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BACKGROUND: Neglected Tropical Diseases (NTD) are chronic infectious conditions that primarily affect marginalized populations. The chemotherapeutic arsenal available for treating NTD is limited and outdated, which poses a challenge in controlling and eradicating these diseases. This is exacerbated by the pharmaceutical industry's lack of interest in funding the development of new therapeutic alternatives. In addition, a considerable number of drugs used in NTD therapy have low aqueous solubility. To address this issue, solubility enhancement strategies, such as the use of inclusion complexes with cyclodextrins (CD) can be employed. OBJECTIVE: Therefore, this systematic review aims to present the application of CD in complexing with drugs and chemotherapeutic compounds used in the therapy of some of the most prevalent NTD worldwide and how these complexes can enhance the treatment of these diseases. METHODS: Two bibliographic databases, Science Direct and PubMed, were used to conduct the search. The selection of studies and the writing of this systematic review followed the criteria outlined by the PRISMA guidelines. RESULTS: From a total of 978 articles, 23 were selected after applying the exclusion criteria. All the studies selected were consistent with the use of CD as a strategy to increase the solubility of therapeutic agents used in NTD. CONCLUSION: The results indicate that CD can enhance the solubility of chemotherapeutic agents for the treatment of Neglected Tropical Diseases (NTD). This review presents data that clearly highlights the potential use of CD in the development of new treatments for neglected tropical diseases. It can assist in the formulation of future treatments that are more effective and safer.
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Schistosomiasis is a parasitic disease that can be asymptomatic, but it can progress and cause serious damage, such as hospitalization and death. This work aimed to characterize and carry out the in vivo pharmacological test of the dry extract of Morinda citrifolia and obtain a pharmaceutical dosage form based on this extract for the treatment of schistosomiasis. The aqueous extract was characterized based on the evaluation of pH, dry residue and density. The aqueous extract was dried through the freeze-drying process. The obtained dry extract was characterized through phytochemical screening, rheological analysis, acute toxicity and in vivo pharmacology. Additionally, the pre-formulation development of a pharmaceutical dosage form was pursued with the dry extract. Through the HPLC chromatogram, characteristic rutin peaks were identified. The rheological behavior of the dry extract did not show good characteristics. Acute toxicity, at a dose of 2000 mg/kg, showed excitatory activity in the central and autonomous nervous system. The in vivo pharmacological test of the dry extract showed that, at a dose of 400 mg/kg, it was possible to reduce 67.5% of the total adult worms, 66% of female worms and 60% of the number of eggs. The pharmaceutical dosage form obtained was an oral solution that was clear, transparent, without the presence of lumps and precipitates, having a density of 1.1276 g mL-1 and pH of 5.92. The results obtained will provide parameters for the production of suitable pharmaceutical formulations, as well as for the quality control of products based on M. citrifolia, with promising schistosomicidal activity.
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Morinda , Esquistosomiasis , Animales , Extractos Vegetales/uso terapéutico , Extractos Vegetales/toxicidad , Morinda/química , Composición de Medicamentos , Agua , Frutas/químicaRESUMEN
BACKGROUND: ß-lapachone (ß-lap) is a naphthoquinone widely found in species of vegetables. However, its poor aqueous solubility limits its systemic administration and clinical applications in vivo. To overcome this limitation, several studies have been carried out in order to investigate techniques that can enhance the solubility and dissolution rate of ß-lap, such as the use of inclusion complexes with cyclodextrin. PURPOSE: To evaluate the in vivo effect of ß-lap complexed in methyl-ß-cyclodextrin (MßCD) on the evolutionary stages of Schistosoma mansoni in a murine model. METHODS: The development and characterization of the physicochemical properties of the inclusion complex of ß-lap in ß-lap:MßCD was prepared by solubility and dissolution tests, FTIR, DSC, X-RD and SEM. The mice were infected and subsequently treated with ß-lap:MßCD orally with 50 mg/kg/day and 100 mg/kg/day for 5 consecutive days, starting therapy on the 1st (skin schistosomula), 14th (pulmonary schistosomula), 28th (young worms) and 45th (adult worms) days after infection. Control groups were also formed; one infected untreated, treated with MßCD, and the other treated with PZQ. RESULTS: The loss of the crystalline form of ß-lap in the ß-lap:MßCD complex obtained by spray drying was proven through physical-chemical characterization analyses. ß-lap:MßCD caused reduction in the number of worms of the 33.56%, 35.7%, 35.45% and 36.45%, when the dose was at 50 mg/kg, and 65.00%, 60.34%, 52.72% and 65.01%, in the dose 100 mg/kg; when treatment was started in the 1st, 14th, 28th and 45th days after infection, respectively. It was also possible to observe a significant reduction in the number of immature eggs and an increase in the number of ripe and dead eggs and, consequently, a reduction in the damage caused by the egg antigens to the host tissue, where we attributed the reduction in the average diameter of the granulomas to the ß-lap. CONCLUSION: The dissolved content of ß-lap:MßCD by spray drying reached almost 100%, serving for future formulations and delineation of the mechanisms of action of ß-lap against S. mansoni.
