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1.
Environ Monit Assess ; 193(12): 824, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34792658

RESUMO

Globally, the production of zinc oxide nanoparticles (ZnO NPs) increased due to its wide applications including cosmetics, paints etc., and gets accumulated in the environment during their production, use or end-of-life. The toxic effects of the NPs vary with the presence of various surface modification agents. In the current report, toxic effect of bare and capped ZnO NPs with polymeric surface modifying agent including polyvinyl alcohol (PVA), polyethylene glycol (PEG) and polyvinylpyrrolidone (PVP) is studied against adult as well as embryonic zebra fish. The surface capped NPs showed great variation in toxicity levels. It was observed that ZnO-PVA showed highly reduced toxic effects relative to ZnO-PEG and ZnO-PVP. Further, various environmental agents including humic acid can also have an impact on NPs toxicity. ZnO particles showed increased toxic effect in humic acid presence. The uptake of ZnO particles by D. rerio was high in the order of PVP-, PEG- and PVA- followed by bare-ZnO. The current investigation found that ZnO NPs dissolution and uptake are the major factors which cause the toxicity against adult as well as embryonic zebra fishes respectively.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Animais , Monitoramento Ambiental , Nanopartículas Metálicas/toxicidade , Nanopartículas/toxicidade , Polietilenoglicóis/toxicidade , Álcool de Polivinil/toxicidade , Povidona/toxicidade , Peixe-Zebra , Óxido de Zinco/toxicidade
2.
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
3.
Part Fibre Toxicol ; 18(1): 38, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-34663357

RESUMO

BACKGROUND: Silver nanoparticles (AgNPs) are widely used in biomedicine due to their strong antimicrobial, antifungal, and antiviral activities. Concerns about their possible negative impacts on human and environmental health directed many researchers towards the assessment of the safety and toxicity of AgNPs in both in vitro and in vivo settings. A growing body of scientific information confirms that the biodistribution of AgNPs and their toxic effects vary depending on the particle size, coating, and dose as well as on the route of administration and duration of exposure. This study aimed to clarify the sex-related differences in the outcomes of oral 28 days repeated dose exposure to AgNPs. METHODS: Wistar rats of both sexes were gavaged daily using low doses (0.1 and 1 mg Ag/kg b.w.) of polyvinylpyrrolidone (PVP)-coated small-sized (10 nm) AgNPs. After exposure, blood and organs of all rats were analysed through biodistribution and accumulation of Ag, whereas the state of the liver and kidneys was evaluated by the levels of reactive oxygen species (ROS) and glutathione (GSH), catalase (CAT) activity, superoxide dismutase (SOD) and glutathione peroxidase (GPx), expression of metallothionein (Mt) genes and levels of Mt proteins. RESULTS: In all animals, changes in oxidative stress markers and blood parameters were observed indicating the toxicity of AgNPs applied orally even at low doses. Sex-related differences were noticed in all assessed parameters. While female rats eliminated AgNPs from the liver and kidneys more efficiently than males when treated with low doses, the opposite was observed for animals treated with higher doses of AgNPs. Female Wistar rats exposed to 1 mg PVP-coated AgNPs/kg b.w. accumulated two to three times more silver in the blood, liver, kidney and hearth than males, while the accumulation in most organs of digestive tract was more than ten times higher compared to males. Oxidative stress responses in the organs of males, except the liver of males treated with high doses, were less intense than in the organs of females. However, both Mt genes and Mt protein expression were significantly reduced after treatment in the liver and kidneys of males, while they remained unchanged in females. CONCLUSIONS: Observed toxicity effects of AgNPs in Wistar rats revealed sex-related differences in response to an oral 28 days repeated exposure.


