Four variables "extraction time; extraction temperature; ratio of liquid to solid and extraction number" were regarded as factors in the optimization study.
The four factors were NaOH concentration (A), extraction temperature (B), ratio of NaOH to solid (C), and extraction time (D).
where Y represents the yield of RBP, X 1, X 2 and X 3 represent ratio of water to solid, extraction temperature and extraction time, respectively.
The isoprostanes were extracted and purified with solid phase extraction and thin layer liquid chromatography and then converted to trimethylsilyl ether derivatives and analyzed by GC-MS.
To this end, an analytical method based on a solid liquid extraction followed by cleaning up with gel permeation chromatography (GPC) and solid phase extraction (SPE) and GC-IDMS determination, was validated in-house.
Samples were added to C8 solid-phase extraction tubes and extracts were dried on an evaporator.
A. Capozzi and T.C. optimized the solid sample extraction and ex situ dissolution procedure and performed the in vitro13C hyperpolarized MRS measurements.
Extraction yield was related with four variables, including ratio of solution to solid, extraction power, buffer time, and extraction time.
Under the optimal extraction condition (extraction time 180 min, ratio of water to solid 6, extraction temperature 100 °C, and extraction number 4), extraction yield of ASP was 5.6%.
They underwent sample clean-up and extraction by solid phase extraction techniques.
