Analysis of Alprostadil by HPLC with Post-Column Derivatization
Alprostadil (Prostaglandin E1) is a drug that has vasodilation properties and is used to treat erectile dysfunction and other medical conditions.
Alprostadil (Prostaglandin E1) is a drug that has vasodilation properties and is used to treat erectile dysfunction and other medical conditions. This medication is available in injectable form and in suppository form. Since Prostaglandin E1 has low UV absorbance, the analysis of the formulations could be difficult. The addition of post-column derivatization increases the sensitivity and specificity of the analysis.
Analytical Conditions
Analytical column: Reversed-phase C18 column (150 × 4.6 mm)
Temperature: 37 °C
Flow rate: 1 mL/min
Mobile phase: 30% Acetonitrile – 70% of 0.02 M Potassium Phosphate monobasic (adjusted to pH 3)
Or Alternative Conditions
Mobile phase: 25% Acetonitrile – 75% of 0.0067 M Potassium Phosphate buffer pH 6.3
Injection volume: 20 µL
Figure 1: Calibration curve for Alprostadil.
Post-Column Conditions
Post-column system: Pinnacle PCX
Reactor volume: 2 mL
Reactor temperature: 60 °C
Reagent: 1 mol/L Potassium Hydroxide
Reagent flow rate: 1 mL/min
Detection: UV 278 nm
Figure 2: Calibration curve for β-Naphthol.
Calibration
Alprostadil: 0.1 µg/mL – 10 µg/mL
β-Naphthol (Internal Standard) 0.25 µg/mL – 10 µg/mL
Figure 3: Chromatogram of Alprostadil and β-Naphthol (internal standard).
Make stock solutions of Alprostadil and β-Naphthol in anhydrous Ethanol. Prepare working standards by appropriate dilution of stock solution with mobile phase.
Pickering Laboratories, Inc.
1280 Space Park Way, Mountain View, CA 94043
tel. (800) 654-3330, (650) 694-6700
Website: www.pickeringlabs.com
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