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1.
Eur J Pharm Biopharm ; 200: 114307, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38685438

RESUMO

Herein, we report the properties of nanostructured lipid carriers (NLCs) prepared with a gradient concentration of Bergenin (BGN) isolated from Pentaclethra macrophylla stem bark powder. A gradient concentration of BGN (BGN 0, 50, 100, 150, and 200 mg) was prepared in a 5 % lipid matrix consisting of Transcutol HP (75 %), Phospholipon 90H (15 %), and Gelucire 43/01 (10 %) to which a surfactant aqueous phase consisting of Tween 80, sorbitol, and sorbic acid was dissolved. The NLCs were evaluated by size, polydispersity index (PDI), zeta potential, Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), encapsulation efficiency, and in vitro drug release. The result shows polydispersed nanoparticles with high drug encapsulation (94.26-99.50 %). The nanoparticles were mostly spherical, but those from the 50 mg BGN batch were more cuboidal than spherical. The drug release was highest from the latter to the tune of 40 % compared to the pure BGN solution, which released about 15 % BGN. The anti-inflammatory activity of the BGN-NLC and total plant extract was studied on lipopolysaccharide (LPS)-inflamed macrophages. The cell study showed that BGN and plant extract had low cytotoxicity on macrophages and exhibited a dose-dependent anti-inflammatory effect on the LPS-induced inflammatory process in macrophages.


Assuntos
Anti-Inflamatórios , Benzopiranos , Portadores de Fármacos , Lipídeos , Lipopolissacarídeos , Macrófagos , Nanopartículas , Lipopolissacarídeos/farmacologia , Animais , Camundongos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/química , Portadores de Fármacos/química , Benzopiranos/farmacologia , Benzopiranos/administração & dosagem , Benzopiranos/química , Nanopartículas/química , Lipídeos/química , Células RAW 264.7 , Liberação Controlada de Fármacos , Nanoestruturas/química , Saxifragaceae/química , Tamanho da Partícula , Inflamação/tratamento farmacológico , Inflamação/induzido quimicamente , Extratos Vegetais/farmacologia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química
2.
J Control Release ; 354: 465-488, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36642250

RESUMO

Diseases affecting the anterior segment of the eye are the primary causes of vision impairment and blindness globally. Drug administration through the topical ocular route is widely accepted because of its user/patient friendliness - ease of administration and convenience. However, it remains a significant challenge to efficiently deliver drugs to the eye through this route because of various structural and physiological constraints that restrict the distribution of therapeutic molecules into the ocular tissues. The bioavailability of topically applied ocular medications such as eye drops is typically less than 5%. Developing novel delivery systems to increase the retention time on the ocular surfaces and permeation through the cornea is one of the approaches adopted to boost the bioavailability of topically administered medications. Drug delivery systems based on nanotechnology such as micelles, nanosuspensions, nanoparticles, nanoemulsions, liposomes, dendrimers, niosomes, cubosomes and nanowafers have been investigated as effective alternatives to conventional ocular delivery systems in treating diseases of the anterior segment of the eye. This review discussed different nanotechnology-based delivery systems that are currently investigated for treating and managing diseases affecting the anterior ocular tissues. We also looked at the challenges in translating these systems into clinical use and the prospects of nanocarriers as a vehicle for the delivery of phytoactive compounds to the anterior segment of the eye.


Assuntos
Sistemas de Liberação de Medicamentos , Oftalmopatias , Humanos , Oftalmopatias/tratamento farmacológico , Olho , Nanotecnologia , Lipossomos/uso terapêutico , Córnea , Administração Oftálmica
3.
Methods Microbiol ; 50: 151-188, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38620863

RESUMO

The outbreak of the COVID-19 pandemic in 2019 has been one of the greatest challenges modern medicine and science has ever faced. It has affected millions of people around the world and altered human life and activities as we once knew. The high prevalence as well as an extended period of incubations which usually does not present with symptoms have played a formidable role in the transmission and infection of millions. A lot of research has been carried out on developing suitable treatment and effective preventive measures for the control of the pandemic. Preventive strategies which include social distancing, use of masks, washing of hands, and contact tracing have been effective in slowing the spread of the virus; however, the infectious nature of the SARS-COV-2 has made these strategies unable to eradicate its spread. In addition, the continuous increase in the number of cases and death, as well as the appearance of several variants of the virus, has necessitated the development of effective and safe vaccines in a bid to ensure that human activities can return to normalcy. Nanotechnology has been of great benefit in the design of vaccines as nano-sized materials have been known to aid the safe and effective delivery of antigens as well as serve as suitable adjuvants to potentiate responses to vaccines. There are only four vaccine candidates currently approved for use in humans while many other candidates are at various levels of development. This review seeks to provide updated information on the current nano-technological strategies employed in the development of COVID-19 vaccines.

