Objective(s):Cefixime (Cfx), is a semi-synthetic third-generation oral cephalosporin antibiotic that is prescribed for the treatment of susceptible infections. There are some procedures for the determination of Cfx in pharmaceutical formulations and biological samples. Herein a spectrofluorimetric method was proposed for Cfx determination based on the fluorescence quenching of terbium-danofloxa...

Background: The rapid increase of HIV-1 strains resistant to current antiretroviral drugs is a challenge for successful AIDS therapy. This necessitates the development of novel drugs, and to this end, availability of screening systems for in vitro drug discovery is a priority. Herein, we report the modification of a previously developed system for increased sensitivity, ease of use, and cost-ef...

To explore the function of light-harvesting complex protein (LHCP) in Arabidopsis growth and development, the Leclere and Bartel seed collection was screened. In this collection randomly cloned cDNAs are expressed under the CaMV35S promoter. A pale green line has been identified and characterized in more details. Analysis of the inserted cDNA in the pale green line showed it encodes LHCB1 prote...

A novel quaternary ammonium-based cationic gemini surfactant (S6) having 1,6 di-bromo hexane as a spacer, have been used and its interaction with insulin in aqueous solution (pH, 7.40) was investigated by several methods including fluorescence spectroscopy, UV-Vis spectroscopy, circular dichroism, dynamic light scattering, ζ-potential measurements, conductivity and transmission electron microsc...

Objective(s): The interaction of DNA with iron oxide nanoparticles (SPIONs) was studied to find out the interaction mechanism and design new drug delivery systems. Materials and Methods: The interaction of calf thymus DNA (ctDNA) with SPIONs doped with 2H-chromene via dopamine as cross linker (SPIONs@DA-Chr) was studied using the UV absorption spectroscopy, viscosity measurement, circular dichr...

The aim of this study is to evaluate the  effects of water deficit stress on chlorophyll fluorescence (CF) characteristics of photosystem II (PSII) and pigment contents in two rootstock seedlings (Pistacia atlantica L. and P. khinjuk L.). Three levels of soil water potential (Ψs) was used, including WWD (-0.05 MPa), MWD (-0.7 MPa) and SWD (-1.5 MPa). It was found that water stress increased the...

Background: Chromomycin A3 (CMA3) staining, with the slide method or fluorescence microscopy, is widely used for indirect assessment of protamine deficiency in a semen sample. Flow cytometry is the most suitable tool which to improve assessment accuracy, both in terms of statistical analysis and to prevent observer variation. This study provides a simple procedure to account for merocyanine 540...