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1.
Data Brief ; 33: 106445, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33110933

RESUMO

The COVID-19 outbreak is now one of the most critical crises to manage for most of national healthcare systems in the world. The situation is complicated by the absence of vaccines and authorized pharmacological treatments, except for remdesivir. In this context, many medicaments, including different Ebola and HIV antivirals, are used off-label in the hospital wards as life-treating medicines for COVID-19 patients. Authorized medicaments manipulation is sometimes necessary because they are not always formulated to be administered to non-cooperative patients or they are in shortage. It is this the case of the fixed combination of lopinavir/ritonavir, which was extensively used in the first phase of the outbreak inducing a shortage of the oral solution available in the EU market. This work provides data on size distribution, osmolarity other than drug chemical stability of a lopinavir/ritonavir extemporaneous preparation made by using the solid dosage form (i.e., tablet) available on the market as drug source. The reported data indicate that such preparation is suitable to be delivered through a nasogastric tube, and enough stable for two weeks from the preparation at room temperature.

2.
Data Brief ; 32: 106116, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32802924

RESUMO

The COVID-19 outbreak is spreading worldwide pushing the national healthcare systems to find effective protocols to prevent contagion and to reduce the patients' mortality and the severity of long-term effects. In the absence of authorised pharmacological treatments, chloroquine, and hydroxychloroquine, which are known as anti-malaria drugs, had been widely used off-label until concerns about their efficacy/safety limited their use to hospitalized patients affected by severe COVID-19. Regardless of their clinical use, their manipulation is necessary since the pure drug substance is not always promptly available and most of the drug products available on the market are tablets designed to be ingested; no liquid dosage forms are available. These are needed for children and the enteral nutrition of inpatients of intensive care units. Considering that both chloroquine and hydroxychloroquine are BCS class I, proper procedures for purifying the preparation from the insoluble excipients may be adopted to avoid clogging of a nasogastric tube and to reduce the drug content variability in the administered doses. The data in this article indicate that compounded oral suspensions containing chloroquine and hydroxychloroquine can be filtered and/or centrifuged without altering the drug assay of the preparation.

3.
Data Brief ; 30: 105552, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32292805

RESUMO

The COVID-19 outbreak is now one of the most critical crises to manage for most of the national healthcare systems in the world. In the absence of authorised pharmacological treatments, many antiretrovirals, including darunavir/cobicistat fixed combination, are used off-label in the hospital wards as life-treating medicines for COVID-19 patients. Unfortunately, for most of them, the drug products available on the market are not designed to be administered by a nasogastric tube to inpatients of intensive care units. Therefore, their manipulation, even if it can strongly affect the product quality, is necessary for the preparation of suspension to meet patients' need. In this situation, it is urgent to provide data and guidance to support hospital pharmacists and clinicians in their activity. The data in this article indicate that darunavir/cobicistat suspensions compounded by pharmacists using as active ingredient a commercially available tablet can be stable at least for one week.

4.
J Pharm Biomed Anal ; 159: 192-199, 2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-29990886

RESUMO

In this manuscript we aimed at the simultaneous separation and quantification of Gemcitabine and Irinotecan hydrochloride (injected both as single components and in combination) from Sprague Dawley rat plasma by using a validated method obtained through the use of a High Performance Liquid Chromatography (HPLC)-diode array detector (DAD). Gemcitabine and Irinotecan hydrochloride were detected and quantified using a Zorbax Extend C-18 column (250 mm × 4.6 mm; 5 µm particle size) in gradient elution mode. The chromatographic analyses were carried out in 15 min. The analytical mode was calibrated and validated in the concentration range from 0.1 to 18 µg/mL both for Gemcitabine and Irinotecan hydrochloride. Sprague Dawley rat plasma was used to perform the analysis. 3-methylxanthine was the internal standard. The weighted-matrix matched standard curves of Gemcitabine and Irinotecan hydrochloride showed a good linearity up to 18 µg/mL. Parallelism tests were also performed to evaluate whether the over-range samples could be analyzed after dilution without affecting the analytical performance. The intra- and inter-day precision (RSD%) values of Gemcitabine and Irinotecan hydrochloride were ≤7.14% and ≤11.5%, respectively. The intra- and inter-day trueness (Bias%) values were in the range from -11.5% to 1.70% for both drugs. The analytical mode performance was further tested after collecting Sprague Dawley rat plasma following a single-dose administration of chemotherapeutics or their association. The validated HPLC-DAD method allowed the simultaneous quantification of Gemcitabine and Irinotecan hydrochloride in the rat plasma, besides the evaluation of the pharmacokinetic parameters and drug delivery.


