A reliable, rapid and accurate method based on spiked calibration curves and direct sample introduction was developed for determination of 17 pesticide residues in rice by gas chromatography-mass spectrometry single quadrupole selected ion monitoring GC/MS-SQ-SIM. Sample preparation is based on extraction with acetonitrile without clean up. The use of spiked calibration curves for constructing ...

Most current methods of circulating tumour cell (CTC) enrichment target the epithelial protein EpCAM, which is commonly expressed in adenocarcinoma cells. However, such methods will not recover the fraction of CTCs that have a non-epithelial phenotype due to epithelial-mesenchymal transition. For phenotype-independent CTC enrichment, we developed a new enhanced negative depletion strategy-terme...

Cucumber is one of the main vegetables in Iranian food basket. A wide range of pesticides are used for crops protection during the cultivation of vegetables such as cucumber due to heavy pest infestation. Analysis of pesticide residues in food and other environmental commodities have become essential requirement for consumers, producers, and food quality control authorities. This study was aime...

In this study, the effects, fate and transport of ENPs in wastewater treatment plants (WWTP) were investigated using three parallel pilot WWTPs operated under identical conditions. The WWTPs were spiked with (i) an ENP mixture consisting of silver oxide, titanium dioxide and zinc oxide, and (ii) bulk metal salts. The third plant served as control (unspiked). ENP effects were evaluated for (i) b...

Three simple and sensitive spectrophotometric methods are described for the determination of ofloxacin (OFX) in pharmaceuticals and in spiked human urine. First and second methods are based on the measurement of absorbance of OFX in 0.1 M HCl at 293 nm (method A) and 0.1 M NaOH at 287 nm, respectively. The third method is based on the measurement of 2:1 complex formed between OFX and iron(III) ...

The effect of a metal mixture (Cu, Zn, Pb, and Ni) on Cd fractionation in sediment and its accumulation by the freshwater macrophyte Eriocaùlon septangulàre was examined in an in situ experiment in the littoral zone at the Experimental Lakes Area, northwestern Ontario, Canada. Fresh sediment was spiked with Cd alone and together with the metal mixture at three concentration levels. Macrophytes ...

Solid phase extraction is one of the major applications of molecularly imprinted polymers fields for clean-up of environmental and biological samples namely molecularly imprinted solid-phase extraction. In this study, solid phase extraction using the imprinted polymer has been optimized with the experimental design approach for a triazine herbicide, named atrazine with regard to the critical fa...

The presence and quantity of rare cells in the bloodstream of cancer patients provide a potentially accessible source for the early detection of invasive cancer and for monitoring the treatment of advanced diseases. The separation of rare cells from peripheral blood, as a "virtual and real-time liquid biopsy", is expected to replace conventional tissue biopsies of metastatic tumors for therapy ...

Due to the difficulty in dispersing some engineered nanomaterials in exposure media, realizing homogeneous distributions of nanoparticles (NP) in soil may pose major challenges. The present study investigated the distribution of zinc oxide (ZnO) NP (30 nm) and non-nano ZnO (200 nm) in natural soil using two different spiking procedures, i.e. as dry powder and as suspension in soil extract. Both...

An isocratic analytical method based on liquid chromatographic determination with UV detection is described for the determination of isatin in spiked plasma and in its synthetic mixture. The separation of the isatin was achieved on a betasil C-8 column using a mobile phase consisting of a binary mixture of acetonitrile and buffer (Na2CO3 + NaHCO3). The linearity, accuracy and precision were fou...