1. Protein Research Center, Shahid Behshti University, Tehran, Iran 2. Protein Research Center, Shahid Behshti University, Tehran, Iran
Graphene oxide (go) has been used as a matrix for lipase immobilization. go chemical properties are reported beneficial also for enzymatic activity modifications. the enzyme adsorption capacity of go is also high and hence suitable for catalysis.
Single layer graphene oxide thermomyces lanuginosus lipase (tll) was physically immobilized on single layer graphene oxide(go). effect of buffer ph and incubation temperature investigated. the effect of different concentrations of nacl was investigated during adsorption and after immobilization.
According to the result of zeta potential and salt effect tests ph and incubation temperature have important role in orientation of lipase attachment that finally causes different behaviour of absorbed lipase. for exploring this issue lipase was absorbed on the go in two different condition. the one in buffer ph 7 , incubation temperature 20 ℃ and buffer concentration 250 mm and the seccond is 9, 40 ℃ and 500 mm sequenselly for ph , temperature and buffer concentration.
Activity assay determined that ph and temperature have the most important role in adsorbed lipase activity. hence, it is showed that each condition induce different charge to the lipase and consequently different orientation of lipase in relation to the go surface.