Assuntos
Antimetabólitos Antineoplásicos/sangue , Antineoplásicos Fitogênicos/sangue , Camptotecina/análogos & derivados , Técnicas de Química Analítica/métodos , Desoxicitidina/análogos & derivados , Animais , Antimetabólitos Antineoplásicos/administração & dosagem , Antineoplásicos Fitogênicos/administração & dosagem , Camptotecina/administração & dosagem , Camptotecina/sangue , Cromatografia Líquida de Alta Pressão/métodos , Desoxicitidina/administração & dosagem , Desoxicitidina/sangue , Injeções Intravenosas , Irinotecano , Ratos , Ratos Sprague-Dawley , Gencitabina
5.
BioDrugs ; 29(2): 113-21, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25773234

RESUMO

The impending expiration of patent protection for recombinant insulins provides the opportunity to introduce cost-saving copies, named biosimilars, onto the market. Although there is broad experience in the production and characterisation of insulins, the development of copies is still a challenge. In this paper, the main features of insulins and the EU regulatory framework for their biosimilar products are reviewed. The main focus is on rapid-acting insulin analogues (Humalog(®); Novolog(®)/NovoRapid(®); Apidra(®)). Since they differ by one or two amino acids in chain B, production of one biosimilar for all three drug products is not feasible. However, from post-marketing-collected clinical data, rapid-acting insulin analogues seem to have similar therapeutic efficacy. It is reasonable to suppose that, for prescription to treatment-naïve patients, the cheaper biosimilar would be the preferred choice of physicians, either spontaneously or induced by health insurance. Therefore, its introduction will affect the market share of all the other rapid-acting insulin analogues.


Assuntos
Medicamentos Biossimilares/uso terapêutico , Insulina de Ação Curta/uso terapêutico , Aprovação de Drogas , União Europeia , Humanos , Insulina/análogos & derivados , Insulina/uso terapêutico , Insulina Aspart/uso terapêutico , Insulina Lispro/uso terapêutico
6.
Int J Pharm ; 481(1-2): 79-83, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25655714

RESUMO

Low molecular weight heparins (LMWHs) are obtained from unfractionated heparin (UFH) through different depolymerization methods (DM), which produce compounds having specific chemical features and biological activity. It is then supposed that LMWHs also exhibit different skin permeability properties. The current work aimed to get an insight on the in vitro passive diffusion through human epidermis of six commercially available LMWHs in comparison with UFH. The in vitro studies were performed using Franz diffusion cells. Heparins samples were assayed measuring the anti-factor Xa activity. Circular dichroism was used to evaluate the effect of the counter-ion (sodium or calcium) on the chain flexibility. The penetrated amounts after 24h (Q24) of sodium LMWHs were related to Mw by an exponential relationship (R=-0.758). The flux resulted dependent by DM following the rank order: ß-elimination (8-11 mIU/cm(2)h range)>deaminative cleavage (5-7 mIU/cm(2)h range)>radical depolymerization (0.1mIU/cm(2)h). Finally, the calcium ion, reducing the chain flexibility, significantly affected the Q24 (0.001 ± 0.000 and 0.157 ± 0.049 IU/cm(2) for calcium and sodium nadroparin, respectively). Both the lower Mw and the introduction of new residues at the chain ends improved the skin penetration of LMWHs with respect to UFH (Q24=0.001 ± 0.001 IU/cm(2)), with bemiparin and enoxaparin being the most interesting compounds.


