Development and validation of a simple high-performance liquid chromatography analytical method for simultaneous determination of phytosterols, cholesterol and squalene in parenteral lipid emulsions.

A simple analytical method for simultaneous determination of phytosterols, cholesterol and squalene in lipid emulsions was developed owing to increased interest in their clinical effects. Method development was based on commonly used stationary (C18 , C8 and phenyl) and mobile phases (mixtures of acetonitrile, methanol and water) under isocratic conditions. Differences in stationary phases resulted in peak overlapping or coelution of different peaks. The best separation of all analyzed compounds was achieved on Zorbax Eclipse XDB C8 (150 × 4.6 mm, 5 µm; Agilent) and ACN-H2 O-MeOH, 80:19.5:0.5 (v/v/v). In order to achieve a shorter time of analysis, the method was further optimized and gradient separation was established. The optimized analytical method was validated and tested for routine use in lipid emulsion analyses.

Phytosterolemia in parenteral nutrition patients: implications for liver disease development.

OBJECTIVE: Phytosterols present in parenteral nutrition (PN) lipid emulsions have been linked to phytosterolemia and cholestatic liver disease, although no direct relation has been established. We investigated the relation among plasma phytosterol (PY) infused, total plasma PY levels, and possible links to PN-associated liver disease. METHODS: Twenty-seven adult patients on home PN were enrolled in the study. PYs were measured in plasma and lipid emulsions by gas chromatography. Liver function tests and blood counts were assessed to identify hepatic impairment, and biopsies were performed in eight patients. RESULTS: Mean total plasma PY level was higher in patients than in controls (55.4 +/- 6.2 versus 14.8 +/- 2.3 microg/mL). Simple linear regression models showed a correlation among total plasma PY, liver function tests, and platelet counts, which was stronger for total bilirubin (r(2) = 0.53, P = 0.0001) and aspartate aminotransferase (r(2) = 0.50, P = 0.0001) and weaker for platelet counts (r(2) = 0.158, P = 0.04); between infused lipid and liver function tests, the correlation was significant for total bilirubin (r(2) = 0.19, P = 0.038) and aspartate aminotransferase (r(2) = 0.164, P = 0.049). In multiple linear regression analysis, a decreased oral diet (b = -52.3, P = 0.001) and infused PY (b = 2.54, P = 0.093) were risk factors for high plasma PY levels (r(2) = 0.54). Biopsies showed moderate to severe liver impairment in five patients. CONCLUSION: Liver damage may be linked to high plasma PY levels and strengthened by lack of an oral diet in patients on home PN.