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Naftoquinonas , Schistosoma mansoni , Animales , Ratones , Secado por Pulverización , Modelos Animales de Enfermedad , Naftoquinonas/farmacologíaRESUMEN
BACKGROUND: The oral route is the most frequently used and the most convenient route of drug administration since it has several advantages, such as ease of use, patient compliance, and better costeffectiveness. However, physicochemical and biopharmaceutical limitations of various active pharmaceutical ingredients (API) hinder suitability for this route, including degradation in the gastrointestinal tract, low intestinal permeability, and low bioavailability. To overcome these problems, while maintaining therapeutic efficacy, polymeric nanoparticles have attracted considerable attention for their ability to increase drug solubility, promote the controlled release, and improve stability. In addition, the functionalization of nanocarriers can increase uptake and accumulation at the target site of action, and intestinal absorption, making it possible to obtain more viable, safe and efficient treatments for oral administration. OBJECTIVE: This systematic review aimed to seek recent advances in the literature on the use of polymeric nanoparticles functionalization to increase intestinal permeability of APIs that are intended for oral administration. METHODS: Two bibliographic databases were consulted (PubMed and ScienceDirect). The selected publications and the writing of this systematic review were based on the guidelines mentioned in the PRISMA statement. RESULTS: Out of a total of 3036 studies, 22 studies were included in this article based on our eligibility criteria. The results were consistent for the application of nanoparticle functionalization to increase intestinal permeability. CONCLUSION: The functionalized polymeric nanoparticles can be considered as carrier systems that improve the intestinal permeability and bioavailability of APIs, with the potential to result, in the future, in the development of oral medicines.
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Productos Biológicos , Nanopartículas , Administración Oral , Disponibilidad Biológica , Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Humanos , Permeabilidad , Preparaciones Farmacéuticas , Polímeros/metabolismoRESUMEN
BACKGROUND: Albendazole (ABZ) is the drug of choice for the treatment of a variety of human and veterinary parasites. However, it has low aqueous solubility and low bioavailability. Cyclodextrins (CD) are pharmaceutical excipients with the ability to modulate the solubilization property of hydrophobic molecules. OBJECTIVE: The aim of the study was to analyze through in vitro and in silico studies (Autodock Vina software and CycloMolder platform) the formation of inclusion complexes between ABZ, ß-cyclodextrin (ß-CD) and its derivatives Methyl-ß-cyclodextrin (M-ß-CD) and Hydroxypropyl-ß-cyclodextrin (HP-ß-CD). METHODS: The most stable inclusion complexes were produced by the kneading method and characterized by Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), X-Ray Diffraction (XRD), determination of the ABZ content and in vitro dissolution profile. RESULTS: Molecular modeling revealed that inclusion complexes between HP-ß-CD:ABZ (in the proportion 1:1 and 2:1) presented the lowest formation energy and the highest number of intermolecular interactions, showing that the use of more cyclodextrins does not generate gains in the stability of the complex. On the characterization tests, the complexes experimentally obtained by the kneading method demonstrated highly suggestive parameters, including ABZ in HP-ß-CD in both molar proportions, suppression of bands in the infrared spectrum, displacement of the drug's melting temperature in DSC, crystallinity halos instead of the characteristic peaks of ABZ crystals in the XRD and a release of more than 80% of ABZ in less than 5 minutes, dissolution efficiency of up to 92%. CONCLUSION: In silico studies provided a rational selection of the appropriate complexes of cyclodextrin, enabling the elaboration of more targeted complexes, decreasing time and costs for elaboration of new formulations, thereby increasing the oral biodisponibility of ABZ.
