Solid-phase microextraction based method for determination of essential oils components in herbal beverages.

A method employing the direct immersion solid-phase microextraction followed by GC-MS analysis is presented for the determination of essential oils components in herbal tea infusions, i.e. their direct content in the liquid phase.

Microextraction by packed sorbent (MEPS) as a suitable selective method for l-ascorbic acid determination in beverages.

In this study the modern microextraction by packed sorbent (MEPS) method followed by HPLC-UV analysis was optimised and evaluated for determination of l-ascorbic acid (AA) content in beverages. In this case 300μL of sample was passed through silica BIN (barrel insert and needle assembly) and entrapped AA was eluted by 60μL of methanol-water (10%, v/v) solution. Recovery of the proposed method for three concentration levels ranged between 97.