Nickolaj Petersen
Lektor
E-mail: njp@farma.ku.dk
Telefon: 35 33 61 84
Rum: 13/622

Developing new techniques for sample focusing and concentration
Miniaturized systems offer several advantages compared to conventional analytical equipment such as fast analysis and a possibility of full integration of all steps for a chemical analysis. The small channel dimensions allow fast reaction kinetics and ultra fast separations with minimum consumption of reagents and solvents. The downside of small channel dimensions is a limitation to the sensitivity as only tiny amounts of sample are injected. Typically, the analyzed sample volumes are less than 0.01 μL, and even injecting less than 0.1 pL (110-7 μL) is not unusual. In this project you will work on developing new ways of focusing and concentration the sample before and during the separation. The techniques are based on new effects that have been discovered for electrokinetic transport. These principles may be used for both miniaturized and large-scale sample pretreatment.
Supervisor: Nickolaj J. Petersen.
Number of students: 1.

On-line sample preparation coupled to electrospray ionization – mass spectrometry
We have recently demonstrated a new way of performing continuous liquid-liquid extraction on microfluidic devices. Target analytes from biological sample can be selectively extracted from a flowing sample solution, through a 25 µm thick supported liquid membrane (SLM) and into a flowing acceptor solution. The extraction across the organic SLM is controlled by an applied electric potential across the membrane (electro membrane extraction). The flowing acceptor solution can be coupled online to a mass spectrometer for continuous monitoring. In this project you will use the devices for studying the metabolism of drugs in real time. The online coupling of metabolism with MS is particularly interesting because it may reveal short-lived reactive metabolites as well as the kinetics of the metabolism.
Supervisor: Nickolaj J. Petersen.
Number of students: 1.