Agarose fibers with glycerol and graphene oxide and functional properties for potential application in biomaterials.

Agarose has numerous applications in biochemistry and medical textiles. This study aimed to produce agarose-graphene oxide-glycerol fibers and analyze their properties. The agarose gel was prepared by dissolving the polymer in 9:1 (v/v) dimethyl sulfoxide (DMSO): H2O, followed by spinning in an ethanol bath (1:1 (v/v) ethanol: H2O) at 20 °C. Fibers were obtained using 8 % (m/v) agarose, 2 % (m/v) glycerol, and 0.5 % and 1 % (m/v) graphene oxide (GO). The fibers had a titer of 18.32-32.49 tex and, a tenacity of 1.40-3.35 cN/tex. GO increased the thermal resistance by 79 %. The presence of glycerol and GO was confirmed and analyzed by FTIR and XPS. Fiber water absorption was decreased by 30 % with the GO addition. The weight loss increased by 55 % after glycerol addition, 51 % with GO addition, and 36 % with glycerol and GO simultaneous addition. Furthermore, GO exhibited 100 % inhibition for both S. aureus (gram-positive) and E. coli bacteria (gram-negative). Fiber F1, with only agarose, inhibited S. aureus by 34.93 %, F2 with 2 % glycerol by 48.72 %, F3 with 0.5 % GO by 63.42 %, and F4 with 2 % glycerol and 0.5 % GO by 30.65 %. However, the inhibition increased to 49.43 % with 1 % GO. The agarose fibers showed low inhibition for E. coli, ranging from 3.35 to 12.12 %.

Efficacy of Punica granatum L. hydroalcoholic extract on properties of dyed hair exposed to UVA radiation.

The solar radiation promotes color fading of natural and dyed hair by free radical generation, which oxidize the pigments, and it has been proposed the incorporation of antioxidants in order to reduce the alterations of hair color. Due to its high content of polyphenols and tannins, which are potent antioxidants, the hydroalcoholic extract of Punica granatum L. (pomegranate) was used in this research. Hair care formulations containing pomegranate extract were applied to red dyed hair tresses, and these were exposed to UVA radiation. Non-ionic silicone emulsion presenting color protection properties were also used for comparison purpose between the results obtained with different treatments, including silicone in combination with the pomegranate extract. The pomegranate extract at 5.0% and 10.0%w/w was effective in preventing the hair color fading in 37.6% and 60.8%, respectively, but the association of hydroalcoholic extract and non-ionic silicone emulsion is not encouraged. Mechanical properties were not affected by UVA radiation, since significant differences in breaking strength were not observed. Considering the conditions which the tresses have been exposed, it was concluded that the pomegranate extract at 10.0% w/w in hair care formulations are effective in reducing color fading of red dyed hair.