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Journal of Thermal Analysis and Calorimetry
Authors: Mariam Khvedelidze, Tamaz Mdzinarashvili, Tamar Partskhaladze, Noha Nafee, Ulrich Schaefer, Claus-Michael Lehr, and Marc Schneider

Abstract  

The calorimetric investigation of non-coated and chitosan-coated PLGA nanoparticles (NP) shows that at initial temperatures of heating particle swelling takes place what results in an internal architectural change at lower than physiological temperature. It has shown that the temperature of NP tightness perturbing depends on solvent polarity: as more polar is the solvent more stable are particles. The break of existing bonds in NP shell is accompanied with heat absorption peak which undergoes significant changes depending on heating rate. In the wide pH 2–8 interval in transition temperature no changes occurred. The obtained results show that such NP could be used in acidic area for drug transfer, which gives possibility to take medicine orally. It was shown that DNA attaches only to chitosan-coated NP. The optimal ratio for DNA loading onto the NP was found to be 7:1 (WNP/WDNA).

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It remains difficult to distinguish adenoid cystic carcinoma (ACC) from polymorphous low-grade adenocarcinoma (PLGA). Although these neoplasms exhibit nearly similar histologic patterns, their biologic behavior is significantly different. This study was carried out in an attempt to overcome the histological overlap between these tumors using immunohistochemical method for c-kit and galectin-3 proteins on twenty cases of salivary gland tumors including twelve ACC and eight PLGA. Results revealed positive cytoplasmic reactivity for c-kit in 100% of ACC cases and only in 25% of PLGA. On the other hand, galectin-3 expression was observed in 100% of both ACC and PLGA cases. Moreover, solid variant of ACC showed overexpression of both proteins than cribriform and tubular subtypes. Significant positive correlation between the two studied proteins in ACC and PLGA was also observed (p < 0.05). Upon these results, over expression of c-kit and galectin-3 in ACC cases supports the concept of solid variant as a high-grade tumor. Moreover, c-kit may be used as a helpful marker to distinguish ACC from PLGA in cases where the diagnosis can be challenging.

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Journal of Flow Chemistry
Authors: Alfonso Gañán-Calvo, Elena Castro-Hernández, María Flores-Mosquera, and Lucía Martín-Banderas

Massive, nearly monodisperse, true microencapsulation of a wide variety of active ingredients within biocompatible shells can be achieved using flow focusing at moderate-high Reynolds numbers, a paradigmatic tool for highly controlled flow chemistry processes whose flexibility and physical aspects are briefly illustrated here. We show that the natural, regular capillary breakup of a laminar high-speed microjet produced by gentle mechanical means alone allows the production of true microcapsules with controlled dimensions. The process versatility is shown in a variety of examples including encapsulation of different materials as proteins and/or microorganisms in biocompatible polymers as poly-l-glutamic acid (PLGA). Microcapsules produced show nearly homogeneous size, well-centered core, and their size and structure are well predicted by simple theoretical models.

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A simple, sensitive, precise, rapid, and reliable high-performance thin-layer chromatographic (HPTLC) method for the simultaneous estimation of sparfloxacin (SPF) and flurbiprofen (FLB) in bulk drug as well as in dual drug loaded poly-(lactic-co-glycolic acid) (PLGA) nanoparticles was developed. In this method, aluminumbacked silica gel 60 F254 plates (20 × 10 cm: 200 μm thickness) were used as stationary phase and chloroform-methanol-formic acid (7.5:1:1, v/v) as an optimized mobile phase. Developed chromatogram was scanned at 258 nm, the wavelength of maximum absorption SPF and FLB. Regression analysis of the calibration data showed an excellent linear relationship between peak area versus drug concentration. Linearity was found to be in the range of 100–600 ng spot−1 and 40–800 ng spot−1 for SPF and FLB, respectively. The suitability of the developed HPTLC method for simultaneous estimation of SPF and FLB was established by validating it as per the ICH guidelines. The limits of detection (LOD) and quantification (LOQ) for SPF were found to be ≈13 and ≈40 ng spot−1, respectively, and those for FLB ≈27 ng spot−1 and ≈82 ng spot−1, respectively. The developed method was found to be linear (r 2 = 0.999), precise (% RSD < 1.5% repeatability and <2.55% for intermediate precision), accurate (mean recovery of within the range of 98–102%), specific, and robust. Stress-induced degradation studies revealed the suitability of method for the quantitative determination of drugs in the presence of degradants. The developed method has been successfully applied for the determination of entrapment efficiency, drug loading, in vitro drug release profile and stability assessment of dual drug loaded PLGA nanoparticles (NPs).

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Interventional Medicine and Applied Science
Authors: Kamal Dua, Shakti Dhar Shukla, Terezinha de Jesus Andreoli Pinto, and Philip Michael Hansbro

. Similarly, another study has shown reduced lung inflammation in murine models of obstructive lung diseases using the PEGylated immunoconjugated poly(lactic-co-glycolic acid) (PLGA) NP containing non-steroidal anti-inflammatory drug (ibuprofen) by targeting

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Interventional Medicine and Applied Science
Authors: Anand Maurya, Anurag Kumar Singh, Gaurav Mishra, Komal Kumari, Arati Rai, Bhupesh Sharma, Giriraj T. Kulkarni, and Rajendra Awasthi

Water solubility of curcumin was increased about 640-fold relative to pure curcumin. Oral bioavailability was increased 5.6-fold for longer duration compared with that of pure curcumin – PLGA [ 7

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R. Herrero-Vanrell P. Pastoriza 2006 Radiosterilization of indomethacin PLGA/PEG-derivative microspheres: Protective effects of low temperature

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Acta Physiologica Hungarica
Authors: Teodora Mocan, S. Clichici, L. Agoşton-Coldea, L. Mocan, Ş Şimon, I. Ilie, A. Biriş, and Adriana Mureşan

567 Reddy MK, Wu L, Kou W, Ghorpade A, Labhasetwar V: Superoxide-dismutase-loaded PLGA nanoparticles protect cultured human neurons under oxidative stress. Appl. Biochem

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32 42 Nafee, N., Taetz, S., Schneider, M. és mtsai: Chitosan-coated PLGA nanoparticles for DNA/RNA delivery: effect of the formulation parameters on complexation

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, 7 (1), 71–86. 37 Fornaguera, C., Dols-Perez, A., Calderó, G., et al.: PLGA nanoparticles prepared by nano-emulsion templating using low-energy methods as

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