Assuntos
Heparina de Baixo Peso Molecular/metabolismo , Pele/metabolismo , Dicroísmo Circular , Heparina de Baixo Peso Molecular/química , Humanos , Técnicas In Vitro , Permeabilidade , Absorção Cutânea
7.
Int J Pharm ; 422(1-2): 229-37, 2012 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-22093954

RESUMO

The effects of a lipid composition on the physico-chemical and technological properties of a multidrug carrier (MDC) containing both gemcitabine (GEM) and tamoxifen (TMX), as well as its in vitro antitumoral activity on different breast cancer cell lines, were investigated. In particular, the following three different liposomal formulations were prepared: DPPC/Chol/DSPE-mPEG2000 (6:3:1 molar ratio, formulation A), DPPC/Chol/DOTAP (6:3:1 molar ratio, formulation B) and DPPC/Chol/DPPG (6:3:1 molar ratio, formulation C). The colloidal systems were obtained by the TLE technique and the extrusion process allowed us to obtain vesicles having mean sizes of 150-200 nm, while the surface charges varied between 50 mV and -30 mV. Formulation A showed the best encapsulation efficiency between the two compounds and the presence of TMX influenced the release profile of GEM (hydrophilic compound) as a consequence of its effect on the fluidity of the bilayer. An MDC of formulation A was used to effectuate the in vitro cytotoxicity experiments (MTT-test) on MCF-7 and T47D cells. The liposomal MDC provided the best results with respect to the single drug tested in the free form or entrapped in the same liposomal formulation. The CLSM experiments showed a great degree of cell interaction of liposomal MDC after just 6h.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/patologia , Lipídeos/química , 1,2-Dipalmitoilfosfatidilcolina/química , Antimetabólitos Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Colesterol/química , Coloides , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Relação Dose-Resposta a Droga , Composição de Medicamentos , Ácidos Graxos Monoinsaturados/química , Feminino , Humanos , Cinética , Lipossomos , Tamanho da Partícula , Fosfatidiletanolaminas/química , Fosfatidilgliceróis/química , Polietilenoglicóis/química , Compostos de Amônio Quaternário/química , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Solubilidade , Tamoxifeno/farmacologia , Tecnologia Farmacêutica/métodos , Gencitabina
8.
Int J Pharm ; 386(1-2): 71-6, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19900522

RESUMO

The in vitro passive diffusion of S-ibuprofen (S-IB) and RS-ibuprofen (RS-IB) through human epidermis was determined to study the effects of drug chirality. S-IB has a lower melting point (T(m)=54 degrees C) than RS-IB (T(m)=77 degrees C) and, therefore, a greater solubility (S-IB: 127+/-1 microg/mL; RS-IB: 81+/-1 microg/mL). Supersaturated plasters were prepared by using a poly(dimethylsiloxane) adhesive and Eugragit RL and propylene glycol as antinucleant agents. The in vitro skin permeation profiles were determined by Franz cells and human epidermis obtained from three different donors. The permeation profiles of S-IB from saturated solutions resulted statistically higher than those of RS-IB (p<0.002). When plasters were used, no differences were noticeable between the enantiomer and racemate (p>0.17). The latter unexpected results could be explained considering that the RS-IB or S-IB in vitro release rate constants, determined using 3% w/w or 6% w/w loaded plasters, were not statistically different, suggesting that the drug diffusivity within the adhesive matrix represented the rate limiting step to the skin absorption.


Assuntos
Anti-Inflamatórios não Esteroides/metabolismo , Epiderme/metabolismo , Ibuprofeno/metabolismo , Absorção Cutânea , Administração Cutânea , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Química Farmacêutica , Difusão , Dimetilpolisiloxanos/química , Formas de Dosagem , Composição de Medicamentos , Excipientes/química , Humanos , Ibuprofeno/administração & dosagem , Ibuprofeno/química , Cinética , Modelos Biológicos , Polímeros/química , Propilenoglicol/química , Solubilidade , Estereoisomerismo , Tecnologia Farmacêutica/métodos , Adesivos Teciduais/química , Temperatura de Transição
9.
Expert Opin Drug Deliv ; 5(7): 737-55, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18590459

RESUMO

BACKGROUND: The skin is the largest organ of our body and acts as a protective barrier with sensory and immunological functions. Its peculiar structure influences the passage of bioactives and only its modulation can facilitate the drug dermal/transdermal diffusion. In the past few years research in this field has assured better use of this application area. METHODS: One of the most promising approaches is the use of drug delivery devices; this review explains the state of the art of drug transport through the skin by means of vesicular (classic liposomes, Transfersomes, niosomes and ethosomes) and particulate systems. RESULTS/CONCLUSION: Colloidal drug delivery systems are important in the field of drug delivery systems as their different characteristics make them suitable for various purposes.


