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1.
J Microencapsul ; 37(7): 502-516, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32842813

RESUMO

AIM: To prepare and characterise lutein-loaded polylactide-co-glycolide-polyethylene glycol-folate (PLGA-PEG-FOLATE) nanoparticles and evaluate enhanced uptake in SK-N-BE(2) cells. METHODS: Nanoparticles were prepared using O/W emulsion solvent evaporation and characterised using DLS, SEM, DSC, FTIR and in-vitro release. Lutein-uptake in SK-N-BE(2) cells was determined using flow-cytometry, confocal-microscopy and HPLC. Control was lutein PLGA nanoparticles. RESULTS: The size of lutein-loaded PLGA and PLGA-PEG-FOLATE nanoparticles were 189.6 ± 18.79 nm and 188.0 ± 4.06 nm, respectively. Lutein entrapment was ∼61%(w/w) and ∼73%(w/w) for PLGA and PLGA-PEG-FOLATE nanoparticles, respectively. DSC and FTIR confirmed encapsulation of lutein into nanoparticles. Cellular uptake studies showed ∼1.6 and ∼2-fold enhanced uptake of lutein from PLGA-PEG-FOLATE nanoparticles compared to PLGA nanoparticles and lutein, respectively. Cumulative release of lutein was higher in PLGA nanoparticles (100% (w/w) within 24 h) compared to PLGA-PEG-FOLATE nanoparticles (∼80% (w/w) in 48 h). CONCLUSION: Lutein-loaded PLGA-PEG-FOLATE nanoparticles could be a potential treatment for hypoxic ischaemic encephalopathy.


Assuntos
Portadores de Fármacos/química , Ácido Fólico/análogos & derivados , Luteína/administração & dosagem , Poliésteres/química , Polietilenoglicóis/química , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Ácido Fólico/química , Humanos , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Luteína/farmacocinética
2.
Int J Pharm Compd ; 23(4): 340-350, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31315086

RESUMO

The objective of this study was to develop a validated stability-indicating high-performance liquid chromatographic method that quantifies progesterone in compounded glycerinated gelatin troches. The mobile phase was composed of methanol and water (75:25 v/v), while the stationary phase was a Waters Nova-Pak C18 column (3.9 mm Å~ 15 cm Å~ 4.0 µm) with the column's temperature set to 40°C. The injection volume was 20 µL, while the gradient flow rate was maintained at 0.75 mL/min for a run time of 15 minutes. The detection wavelength for progesterone was set to 245 nm. In the forced degradation study, there was significant hydrolytic, oxidative, ultraviolet, and thermal degradation but insignificant photodegradation. However, no degradants co-eluted with progesterone. All method validation parameters met the respective acceptance criteria established by the International Conference on Harmonisation guidelines. This developed and validated method is suitable for both routine potency/strength testing as well as stability testing of progesterone in compounded glycerinated gelatin troche dosage forms. The method was utilized to successfully quantify progesterone in multiple compounded preparations from two different compounding pharmacies.


Assuntos
Gelatina , Progesterona , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos
3.
Int J Pharm Compd ; 23(1): 62-64, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30668536

RESUMO

Progesterone is a naturally occurring female sex hormone, which plays an important role in the female reproductive cycle. Progesterone supplementation is used to treat a variety of conditions. When commercial dosage strengths are unavailable, rapid-dissolving tablets may be compounded. The objective of this study was to evaluate the chemical stability of progesterone when compounded in a rapid-dissolving tablet formulation and to establish an evidence-based beyond-use date. Triplicate test samples were prepared by diluting the pulverized progesterone rapid-dissolving tablets with a portion of methanol to a final concentration of 100 µg/mL. Samples were stored in a stability chamber under accelerated conditions at 60°C and 75% relative humidity and were evaluated at appropriate intervals (0, 6 months, and 12 months). Chemical stability was assessed initially and at appropriate intervals during the study periods with stability-indicating high-performance liquid chromatography analytical techniques based on the determination of drug concentrations. The results of high-performance liquid chromatography analysis indicated that the samples remained stable for 6 months at 60°C and 75% relative humidity. The remaining concentration of progesterone rapid-dissolving tablets at 6 months fell within the United States Pharmacopeia accepted limits (±10% of the initial concentration), which was consistent with the recommended beyond-use dating of 6 months for a non-aqueous formulation per United States Pharmacopeia guidelines.