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Albendazol , Ciclodextrinas , 2-Hidroxipropil-beta-Ciclodextrina , Albendazol/química , Rastreo Diferencial de Calorimetría , Ciclodextrinas/química , Humanos , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Difracción de Rayos XRESUMEN
In this work, we investigated in vitro the antioxidant, cytotoxic and anti-leishmanial activities of a lignin extracted from the leaves of Morinda citrifolia. Initially, an analysis of the composition of the sheets was performed, then the lignin was obtained by alkaline delignification and characterized by different techniques: elemental analysis, FT-R, UV-vis, HSQC-NMR, thermal analysis, Py-GC/MS and by GPC. The results showed that the leaves had in their composition cellulose (31.29%), hemicellulose (25.01%), lignin (18.34%), extractives (14.39%) and ash (10.03%). The lignin extraction yield was 89.8%. The lignin obtained is of the GSH type with the following contents 79.39%, 13.58% and 7.03% respectively. Furthermore, it is low molecular weight and thermally stable. It had a phenolic content of 93.3 mg GAE/g and low antioxidant activity. In macrophage cytotoxicity assays, it presented a CC50 of 31.0 µg/mL, showing less toxicity than amphotericin B. In assays against the promastigote forms of Leishmania amazonensis, lignin presented an IC50 of 29.56 µg/mL, a less effective concentration than amphotericin B (IC50 = 0.14 µg/mL). However, it was able to promote inhibition of the parasites, a fact confirmed by structural changes. These findings reinforce that M. citrifolia lignin is a promising macromolecule for use as an antiparasitic and antioxidant agent.
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Antioxidantes , Antiprotozoarios , Citotoxinas , Leishmania/crecimiento & desarrollo , Lignina , Morinda/química , Hojas de la Planta/química , Animales , Antioxidantes/química , Antioxidantes/farmacología , Antiprotozoarios/química , Antiprotozoarios/farmacología , Línea Celular , Citotoxinas/química , Citotoxinas/farmacología , Evaluación Preclínica de Medicamentos , Lignina/química , Lignina/farmacología , RatonesRESUMEN
Layered Double Hydroxides (LDH) have received great attention in the development of drug carrier systems. LDHs have become intelligent excipients of high technological potential for the pharmaceutical industry due to their ability to intercalate biomaterials in the interlayer region, adsorb substances on its vast surface area, have flexible structure, swelling properties, high chemical and thermal stability, modulate drug release, have high biocompatibility and be easily synthesized. This article, using typical examples, mainly addresses the systems formed between LDHs and antimicrobial, antineoplastic and anti-inflammatory agents, which constitute the main pharmacological classes of wide interest due to the problems encountered with low solubility, control in administration, stability in body fluids and toxicity, among others. Additionally, the article also reports on the recent development of ternary or quaternary (multicomponent systems) compounds based on LDH, bringing the advantages of targeted therapy, improving the aqueous stability of nanohybrids and the performance of these inorganic carriers.
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Antineoplásicos , Excipientes , Portadores de Fármacos , Liberación de Fármacos , HidróxidosRESUMEN
BACKGROUND: Inflammation is an essential response provided by the immune system, ensuring the survival during microbial infection, tissue injury and other noxious conditions. However, prolonged inflammatory processes are often associated with severe side effects on health. OBJECTIVE: This systematic review aimed to provide the evidence in the literature of the preclinical and human anti-inflammatory activity of gallium compounds from 2000 to 2019 focused on elucidating the mechanisms involved in the inflammatory process. METHODS: Seven bibliographical databases were consulted (PubMed, Medline, ScienceDirect, Scopus, Springer, Web of Science, and EBSCOhost). The selection of appropriate publications and writing of this systematic review were based on the guidelines mentioned in the PRISMA statement. Moreover, the assessment of the methodological quality of the selected studies was also performed. RESULTS: From a total of 3018 studies, 16 studies were included in this paper based on our eligibility criteria, which showed promising and consistent results. CONCLUSION: Further research concerning specific inflammatory conditions is required.