Assuntos
Administração Tópica , Coloides/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Absorção Cutânea/fisiologia , Animais , Humanos , Lipossomos , Nanopartículas , Pele/química
10.
Pharmazie ; 60(1): 36-8, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15700776

RESUMO

Recently, a supercritical carbon dioxide dried extract of Amica flower, with a very high sesquiterpene content was developed. In view of using this extract in formulations for cutaneous application, the ability of sesquiterpenes to permeate the skin was evaluated by HPLC/DAD/MS using the following permeation enhancers: oleic acid (OA), dimethylsulfoxide (DMSO), lauroglycol, isopropyl myristate and Tween 80. A skin permeation study was performed using a modified Franz diffusion cell and the human stratum corneum and epidermis as membrane. Solutions of the enhancers were directly analysed after dilution with methanol or DMSO. A simple RP-HPLC-DAD-MS method for the quantification of the sesquiterpenes was developed and the method showed no interference with the other substances extracted from the skin and the permeation enhancers. The study evidenced that among the selected skin permeation enhancers, DMSO and OA canbe considered as good candidates to be used in preparations for cutaneous application.


Assuntos
Arnica/química , Sesquiterpenos/farmacocinética , Absorção Cutânea , Dióxido de Carbono/química , Cromatografia Líquida de Alta Pressão , Cromatografia com Fluido Supercrítico , Cultura em Câmaras de Difusão , Humanos , Técnicas In Vitro , Extratos Vegetais/farmacocinética , Padrões de Referência
11.
J Control Release ; 90(3): 281-90, 2003 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-12880695

RESUMO

The beta- and gamma-irradiation effects on stability of microspheres made of poly(lactide-co-glycolide) 50:50 copolymer (PLGA) containing bupivacaine (BU) were studied. Microspheres containing 10, 25, and 40% w/w, respectively, of BU were prepared by spray drying and irradiated in air with beta- and gamma-irradiation at a dose of 25 kGy. Morphology (atomic force microscopy, particle-size analysis), physico-chemical characteristics (DSC and FT-IR spectroscopy), drug content and in vitro dissolution profile of microspheres were all determined; the stability of irradiated microspheres was evaluated over a 9-month period. The decrease of BU content in gamma-irradiated microspheres was almost always constant independent of the amount of BU per sample, therefore it was in inverse proportion to drug loading (range between 5 and 15%). BU release rate increased immediately after irradiation and increased slightly until 90 days of storage. As far as beta-irradiated microspheres are concerned, BU content decreased in a significant way (approximately 3%) only in microspheres containing 10% w/w of BU. Immediately after irradiation, drug release rate in beta-irradiated microspheres increased less than in the corresponding gamma-irradiated microspheres, and it did not change further over the following storage period. BU-loaded microspheres have been shown to be more stable against beta- than gamma-irradiation. AFM revealed that the surface roughness of the irradiated microspheres increases depending on irradiation. As such, if a parameter is quantifiable, it is proposed as a marker of degradation due to ionizing radiation.


Assuntos
Anestésicos Locais/química , Partículas beta , Bupivacaína/química , Raios gama , Glicolatos/efeitos da radiação , Varredura Diferencial de Calorimetria , Portadores de Fármacos , Estabilidade de Medicamentos , Glicolatos/química , Ácido Láctico , Microesferas , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Espectroscopia de Infravermelho com Transformada de Fourier , Esterilização/métodos , Temperatura , Fatores de Tempo
12.
Artigo em Inglês | MEDLINE | ID: mdl-12637784

