Search

Statistics show that breast cancer is the first cause of cancer-related deaths in women worldwide. Doxorubicin (DOX) is one of the chemotherapeutics with high efficacy in breast cancer. Nevertheless, due to its lack of specificity, it causes severe adverse effects and that is how the targeting delivery to cancer cells with high precision and efficiency becomes crucial. Combining nanoparticles and active targeting agents in forming a drug delivery system (DDS) for cytotoxic drugs is a promising strategy to circumvent the drawbacks of chemotherapy. Herein, a new dual-targeting delivery system for DOX was fabricated by loading DOX into mesoporous silica nanoparticles (MSN) which were then covalently attached to AS1411 aptamer and electrostatically conjugated to RGDK-octa-arginine peptide sequence (RGDK-R). The in vitrodata elucidated a significant safety effect of the encapsulated DOX in MSN.COOH decorated with AS1411 and RGDK-R for non-cancerous cells, while the same toxicity as DOX towards breast cancer cells. In vivoresults indicated that the designed system could effectively improve the inhibitory effect of DOX on tumor growth with single-dose administration.

A new design of equilibrium hollow fiber solid-liquid phase micro-extraction (HF-SLPME) was developed for the determination of Zn(II) in environmental water samples. Membrane extraction with sorbent interface which we used in this research is a two-phase supported liquid membrane consisting of aqueous (donor phase), organic solvent/nano sorbent membrane (acceptor phase) system operated in direct immersion sampling modes. Where the multiwalled carbon nanotube dispersed in the organic solvent is held in the pores of a porous membrane supported by capillary forces and sonification. All microextraction experiments were supported using an Accurel Q3/2 polypropylene hollow fiber membrane (600 ?m I.D., 200 ?m wall thicknesses, 0.2?m pore size). The experimental setup is very simple and highly affordable. Among most of micro-extraction techniques reported, it is the most effective sample preparation/preconcentration technique. The hollow fiber is disposable, so single use of the fiber reduces risk of crosscontamination and carry-over problems. The proposed method allows the very effective and enriched recuperation of ionic analyte into MWCNTs/organic phase. In order to obtain high enrichment and extraction efficiency of the analyte using this novel technique, the main parameters were optimized. Under the optimized extraction conditions, the method showed good linearity, repeatability, low limits of detection and very excellent enrichment factor (EF = 950).