4.
Ther Deliv ; 12(9): 671-683, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34374581

RESUMO

Aim: Anterior eye segment disorders are treated with eye drops and ointments, which have low ocular bioavailability necessitating the need for improved alternatives. Lipid microsuspension of gentamicin sulphate was developed for the treatment of susceptible eye diseases. Materials & methods: Lipid microsuspensions encapsulating gentamicin sulphate were produced by hot homogenization and evaluated. Ex vivo permeation and ocular irritancy tests were also conducted. Results & conclusion: Stable microsuspensions with high entrapment efficiency and satisfactory osmolarities were obtained. Release studies achieved 49-88% in vitro release at 12 h with sustained permeability of gentamicin compared with conventional gentamicin eye drop (Evril®). No irritation was observed following Draize's test. The microsuspensions have great potential as ocular delivery system of gentamicin sulphate.


Assuntos
Olho , Gentamicinas , Disponibilidade Biológica , Sistemas de Liberação de Medicamentos , Lipídeos , Soluções Oftálmicas
5.
Biomed Res Int ; 2018: 3714329, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29977910

RESUMO

The aim of this study was to investigate the potential of microparticles based on biocompatible phytolipids [Softisan® 154 (SF) (hydrogenated palm oil) and super-refined sunseed oil (SO)] and polyethylene glycol- (PEG-) 4000 to improve intravaginal delivery of miconazole nitrate (MN) for effective treatment of vulvovaginal candidiasis (VVC). Lipid matrices (LMs) consisting of rational blends of SF and SO with or without PEG-4000 were prepared by fusion and characterized and employed to formulate MN-loaded solid lipid microparticles (SLMs) by melt-homogenization. The SLMs were characterized for physicochemical properties, anticandidal activity, and stability. Spherical discrete microparticles with good physicochemical properties and mean diameters suitable for vaginal drug delivery were obtained. Formulations based on SO:SF (1:9) and containing highest concentrations of PEG-4000 (4 %w/w) and MN (3.0 %w/w) were stable and gave highest encapsulation efficiency (83.05-87.75%) and inhibition zone diameter (25.87±0.94-26.33±0.94 mm) and significantly (p<0.05) faster and more powerful fungicidal activity regarding killing rate constant values (7.10 x 10-3-1.09 x 10-2 min-1) than commercial topical solution of MN (Fungusol®) (8.00 x 10-3 min-1) and pure MN sample (5.160 x 10-3 min-1). This study has shown that MN-loaded SLMs based on molecularly PEGylated lipid matrices could provide a better option to deal with VVC.


Assuntos
Antifúngicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Miconazol/administração & dosagem , Feminino , Humanos , Tamanho da Partícula , Vagina
6.
BMC Health Serv Res ; 18(1): 92, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29422062

RESUMO

BACKGROUND: Availability and accessibility of sexual and reproductive health services for adolescents are very crucial for prevention and control of sexual and reproductive health problems. These services also play vital roles in the promotion of adolescents' sexual and reproductive health generally. The main purpose of the study was to determine the availability and accessibility (geographical and financial) of sexual and reproductive health services (SRHS) among adolescents in Enugu State, Nigeria. METHODS: A mixed methods approach was adopted for the study. 192 health facilities were reached to check availability of SRH services. Randomly sampled 1447 adolescents (12-22 years) completed the questionnaire correctly. Twenty-seven interviews and 18 group discussions were conducted. Instruments for data collection consisted of a checklist, a questionnaire, a focus group discussion guide and an in-depth interview guide. All instruments were pre-tested. Quantitative data were analyzed using descriptive statistics and Chi-square tests. NVivo 11 Pro software was used to code and thematically analyze the qualitative data. RESULTS: A total of 1447 adolescents (between 12 and 22 years) completed the questionnaire correctly. Among these adolescents, males constituted 42.9% while females were 57.1%. The majority (86.7%) of the adolescents reported availability of safe motherhood services, and 67.5% reported availability of services for prevention and management of STIs and HIV and AIDS. The majority reported that these services were geographically accessible but few were financially accessible to adolescents. However, qualitative data revealed that available services were not specifically provided for adolescents but for general use. Age (p = ≤ .05), education (p = ≤ .05) and income (p = ≤ .05) were found to be significantly associated with access to SRHS. CONCLUSION: SRHS were generally physically available but not financially accessible to adolescents. Adolescents' clinics were not available and this could affect the access of SRHS by adolescents. Education and income were significantly associated with access to SRHS.