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Antiinflamatorios , Galio , Antiinflamatorios/farmacología , Galio/farmacología , Humanos , Inflamación/tratamiento farmacológicoRESUMEN
The measures currently used to minimize the spread of arboviruses, comprising dengue, Chikungunya, and Zika virus, involve controlling the size of population of the mosquito Aedes aegypti. However, the search for formulations containing new insecticides is gaining pace due to reports of mosquito populations showing resistance to commonly used compounds. In this study, tablets containing a protein fraction of Moringa oleifera seeds enriched in the WSMoL lectin, known to show larvicidal and ovicidal activities against A. aegypti, were developed. The compatibility between the fraction and the excipients used in obtaining the tablets was evaluated by thermogravimetry (TG), differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR) absorption spectroscopy. The larvicidal and ovicidal activities of the resulting tablets [5%, 10%, and 15% (w/w) of the fraction] were evaluated, as well as their effect on mosquito oviposition. Assays were also performed using a placebo tablet. According to the TG, DSC, and FTIR results, the protein composition of the fraction did not change when mixed with the components of the formulation. Tablets containing 10% and 15% WSMoL-rich fraction caused mortality of 42.5% and 95% of the larvae after 48 h, respectively, with larvae incubated with these tablets showing reduced acetylcholinesterase activity. All tablets inhibited egg hatching after 72 h (36-74%), and tablets containing 15% fraction were found to exert a repellent effect on oviposition. Our results show that the formulation developed in this study interfered with the life cycle of A. aegypti, and thus show potential for use in the control of this mosquito.
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Aedes/efectos de los fármacos , Insecticidas/farmacología , Lectinas/farmacología , Moringa oleifera/química , Extractos Vegetales/farmacología , Semillas/química , Animales , Femenino , Insecticidas/química , Larva/efectos de los fármacos , Lectinas/química , Oviposición/efectos de los fármacos , Extractos Vegetales/químicaRESUMEN
This work proposes the development and characterization of solid lipid nanoparticles (SLNs) loaded with rifampicin (RIF) aiming to enhance mucoadhesion of the SLNs and consequently internalization by the alveolar macrophages (AMs). The lipid nanoparticles (NPs) were characterized and the results showed that the NPs obtained present a spherical or a starry shape with diameter around 250-500 nm, a monodisperse population, with zeta potential between -31 mV for uncoated SLNs and +33 mV for coated SLNs. The drug EE was approximately 90 % and the loading capacity (LC) 4.5 %. The SLNs coated with chitosan by the association method (aC-SLNs) show an effective mucoadhesive profile, verified by the turdimetry and surface loading method, corroborated with the cellular assays. The presence of chitosan in the aC-SLNs promotes higher mucoadhesive properties to the NPs and permeability in A549, suggesting that the safe aC-SLNs-RIF can be used as a promising drug delivery system for improving tuberculosis treatment.
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Antibióticos Antituberculosos/administración & dosificación , Quitosano/química , Portadores de Fármacos/química , Lípidos/química , Macrófagos Alveolares/efectos de los fármacos , Nanopartículas/química , Rifampin/administración & dosificación , Células A549 , Liberación de Fármacos , Humanos , Tamaño de la Partícula , Tuberculosis/tratamiento farmacológicoRESUMEN
BACKGROUND: Efavirenz is the most used medication in the treatment of Acquired Immunodeficiency Syndrome (AIDS). The limited number of pediatric antiretroviral formulations approved by regulatory agencies is the most significant obstacle to adequate and efficient pharmacotherapy for this group of patients. The efavirenz has excellent therapeutic potential, but has low aqueous solubility/bioavailability. METHODS: To minimize these limitations, multicomponent systems with ß-cyclodextrin and polyvinylpyrrolidone K-30 were obtained. Due to the limited number of pediatric antiretroviral formulations, the development of a pediatric orodispersible tablet is an alternative that is thought easy to administer, since it disintegrates rapidly in the oral cavity. The multicomponent systems were obtained by the method of kneading and characterized by solubility test, X-ray diffraction, differential scanning calorimetry and infrared absorption spectroscopy by Fourier transform. The orodispersible tablets were prepared by direct compression. The quality control of hardness, friability, disintegration, and dissolution was performed. The influence of the components of the formulation on the characteristics of the tablets was evaluated through a 22 factorial design added with three central points, to compare the effect of the dependent variables on the responses. RESULTS: An increase in drug solubility was observed, with a decrease in crystallinity. Besides that, an excellent dissolution profile presented with more than 83% of the drug's content dissolved in less than 15 minutes. Satisfactory disintegration time and friability were observed. CONCLUSION: It was observed that reduced concentrations of mannitol decreased the hardness and disintegration time of the formulations. The orodispersible tablet composed of efavirenz: ß- cyclodextrin: polyvinylpyrrolidone, favors greater absorption and bioavailability. It has several advantages for pediatric patients, as the dosage form disintegrates quickly in the mouth and does not require water for administration, thereby improving patient compliance with the treatment.
