Lignosulfonate (LS)/mercerized cotton composite was prepared to study the LS suppressive possibility to control malignant cell activities to facilitate chemotherapy treatment. The composite was characterized by cross-polarized/magic angle spinning 13 C nuclear magnetic resonance (NMR) spectrometry and scanning electron microscope (SEM). 13 C NMR spectra and SEM indicated that the presence of LS increased crystallinity and porosity of mercerized cellulose, respectively. Furthermore, the composite efficacy against cancer cell activity was evaluated by cytotoxicity for malignant cell line HCT116, HepG2, and MCF-7. The cancer cells thrive in an acidic environment and they do not survive in normal or alkaline media. The release of LS was intended at acidic pH, in which, the acidity increased due to the activity of the cancer cells that activate the LS released from the mercerized cotton into the media. Therefore, this release process reduced the activity of cancer cells. The released LS kept cancer cells in a low activity via decreasing acidity. Hence, the composite may not eliminate the cancer cells, but it reduces the activity of cancer cells.