| Abstract: | Reportedly, determination of several phospholipids in amniotic fluid, including phosphatidylglycerol and phosphatidylinositol, in addition to lecithin and sphingomyelin improves prediction of neonatal pulmonary function. In this study, we evaluated a two-dimensional technique for separating and measuring these phospholipids and compared it with a simpler one-dimensional procedure. The two-dimensional technique was adapted to readily available commercial plates, and a preheating step was introduced to avoid shattering of the plates during charring. The Rf values, reproducibility of each technique, and the correlation between them were examined. Even though the one-dimensional technique is faster and less expensive, we recommend the two-dimensional method for clinical use because of better precision (CV for phosphatidylglycerol 15% vs 21%) and clearer results when relatively little phosphatidylglycerol is present. The one-dimensional procedure is unreliable when blood or meconium are present. In addition, interfering compounds co-migrate with phosphatidylglycerol, phosphatidylethanolamine, and phosphatidylserine in the one-dimensional technique. Before any one-dimensional lipid separation is adopted for clinical use, it should be critically compared to the two-dimensional procedure. |
