Labs & TestbedBio & Chemical Lab

Bio & Chemical Lab

To develop new immunoassay platforms, we work with a variety of materials (metals, polymers Si-based substrates, etc.) that form substrates (thin films, nanoparticles) where chemical reactions take place. Effective system development and evaluation requires a well-equipped laboratory.

Optical characterization of materials and of chemical reactions
We use a two-beam spectrophotometer (Perkin Elmer) to quantify the absorbance of various suspensions, for example, to characterize suspensions of gold nanoparticles. 

Spectrophotometer Fluoromax-P, Horiba/Jobin Yvon to determine optical spectra of solutions and solid samples from mid-UV to near-IR. It is equipped with two polarizers for incident and reflected/fluorescent light. Thus, we are able to study the effect of polarization on fluorescence excitation as well as on the emission of fluorescent light. It is also equipped with an option for time-resolved studies with time resolution down to a few nsec.

Fluorometer (Fluroskan Ascent FL, ThermoLabsystems) accepts commonly used microtiter plates, microscope slides, etc. for absorbance and fluorescence measurements. It enables us to measure fluorescence variations across a well with lateral resolution better than 2 mm2.

Ellipsometer (Multiskop, Optrel) can be used to monitor thickness changes of thin films. The instrument is also equipped with a contact-angle measurement facility and with surface-plasmon-resonance option.

Real-time monitoring of chemical reactions laboratory has a quartz crystal microbalance with dissipation monitoring (QCM-D 3D, Q-Sense) for real-time monitoring of surface reactions by gravimetry. We can also use the surface plasmon resonance option available in Multiskop to monitor the kinetics of surface reactions optically.

Both the QCM-D and the SPR enable us to monitor each step of a chemical reaction in real time. They work without any labels, such as fluiorescent tags. This is of particular importance when optimizing the chemistry of multistep assays such as sandwich ELISA’s. For example, standard techniques for measuring fluorescence give only an evaluation of the performance of the assay as a whole, while surface techniques allow us to monitor the binding of the capturing antibody, blocking molecules, and antigens and to detect antibodies separately (sequentially). In addition, these techniques do not require specific preparation of read-out chemistries as is necessary when using fluorescence or absorbance-based detection.

Dynamic light-scattering. Our laboratory has a photon-correlation spectroscope (Nanosizer Z, Malvern UK) for the measurement of particle-size distributions. Thus, we can follow changes in particle sizes, such asthe kinetics of aggregation as a function of the change in particle surface coating and suspension chemistry (pH, salt concentration, etc.). This equipment also allows us to measure the isoelectric point – the z-potential – of molecule/particle suspensions. and ζ-potential measurements indicate the stability of suspensions and also enable us to monitor changes in the particle charge as a function of the changed chemistry of the nanoparticles.

People

Sara Bogren
Senior Scientist
+46 70 915 18 08
sara.bogren [at] ri.se

Kristina Fogel
Senior Scientist/Project Manager
+46 (0)70 915 27 10
kristina.fogel [at] ri.se

Anatol Krozer
Senior Expert
+46 (0)70 915 18 06
anatol.krozer [at] ri.se

Cristina Rusu
Senior Expert, Micro System technology
+46 (0)70 915 18 26
cristina.rusu [at] ri.se

Publications
Projects

Completed projects