Nonlinear dynamic phase contrast microscopy for microfluidic and molecular biology applications


Speaker: Professor Cornelia Denz (Institut für Angewandte Physik and Center for Nonlinear Sciences,Westfaelische Wilhelms-Universität Münster, Germany)
Date: 11th September 2009

In live sciences, the observation and analysis of moving living cells, molecular motors or motion of micro- and nano-objects is an actual field of research. Especially in the field of system biology and nano-medicine, a complete in vivo analysis of the molecular dynamics of functional systems is one of the challenges of the near future. At the same time, micro fluidic innovations are needed for biological and medical applications on a micro- and nano-scale. Conventional microscopy techniques are reaching considerable, principle limits with respect to these issues.

A promising approach for this challenge is nonlinear dynamic phase contrast microscopy. It is an alternative full field approach based on nonlinear refractive index changes that allows to detect motion as well as phase changes of living unstained micro-objects in real-time, thereby being marker free, without contact and non destructive, i.e. biocompatible. The generality of this system allows it to be combined with several other microscope techniques as well as with optical tweezers or optical manipulation. In this talk I will present the nonlinear optics basics of the dynamic phase contrast technique and its applications in analysis of microorganismic dynamics, micro-flow velocimetry and micro-mixing analysis. Moreover, combinative approaches of nonlinear refractive index changes techniques with optical multifocus-tweezers are presented.