Assuntos
Nanopartículas Metálicas , Povidona , Animais , Feminino , Masculino , Nanopartículas Metálicas/toxicidade , Polivinil , Povidona/toxicidade , Ratos , Ratos Wistar , Prata/toxicidade , Distribuição Tecidual
4.
Nat Commun ; 12(1): 5922, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34635666

RESUMO

Death from acute hemorrhage is a major problem in military conflicts, traffic accidents, and surgical procedures, et al. Achieving rapid effective hemostasis for pre-hospital care is essential to save lives in massive bleeding. An ideal hemostasis material should have those features such as safe, efficient, convenient, economical, which remains challenging and most of them cannot be achieved at the same time. In this work, we report a rapid effective nanoclay-based hemostatic membranes with nanoclay particles incorporate into polyvinylpyrrolidone (PVP) electrospun fibers. The nanoclay electrospun membrane (NEM) with 60 wt% kaolinite (KEM1.5) shows better and faster hemostatic performance in vitro and in vivo with good biocompatibility compared with most other NEMs and clay-based hemostats, benefiting from its enriched hemostatic functional sites, robust fluffy framework, and hydrophilic surface. The robust hemostatic bandages based on nanoclay electrospun membrane is an effective candidate hemostat in practical application.


Assuntos
Bandagens , Hemorragia/tratamento farmacológico , Hemostáticos/farmacologia , Caulim/farmacologia , Nanoestruturas/química , Ferida Cirúrgica/tratamento farmacológico , Animais , Argila/química , Modelos Animais de Doenças , Hemorragia/sangue , Hemorragia/patologia , Hemostasia/efeitos dos fármacos , Hemostáticos/química , Humanos , Caulim/química , Fígado/irrigação sanguínea , Fígado/efeitos dos fármacos , Fígado/lesões , Masculino , Nanoestruturas/administração & dosagem , Nanoestruturas/ultraestrutura , Povidona/química , Povidona/farmacologia , Ratos , Ratos Sprague-Dawley , Baço/irrigação sanguínea , Baço/efeitos dos fármacos , Baço/lesões , Ferida Cirúrgica/sangue , Ferida Cirúrgica/patologia
5.
Eur J Pharm Sci ; 167: 106014, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34644598

RESUMO

Supersaturation as a formulation principle relates to the aqueous solubility of poorly soluble drugs in solution . However, supersaturation state of drugs tends to crystallize because of its thermodynamic instability thereby compromising the solubility and biopharmaceutical performance of drugs. The present study aims to investigate the supersaturation potential of albendazole (ABZ) and its precipitation via nucleation and crystal growth. We hypothesized the use of polymers will avoid ABZ precipitation by interacting with drug molecules. The drug polymer interactions are characterized using conventional methods of Fourier transform infrared (FTIR), Nuclear magnetic resonance (NMR) and Polarized light microscopy (PLM). We have used a novel approach of sum frequency generation (SFG) vibrational spectroscopic in exploring the drug polymer interactions at air-water interface. Recently we have reported the SFG for e rifaximin-polymer interactions (Singh et al., 2021). The supersaturation assay, saturation solubility studies and nucleation induction time analysis revealed polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP K30) as effective precipitation inhibitors thereby enhancing the ABZ equilibrium solubility and in vitro supersaturation maintenance of ABZ. Further, modification in the solid state of ABZ has confirmed the influence of polymers on its precipitation behaviour. We conclude that PVA and PVP K30 act as nucleation and crystal growth inhibitor, respectively for the precipitation inhibition of ABZ.


