Prepare 2 mg/mL Aquaphile™ coelenterazine stock solution. For component 10126-200ug, add 100 uL water to the vial and mix. For component 10126-4mg, add 2 mL water to the vial and mix. Stock solutions of Aquaphile coelenterazine can be stored for up to 3 months at -20oC or below.