RESUMO

A new nitro-oxybutylester of flurbiprofen (NO-FP) is a promising anti-inflammatory drug in the treatment of dermatological disorders, and the feasibility of its cutaneous administration was evaluated. Four different semi-solid formulations were evaluated in order to assess the influence of the composition on the drug amount retained in the stratum corneum and epidermis (SCE). The lipophilic ointment induced the highest NO-FP amount retained in the SCE and, therefore, skin permeation enhancers (Transcutol), Lauroglycol), oleic acid and isopropyl myristate) were added to this formulation. The in vitro NO-FP amounts retained in the SCE were correlated with the solubility parameters, and a good linear correlation was found (r(2) = 0.925). The formulation of the lipophilic ointment was optimized, and the activity of this preparation was verified in methyl-nicotinate-induced contact urticaria and UV-induced erythema obtaining good results in terms of efficacy and safety.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Flurbiprofeno/farmacologia , Administração Cutânea , Adulto , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Química Farmacêutica , Dermatite/tratamento farmacológico , Dermatite/etiologia , Feminino , Flurbiprofeno/análogos & derivados , Humanos , Masculino , Ácidos Nicotínicos , Pomadas , Psoríase/tratamento farmacológico , Pele/efeitos dos fármacos , Solubilidade , Fatores de Tempo , Raios Ultravioleta , Urticária/induzido quimicamente , Urticária/tratamento farmacológico
13.
J Control Release ; 88(1): 43-53, 2003 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-12586502

RESUMO

The sodium and potassium salts of the methacrylic copolymers Eudragit L100 and Eudragit S100 were prepared with the aim to develop new low-swellable mucoadhesive materials intended for the preparation of buccal dosage forms. The physico-chemical characterization of the copolymers and the corresponding sodium and potassium salts was performed by using Fourier-transform infrared (FT-IR) spectroscopy and thermal analysis. When ionization occurred, the carboxylic acid group absorption band (1730 cm(-1)) was replaced by another characteristic band at 1560 cm(-1). After salification the T(g) of the two polymers shifted towards higher values and it was not significantly influenced by the contraion nature. The intrinsic dissolution rate at infinite rotation speed (7.354

Assuntos
Lactose/análogos & derivados , Metilcelulose/análogos & derivados , Ácidos Polimetacrílicos/química , Adesivos Teciduais/química , Algoritmos , Varredura Diferencial de Calorimetria , Formas de Dosagem , Mucosa , Oxazinas , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Comprimidos , Termogravimetria
14.
Int J Pharm ; 242(1-2): 313-7, 2002 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-12176270

RESUMO

The sublingual administration of nifedipine (NIF) is currently used in clinical practice. The sublingual administration of NIF solid dispersions (SD), by using a suitable dispenser, appears an interesting approach in the treatment of moderate and severe hypertensive emergencies. With this aim nine SD made of NIF and a low viscosity hydroxypropylmethylcellulose (HPMC) in different ratio were prepared by means of spray-drying technique and their structure was studied. Moreover, the drug dissolution properties from SD were verified. The characteristic peaks of crystalline NIF were not detectable by using the X-ray analysis when the NIF/HPMC ratios were lower than 50/50 w/w. In thermograms obtained from SD, the NIF melting endothermic peak disappeared when NIF/HPMC ratios were lower than 30/70 w/w; the experimental Tg values of SD were lower than the Tg values predicted by Gordon Taylor equation suggesting some type of non-ideality of mixing. In the SD FTIR spectra the NH stretching vibrations and the C=O stretch in esteric groups of NIF shift to free NH and C=O regions indicating the rupture of intermolecular hydrogen bond in the crystalline structure of NIF. The prepared SD improved the NIF dissolution rate in comparison with that of commercial NIF or NIF/HPMC physical mixtures. Moreover, the concentration of NIF in the dissolution medium increased decreasing the NIF content.


Assuntos
Bloqueadores dos Canais de Cálcio/química , Lactose/análogos & derivados , Metilcelulose/análogos & derivados , Nifedipino/química , Administração Sublingual , Cristalografia por Raios X , Análise Diferencial Térmica , Excipientes , Oxazinas , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Farmaco ; 57(6): 427-33, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12088056

RESUMO

The effects of gamma radiation on the stability of microspheres made of a polylactide-co-glycolide 50:50 copolymer (PLGA) and loaded with 40% bupivacaine (BU) were studied. The radiolysis mechanisms of BU and BU-loaded microspheres were investigated by using electronic paramagnetic resonance (EPR) analysis. Microspheres were prepared by means of a spray drying method. Gamma Irradiation was carried out in the open, at the dose of 25 kGy, by using a 60Co source. The stability of BU-loaded microspheres was evaluated over a 1-year period on the basis of drug content and dissolution profile. Non-irradiated microspheres were stable over the whole period under consideration. Immediately after irradiation the amount of BU released after 24 h from irradiated microspheres increased from 17 to 25%; in the following 3 months of storage it increased to about 35%, and then it kept constant for 1 year. Radicals generated by BU irradiation were identified by EPR analysis; the sensitivity to gamma radiation of BU was about four times lower than that of PLGA. Furthermore, the EPR spectra of loaded microspheres showed that the relative abundance of BU radicals plus PLGA radicals was proportionate to the electronic fractions of the components; this implies that no spin transfer BU/PLGA had occurred during gamma irradiation.