Assuntos
Preparações Farmacêuticas , Polímeros , Albendazol , Povidona , Solubilidade
6.
Int J Pharm ; 609: 121157, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34626795

RESUMO

Microwave-induced in situ amorphization is an emerging technology to tackle the persistent stability issue of amorphous solid dispersions (ASDs) during manufacture and storage. The aim of this study was to introduce new effective polymeric carriers with diverse properties to microwave-induced in situ amorphization and to better understand their functions in relation to the final dissolution performance of microwaved tablets. Tablets composed of indomethacin (IND) and different polymers were compacted, stored at 75% relative humidity for at least 1 week and microwaved at 1000 W to induce amorphization. A series of polymers, polyvinylpyrrolidone/vinyl acetate copolymers (PVP/VA) of different monomer weight ratios displaying varyingproperties in functional groupratio, hygroscopicity, molecular weight (Mw), and glass transition temperature (Tg) of the polymer were used as model carriers. The results suggested that more than 90% of IND was amorphized after 20 mins microwaving in all 20% (w/w) drug loaded tablets except for IND:PVAc tablets presenting approx. 36% residual crystallinity. Among them, tablets composed of PVP/VA I-335 and PVP K30 achieved complete in situ amorphization upon microwaving. Further analysis indicated that the influencing factors, polymer Mw and Tg of moisture-plasticized polymer, played a major role in microwave-induced in situ amorphization. In in vitro dissolution study, ASDs containing PVP/VA I-535 with moderate hydrophilicity and 0.96 ± 1.92% IND residual crystallinity showed the most rapid and complete drug release among all formulations, presenting the most promising dissolution performance. Further study on the chemical stability of such formulation showed a statistically insignificant decrease of drug content after pre-conditioning and microwaving (P = 0.288 > 0.05).


Assuntos
Micro-Ondas , Polímeros , Celecoxib , Estabilidade de Medicamentos , Indometacina , Povidona , Solubilidade
7.
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
8.
Eye Contact Lens ; 47(12): 651-654, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34570021

RESUMO

OBJECTIVES: To assess whether meibomian glands and ocular surface parameters are affected by repeated topical povidone-iodine and antibiotic applications in patients with repeated intravitreal injections. METHODS: Forty-five patients with at least three previous intravitreal injections and 28 healthy controls were included in the study. In the injection group, 21 patients had age-related macular degeneration and 24 patients had diabetic macular edema. For each participant, infrared meibography for the upper and lower eyelids and noninvasive tear break-up time calculation were performed with a corneal topographer. Fluorescein tear break-up time and ocular surface disease index (OSDI) scores were also obtained. Noninvasive tear break-up time, fluorescein tear break-up time, and OSDI scores were recorded for each participant and compared between the injection and control groups. These parameters were also compared as a subgroup analysis between patients with age-related macular degeneration (AMD) and diabetic macular edema (DME). RESULTS: Upper lid meibomian gland loss, lower lid meibomian gland loss ratios, and OSDI scores were significantly higher in the intravitreal injection group compared with the control group (P=0.004, P<0.001, P<0.001, respectively). Fluorescein tear break-up time and noninvasive tear break-up time were significantly lower in the intravitreal injection group compared with the control group (P<0.001, P<0.001). There was no significant difference between the AMD and DME groups for these parameters. CONCLUSION: This study showed for the first time that meibomian gland losses were significantly increased by repeated povidone-iodine and antibiotic applications in patients with repeated intravitreal injections. Ocular surface parameters were altered with higher ocular surface symptoms in those patients.


Assuntos
Retinopatia Diabética , Síndromes do Olho Seco , Edema Macular , Antibacterianos , Humanos , Injeções Intravítreas , Edema Macular/tratamento farmacológico , Edema Macular/etiologia , Glândulas Tarsais , Povidona , Povidona-Iodo , Lágrimas
9.
AAPS PharmSciTech ; 22(7): 235, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34498147

