Spectroscopic characterization of PEG-DNA biocomplexes by FTIR

Understanding the mode involved in the binding of certain molecules to DNA is of prime importance, and PEG offers wide-ranging applications in biological, medical and pharmaceutical contexts. FTIR spectroscopy has been used to characterize how the formed biocomplexes bind or dissociate to/from each other between PEG400-ctDNA under different conditions. Characterization and investigation of the effect of incubation time on PEG400-ctDNA biocomplexes formation were studied through spectroscopic technique FTIR. The influence of time duration and incubation on intermolecular interaction was analysed at three different selected times (Zero, 1hr, and 48 hrs.) at 1:1 PEG400-ctDNA monomer to nucleotide ratio. The experiment was carried out at room temperature 22 °C, with prior vortex stirrer of biocomplex for 10 min to improve homogeneity of sample. The results showed that the binding reaction of PEG400-ctDNA proceeds rapidly through DNA base pairs and phosphate DNA backbone, and complexation was reached after a maximum 1hr after mixing PEG400 and ctDNA at 1:1 ratio. FTIR spectroscopy results suggest that PEG400 binds with ctDNA by weak to moderate biocomplexes formation, with both hydrophilic and hydrophobic contact through DNA base pairs, with minor binding preference towards phosphate backbone of DNA helix. The mode of interaction most likely referred to an interaction through outside groove binding or electrostatic binding modes. FTIR highlighted the significant effect of incubation time on the stable biocomplexes of non-ionic PEG400 and ctDNA. Moreover, FTIR spectroscopy technique was rapid, showed good stability, and is a valuable tool for studying the biological properties of biocomplexes of PEG400 and ctDNA

The relation between sunscreen and skin pathochanges mini review

Nowadays, cosmetic products represent the most important non food market sector for producers. Consumers are in continues demand to products for beauty, antiageing, wellness, skin care and sunscreen. Sunscreen help to protect skin from UV rays, either chemically or physically. UV rays are generally consists of three forms UVA, UVB and UVC, and excessive exposure of these radiation may lead to pigment changes, pre-cancerous, cancerous skin, wrinkles and skin aging , along with triggering other adverse light sensitive reactions based on disease etiology and skin prototypes.The possible pathological changes due to use of sunscreen has been reviewed during the exposure to the UV rays. It is vital to protect skin and eyes from damaging effects as the skin is an integral part of our immune system. Moreover, artificial sources of UV rays should be avoided including tanning beds and sunlamps unless use of sunscreen. Surfaces such as sand, snow, concrete and water can reflect up to 85% of UV radiation, when around these surfaces, even when cloud weather because it filters less than 40 % of UV radiation. The used sunscreen products should contain SPF of at least 15 and it is advisable to have enough vitamin D and beta carotene and antioxidants such as vitamin C, vitamin E and Selenium when heavily exposed to sun radiation