Phosphonitrilic chloride trimer

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)

HAPS (POSS) in n-propanol (solids content 52.3
wt %) was kindly provided
by Funzionano AS. Phosphonitrilic chloride trimer (HCCP, 99%) and
dimethyl sulfoxide (DMSO, anhydrous, ≥99.9%) were obtained
from Sigma-Aldrich. Cyclohexane (EMSURE for analysis) and potassium
hydroxide (KOH, pellets extra pure) were obtained from Merck kGaA.
Ethanol (EtOH, 100% technical grade) was purchased from Boom. Porous
α-alumina discs (Ø 39 mm, thickness 2
mm) were obtained from Pervatech B.V. and used as the support.