , Nistatina/química , Extratos Vegetais/química , Povidona/química , Salvia/química , Salvia officinalis/química , Espectrometria por Raios X/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X/métodos
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 263: 120193, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34314969

RESUMO

We report a robust technique to fabricate a cost-efficient Raman substrate which is composed of polyvinylpyrrolidone (PVP) coated gold nanoparticles layer on commercial aluminum foil. The layer of metal nanoparticles on the aluminum foil, i.e., the nanoparticle-on-mirror (NPoM) structure was fabricated by spraying nanoparticle colloidal solution directly on the foil. The detection limit (LOD) of NPoM substrate is investigated by performing the SERS for Rhodamine 6G (R6G) with the concentration ranging from mM to nM without any post treatment of the substrate. The findings show that the LOD of 1 nM and maximum intensity enhancement factor of ~ 24 is accomplished. Field enhancement owing to reflection from the metallic mirror is the reason behind the signal enhancement and it would be beneficial for routine clinical applications, trace chemical detection, and disease diagnostics.


Assuntos
Nanopartículas Metálicas , Análise Espectral Raman , Análise Custo-Benefício , Ouro , Povidona
12.
AAPS PharmSciTech ; 22(5): 196, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34184149

RESUMO

In a formulation, traces of peroxides in copovidone can impact the stability of drug substances that are prone to oxidation. The present study aimed to investigate the impact of peroxides in novel Plasdone™ S630 Ultra and compare it with regular Plasdone™ S630 on the oxidative degradation of quetiapine fumarate amorphous solid dispersions prepared via hot-melt extrusion technique. The miscibility of copovidones with drug was determined using the Hansen solubility parameter, and the results indicated a miscible drug-polymer system. Melt viscosity as a function of temperature was determined for the drug-polymer physical mixture to identify the suitable hot-melt extrusion processing temperature. The binary drug and polymer (30:70 weight ratio) amorphous solid dispersions were prepared at a processing temperature of 160°C. Differential scanning calorimetry and Fourier transform infrared spectroscopy studies of amorphous solid dispersions revealed the formation of a single-phase amorphous system with intermolecular hydrogen bonding between the drug and polymer. The milled extrudates were compressed into tablets by using extragranular components and evaluated for tabletability. Stability studies of the milled extrudates and tablet formulations were performed to monitor the oxidative degradation impurity (N-oxide). The N-oxide impurity levels in the quetiapine fumarate - Plasdone™ S630 Ultra milled extrudates and tablet formulations were reduced by 2- and 3-folds, respectively, compared to those in quetiapine fumarate - Plasdone™ S630. The reduced oxidative degradation and improved hot-melt extrusion processability of Plasdone™ S630 Ultra make it a better choice for oxidation-labile drugs over Plasdone™ S630 copovidone.


Assuntos
Tecnologia de Extrusão por Fusão a Quente/métodos , Excipientes Farmacêuticos/síntese química , Povidona/síntese química , Pirrolidinas/síntese química , Fumarato de Quetiapina/síntese química , Compostos de Vinila/síntese química , Varredura Diferencial de Calorimetria/métodos , Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Temperatura Alta , Oxirredução , Excipientes Farmacêuticos/farmacocinética , Povidona/farmacocinética , Pirrolidinas/farmacocinética , Fumarato de Quetiapina/farmacocinética , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Compostos de Vinila/farmacocinética
13.
Chemosphere ; 283: 131159, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34144287

