Eliana Martins Lima

Universidade Federal de Goiás, Goianá, Goiás, Brazil

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Publications (24)45.79 Total impact

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    ABSTRACT: Recent studies have shown that the antifungal itraconazole (ITZ), when in associations with benznidazole (BNZ), is a potential treatment for Chagas disease. Therefore, the objective of the present study was to evaluate the compatibility of ITZ with BNZ and with selected pharmaceutical excipients. Differential scanning calorimetry (DSC), derivative thermogravimetry (DTG), Fourier transform infrared spectroscopy (FTIR), optical microscopy and kinetic analyses under isothermal conditions were performed. The results showed thermal interactions between ITZ and the excipients hydroxypropyl methylcellulose and polyvinylpyrrolidone. The FTIR data together with complementary tests revealed signs of drug decomposition in the presence of these materials. Thus, these excipients were considered incompatible with ITZ and should be avoided in solid dosage forms containing this drug. Moreover, it was found that associations between ITZ and BNZ are potentially unstable. Therefore, it is necessary to develop a pharmaceutical dosage form that avoids the processing of these drugs together and allows a stable pharmaceutical formulation to be obtained.
    Thermochimica Acta 01/2014; 575:29–33. · 1.99 Impact Factor
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    ABSTRACT: The purpose of this work was the development of a multicompartimental nanocarrier for the simultaneous encapsulation of paclitaxel (PTX) and genistein (GEN), associating antiangiogenic and cytotoxic properties in order to potentiate antitumoral activity. Polymeric nanocapsules containing PTX were obtained by interfacial deposition of preformed polymer and coated with a phospholipid bilayer entrapping GEN. Physical-chemical and morphological characteristics were characterized, including size and size distribution, drug entrapment efficiency and drug release profile. In vivo studies were performed in EAT bearing Swiss mice. Entrapment efficiency for both drugs in the nanoparticles was approximately 98%. Average particle diameter was 150 nm with a monomodal distribution. In vitro assays showed distinct temporal drug release profiles for each drug. The dose of 0.2 mg/kg/day of PTX resulted in 11% tumor inhibition, however the association of 12 mg/kg/day of GEN promoted 44% tumor inhibition and a 58% decrease in VEGF levels. Nanoparticles containing GEN and PTX with a temporal pattern of drug release indicated that the combined effect of cytotoxic and antiangiogenic drugs present in the formulation contributed to the overall enhanced antitumor activity of the nanomedicine.
    Pharmaceutical Research 10/2013; · 4.74 Impact Factor
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    ABSTRACT: Enalapril maleate (EM) is a widely used anti-hypertensive drug which is unstable when mixed with excipients. Enalaprilate and diketopiperazine (DPK) are the main degradation products of enalapril. The in situ preparation of enalapril sodium salt (NaE) has been used to improve drug stability in dosage forms; however, gas release and product rejection ensue when the chemical reaction for obtaining the sodium salt is not completely finished before packaging. This study evaluated the effect of stearic acid (SA) on enalapril stability in microcrystalline cellulose (MCC) pellets containing EM or NaE. MCC pellets containing SA were prepared by the extrusion-spheronization technique and characterized. Enalapril stability and dissolution were then evaluated. DPK and enalaprilate formation were reduced by the addition of SA in pellets containing EM. The overall enalapril degradation in these formulations was lower when compared with pellets containing EM or even NaE prepared without SA. The immediate-release characteristic was maintained by the addition of 5% crospovidone to all the formulations tested. The incorporation of SA into NaE pellets resulted in unexpected enalapril degradation, caused by the interaction of these compounds, as suggested by a thermal analysis of the SA-NaE binary mixture. The findings presented here showed that formulations containing SA could substitute the formation of NaE, since they provide better enalapril stability in solid dosage forms. In addition, it is suggested that the stabilization effects would be observed for other N-carboxyalkyl dipeptide analogs with angiotensin converting enzyme inhibition activity, since these new entities share the same degradation pathway of enalapril.