RESUMO

Molecular dispersions are a highly effective method of increasing bioavailability for a poorly soluble active pharmaceutical ingredient (API) and can be prepared on a large scale by hot melt extrusion (HME). Processing thermally labile active pharmaceutical ingredients (APIs) via HME is generally more difficult, with operating temperatures limited to below that of the API melting point. API melting is considered essential to facilitate the formation of a fully homogeneous amorphous system. Processing below the melting point renders the system much more susceptible to residual crystalline content; hence, HME is not suitable for APIs which degrade upon melting. In the following work, meloxicam (MEL) was used as a model API, possessing properties of high melting temperature and thermal lability. In this proof of concept work, a modified HME method, termed solvent-assisted HME, was used to overcome this issue and prepare an amorphous solid dispersion using HME, wherein a solvent was incorporated in the formulation blend during extrusion and removed post-processing. Formulations containing 10%wt meloxicam (MEL) and 90%wt polyvinylpyrrolidone vinyl acetate (PVPVA) copolymer were extruded using a twin-screw extruder at temperatures below the melting point of MEL. Dimethylformamide (DMF) solvent was added directly into the extruder barrel through a liquid addition port, resulting in extrudate products having a higher conversion of API to the amorphous form. The incorporation of solvent allowed a significant reduction in processing temperatures due to its increased mobility, while also driving the conversion of the API to its amorphous form. The solvent was successfully reduced through a secondary drying step using a vacuum oven. This advancement has demonstrated the potential for thermally labile APIs to be processed via HME expanding the applications of this technology.


Assuntos
Química Farmacêutica , Tecnologia de Extrusão por Fusão a Quente , Composição de Medicamentos , Temperatura Alta , Povidona , Solubilidade , Solventes
10.
Molecules ; 26(18)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34577104

RESUMO

During forced degradation, the intrinsic stability of active pharmaceutical ingredients (APIs) could be determined and possible impurities that would occur during the shelf life of the drug substance or the drug product could be estimated. Vildagliptin belongs to relatively new oral antidiabetic drugs named gliptins, inhibiting dipeptidyl peptidase 4 (DPP-4) and prolonging the activities of the endogenous incretin hormones. At the same time, some gliptins were shown as prone to degradation under specific pH and temperature conditions, as well as in the presence of some reactive excipients. Thus, forced degradation of vildagliptin was performed at high temperature in extreme pH and oxidative conditions. Then, selective LC-UV was used for quantitative determination of non-degraded vildagliptin in the presence of its degradation products and for degradation kinetics. Finally, identification of degradation products of vildagliptin was performed using an UHPLC-DAD-MS with positive ESI. Stability of vildagliptin was also examined in the presence of pharmaceutical excipients, using mid-IR and NIR with principal component analysis (PCA). At 70 °C almost complete disintegration of vildagliptin occurred in acidic, basic, and oxidative media. What is more, high degradation of vildagliptin following the pseudo first-order kinetics was observed at room temperature with calculated k values 4.76 × 10-4 s-1, 3.11 × 10-4 s-1, and 1.73 × 10-4 s-1 for oxidative, basic and acidic conditions, respectively. Next, new degradation products of vildagliptin were detected using UHPLC-DAD-MS and their molecular structures were proposed. Three degradants were formed under basic and acidic conditions, and were identified as [(3-hydroxytricyclo- [3.3.1.13,7]decan-1-yl)amino]acetic acid, 1-{[(3-hydroxytricyclo[3.3.1.13,7]decan-1-yl)amino]acetyl}-pyrrolidine-2-carboxylic acid and its O-methyl ester. The fourth degradant was formed in basic, acidic, and oxidative conditions, and was identified as 1-{[(3-hydroxytricyclo[3.3.1.13,7]-decan-1-yl)amino]acetyl}pyrrolidine-2-carboxamide. When stability of vildagliptin was examined in the presence of four excipients under high temperature and humidity, a visible impact of lactose, mannitol, magnesium stearate, and polyvinylpirrolidone was observed, affecting-NH- and CO groups of the drug. The obtained results (kinetic parameters, interactions with excipients) may serve pharmaceutical industry to prevent chemical changes in final pharmaceutical products containing vildagliptin. Other results (e.g., identification of new degradation products) may serve as a starting point for qualifying new degradants of vildagliptin as it is related to substances in pharmacopoeias.


