Immediately before use, STZ was dissolved in 10 mM sodium citrate buffer, pH 4-4.5, made isotonic by the addition of an appropriate volume of 0.25 M NaCl
Immediately before use, STZ was dissolved in 10 mMsodium citrate buffer, pH 4-4.5, made isotonic by the additionof an appropriate volume of 0.25 M NaCl