Assuntos
Bupivacaína/química , Bupivacaína/efeitos da radiação , Ácido Láctico/química , Ácido Láctico/efeitos da radiação , Ácido Poliglicólico/química , Ácido Poliglicólico/efeitos da radiação , Polímeros/química , Polímeros/efeitos da radiação , Alanina/química , Compostos de Bifenilo , Radioisótopos de Cobalto/efeitos da radiação , Estabilidade de Medicamentos , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres/química , Radicais Livres/isolamento & purificação , Raios gama , Cinética , Microesferas , Oxigênio , Tamanho da Partícula , Picratos/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Padrões de Referência , Sensibilidade e Especificidade , Temperatura , Fatores de Tempo , Vácuo
16.
Drug Dev Ind Pharm ; 27(7): 711-7, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11694019

RESUMO

Dehydroepiandrosterone (DHEA) and its sulfate conjugate (DHEAS) are the major secretory steroidal products of the adrenal gland. Some epidemiologic studies have found an association between low DHEA serum levels in patients and many important diseases. To prevent all such pathological conditions and, in any case, in aging, a DHEA supplementation has been proposed. DHEA shows a low oral bioavailability; taking the bioavailability obtained by the subcutaneous route as 100%, it was estimated that the potencies of DHEA by the percutaneous and oral routes were approximately 33% and 3%, respectively. Thus, transdermal patches could be considered a promising formulation as a continuous and controlled delivery of DHEA in replacement therapy is desired. With the aim of evaluating the effect of the matrix composition in terms of polymers and enhancers on the DHEA skin permeation flux, 10 types of monolayer self-adhesive patches containing 0.25mg/cm2 of active ingredient were designed. The matrices were based on three different acrylic copolymers: an acrylate-vinylacetate copolymer, a polyaminomethylmethacrylate (PAMA), and a polymethylmethacrylate. Transcutol (TR), mint essential oil, Lauroglycol, Brij 58, and propylene glycol (PG) were evaluated as DHEA skin permeation enhancers. All prepared patches were characterized by drug content, light microscopy, and in vitro skin permeation, performed using a modified Franz-type diffusion cell and human stratum corneum and epidermis as a membrane. The in vitro skin permeation studies are particularly significant in the development studies of DHEA patches as the in vivo determination of DHEA is affected b the fact that the endogen substance in the plasma is not constant over time. Among the testedpatches, highest DHEA fluxes were obtained using the formulation based on PAMA. Moreover, the introduction in the matrix of binary mixtures of TR and PG, used also for their plasticizer properties, permitted enhancing DHEA skin permeation. On the basis of these studies, the transdermal administration of DHEA using patches seems feasible.


Assuntos
Desidroepiandrosterona/administração & dosagem , Administração Cutânea , Cromatografia Líquida de Alta Pressão , Difusão , Epiderme/metabolismo , Excipientes , Humanos , Técnicas In Vitro , Permeabilidade , Absorção Cutânea , Espectrofotometria Ultravioleta , Ultrassom
17.
J Control Release ; 75(3): 317-30, 2001 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-11489319

RESUMO

This work was aimed at evaluating the effects of gamma irradiation on the stability of microspheres made of a poly(lactide-co-glycolide) copolymer (PLGA) and loaded with 15% w/w of clonazepam (CLO). The influence of CLO on PLGA radiolysis mechanisms and the identification of possible irradiation markers were also investigated. Microspheres were prepared by means of a spray-drying method. gamma Irradiation was carried out either under vacuum or in air, at a dose of 25 kGy, by using a 60Co source. The stability of CLO loaded microspheres was evaluated over a 6-month period on the basis of drug content and dissolution profile. Radiolysis mechanisms were investigated by using electronic paramagnetic resonance (EPR) analysis. The microspheres irradiated under vacuum were stable over the considered period of time. After irradiation in air, CLO release rate increased by approximately 10%, and did not change further in the following period of storage. The EPR analysis showed some radicals arising from both the polymeric matrix and the active ingredient. Polymer/CLO spin transfer reactions suggest that CLO had a radio-stabilising effect on the polymeric matrix. In the loaded microspheres, the intensity in time of the CLO radical signal is sufficient for its possible use as irradiation marker.


