The C 1s spectrum can be deconvoluted into the following four components: C C (∼284 eV),C N (∼285 eV), C O (∼286 eV), and C O (∼287 eV). On the other hand, the O 1s spectrum consist of three peaks, arising from the C O (∼531 eV), the C O (∼532 eV) and the SiO2(∼533 eV) components. The relative area of C C and C N components increased after chemical modification with ethylenediamine, which can be suggested due to the presence of its amine molecule conjugated to the protein.