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Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Alquinos/uso terapéutico , Benzoxazinas/uso terapéutico , Ciclopropanos/uso terapéutico , Inhibidores de la Transcriptasa Inversa/uso terapéutico , beta-Ciclodextrinas/uso terapéutico , Administración Oral , Rastreo Diferencial de Calorimetría , Composición de Medicamentos , Dureza , Humanos , Pediatría , Solubilidad , Comprimidos/químicaRESUMEN
BACKGROUND: The development of antiretroviral associations in a single dosage form aims to ensure improved efficacy, low costs and better adherence to treatment. OBJECTIVE: This work performed the pharmacotechnical development, coating, and stability studies of fixed-dose combination tablets of zidovudine, lamivudine and nevirapine (300 + 200 + 150 mg, respectively). METHODS: Qualitative and quantitative planning of diluents (101 and 250 microcrystalline cellulose, spray-dried monohydrate lactose and corn starch) and coating polymers (Opadry white II HP® and Instacoat Aqua Moistshield II®) were analyzed, and direct compression (DC) and wet granulation (WG) methods were tested aiming the development of the pharmaceutical form. Quality control was carried out according to the specifications set by official compendia. The chosen formulation was scaled-up and the industrial batches were submitted to accelerated and long-term stability studies. RESULTS: The batches obtained by WG met the requirements, using 101 microcrystalline cellulose, corn starch and Opadry white II HP® as excipients. The DC trial was not possible due to the need of a greater ratio of excipients to improve formulation properties. CONCLUSION: Thus, this study brings a new therapeutic alternative for HIV treatment, contributing to the development of another possibility to simplify drug administration.
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Fármacos Anti-VIH/farmacología , Combinación de Medicamentos , Lamivudine/farmacología , Nevirapina/farmacología , Comprimidos , Zidovudina/farmacología , Composición de Medicamentos , Desarrollo de Medicamentos , Estabilidad de Medicamentos , Tecnología Farmacéutica/métodosRESUMEN
Ximenia americana L. (Olacaceae) is used in ethnomedicine as cicatrizant and for the treatment of gastric disorders. This study identified the chemical constituents of the aqueous extract of X. americana (XaAE) and evaluated its antiulcerogenic activity. After lyophilization, XaAE was analyzed by liquid chromatography-mass spectrometry (LC-MS) and its antiulcerogenic effect was evaluated in acute gastric lesions induced by ethanol, acidified ethanol, and indomethacin. Antisecretory action, mucus production and the participation of sulfhydryl groups (-SH) and nitric oxide (NO) were also investigated. The chromatographic analysis identified procyanidins B and C and catechin/epicatechin as major compounds. Oral administration of XaAE (100, 200 and 400 mg/kg) inhibited the gastric lesions induced by ethanol (76.1%, 77.5% and 100%, respectively), acidified ethanol (44.9%, 80.6% and 94.9%, respectively) and indomethacin (56.4%, 52.7% and 64.9%, respectively). XaAE reduced gastric contents and acidity (51.4% and 67.7%, respectively) but did not alter the production of gastric mucus. The reduction of the -SH and NO groups promoted by N-ethylmaleimide (NEM) and Nω-nitro-l-arginine-methyl-ester (L-NAME) respectively, reduced the gastroprotective effect of XaAE. In conclusion, XaAE has gastroprotective activity mediated in part by -SH, NO and antisecretory activity. This antiulcer action was initially correlated to its major constituents, procyanidins B and C and catechin/epicatechin.
