Time filter

Source Type

Bunaciu A.A.,Research Center for Instrumental Analysis | Danet A.F.,University of Bucharest | Fleschin S.,University of Bucharest | Aboul-Enein H.Y.,Pharmaceutical and Drug Industries Research Division
Critical Reviews in Analytical Chemistry | Year: 2016

This review presents some of the most recent aspects related to antioxidants and the basic kinetic models of inhibited autoxidation and analyzes the chemical principles of antioxidant capacity assays. Taking into account the reactions involved, in the antioxidant activity determinations, the assays can be classified into two main types: hydrogen atom transfer reactions and electron transfer. This review focuses on analytical methods used for antioxidant activity assay, published in the period 2009–2014. © 2016 Taylor & Francis Group, LLC Source

Tamba B.I.,Grigore T. Popa University of Medicine and Pharmacy | Dondas A.,Grigore T. Popa University of Medicine and Pharmacy | Leon M.,Grigore T. Popa University of Medicine and Pharmacy | Neagu A.N.,Al. I. Cuza University | And 4 more authors.
European Journal of Pharmaceutical Sciences | Year: 2015

Background: The current progress in pharmaceutical nanotechnology field has been exploited in the design of functionalized radiolabelled nanoparticles that are able to deliver radionuclides in a selective manner to improve the outcome of diagnosis and treatment. Silica nanoparticles (SNPs) have been widely developed for biomedical applications due to their high versatility, excellent functional properties and low cost production, with the possibility to control different topological parameters relevant for multidisciplinary applications.Purpose: The aim of the present study was to characterize and evaluate both in vitro, by microscopy techniques and in vivo, by scintigraphic imaging, the biodistribution of silica nanostructures derivatives (Cy5.5 conjugated SNPs and 99mTc radiolabelled SNPs) to be applied as radiotracers in biomedicine. Methods: SNPs were synthesized by hydrolysis and condensation of silicon alkoxides, followed by surface functionalization with amino groups available for fluorescent dye and radiolabelling possibility.Results: Our data showed the particles size distribution (200350 nm), the surface charge (negative for bare and fluorescent SNPs and positive for amino SNPs), polydispersity index (broad distribution), the qualitative composition and the toxicity assessments (safe material) that made the obtained SNPs candidates for in vitro/in vivo studies. A high uptake of fluorescent SNPs in all the investigated organs was evidenced by confocal microscopy. The 99mTc radiolabelled SNPs biodistribution was quantified in the range of 12-100% counts/g organ using the scintigraphic images.Conclusions: The obtained results reveal improved properties, namely, reduced toxicity with a low level of side effects, an improved biodistribution, high labelling efficiency and stability of the radiolabelled SNPs with potential to be applied in biomedical science, particularly in nuclear medicine as a radiotracer. © 2015 Elsevier B.V. All rights reserved. Source

Dodi G.,Technical University Gheorghe Asachi | Dodi G.,Research Center for Instrumental Analysis | Pala A.,University of Sassari | Barbu E.,University of Portsmouth | And 4 more authors.
Materials Science and Engineering C | Year: 2016

Carboxymethyl guar gum (CMGG) synthesized from commercially available polysaccharide was formulated into nanoparticles via ionic gelation using trisodium trimetaphosphate (STMP) as cross-linking agent. Characterisation using a range of analytical techniques (FTIR, NMR, GPC, TGA and DLS) confirmed the CMGG structure and revealed the effect of the CMGG and STMP concentration on the main characteristics of the obtained nanoformulations. The average nanoparticle diameter was found to be around 208 nm, as determined by dynamic light scattering (DLS) and confirmed by scanning electron microscopy (SEM) and nanoparticle tracking analysis (NTA). Experiments using simulated gastric and intestinal fluids evidenced significant pH-dependent drug release behaviour of the nanoformulations loaded with Rhodamine B (RhB) as a model drug (loading capacity in excess of 83%), as monitored by UV-Vis. While dose-dependent cytotoxicity was observed, the nanoformulations appeared completely non-toxic at concentrations below 0.3 mg/mL. Results obtained so far suggest that carboxymethylated guar gum nanoparticles formulated with STMP warrant further investigations as polysaccharide based biocompatible drug nanocarriers. © 2016 Elsevier B.V. All rights reserved. Source

Draganescu D.,Technical University Gheorghe Asachi | Draganescu D.,Aurel Vlaicu University | Ibanescu C.,Technical University Gheorghe Asachi | Tamba B.I.,Grigore T. Popa University of Medicine and Pharmacy | And 4 more authors.
International Journal of Biological Macromolecules | Year: 2015

Flaxseed lignans are a natural source of useful biologically active components that show a diverse spectrum of health-promoting properties. The valuable effects of the phenolic molecules are mainly due to their antioxidant activity by preventing oxidative stress and stimulate collagen synthesis, therefore, providing benefits to the skin. The present work highlights the development of flaxseed extract formulation as novel wound healing agent. The recognition of key structural features within flaxseed extract was crucial for the design and development of the therapeutic cream. Chromatographic analyses were employed for bioactive compounds identification and quantification. Folin-Ciocalteu method determined the total phenolic content and the antioxidant properties were evaluated by DPPH assay. The storage and loss modulus and tan. δ were calculated for cream rheological properties evaluation. In vitro diffusion capacity and in vivo wound healing activity of phenolic cream were evaluated on Wistar rats. The collective properties and healing effect of the flaxseed suggested wound healing capacity. © 2014 Elsevier B.V. Source

Bunaciu A.A.,Research Center for Instrumental Analysis | Fleschin S.,University of Bucharest | Aboul-Enein H.Y.,Pharmaceutical and Drug Industries Research Division
Revue Roumaine de Chimie | Year: 2015

Fourier transform infrared spectroscopy (FTIR) is a fast and nondestructive analytical method. The infrared spectrum of a mixture serves as the basis to quantitate its constituents, and a number of common clinical chemistry tests have proven to be feasible using this approach. This mini-review provides some background to infrared spectroscopy including Fourier transform infrared spectroscopy in biological fluids. By this we provide the reader with sufficient background for selected applications in cancer diagnostic. This review focuses on biomedical FTIR applications, published in the period 2009-2014, used for early detection of cancer through qualitative and quantitative analysis. Source

Discover hidden collaborations