    AAPS PharmSciTech 07/2013; · 1.58 Impact Factor
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    ABSTRACT: The isoflavone genistein (GEN) is a natural product with potential applications for skin cancer treatment and chemoprevention; however its high lipophilicity and chemical instability limits its clinical use. Therefore, attempts towards protecting GEN against degradation and increasing its penetration in the skin might be a valid approach. In this work, GEN loaded-PLA nanocapsules (GEN-NC) were prepared by interfacial deposition of preformed polymer (nanoprecipitation); physicochemical characterization and stability studies for 90 days were conducted. GEN-NC were incorporated into semi-solid formulations and permeation experiments were carried out using porcine ear skin. GEN-NC optimized formulation presented a mean diameter of 139 +/- 7.31 nm, polydispersity index of 0.128 +/- 0.08, encapsulation efficiency of 89.63 +/- 2.27% and drug loading from 0.6 to 1.4 w/w%. Stability studies demonstrated that nanocapsules did not exhibit aggregation during the 90 days of the assay, however, a drop in encapsulation efficiency was observed in the first 10 days. Permeation experiments demonstrated that a higher amount of GEN reaches deeper layers of the skin and increased penetration was achieved when GEN-NC were incorporated in a semi-solid gel formulation, indicating that GEN-NC might be a promising nanocarrier system for skin delivery of GEN.
    Journal of Biomedical Nanotechnology 03/2013; 9(3):527-34. · 5.26 Impact Factor
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    ABSTRACT: Genistein (GEN) has potential advantages for topical skin delivery, but no literature data is available for its quantitation in different skin layers, such as the stratum corneum (SC). Therefore, a simple, rapid, selective and sensitive bioanalytical method was developed and validated for GEN quantitation in porcine skin samples following in vitro permeation studies. GEN was assayed by HPLC with UV-vis detection (270<4>nm) using 0.5% acetic acid in water / n-propanol / acetonitrile (50:2:48 v/v/v) as mobile phase (flow-rate of 1.0<4>mL/min). Specificity was demonstrated since endogenous skin components did not interfere with GEN peak. Standard analytical curve was linear over the concentration range (0.1 - 60 µg/mL) and the lower limit of quantitation was determined for different skin layers (100<4>ng/mL). GEN recovery from skin layers ranged from 95.57 to 97.57%. Permeation studies were carried out using an automated vertical diffusion cell apparatus. No fluctuation on the amount of GEN retained in the SC was observed over time, but increasing amounts of the drug were found in deeper layers of the skin. The method was reliable and reproducible for the quantitation GEN in skin samples enabling the determination of the cutaneous penetration profile of this drug in permeation experiments.
    Biological & Pharmaceutical Bulletin 08/2012; · 1.85 Impact Factor
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    ABSTRACT: Pseudomonas aeruginosa is an opportunistic microorganism with the ability to respond to a wide variety of environmental changes, exhibiting a high intrinsic resistance to a number of antimicrobial agents. This low susceptibility to antimicrobial substances is primarily due to the low permeability of its outer membrane, efflux mechanisms and the synthesis of enzymes that promote the degradation of these drugs. Cephalosporins, particularty ceftazidime and cefepime are effective against P. aeruginosa, however, its increasing resistance has limited the usage of these antibiotics. Encapsulating antimicrobial drugs into unilamellar liposomes is an approach that has been investigated in order to overcome microorganism resistance. In this study, antimicrobial activity of liposomal ceftazidime and cefepime against P. aeruginosa ATCC 27853 and P. aeruginosa SPM-1 was compared to that of the free drugs. Liposomal characterization included diameter, encapsulation efficiency and stability. Minimum Inhibitory Concentration (MIC) was determined for free and liposomal forms of both drugs. Minimum Bactericidal Concentration (MBC) was determined at concentrations 1, 2 and 4 times MIC. Average diameter of liposomes was 131.88 nm and encapsulation efficiency for cefepime and ceftazidime were 2.29% end 5.77%, respectively. Improved stability was obtained when liposome formulations were prepared with a 50% molar ratio for cholesterol in relation to the phospholipid. MIC for liposomal antibiotics for both drugs were 50% lower than that of the free drug, demonstrating that liposomal drug delivery systems may contribute to increase the antibacterial activity of these drugs.
    Brazilian Journal of Microbiology 07/2012; 43(3):984-92. · 0.76 Impact Factor
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    ABSTRACT: The objective of this study was to develop nanocapsules and nanospheres of polylactide-co-glycolide (PLGA) containing magnetic nanoparticles and rapamycin. Magnetic nanoparticles (MP) were obtained by the co-precipitation of Fe(ll) and Fe(III) salts by addition of ammonium hydroxide. Nanocapsules (NC) and nanospheres (NS) containing either uncoated magnetic nanoparticles (MP), MP coated with oleic acid monolayer (MPOA) or MP coated with oleic acid bilayer (MPOA-OA) were prepared by the emulsion evaporation method. Rapamycin was also encapsulated into NC and NS. Morphology, size, size distribution, entrapment efficiency, stability and magnetization characteristics were determined. Non-contact AFM images showed that the composite nanoparticles were almost spherical in shape. The resulting polymeric nanocarriers were found to have a mean diameter of approximately 120 nm with a narrow size distribution. The influence of some experimental parameters on the entrapment efficiency and stability was determined. Nanocapsules and nanospheres prepared with uncoated magnetic nanoparticles exhibited higher entrapment efficiency and stability. Superparamagnetic behavior of the magnetic nanocomposite was demonstrated by magnetization data. These findings may contribute to the development of potential controlled release drug targeting devices based on magnetic polymeric nanocarriers.
