Potassium iodide

Methoxy poly(ethylene glycol) with  a number average molecular weight of 550 (MPEG550), ethanolamine, sodium hydride, silver sulfate, sodium diethyldithiocarbamate, phosphonitrilic chloride trimer and aluminium chloride were procured from Sigma-Aldrich. Anhydrous tetrahydrofuran was procured from Merck. Potassium tetrachloroplatinate(II) (Kojima Chemicals), potassium iodide (Junsei Chemicals) and ammonium hydroxide (Daejung Chemicals) were used as received. phosphonitrilic chloride trimer was purified by sublimation. cis-Diamminediaquoplatinum(II) sulfate was prepared from cis-diamminediiodoplatinum(II) as reported previously.17 (link) Poly(dichlorophosphazene) was prepared by thermal polymerization of phosphonitrilic chloride trimer in the presence of AlCl₃ catalyst as detailed in our earlier publication.18 (link) Human alveolar basal epithelial carcinoma cell line (A549) and human gastric cancer cell line (MKN-28) were purchased from Korean Cell Line Bank (Seoul, Korea). BALB/c nude mice (male, 5 weeks, 20 ± 2 g) and ICR mice (male, 5 weeks, 20 ± 2 g) were purchased from Orient Bio Inc. (Gyeonggi-do, Korea)

To measure the peroxide value of each sample, lipid extraction was performed according to ISO Standard 14156: 2001 (International Organization for Standardization, 2001 ). One gram of extracted lipid was melted in 25 mL of acetic acid (Daejung Chemicals & Metals Co., Ltd.) and chloroform (Daejung Chemicals & Metals Co., Ltd.) (3:2). Then, the samples were left in a dark room after being mixed slightly with 1 mL of a saturated solution of potassium iodide (Junsei Chemical Co., Ltd, Japan). After admixing strongly with 30 mL of water, 0.01 N sodium thiosulfate (Daejung Chemicals & Metals Co., Ltd.) was titrated using 1 mL of a starch solution (Yakuri Pure Chemicals Co., Ltd, Kyoto, Japan) as an indicator.
$\text{Peroxide value }\left(\text{meq/kg}\right)\text{ = }\frac{a–b\times f}{\text{amount of sample}\left(\text{g}\right)\times 10}$
Where a is the amount of 0.01 N sodium thiosulfate (mL) used in the sample test, b is the amount of 0.01 N sodium thiosulfate used in the blank test, and f is the titer of 0.01 N sodium thiosulfate.

Hydrogen peroxide (H₂O₂) and sodium hydroxide (NaOH) were acquired from Samchun Pure Chemical Co., Ltd. (Korea). Potassium biphthalate (C₈H₅KO₄) was obtained from Daejung Chemical &Metals Co., Ltd. (Korea). Potassium iodide (KI) and ammonium molybdate ((NH₄)₂MoO₄) were purchased from Junsei Chemical Co., Ltd. (Japan). Luminol (3-aminophthalhydrazide, C₈H₇N₃O₂) was acquired from Sigma–Aldrich Co. (USA). All chemicals were used as received.