To capture negatively charged nitrate ions in solution, cationic polyacrylamide (CPAM) as a viable, watersoluble, cost-effective, and non-toxic polymer can be employed . It is typically a microblock structure, where modifying the functional groups of each block helps to adjust its physicochemical properties . For instance integrating charged ammonium moieties with neutral polyacrylamide segments creates a di-block polymer that balances structural stability with electrostatic interactions . Strong electrostatic repulsion within the structure extends the molecular chain, enhancing ion accessibility to the charged segments and thereby increasing ion adsorption . Notably, the block ratio (i.e., the ratio between number of monomers in each block) directly impacts the polymer's performance where for instance a high charge density can induce repulsion and destabilization . Therefore, selecting the right block ratio is critical to achieve higher efficiency .