    Journal of Biomedical Nanotechnology 04/2012; 8(2):193-201. · 5.26 Impact Factor
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    ABSTRACT: Pothomorphe umbellata (L.) Miq. is a Brazilian shrub with therapeutic and economic applications. There are some reports on the technological development of P. umbellata preparations; however, there are no studies on the influence of non-conventional extraction procedures on the quality of P. umbellata extracts. The aim of this study was to evaluate the effects of the ultrasound-assisted extraction (UE) parameters upon the extraction yield (EY%) of 4-nerolidylcatechol (4-NC) and the antioxidant activity of P. umbellata extracts using a factorial design and response surface methodology. Extracts obtained by UE and percolation were compared, and the photostability of 4-NC was evaluated via the exposure of UVA and visible light to the samples. The most influential variables observed for the UE were the ethanol-to-water and drug-to-solvent ratios. UE improved the extraction kinetics of 4-NC from plant material and improved the antioxidant activity of the extracts. Some of the ultrasound extracts showed an antioxidant activity that was not proportional to their 4-NC concentration, which suggests the presence of other active antioxidant compounds in these P. umbellata extracts. There was no significant difference in the photostability of 4-NC between the percolated and ultrasound extracts. Surprisingly, the isolated 4-NC material was significantly more stable when exposed to UVA-visible light compared to 4-NC in the plant extracts.
    Ultrasonics Sonochemistry 09/2011; 18(5):1002-7. · 3.52 Impact Factor
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    ABSTRACT: Ketoprofen is a non-steroid anti-inflammatory drug (NSAID) used in the treatment of rheumatic diseases and in mild to moderate pain. Ketoprofen has a short biological half-life and the commercially available conventional release formulations require dosages to be administered at least 2-3 times a day. Due to these characteristics, ketoprofen is a good candidate for the preparation of controlled release formulations. In this work, a multiparticulate-sustained release dosage form containing ketoprofen in a carnauba wax matrix was developed. Particles were prepared by an emulsion congealing technique. System variables were optimized using fractional factorial and response surface experimental design. Characterization of the particles included size and morphology, flow rate, drug loading and in vitro drug release. Spherical particles were obtained with high drug load and sustained drug release profile. The optimized particles had an average diameter of approximately 200 µm, 50% (w/w) drug load, good flow properties and prolonged ketoprofen release for more than 24 h. Carnauba wax microspheres prepared in this work represent a new multiparticulate-sustained release system for the NSAID ketoprofen, exhibiting good potential for application in further pharmaceutical processes.
    Drug Development and Industrial Pharmacy 06/2011; 38(1):1-11. · 1.54 Impact Factor
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    ABSTRACT: Topotecan is an important cytotoxic drug that has gained broad acceptance in clinical use for the treatment of refractory ovarian and small-cell lung cancer. The lactone active form of topotecan can be hydrolyzed in vivo, decreasing the drug's therapeutic efficacy. Lipid encapsulation may promote in vivo stabilization by removing topotecan from aqueous media. Earlier reports of topotecan lipid nanoencapsulation have focused on liposomal encapsulation; however, the higher stability and cost-effectiveness of solid lipid nanoparticles (SLN) highlight the potential of these nanoparticles as an advantageous carrier for topotecan. The initial motivation for this work was to develop, for the first time, solid lipid nanoparticles and nanostructured lipid carriers (NLC) with a high drug loading for topotecan. A microemulsion technique was employed to prepare SLNs and NLCs and produced homogeneous, small size, negatively charged lipid nanoparticles with high entrapment efficiency and satisfactory drug loading. However, low recovery of topotecan was observed when the microemulsion temperature was high and in order to obtain high quality nanoparticles, and precise control of the microemulsion temperature is critical. Nanoencapsulation sustained topotecan release and improved its chemical stability and cytotoxicity. Surprisingly, there were no significant differences between the NLCs and SLNs, and both are potential carriers for topotecan delivery.
