Nonaqueous Oxidation in DNA Microarray Synthesis Improves the Oligonucleotide Quality and Preserves Surface Integrity on Gold and Indium Tin Oxide Substrates.

Nucleic acids attached to electrically conductive surfaces are very frequently used platforms for sensing and analyte detection as well as for imaging. Synthesizing DNA on these uncommon substrates and preserving the conductive layer is challenging as this coating tends to be damaged by the repeated use of iodine and water, which is the standard oxidizing medium following phosphoramidite coupling. Here, we thoroughly investigate the use of camphorsulfonyl oxaziridine (CSO), a nonaqueous alternative to I2/H2O, for the synthesis of DNA microarrays in situ. We find that CSO performs equally well in producing high hybridization signals on glass microscope slides, and CSO also protects the conductive layer on gold and indium tin oxide (ITO)-coated slides. DNA synthesis on conductive substrates with CSO oxidation yields microarrays of quality approaching that of conventional glass with intact physicochemical properties.

Current aspects in treatment of breast cancer based of nanodrug delivery systems and future prospects.

Breast cancer is one of the most common diseases worldwide. The risk of getting this disease in female is 30% and the mortality rate is 14%. The breast cancer treatment is based on surgery, chemotherapy and radiotherapy. However, an effective treatment method has not been developed. The main cause of failure in the treatment is cancer stem cells metastasis and chemo-resistance. The use of nanocarrier systems against breast cancer stem cells has great importance. Not only advantages of polymeric drug delivery systems are increasing the stability and reduce the side effects of drugs, but also they have disadvantages such as biocompatibility and long-term potential safety. However, in recent years, studies on exosomes provide several advantages. Exosomes usage as nanocarrier do not cause immunological reactions also the drug effectively transport into the cytosol of targeted cell and have more stability characteristics. Although there are studies about various nanocarrier systems in literature against breast cancer but in general, we have not found any review that brings them together and develops a systematic approach to solving the problem. This review mentions prospective new strategies based on various nanocarrier systems and emphasize the importance of exosome based on drug delivery systems in the treatment of breast cancer.