Divide the total peptide amount by the reconstitution volume: 10mg ÷ 2mL = 5mg/mL concentration. If your target dose is 250mcg (0.25mg), divide by concentration: 0.25mg ÷ 5mg/mL = 0.05mL (50 units on an insulin syringe).
USP Chapter 795 provides pharmaceutical calculation standards for reconstituted medications.