    European journal of pharmaceutics and biopharmaceutics: official journal of Arbeitsgemeinschaft fur Pharmazeutische Verfahrenstechnik e.V 02/2011; 79(1):189-96. · 3.15 Impact Factor
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    ABSTRACT: Preclinical investigations can start with preliminary in vitro studies before using animal models. Following this approach, the number of animals used in preclinical acute toxicity testing can be reduced. In this study, we employed an in-house validated in vitro cytotoxicity test based on the Spielmann approach for toxicity evaluation of the lignan grandisin, a candidate anticancer agent, and its major metabolite, the 4-O-demethylgrandisin, by neutral red uptake (NRU) assay, on mouse fibroblasts Balb/c 3T3 cell line. Using different concentrations of grandisin and its major metabolite (2.31; 1.16; 0.58; 0.29; 0.14; 0.07; 0.04; 0.002 μM) in Balb/c 3T3-A31 NRU cytotoxicity assay, after incubation for 48 h, we obtained IC(50) values for grandisin and its metabolite of 0.078 and 0.043 μM, respectively. The computed LD(50) of grandisin and 4-O-demethylgrandisin were 617.72 and 429.95 mg/kg, respectively. Both were classified under the Globally Harmonized System as category 4. Since pharmacological and toxicological data are crucial in the developmental stages of drug discovery, using an in vitro assay we demonstrated that grandisin and its metabolite exhibit distinct toxicity profiles. Furthermore, results presented in this work can contribute to reduce the number of animals required in subsequent pharmacological/toxicological studies.
    Experimental and toxicologic pathology: official journal of the Gesellschaft fur Toxikologische Pathologie 05/2010; 63(5):505-10. · 1.43 Impact Factor
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    ABSTRACT: Objectives The antitumoural properties of grandisin, a tetrahydrofuran neolignan from Piper solmsianum, were investigated by in-vitro and in-vivo assays using the Ehrlich ascites tumoural (EAT) model.Methods Viability of the tumour cells was evaluated by Trypan blue exclusion and MTT methods, after incubation with grandisin (0.017-2.3 μM). The effects of grandisin on the activity of caspase-3, −6, −8, and −9 were also investigated using colorimetric protease kits. In-vivo studies were performed in EAT-bearing mice treated intraperitoneally with 2.5, 5 or 10 mg/kg grandisin for 10 days.Key findings Grandisin inhibited the growth of EAT cells, by both methods, with IC50 values less than 0.25 μM. The results showed that the activity of all the caspases studied increased in grandisin-treated cells, when compared with control, non-treated cells. Administering grandisin to EAT-bearing mice increased survival of the animals, in a dose-dependent manner. Simultaneously, we detected a 66.35% reduction of intraperitoneal tumour cell burden in the animals treated with 10 mg/kg grandisin. Additionally, in these animals, the marked increase of vascular endothelial growth factor (VEGF) levels, induced by EAT development, was decreased with treatment with grandisin, resulting in a reduction of 32.1% of VEGF levels in the peritoneal washing supernatant, when compared with the control.Conclusions The results demonstrated that grandisin induced in-vitro cytotoxicity and antiangiogenic effects in mice while it acted against tumour evolution, prolonging host survival.
    Journal of Pharmacy and Pharmacology. 01/2010; 61(12):1709 - 1714.
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    ABSTRACT: The antitumoural properties of grandisin, a tetrahydrofuran neolignan from Piper solmsianum, were investigated by in-vitro and in-vivo assays using the Ehrlich ascites tumoural (EAT) model. Viability of the tumour cells was evaluated by Trypan blue exclusion and MTT methods, after incubation with grandisin (0.017-2.3 microm). The effects of grandisin on the activity of caspase-3, -6, -8, and -9 were also investigated using colorimetric protease kits. In-vivo studies were performed in EAT-bearing mice treated intraperitoneally with 2.5, 5 or 10 mg/kg grandisin for 10 days. Grandisin inhibited the growth of EAT cells, by both methods, with IC50 values less than 0.25 microm. The results showed that the activity of all the caspases studied increased in grandisin-treated cells, when compared with control, non-treated cells. Administering grandisin to EAT-bearing mice increased survival of the animals, in a dose-dependent manner. Simultaneously, we detected a 66.35% reduction of intraperitoneal tumour cell burden in the animals treated with 10 mg/kg grandisin. Additionally, in these animals, the marked increase of vascular endothelial growth factor (VEGF) levels, induced by EAT development, was decreased with treatment with grandisin, resulting in a reduction of 32.1% of VEGF levels in the peritoneal washing supernatant, when compared with the control. The results demonstrated that grandisin induced in-vitro cytotoxicity and antiangiogenic effects in mice while it acted against tumour evolution, prolonging host survival.
