@article {46226, title = {Immobilization studies of Candida Antarctica lipase B on gallic acid resin-grafted magnetic iron oxide nanoparticles}, journal = {International Journal of nanomedicine}, volume = {14}, year = {2019}, month = {MAY}, pages = {3235-3244}, type = {Article}, abstract = {

Purpose: Here, we present the successful preparation of a highly efficient gallic acid resin grafted with magnetic nanoparticles (MNPs) and containing a branched brush polymeric shell.

Methods: Using a convenient co-precipitation method, we prepared Fe3O4 nanoparticles stabilized by citric acid. These nanoparticles underwent further silica modification and amino functionalization followed by gallic acid functionalization on their surface. Under alkaline conditions, we used a condensation reaction that combined formaldehyde and gallic, to graft the gallic acid-formaldehyde resin on the surface. We then evaluated the polymer-grafted MNPs to assay the Candida Antarctica B lipase(Cal-B) immobilization via physical adsorption.

Conclusion: Furthermore, during optimization of parameters that defined conditions of immobilization, we found that the optimum immobilization was achieved in 15 mins Also, optimal immobilization temperature and pH were 38 degrees C and 7.5, respectively. In addition, the reusability study of immobilized lipase polymer-grafted MNPs was done by isolating the MNPs from the reaction medium using magnetic separation, which showed that grafted MNPs reached 5 cycles with 91\% activity retention.

}, doi = {10.2147/IJN.S203547}, author = {SreeHarsha, Nagaraja and Ghorpade, Ravindra, V. and Alzahrani, Abdullah Mossa and Al-Dhubiab, Bandar E. and Venugopala, Katharigatta N.} } @article {46981, title = {Epoxy functionalized polymer grafted magnetic nanoparticles by facile surface initiated polymerization for immobilization studies of Candida Antarctica lipase B}, journal = {Reactive \& Functional Polymers}, volume = {147}, year = {2020}, month = {FEB}, pages = {104454}, type = {Article}, abstract = {

Immobilization of Candida Antarctica lipase B (Cal-B) was done on the epoxy functionalized polymer (EFP) grafted magnetic nanoparticles (MNPs) via covalent attachment with the active epoxy groups. The EFP brushes were grafted on iron-oxide based MNPs by a facile surface-initiated atom transfer radical polymerization (ATRP) using activators generated by electron transfer (AGET) of glycidyl methacrylate (GMA). Each step of the surface modification, polymer grafting, and enzyme immobilization process on the polymer grafted MNPs was studied using Fourier transform infrared spectroscopy (FTIR). A thermogravimetric analysis (TGA) calculated the amount of engineered organic components, a transmission electron microscopy (TEM) visualized the core-shell formation of the MNPs, and a vibrating sample magnetometer (VSM) validated their magnetic properties at various modification stages. The lipase immobilization efficiency was described as a function of immobilization time, as well as, enzyme amount. The activity was characterized within a range of pH, temperature, kinetic parameters, resusability and storage stability, for both the free and immoblized Cal-B enzyme. The results of this study suggested that poly(GMA) grafted MNPs can be successfully used for the immobilization of Cal-B with improved efficiencies compared to those obtained with free soluble lipase. The reported enzyme immobilization method appears to be reproducible and scalable for industrial production.

}, keywords = {Cal-B enzymes, enzymes, Immoblization, Magnetic nanoparticles}, issn = {1381-5148}, doi = {10.1016/j.reactfunctpolym.2019.104454}, author = {Afzal, Haq Asif and Ghorpade, Ravindra V. and Thorve, Asmita K. and Nagaraja, Sreeharsha and Al-Dhubiab, Bandar E. and Meravanige, Girish and Rasool, Sahibzada Tasleem and Roopashree, Teeka S.} }