From Extraction to Injection in a Single Process - A new Development for Automated Sample Preparation

SGE introduces a new tool for the on-line sample preparation: Micro Extraction by Packed Sorbent (MEPS) is a new development in the field of sample preparation by SPE (solid phase extraction). MEPS performs the same function as SPE, namely the purification or speciation of samples, but has some significant differences:

• MEPS saves labour time
• MEPS allows SPE methodology to be applied to small sample volumes (down to 10 μl)
• MEPS can be integrated into autosampler robotics and allows on-line use of SPE.
• MEPS can reduce sample and reagent consumption and waste disposal.
• MEPS is field portable for remote sampling with or without the use of automated equipment.
  

Construction
MEPS consists of two parts, the MEPS syringe and the Barrel Insert and Needle Assembly (BIN). This BIN contains the SPE phase, and is built into the syringe needle.

The barrel is used with a 100 μl or 250 μl gas tight MEPS syringe, that allows fluid handling at normal SPE pressure.


Minimum Sample volume and high Sensitivity
Sample volumes can be as little as 10 μl or alternatively larger sample volumes can be concentrated by taking multiple aliquots of 100 μl to 250 μl.

Automation
The advantage of MEPS lies in the ability to prepare and inject samples online using a single device. This reduces sample processing times and any intervention by the operator. The typical lifetime is about 40 – 100 samples, depending on the sample matrix. The small quantity of phase in the BIN can be easily washed between samples and thus avoids carry-over of sample.

MEPS is available in a variety of common SPE phases ( reversed phase, normal phase und ion-exchange phase).
The dimensions of the sorbent bed ensure that the sorbent performance remains identical to conventional SPE devices and therefore an easy down-scaling can be performed.

Automation of MEPS is easily adopted to the free programmable auto-injectors of CTC Analytics and Thermo Fisher Scientific without any modifications.

MEPS is a result of a collaboration between SGE, Mohamed Abdel-Rehim (Astra Zeneca) and Lars G. Blomberg (University of Karlstad).

The use of MEPS is illustrated in the video sequence.