    The Journal of pharmacy and pharmacology. 12/2009; 61(12):1709-14.
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    ABSTRACT: Enalapril maleate, available on the market in a variety of different pharmaceutical formulations, is commonly used for the control of systemic arterial hypertension. Many therapeutical failures have been reported thus far in clinical practice with respect to switching between different pharmaceutical formulations of the same product during pharmacological therapy. In the present study, plasma concentrations of enalapril and enalaprilate were measured in hypertensive patients undergoing treatment with different pharmaceutical formulations. Materials and methods: Pharmaceutical formulations studied included the reference brand product, a generic formulation, and a third drug product marketed as "similar"; plasma samples were obtained from 30 hypertensive volunteer patients. Drug was extracted from the plasma by solid phase extraction and determined by liquid chromatography-tandem mass spectrometry. The method was validated for the main analytical parameters. Results: The analytical method developed in this study, using liquid chromatography-tandem mass spectrometry, was confirmed as suitable for application in the determination of plasma concentrations in patients and subsequently revealed statistically significant differences in plasma concentrations between the 3 treatment groups. Conclusions: Such differences reinforce the hypothesis that the bioequivalence tests currently proposed by the regulatory authorities to promote interchangeability between pharmaceutical formulations may not in fact represent a definitive parameter for guaranteeing similar plasma concentrations.
    Therapeutic drug monitoring 09/2009; 31(6):710-6. · 2.43 Impact Factor
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    ABSTRACT: Magnetoliposomes consist of vesicles composed of a phospholipid membrane encapsulating magnetic nanoparticles. These systems have several important applications, such as in MRI contrast agents, drug and gene carriers, and cancer treatment devices. For all of these applications, controlling the number of encapsulated magnetic nanoparticles is a key issue. In this work, we used a magneto-optical technique to obtain information about the efficiency of encapsulation, the number of nanoparticles encapsulated per liposome and also about the formation of the nanoparticle structures. The parameters studied included the effect of the duration of sonication, the presence of cholesterol in the liposome membrane, as well as time-related stability. For the liposomal vesicles prepared in this work, we found between 35 and 300 nanoparticles encapsulated per liposome, depending on the experimental conditions, consisting of small linear chains of nanoparticles, basically trimers and tetramers. The methodology developed might be useful for the investigation and improvement of the properties of several magnetic nanocarrier systems.
    Nanotechnology 02/2009; 20(4):045103. · 3.84 Impact Factor
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    ABSTRACT: Stability of enalapril maleate formulations can be affected when the product is exposed to higher temperature and humidity, with the formation of two main degradation products: enalaprilat and a diketopiperazine derivative. In this work, stability and drug release profiles of 20 mg enalapril maleate tablets (reference, generic and similar products) were evaluated. After 180 days of the accelerated stability testing, most products did not exhibit the specified amount of drug. Additionally, drug release profiles were markedly different from that of the reference product, mainly due to drug degradation. Changes in drug concentration and drug release profile of enalapril formulations are strong indicators of a compromised bioavailability, with possible interferences on the therapeutic response for this drug.
    Journal of Pharmaceutical and Biomedical Analysis 09/2008; 47(4-5):934-7. · 2.95 Impact Factor
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    ABSTRACT: A liquid chromatography (LC) method was developed and validated for identification and quantification of polyphenols in aqueous extractive solution from Ilex paraguariensis (erva‐mate), in agreement with the ICH requirements for analytical methods. The analysis was performed using a RP 18 column, in gradient solvent. Chlorogenic acid (CLOA) and rutin (RU) were used as external standards. The standard curves for CLOA and RU were linear with correlation coefficients higher than 0.9980. The LC method showed excellent performance in separating seven peaks. The method showed excellent repeatability (R.S.D.
    Journal of Liquid Chromatography &amp Related Technologies 01/2007; 30(20):3119-3131. · 0.57 Impact Factor
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    ABSTRACT: This paper describes the development of a gas chromatography (GC) method used for the assay of isotretinoin in its isolated form and in pharmaceutical formulations. Isotretinoin soft and hard gelatin capsules were prepared with various excipients. The performance of the proposed gas chromatography method was compared to that of traditional high performance liquid chromatography (HPLC) systems for this substance, and the GC parameters were established based on several preliminary tests, including thermal analysis of isotretinoin. Results showed that gas chromatography-flame ionization detector (GC-FID) exhibited a separation efficiency superior to that of HPLC, particularly for separating isotretinoin degradation products. This method was proven to be effectively applicable to stability evaluation assays of isotretinoin and isotretinoin based pharmaceuticals.