RESUMO

Silver nanoparticles (AgNPs) are among the most applied nanomaterials and have great potential to be present in the environment. Dissolved black carbon (DBC) is ubiquitous in soil as a result of large-scale application of biomass-derived black carbon as soil amendments, while its impacts on the transport of AgNPs remain unclear. In this study, two DBCs with different functional groups were prepared at 300 and 500 °C (DBC300 and DBC500), and their impacts on the transport of uncoated AgNPs (Bare-AgNP) and polyvinylpyrrolidone-coated AgNPs (PVP-AgNP) in saturated quartz sand were investigated. The transport of PVP-AgNP was much higher than Bare-AgNP under the same conditions because of the increased steric hindrance provided by PVP surface coating. The transport of two kinds of AgNPs was both enhanced by the DBCs under all the experimental conditions. DBC500 displayed a stronger enhancement effect than DBC300 on PVP-AgNP transport, but DBC300 facilitated the migration of Bare-AgNP more significantly than DBC500. The higher aromaticity and stronger hydrophobicity of DBC500 drove it to be adsorbed on the surface of PVP-AgNP, thus providing stronger steric hindrance and promotion effect on PVP-AgNP transport. However, DBC300 contained surface sulfhydryl groups, which bound with the Bare-AgNP tightly, therefore it greatly promoted Bare-AgNP transport via enhanced steric hindrance. (X)DLVO calculations indicated DBCs generally increased the energy barrier between the AgNPs and sand grains. The results shed light on the vital roles of both the properties of AgNPs and DBCs on the fate and environmental behaviors of silver nanomaterials in complex environments.


Assuntos
Nanopartículas Metálicas , Prata , Porosidade , Povidona , Prata/análise , Solo
14.
Sci Total Environ ; 790: 148105, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34091333

RESUMO

Layered black phosphorus (LBP) is regarded as a promising two-dimensional nanomaterial in various application fields. As bare LBP is unstable in humid environment, many modification methods have been developed recently. However, environmental risks of modified LBP nanomaterials are largely unknown. Herein, by sonication and in-situ surface-confined synthesis, polyvinylpyrrolidone (PVP) coated LBP (LBP/PVP), and zeolitic imidazolate framework-67 (ZIF-67) modified LBP (LBP/PVP-ZIF-67) nanomaterials were synthesized. Environmental stability and toxicity of the modified nanomaterials were compared with bare LBP. Results show that LBP/PVP-ZIF-67 exhibits excellent photothermal performance, and higher potential in electrochemical hydrogen evolution than bare LBP or LBP/PVP. Characteristic visible light absorbance at 593 nm was introduced into the nanomaterial by ZIF-67. LBP/PVP has stability in aqueous environment or cytotoxicity similar to LBP. LBP/PVP-ZIF-67 is completely stable in water within 120 h, in contrast to over 30% degradation of LBP or LBP/PVP. More than 50% of LBP in the LBP/PVP-ZIF-67 can degrade to dissolvable phosphorus in oxygenated water after 17 days, indicating the nanomaterial will not be persistent in the environment. Moreover, modification with ZIF-67 can reduce cytotoxicity of LBP. Therefore, this study develops a safe strategy to modify LBP and provides basic information for ecological risk assessment of LBP based materials.


Assuntos
Zeolitas , Fósforo , Povidona/toxicidade , Água
15.
Int J Pharm ; 605: 120800, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34133972

RESUMO

The method of 1H Nuclear Magnetic Resonance (NMR) relaxometry is applied to investigate the kinetics of the recrystallization of an active pharmaceutical ingredient (felodipine) from the amorphous phase of its physical mixture with a polymer (polyvinylpyrrolidone, PVP). Comparison of the recrystallization results obtained for amorphous felodipine and its mixtures with PVP shows that the recrystallization process of API is faster in the mixtures and depends on the content of water in the system. The free induction decay (FID) for protons that were detected are composed of three components, and the loss of water from PVP strongly influences the part characterized by the longest spin-spin lattice relaxation time. Analysis of the FID of the physical mixture indicates that the content of water does not change during the recrystalization process. The study shows that the T11H NMR relaxometry method is very useful for analysing the composition of a three-phase mixture and the recrystallization process.


