Preparing some polyphenols in nano-dimension and determination of their antioxidative capacity

In recent years it has been reported that free radicals and oxidative stress play important roles in basic causes of some diseases. Thus, the importance of antioxidant compounds is increasing as free radical scavanging agents. This study aims to increase the antioxidant characteristics of polyphenol compounds by preparing them in nano-dimensions.In this study catechol, caffeic acid, p-coumaric acid, dopamin ve 4-metil catechol were prepared by using nano precipitation techniques. Antioxidant activities were compared by using DPPH, ß-karoten bleaching, reducing power, ABTS ve OH-. reducing power with in vitro antioxidan activity measuring techniques.Molecule size of catechol was reduced from 657 nm to 23.6 nm and in ABTS antioxidant activity test it showed % 12.94, in DPPH antioxidant activity test it showed % 13.65 more activity in nano-dimension than in basic-dimension. Molecule size of caffeic acid was brought to nano-dimension by decreasing it from 727 nm to 19.4 nm and in ß-karoten antioxidan activity measurement test, caffeic acid showed % 7.78 more activity in nano-dimension than in basic-dimension. Molecule size of p-coumaric acid was brought to nano-dimension by decreasing from 556 nm to 24.8 nm. In OH-. reducing power antioxidan activity measurement test, p-coumaric acid showed % 9.23 more activity in nano-dimension than in basic-dimension. Molecule size of dopamin was brought to nano-dimension by decreasing from 657 nm to 23.6 nm. In DPPH antioxidan activity measurement test, dopamin showed % 5.23 more activity in nano-dimension than in basic-dimension. It is seen that catechol, caffeic acid, p-coumaric acid, dopamin showed more antioxidan activity in nano-dimension than in basic-dimension, while 4-metil catechol showed the similar activity in both dimensions.It is stated that some polyphenols known for their antioxidant caharacteristics can be prepared in nano-dimension without losing their antioxidant characteristics by using nano-precipitation techniques.