@article{assis_2003,  title={Scanning electron microscopy study of protein immobilized on SIO2 Sol-gel surfaces},  volume={20},  ISSN={0104-6632},  url={https://doi.org/10.1590/S0104-66322003000300014},  DOI={10.1590/S0104-66322003000300014},  number={3},  journal={Brazilian Journal of Chemical Engineering},  publisher={Brazilian Society of Chemical Engineering},  author={Assis, O.B.G.},  year={2003},  month={Jul},  pages={339–342} }