    Journal of Pharmaceutical and Biomedical Analysis 08/2005; 38(4):678-85. · 2.95 Impact Factor
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    ABSTRACT: A isotretinoína, quimicamente conhecida como ácido-13-cis-retinóico, faz parte do amplo grupo de compostos relacionados à vitamina A. É empregada particularmente no tratamento da acne cística e nodular e como inibidor da proliferação de células neoplásicas, por exercer efeito regulador sobre a diferenciação celular. Os efeitos adversos envolvendo o uso de isotretinoína estão relacionados à pele e membranas mucosas, sistemas nervoso, músculo esquelético, linfático, gastrintestinal, cardiorespiratório e geniturinário. A isotretinoína é um composto termo e fotossensível e, por assim se apresentar, desperta o interesse pelo estudo de sua estabilidade, empregando-se para isso várias metodologias analíticas como a CLAE, CG, análise térmica, espectroscopia de massa, microcalorimetria, difratometria de raios-X e muitas outras que devem ser selecionadas de acordo com o interesse do pesquisador.
    Revista Brasileira de Ciências Farmacêuticas 12/2002; 38(4):415-430.
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    ABSTRACT: A utiliza»c~ao de nanoestruturas magneticas no carreamento de drogase certamente uma das aplica»c~oes mais interessantes da Nanotecnologia. Neste caso temos uma aplica»c~ao de medicamentos local utilizando vetores espec¶‡flcos, como por exemplo, acoplando anticorpos a moleculas adsorvidas na superf¶‡cie de nanopart¶‡culas, ou ainda, utilizando gradiente de campo magnetico numa posi»c~ao espec¶‡flca do corpo do paciente. Esse tipo de estrategia conta com a possibilidade de uso de menor quantidade de medicamentos, e portanto, espera-se pouca ou a completa aus^encia de efeitos colaterais. Um dos sistemas de grande interesse hoje em diae o magnetolipossoma, que consiste de nanopart¶‡culas magneticas encapsuladas dentro de lipossomas. Os magne- tolipossomas t^em sido utilizados tanto no diagnostico de doen»cas, como agentes de contraste no imageamento por resson^ancia magnetica nuclear (RMNI) ou tomografla computadorizada, quanto no tratamento via o pro- cesso de magnetohipertermia (aquecimento local via a»c~ao de campo magnetico ac) ou libera»c~ao controlada de farmacos. Neste trabalho estudamos as propriedades magnetoopticas de magnetolipossomas por meio da tecnica de birrefring^encia magnetica (BME).(2-4) Os magnetolipossomas possuem nanopart¶‡culas de magnetita recobertas com carboxildextran no interior dos lipossomas. As nanopart¶‡culas magneticas foram caracterizadas por meio de TEM. A polidispers~ao dos magnetolipossomase obtida utilizando a tecnica de espalhamento de luz. Em particular fomos capazes, por meio da tecnica de birrefring^encia magnetica estatica instalada no In- stituto de F¶‡sica da UFG, de quantiflcar o numero de nanopart¶‡culas magneticas encapsuladas nos lipossomas. Investigamos tambem a estabilidade e libera»c~ao de nanopart¶‡culas em fun»c~ao do tempo utilizando lipossomas recobertos com diferentes quantidades de colesterol e diferentes quantidades de part¶‡culas magneticas. Estas informa»c~oes s~ao de grande import^ancia para as aplica»c~oes biomedicas dos magnetolipossomas, por exemplo, no carreamento local de medicamentos ou ainda como agentes de contraste em RMNI. 1. A. Ito, H. Honda, T. Kobayashi, Cancer Immunol. Immunother. 55, 320 (2006) 2. G.D. Benicio, F. Pelegrini, K.L.C. Miranda, P.P.C. Sartoratto, A.F. Bakuzis, J. Appl. Phys. 101, 09J106 (2007).

Publication Stats

51 Citations
105 Downloads
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45.79 Total Impact Points

Institutions

  • 2002–2014
    • Universidade Federal de Goiás
      • • Instituto de Física (IF)
      • • Faculdade de Farmácia (FF)
      Goianá, Goiás, Brazil