TY  - JOUR
A1  - Rabehi, Amine
A1  - Garlan, Benjamin
A1  - Achtsnicht, Stefan
A1  - Krause, Hans-Joachim
A1  - Offenhäusser, Andreas
A1  - Ngo, Kieu
A1  - Neveu, Sophie
A1  - Graff-Dubois, Stephanie
A1  - Kokabi, Hamid
T1  - Magnetic detection structure for Lab-on-Chip applications based on the frequency mixing technique
JF  - Sensors
N2  - A magnetic frequency mixing technique with a set of miniaturized planar coils was investigated for use with a completely integrated Lab-on-Chip (LoC) pathogen sensing system. The system allows the detection and quantification of superparamagnetic beads. Additionally, in terms of magnetic nanoparticle characterization ability, the system can be used for immunoassays using the beads as markers. Analytical calculations and simulations for both excitation and pick-up coils are presented; the goal was to investigate the miniaturization of simple and cost-effective planar spiral coils. Following these calculations, a Printed Circuit Board (PCB) prototype was designed, manufactured, and tested for limit of detection, linear response, and validation of theoretical concepts. Using the magnetic frequency mixing technique, a limit of detection of 15 µg/mL of 20 nm core-sized nanoparticles was achieved without any shielding.
KW  - Lab-on-Chip
KW  - magnetic sensing
KW  - frequency mixing
KW  - superparamagnetic nanoparticles
KW  - magnetic beads
Y1  - 2018
U6  - http://dx.doi.org/10.3390/s18061747
SN  - 1424-8220
VL  - 18
IS  - 6
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Albanna, Walid
A1  - Kotliar, Konstantin
A1  - Lüke, Jan Niklas
A1  - Alpdogan, Serdar
A1  - Conzen, Catharina
A1  - Lindauer, Ute
A1  - Clusmann, Hans
A1  - Hescheler, Jürgen
A1  - Vilser, Walthard
A1  - Schneider, Toni
A1  - Schubert, Gerrit Alexander
T1  - Non-invasive evaluation of neurovascular coupling in the murine retina by dynamic retinal vessel analysis
JF  - Plos one
N2  - Background
Impairment of neurovascular coupling (NVC) was recently reported in the context of subarachnoid hemorrhage and may correlate with disease severity and outcome. However, previous techniques to evaluate NVC required invasive procedures. Retinal vessels may represent an alternative option for non-invasive assessment of NVC.

Methods
A prototype of an adapted retinal vessel analyzer was used to assess retinal vessel diameter in mice. Dynamic vessel analysis (DVA) included an application of monochromatic flicker light impulses in predefined frequencies for evaluating NVC. All retinae were harvested after DVA and electroretinograms were performed.

Results
A total of 104 retinal scans were conducted in 21 male mice (90 scans). Quantitative arterial recordings were feasible only in a minority of animals, showing an emphasized reaction to flicker light impulses (8 mice; 14 scans). A characteristic venous response to flicker light, however, could observed in the majority of animals. Repeated measurements resulted in a significant decrease of baseline venous diameter (7 mice; 7 scans, p < 0.05). Ex-vivo electroretinograms, performed after in-vivo DVA, demonstrated a significant reduction of transretinal signaling in animals with repeated DVA (n = 6, p < 0.001).

Conclusions
To the best of our knowledge, this is the first non-invasive study assessing murine retinal vessel response to flicker light with characteristic changes in NVC. The imaging system can be used for basic research and enables the investigation of retinal vessel dimension and function in control mice and genetically modified animals.
Y1  - 2018
U6  - http://dx.doi.org/10.1371/journal.pone.0204689
VL  - 13
IS  - 10
PB  - PLOS
CY  - San Francisco
ER  -