Assuntos
Felodipino , Povidona , Cristalização , Cinética , Espectroscopia de Ressonância Magnética , Solubilidade
16.
Anal Chem ; 93(25): 8986-8993, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34142802

RESUMO

A new combinatory Raman subtechnique of low-frequency and micro-spatially offset Raman spectroscopy (denoted micro-SOLFRS) is demonstrated via analysis of pharmaceutical solid dosage forms. A variety of different (multilayer/multicomponent) model systems comprising celecoxib, α-lactose (the anhydrous and monohydrate form), and polyvinylpyrrolidone (PVP) were probed to test the potency of this newly developed technique to, for example, provide qualitative and quantitative information on surface and subsurface layer characteristics, including their thicknesses as well as enable monitoring of surface-driven solid-state form transformations. A simultaneous collection of low- and, the more commonly used, mid-frequency data enabled a direct comparison between these spectral regions, where the low-frequency domain (hence, micro-SOLFRS) proved superior for every respective analysis carried out herein.


Assuntos
Preparações Farmacêuticas , Análise Espectral Raman , Diagnóstico por Imagem , Formas de Dosagem , Lactose , Povidona
17.
Int J Mol Sci ; 22(11)2021 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-34071110

RESUMO

Rectal drug delivery is an effective alternative to oral and parenteral treatments. This route allows for both local and systemic drug therapy. Traditional rectal dosage formulations have historically been used for localised treatments, including laxatives, hemorrhoid therapy and antipyretics. However, this form of drug dosage often feels alien and uncomfortable to a patient, encouraging refusal. The limitations of conventional solid suppositories can be overcome by creating a thermosensitive liquid suppository. Unfortunately, there are currently only a few studies describing their use in therapy. However, recent trends indicate an increase in the development of this modern therapeutic system. This review introduces a novel rectal drug delivery system with the goal of summarising recent developments in thermosensitive liquid suppositories for analgesic, anticancer, antiemetic, antihypertensive, psychiatric, antiallergic, anaesthetic, antimalarial drugs and insulin. The report also presents the impact of various types of components and their concentration on the properties of this rectal dosage form. Further research into such formulations is certainly needed in order to meet the high demand for modern, efficient rectal gelling systems. Continued research and development in this field would undoubtedly further reveal the hidden potential of rectal drug delivery systems.


Assuntos
Administração Retal , Géis/administração & dosagem , Preparações Farmacêuticas/administração & dosagem , Supositórios/administração & dosagem , Resinas Acrílicas/química , Alginatos/química , Temperatura Corporal , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Previsões , Géis/química , Temperatura Alta , Humanos , Absorção Intestinal , Metilcelulose/química , Poloxâmero/química , Povidona/química , Supositórios/química
18.
AAPS PharmSciTech ; 22(5): 183, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34132921

RESUMO

The current study evaluated the effect of location and amount of various superdisintegrants on the properties of tablets made by twin-screw melt granulation (TSMG). Sodium-croscarmellose (CCS), crospovidone (CPV), and sodium starch glycolate (SSG) were used in various proportions intra- and extra-granular. Tabletability, compactibility, compressibility as well as friability, disintegration, and dissolution performance were assessed. The extra-granular addition resulted in the fasted disintegration and dissolution. CPV performed superior to CCS and SSG. Even if the solid fraction (SF) of the granules was lower for CPV, only a minor decrease in tabletability was observed, due to the high plastic deformation of the melt granules. The intra-granular addition of CPV resulted in a more prolonged dissolution profile, which could be correlated to a loss in porosity during tableting. The 100% intra-granular addition of the CPV resulted in a distinct decrease of the disintegration efficiency, whereas the performance of SSG was unaffected by the granulation process. CCS was not suitable to be used for the production of an immediate-release formulation, when added in total proportion into the granulation phase, but its efficiency was less impaired compared to CPV. Shortest disintegration (78 s) and dissolution (Q80: 4.2 min) was achieved with CPV extra-granular. Using CPV and CCS intra-granular resulted in increased disintegration time and Q80. However, at a higher level of appx. 500 s and appx. 15 min, only SSG showed a process and location independent disintegration and dissolution performance.


