3. Reagents
a. Phenol solution: Mix 1.11 mL liquified phenol (89%) with 95% v/v ethyl alcohol to a final volume of 100 mL. Prepare weekly. CAUTION: Wear gloves and eye protection when handling phenol; use good ventilation to minimize all personnel exposure to this toxic volatile substance.
b. Sodium nitroprusside, 0.5% w/v: Dissolve 0.5 g sodium nitroprusside in 100 mL deionized water. Store in amber bottle for up to 1 month.