Assuntos
Cromatografia Líquida/métodos , Estabilidade de Medicamentos , Hipoglicemiantes/química , Espectrofotometria Infravermelho/métodos , Vildagliptina/química , Inibidores da Dipeptidil Peptidase IV/química , Excipientes/química , Temperatura Alta , Umidade , Concentração de Íons de Hidrogênio , Cinética , Lactose/química , Manitol/química , Espectrometria de Massas , Oxirredução , Povidona/análogos & derivados , Povidona/química , Análise de Componente Principal , Espectrofotometria Ultravioleta , Ácidos Esteáricos/química
11.
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
12.
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
13.
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
14.
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
15.
PLoS One ; 16(8): e0249075, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34339440

RESUMO

Liquisolid compact is a novel dosage form in which a liquid medication (liquid drug, drug solution/dispersion in non-volatile solvent/solvent system) is converted to a dry, free flowing powder and compressed. Objective of the study was to elucidate the effect of carrier material on release characteristics of clopidogrel from liquisolid compacts. Different formulations of liquisolid compacts were developed using microcrystalline cellulose, starch maize, polyvinyl pyrollidone and hydroxypropyl methylcellulose as carrier material in three concentrations (40, 30 and 20%, w/w). Liquid vehicle was selected on the basis of solubility of clopidogrel. Colloidal silicondioxide was used as coating material and ratio of carrier to coating material was kept 10. A control formulation comprised of microcrystalline cellulose (diluents), tabletose-80 (diluents), primojel (disintegrant) and magnesium stearate (lubricant) was prepared by direct compression technique and was used for comparison. All the formulations were evaluated at pre and post compression level. Acid solubility profile showed higher solubility in HCl buffer pH2 (296.89±3.49 µg/mL). Mixture of propylene glycol and water (2:1, v/v) was selected as liquid vehicle. Drug content was in the range of 99-101% of the claimed quantity. All the formulations showed better mechanical strength and their friability was within the official limits (<1%). Microcrystalline cellulose and starch maize resulted in faster drug release while polyvinyl pyrollidone and HPMC resulted in sustaining drug release by gel formation. It is concluded from results that both fast release and sustained release of clopidogrel can be achieved by proper selection of carrier material.


Assuntos
Clopidogrel/administração & dosagem , Portadores de Fármacos/farmacocinética , Celulose/farmacocinética , Clopidogrel/química , Clopidogrel/farmacocinética , Derivados da Hipromelose/farmacocinética , Veículos Farmacêuticos/farmacocinética , Povidona/farmacocinética , Solubilidade , Amido/farmacocinética
16.
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
17.
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
18.
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
19.
Artigo em Inglês | MEDLINE | ID: mdl-34246171

RESUMO

During the winemaking process, fining materials derived from milk and egg products are traditionally used to remove undesirable substances to reduce bitterness and astringency. The possible residues of allergens in treated wine may pose a potential risk for allergy patients. In this study, we developed a method for the simultaneous quantification of eight allergens (αS1-casein, αS2-casein, ß-casein, κ-casein, ß-lactoglobulin, lysozyme, ovalbumin and ovotransferrin) in red wine by ultrahigh-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS). The sample was extracted with polyvinylpolypyrrolidone (PVPP) solution, following trypsin digestion and peptide-level purification by solid-phase extraction (SPE). A strategy based on standard addition was used for the accurate quantification of the target allergens in wine products. The limits of detection (LODs) were shown to be 0.003-0.015 µg/mL for milk allergens and 0.1 µg/mL for egg allergens. This economical and reliable method would be appropriate for routine analysis and further allergen label management for red wine.


Assuntos
Alérgenos , Cromatografia Líquida de Alta Pressão/métodos , Povidona/análogos & derivados , Extração em Fase Sólida/métodos , Vinho/análise , Alérgenos/análise , Alérgenos/isolamento & purificação , Limite de Detecção , Modelos Lineares , Povidona/química , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
20.
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
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