A Comparable Study on the Effects of Pristine and Functionalized Single-Walled Carbon Nanotubes on Schwann Cells

A comparable study on the effects of pristine and functionalized single-walled carbon nanotubes on schwann cells were conducted. Schwann cells were co-cultured with three types of SWNTs, purified raw SWNTs (C), hydroxyl purified SWNTs (C-OH) and carboxyl purified SWNTs (C-COOH) at 25μg/mL. C-COOH promoted the cell viability after 72h exposure and sustained its redox states by enhancing GPx expression. On the contrary, C and C-OH weaken the antioxidant activity due to the inhibition in main antioxidant enzymes and further led to the decline in cell viability. Carboxyl modification of the SWNTs helps to improve the biocompatibility of the SWNTs by strengthening the antioxidant ability.

Influence of ssDNA Immobilization on the Conductance of Solution Gated Graphene Transistors

Carboxyl-modified graphene materials in both oxide and reduced state were explored in parallel for the preparation of field-effect transistors (FET). They were solution gated by phosphate buffer solution (PBS) (pH 7.2). Their conductance were examined and compared with unmodified graphene transistors, firstly. Then, after single strand DNA molecules were immobilized on reduced and oxide graphene transistors, their conductance and compared. Here ssDNA molecules were amino-tagged at the terminal five. It was found that ambipolar characteristic was exhibited by reduced graphene transistors, even they were undergone carboxyl modification. And it was also discovered that there were opposite conductance variation with the increasing of ssDNA concentrations and bigger changes were obtained by reduced carboxyl-modified graphene transistors.

Yeast enolase carboxyl modification using Woodward's reagent K

Yeast enolase is inactivated by Woodward's reagent K. Substantial protection is afforded by binding of 1 mol of "conformational" metal ion/subunit. Inactivation is correlated with modification of 13 carboxyl groups/subunit in the absence of conformational metal ion and 17 in its presence. Ten tryptic peptides labeled by Woodward's reagent K can be isolated, mostly from the C-terminal half of the protein. The changes in reactivity of these peptides produced by conformational metal ion suggest direct coordination to Glu-181 together with a contraction of the protein.