Assuntos
Serviços de Saúde do Adolescente/provisão & distribuição , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Serviços de Saúde Reprodutiva/provisão & distribuição , Adolescente , Feminino , Grupos Focais , Humanos , Masculino , Nigéria , Saúde Reprodutiva , Infecções Sexualmente Transmissíveis/prevenção & controle , Inquéritos e Questionários , Adulto Jovem
7.
Int J Nanomedicine ; 11: 6365-6378, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27932882

RESUMO

The present study aimed to develop low-dose liquisolid tablets of two antimalarial drugs artemether-lumefantrine (AL) from a nanostructured lipid carrier (NLC) of lumefantrine (LUM) and estimate the potential of AL as an oral delivery system in malariogenic Wistar mice. LUM-NLCs were prepared by hot homogenization using Precirol® ATO 5/Transcutol® HP and tallow fat/Transcutol® HP optimized systems containing 3:1 ratios of the lipids, respectively, as the matrices. LUM-NLC characteristics, including morphology, particle size, zeta potential, encapsulation efficiency, yield, pH-dependent stability, and interaction studies, were investigated. Optimized LUM-NLCs were mixed with artemether powder and other dry ingredients and the resultant powder evaluated for micromeritics. Subsequent AL liquisolid tablets were tested for in vitro drug release and in vivo antiplasmodial activity in mice infected with Plasmodium berghei berghei (NK 65). Results showed that optimized LUM-NLC were stable, spherical, polydispersed but nanometric. Percentage yield and encapsulation efficiency were ~92% and 93% for Precirol® ATO 5/Transcutol® HP batch, then 81% and 95% for tallow fat/Transcutol® HP batch while LUM was amorphous in NLC matrix. In vitro AL release from liquisolid compacts revealed initial burst release and subsequent sustained release. Liquisolid tablet compacts formulated with Precirol® ATO 5/Transcutol® HP-AL4 achieved higher LUM release in simulated intestinal fluid (84.32%) than tallow fat/Transcutol® HP-BL3 (77.9%). Non-Fickian (anomalous) diffusion and super case II transport were the predominant mechanisms of drug release. Equal parasitemia reduction was observed for both batches of tablet compacts (~92%), superior to the reduction obtained with commercial antimalarial formulations: Coartem® tablets (86%) and chloroquine phosphate tablets (66%). No significant difference (P<0.05) in parasite reduction between double (4/24 mg/kg) and single (2/12 mg/kg) strength doses of AL compacts was observed. Our result highlights that AL could be formulated in much lower doses (4/24 mg/kg), for once-in-two days oral administration to improve patient compliance, which is currently not obtainable with conventional AL dosage forms.


Assuntos
Artemisininas/uso terapêutico , Etanolaminas/uso terapêutico , Fluorenos/uso terapêutico , Malária/tratamento farmacológico , Cooperação do Paciente , Animais , Antimaláricos/administração & dosagem , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Combinação Arteméter e Lumefantrina , Artemisininas/administração & dosagem , Artemisininas/química , Artemisininas/farmacologia , Varredura Diferencial de Calorimetria , Preparações de Ação Retardada/farmacologia , Preparações de Ação Retardada/uso terapêutico , Portadores de Fármacos/química , Combinação de Medicamentos , Liberação Controlada de Fármacos , Etanolaminas/administração & dosagem , Etanolaminas/química , Etanolaminas/farmacologia , Fluorenos/administração & dosagem , Fluorenos/química , Fluorenos/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Cinética , Lipídeos/química , Malária/parasitologia , Camundongos , Nanoestruturas/química , Tamanho da Partícula , Plasmodium berghei/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Comprimidos
8.
Chem Pharm Bull (Tokyo) ; 52(3): 303-6, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14993751

RESUMO

The thermodynamic parameters of the charge transfer complex between chloranilic acid and haloperidol were studied. Haloperidol in pure form and in dosage form was assayed in this study. The method was based on charge transfer complex formation between the drug, which acted as an n-donor, and chloranilic acid, which acted as a pi acceptor in a non aqueous solvent. The complex stoichiometry was found to be 1:2 (haloperidol: chloranilic acid) with the maximum absorption band at a wavelength of 576 nm. The complex obeyed Beer's law. The thermodynamic parameters investigated included stability constant, molar absorptivity, free energy change, enthalpy, and entropy. The method was successfully applied in the analysis of commercially available haloperidol tablets without interference from its excipients, with good precision and reproducibility, compared with the official assay method (non aqueous titration) described for haloperidol in the compendium.


Assuntos
Benzoquinonas/química , Haloperidol/química , Eletroquímica , Comprimidos , Termodinâmica
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