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Enfermedades Gastrointestinales/prevención & control , Olacaceae/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Metabolismo Secundario , Animales , Arginina/análogos & derivados , Arginina/química , Catequina/química , Catequina/farmacología , Cromatografía Líquida de Alta Presión/métodos , Etanol/química , Enfermedades Gastrointestinales/inducido químicamente , Indometacina/química , Espectrometría de Masas/métodos , Ratones , Fitoterapia/métodos , Extractos Vegetales/aislamiento & purificación , Proantocianidinas/química , Proantocianidinas/farmacología , Sustancias Protectoras/química , Sustancias Protectoras/aislamiento & purificación , Sustancias Protectoras/farmacología , Ratas , Ratas Wistar , Estómago/efectos de los fármacos , AguaRESUMEN
Neglected tropical diseases (NTDs) affect millions of people in different geographic regions, especially the poorest and most vulnerable. Currently NTDs are prevalent in 149 countries, seventeen of these neglected tropical parasitic diseases are classified as endemic. One of the most important of these diseases is schistosomiasis, also known as bilharzia, a disease caused by the genus Schistosoma. It presents several species, such as Schistosoma haematobium, Schistosoma japonicum and Schistosoma mansoni, the latter being responsible for parasitosis in Brazil. Contamination occurs through exposure to contaminated water in the endemic region. This parasitosis is characterized by being initially asymptomatic, but it is able to evolve into more severe clinical forms, potentially causing death. Globally, more than 200 million people are infected with one of three Schistosome species, including an estimated 40 million women of reproductive age. In Brazil, about 12 million children require preventive chemotherapy with anthelmintic. However, according to the World Health Organization (WHO), only about 15% of the at-risk children receive regular treatment. The lack of investment by the pharmaceutical industry for the development and/or improvement of new pharmaceutical forms, mainly aimed at the pediatric public, is a great challenge. Currently, the main forms of treatment used for schistosomiasis are praziquantel (PZQ) and oxaminiquine (OXA). PZQ is the drug of choice because it presents as a high-spectrum anthelmintic, used in the treatment of all known species of schistosomiasis and some species of cestodes and trematodes. OXA, however, is not active against the three Schistosome species. This work presents a literature review regarding schistosomiasis. It addresses points such as available treatments, the role of the pharmaceutical industry against neglected diseases, and perspectives for treatment.
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Antihelmínticos/uso terapéutico , Enfermedades Desatendidas/tratamiento farmacológico , Oxamniquina/uso terapéutico , Praziquantel/uso terapéutico , Esquistosomiasis/tratamiento farmacológico , Animales , Investigación Biomédica , Brasil , Niño , Femenino , Humanos , Schistosoma haematobium , Schistosoma japonicum , Schistosoma mansoni , Esquistosomiasis/epidemiología , Microbiología del AguaRESUMEN
Solid dispersions have been used as a strategy to improve the solubility, dissolution rate, and bioavailability of poor water-soluble drugs. The increase of the dissolution rate presented by (5Z)-3-(4-chloro-benzyl)-5-(4-nitro-benzylidene)-imidazolidine-2,4-dione (LPSF/FZ4) from the solid dispersions is related to the existence of intermolecular interactions of hydrogen bond type (>N-H···O<) between the amide group (>N-H) of the LPSF/FZ4 and the ether group (-O-) of the polyethyleneglycol polymer, or the carbonyl (C=O) of the polyvinylpyrrolidone polymer (PVP). The intensity of these interactions is directly reflected in the morphology acquired by LPSF/FZ4 in these systems, where a new solid phase, in the form of amorphous aggregates of irregular size, was identified through scanning electron microscopy and confirmed in the characterizations achieved using X-ray diffraction and thermal analysis of DSC. The solid dispersions with the polymer PVP, in higher concentrations, were revealed to be the best option to be used in the formulations of LPSF/FZ4 in both theoretical and experimental studies.