Hemoperfusion using metal ion affinity adsorbent is a promising method to remove human testosterone in plasma. Due to the leakage of metal ion from the adsorbents, there is no metal ion affinity adsorbent for hemoperfusion. In this study, chitosan was used to coat the adsorbent for preventing the leakage of Zn loaded. Meanwhile, freeze-drying method was used to enhance adsorption capacity of Zn-loaded cellulose beads for testosterone. The results indicate that after the adsorbent was coated by 0.02% chitosan solution, the highest adsorption percentage reached 48%, during adsorption, the Zn concentration in plasma did not increase; the adsorption capacity of the adsorbent can be significantly enhanced by freeze-drying. The results may be caused by porosity of the adsorbent enlarged via freeze-drying and improved stability by coating with chitosan. In addition, the adsorbent shows better selectivity and storage stability and could be a potential adsorbent to treat prostate cancer.

Immobilized metal ion affinity adsorbents have been widely used in separation technique15 to purify proteins. Due to the leakage of metal ion from the adsorbents, there is no metal ion affinity 16 adsorbent for hemoperfusion has been applied to clinical trial. In this study, in order to prevent the 17 leakage of Zn 2+ loaded from cellulose beads based adsorbent, improve its stability and adsorption 18 capacity for testosterone, Freeze-drying method was used to enhance the porosity of cellulose 19 beads, improve the surface area of the cellulose beads and adsorption capacity for testosterone. 20Chitosan was used to coat the adsorbents for preventing the leakage of Zn 2+ loaded and improve 21 the adsorbent's stability. Moreover, the factors affecting adsorption ability and some components