Solid phase extraction with electrospun nanofibers for determination of retinol and α-tocopherol in plasma

A novel packed-fiber solid phase extraction procedure based on electrospun nanofibers for simultaneous determination of vitamins A (retinol) and E (alpha-tocopherol) in human plasma has been developed. Parameters affecting extraction efficiency were investigated in detail. The limit of detection is 0.01 mu g mL(-1) for retinol, and 0.3 mu g mL(-1) for alpha-tocopherol. The linear range is from 0.05 to 2.0 mu g mL(-1) for retinol, and from 0.5 to 30 mu g mL(-1) for alpha-tocopherol. The precision (RSD) is < 6%, and the relative recovery > 90%. The method was applied to analysis of retinol and alpha-tocopherol in human plasma with satisfactory results.