Before revision: the protein and mPEG-aldehyde are dissolved using sodium phosphate buffer with sodium cyanoborohydride, which acts as a reducing agent that conditions the aldehyde group of mPEG-aldehyde to have a strong affinity toward lysine residue of N-terminal of lysozyme.
After revision: The protein and mPEG-aldehyde are dissolved using sodium phosphate buffer with sodium cyanoborohydride, which acts as a reducing agent and conditions the aldehyde group of mPEG-aldehyde to have a strong affinity towards the lysine residue on thea N-terminal of lysozyme.