A new method for cellulose membrane fabrication and the determination of its characteristics.

A novel method to fabricate semipermeable cellulose membranes based on cellulose regeneration of a dry membrane cast by the neutralization reaction is presented in this paper. In this method, an environmentally acceptable cellulose dissolution procedure is employed to prepare the membrane casting solution comprised of microcrystalline cellulose dissolved in aqueous NaOH. Moreover, a new cast drying/cellulose regeneration technique is proposed and successfully applied to prepare membranes after the exploitation of the conventional immersion precipitation method, which results in the formation of granular cellulose particles rather than membranes due to the low cellulose concentration (<5 wt%) in the cast.

A New Co Complex as a Bulge-Specific Probe for DNA.

Bulge cleavage of two or three bases occurs when a DNA substrate is specifically cleaved oxidatively by [Co (tfa) (happ)] (see picture). Hydrogen peroxide is necessary for the activation of this octahedral complex, which suggests that hydroxyl radicals are the reactive species. The complex has no significant reactivity towards the corresponding sequence in a single-stranded DNA region, and it exhibits only a low affinity towards double-stranded DNA.