Assuntos
Carboximetilcelulose Sódica/síntese química , Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Povidona/síntese química , Carboximetilcelulose Sódica/farmacocinética , Avaliação Pré-Clínica de Medicamentos/métodos , Excipientes/síntese química , Excipientes/farmacocinética , Excipientes Farmacêuticos/síntese química , Excipientes Farmacêuticos/farmacocinética , Porosidade , Povidona/farmacocinética , Solubilidade , Comprimidos , Resistência à Tração
19.
Methods Mol Biol ; 2276: 57-66, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34060032

RESUMO

The isolation of mitochondria is gaining importance in experimental and clinical laboratory settings. Of interest, mitochondria and mitochondrial components (i.e., circular mitochondrial DNA, N-formylated peptides, cardiolipin) have been involved in several human inflammatory pathologies, such as cancer, Alzheimer's disease, Parkinson's disease, and rheumatoid arthritis. While several mitochondrial isolation methods have been previously published, these techniques are aimed at yielding mitochondria from cell types other than platelets. In addition, little information is known on the number of platelet-derived microvesicles that can contaminate the mitochondrial preparation or even the overall quality as well as functional and structural integrity of mitochondria. Here we describe a purification method, using a discontinuous Percoll gradient, yielding mitochondria of high purity and integrity from human platelets.


Assuntos
Plaquetas/ultraestrutura , Fracionamento Celular/métodos , Centrifugação com Gradiente de Concentração/métodos , DNA Mitocondrial/análise , Mitocôndrias/química , Humanos , Microscopia Eletrônica/métodos , Mitocôndrias/ultraestrutura , Plasma Rico em Plaquetas , Povidona/química , Dióxido de Silício/química
20.
Int J Biol Macromol ; 183: 600-613, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33932424

RESUMO

pH-sensitive drug delivery systems based on amphiphilic copolymers constitute a promising strategy to overcome some challenges to cancer treatment. In the present study, quercetin-loaded chitosan/polyvinylpyrrolidone/γ-Alumina nanocomposite was fabricated through a double oil in water emulsification method for the first time. γ-Alumina was incorporated to improve the drug loading efficiency and release behavior of polyvinylpyrrolidone and chitosan copolymeric hydrogel. γ-Alumina nanoparticles were obtained by the sol-gel method with a nanoporous structure, high surface area, and hydroxyl-rich surface. Quercetin, a natural anticancer agent, was loaded into the nanocomposite as a drug model. XRD and FTIR analyses confirmed the crystalline properties and chemical bonding of the prepared nanocomposite. The size of drug-loaded nanocomposites was 141 nm with monodisperse particle distribution, having a spherical shape approved by DLS analysis and FE-SEM, respectively. Incorporating γ-Alumina nanoparticles improved the encapsulation efficiency up to 95%. Besides, swelling study and the quercetin release profile demonstrated that γ-Alumina ameliorated pH sensitivity of nanocomposite and a targeted controlled release was obtained. Various release kinetic models were applied to the experimental release data to study the mechanism of drug release. Through MTT assay and flow cytometry, the quercetin-loaded nanocomposite showed significant cytotoxicity on MCF-7 breast cancer cells. Also, the enhanced apoptotic cell death confirmed the anticancer activity of γ-Alumina. These results suggest that the chitosan/polyvinylpyrrolidone/γ-Alumina nanocomposite is a novel pH-sensitive drug delivery system for anticancer applications.


Assuntos
Óxido de Alumínio/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Quitosana/síntese química , Portadores de Fármacos , Nanoporos , Povidona/síntese química , Quercetina/farmacologia , Óxido de Alumínio/química , Antineoplásicos Fitogênicos/química , Neoplasias da Mama/patologia , Quitosana/análogos & derivados , Preparações de Ação Retardada , Composição de Medicamentos , Liberação Controlada de Fármacos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Cinética , Células MCF-7 , Povidona/análogos & derivados , Quercetina/química
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