Assuntos
Cromatografia Líquida de Alta Pressão/instrumentação , Progesterona , Cromatografia Líquida de Alta Pressão/métodos , Estabilidade de Medicamentos , Progesterona/metabolismo , Comprimidos
4.
Eur J Pharm Biopharm ; 104: 42-50, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27108266

RESUMO

7-Ethyl-10-hydroxycamptothecin (SN38) is a biologically active metabolite of irinotecan. Due to the variability of irinotecan metabolism rate to SN38, and poor solubility of this compound in pharmaceutically acceptable solvents, SN38 has not been successfully used in the clinic. In the present study, we prepared solid lipid nanoparticle (SLN) formulations containing SN38 and evaluated the in vitro and in vivo efficacy of these nanoparticles. SLNs and PEGylated SLNs containing SN38 (SLN-SN38 and PEG-SLN-SN38) were prepared using ultrasonication technique. Nanoparticles were characterized for size, zeta potential, and drug encapsulation efficiency. In vitro cytotoxicity of these compounds was evaluated in two colorectal carcinoma cell lines, namely C-26 and HT-116. In vivo antitumor efficacy of the formulations was evaluated in C-26 xenograft tumor mice models. Mice survival was also explored through 60days post IV injection. Mean size of SLN-SN38 and PEG-SLN-SN38 was around 103 and 131nm, respectively. Polydispersity index (PDI) for all the formulations was around 0.2 and zeta potential was negative (-5 to -15mV). Nearly 90% of the drug was encapsulated in SLNs. SLN-SN38 and PEG-SLN-SN38 compared to irinotecan were significantly more toxic to C-26 and HT-116 cell lines after 48h of exposure. Calculation of IC50 suggests higher sensitivity of HT-116 cells than C-26 cells to SLN-SN38 and PEG-SLN-SN38. Tumor inhibitory efficacy presented the highest efficacy in SLN-SN38. However, both SLN-SN38 and PEG-SLN-SN38 carriers showed higher efficiency to inhibit tumors compared to irinotecan (25mg/kg).


Assuntos
Antineoplásicos Fitogênicos/química , Camptotecina/análogos & derivados , Lipídeos/química , Nanopartículas , Animais , Varredura Diferencial de Calorimetria , Camptotecina/química , Linhagem Celular Tumoral , Xenoenxertos , Humanos , Técnicas In Vitro , Irinotecano , Camundongos , Microscopia Eletrônica de Transmissão , Taxa de Sobrevida
5.
Expert Opin Drug Deliv ; 9(3): 287-301, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22339554

RESUMO

INTRODUCTION: Resistance to chemotherapy is a major obstacle in the successful amelioration of tumors in many cancer patients. Resistance is either intrinsic or acquired, involving mechanisms such as genetic aberrations, decreased influx and increased efflux of drugs. Strategies for the reversal of resistance involve the alteration of enzymes responsible for drug resistance, the modulation of proteins regulating apoptosis mechanisms and improving the uptake of drugs using nanotechnology. Novel strides in the reversal of drug resistance are emerging, involving the use of nanotechnology, targeting stem cells, etc. AREAS COVERED: This paper reviews the most recent cancer drug reversal strategies involving nanotechnology for targeting cancer cells and cancer stem cells (CSCs), for enhanced uptake of micro- and macromolecular inhibitors. EXPERT OPINION: Nanotechnology used in conjunction with existing therapies, such as gene therapy and P-glycoprotein inhibition, has been shown to improve the reversal of drug resistance; the mechanisms involved in this include specific targeting of drugs and nucleotide therapeutics, enhanced cellular uptake of drugs and improved bioavailability of drugs with poor physicochemical characteristics. Important strategies in the reversal of drug resistance include: a multifunctional nanoparticulate system housing a targeting moiety; therapeutics to kill resistant cancer cells and CSCs; cytotoxic drugs and a tumor microenvironment stimuli-responsive element, to release the encapsulated therapeutics.


Assuntos
Antineoplásicos/administração & dosagem , Portadores de Fármacos/administração & dosagem , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Terapia de Alvo Molecular/métodos , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Aptâmeros de Nucleotídeos/administração & dosagem , Resistência a Medicamentos/efeitos dos fármacos , Resistência a Múltiplos Medicamentos , Humanos , MicroRNAs/administração & dosagem , MicroRNAs/antagonistas & inibidores , Terapia de Alvo Molecular/instrumentação , Células-Tronco Neoplásicas/efeitos dos fármacos , RNA Interferente Pequeno/administração & dosagem , Microambiente Tumoral
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