Assuntos
Clonazepam/administração & dosagem , Ácido Láctico/administração & dosagem , Ácido Poliglicólico/administração & dosagem , Polímeros/administração & dosagem , Varredura Diferencial de Calorimetria , Clonazepam/química , Clonazepam/efeitos da radiação , Estabilidade de Medicamentos , Espectroscopia de Ressonância de Spin Eletrônica , Raios gama , Microesferas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Solubilidade
18.
Boll Chim Farm ; 140(2): 63-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11417388

RESUMO

The patch performances and the success of the transdermal drug delivery can be significantly affected by the quality of contact between the patch and the skin. Poor adhesion will dramatically reduce percutaneous delivery. In this study the adhesive properties (peel force and creep resistance) of three monolayer self-adhesive nitroglycerin (NTG) patches available on the market, Deponit, Minitran, and Triniplas, were compared. The patches were characterized also in terms of in vitro drug release and ex vivo skin permeation. The creep resistance values verified in the case of Deponit and Triniplas indicated a low cohesion of these matrices. The peel force values were in the accepted range, even if Triniplas and Deponit showed values double that shown by Minitran. The percentage of NTG released in vitro after two hours in all cases exceeded ninety percent. The ex vivo permeation profiles were similar, even if the three patches had different loaded amounts and surface areas. The measured permeated amount, 11 mg permeated in 24 h, was predictive of the claimed in vivo release (10 mg in 24 h).


Assuntos
Nitroglicerina/administração & dosagem , Vasodilatadores/administração & dosagem , Adesividade , Administração Cutânea , Humanos , Técnicas In Vitro , Nitroglicerina/química , Vasodilatadores/química
19.
Pharmacol Res ; 42(1): 25-31, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10860631

RESUMO

Even if a specific directive has been approved many years ago, the situation of self-medication products (OTC) in EU countries is still far from being harmonized. In Italy the market is lower than that of most other countries; in order to solve some of the major problems that led to this situation a guideline, concerning the criteria for the definition of an OTC product, and the characteristics of the label and the package leaflet, was recently published. In this document the characteristics of OTC, such as composition, indications and duration of the treatment are assessed. The European Commission has recently published a guideline on the readability of labels and package leaflets of medicinal products for human use. The two documents stated the same principles and the Italian document is in agreement with the European guidelines. In this paper the Italian situation of OTC products (definition and presentation) is presented and discussed.


Assuntos
Medicamentos sem Prescrição , Rotulagem de Medicamentos , Embalagem de Medicamentos , Humanos , Itália , Legislação de Medicamentos
20.
Eur J Pharm Sci ; 10(2): 111-7, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10727876

RESUMO

Melilot extract could be effective in treating localised varicose syndrome or capillary fragility. The monolayer patch was selected to obtain a prolonged release of coumarin contained in the phytocomplex. Two types of methacrylic patches (patch 1 based on a blend of Eudragit E100 and Eudragit NE; patch 2 based on Eudragit L100) were prepared. Both patches were equivalent in terms of coumarin release and ex vivo skin permeation profiles. The two patches differed significantly as regards respective adhesive properties. At low peel rate only patch 1 showed adhesive failure as confirmed by the in vivo performance. When comparing the behaviour of the patches containing melilot extract with analogous patches containing synthetic coumarin, no melilot phytocomplex enhancer effect was shown. The data of the ex vivo coumarin skin permeation and those obtained by the in vivo stripping technique showed a good correlation (r(2)=0.9727 for patch 1, r(2)=0.9835 for patch 2).


Assuntos
Cumarínicos/farmacologia , Extratos Vegetais/farmacologia , Resinas Vegetais/farmacologia , Rutina/farmacologia , Absorção Cutânea/efeitos dos fármacos , Adesividade , Administração Tópica , Adulto , Cromatografia Líquida de Alta Pressão , Combinação de Medicamentos , Feminino , Humanos , Técnicas In Vitro , Solubilidade , Espectrofotometria Ultravioleta
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