A cost-efficient micro fluidic test carrier and easy to store. This requires a sable). Counteracting centrifugal and
enables a dependable quantification of miniaturization of the optic unit and capillary forces are used to transport
different parameter concentrations by therefore, a folding of the light ray path them to different reservoirs without the
analyzing simultaneously optical into the plane of the disc (in-plane- help of pumps and valves and hold them
measurements of dry chemical tests e.g. detection). Optical features such as
in medical practices and intensive care mirrors and shutters are integrated at the
units. For the development of the optical same time as the micro fluidic ones by
measuring and analysis unit different using injection molding.
constraints have to be considered. The
test chemistry is selected in a way that it For the spectroscopic analysis of a para-
reacts optically to the concentration of the meter, two different wavelengths are
parameters measured. Main parameters necessary. In addition to the measuring
wavelength a reference there for defined reaction times. Each
wavelength is used to trial requires only a 10 min measurement
correct the influence of time. This processing includes the
scattering from the test application of the blood sample, the
chemistry on absorption centrifugation of the erythrocytes, and
tests. LEDs are used as a the dosing and aqueous dilution of the
cost-efficient and fast remaining plasma and the dissolution of
modulated illumination the freeze-dried reagents with the
unit. Photodiodes are homogenized sample.
used for the detection.
T h e e n t i r e o p t i c a l
module is thereby loca-
ted on the front part of
the disc. The back part is
left free for the rotary
drive, a carrier for the
d i s p o s a b l e a n d a
temperature control if
needed. The current
design as well includes
an amplifying electronic
unit directly located at
the photodiode to reme-such as cholesterol and hsCRP for risk dy deviations and parasitic errors.assessments of heart attacks can be
determined that way. In order to comply Blood and diluents (buffer) are dosed and with the requirements of an application applied separately to the center of an in the PoC range, both measuring injection molded plastic disc (dispo-instrument and disposable must be small
Optical blood analysesfor cardiac risk diagnostic at the Point-of-CareAuthors:Daniel Rohleder, Dioptic GmbH, Weinheim (Germany)Valérie Winckler-Desprez, Roche Diagnostics GmbH, Mannheim (Germany)Christoph Klaunick, thinXXS Microtechnology AG, Zweibrücken (Germany)
Patient-side Point-of-Care blood analyzing provides lifesaving information in emergency situations. PoC-Tests help to control the progress of major diseases, save time and reduce the effort of the medical staff. The significance of the diagnostic conclusion is increased by analyzing specific combinations of biomarkers at the same time. Therefore, in the German BMBF-funded collaborative project 'µ-Kardio', a fast optical multi-parameters test is developed.
Notice: This is a summary of an article from „BioPhotonik“, special edition 1/2011, April 2011. Approved by the main author, Dr. Rohleder. You will find the complete article at www.bio-photonik.de (webcode B1001)
Detection
Mixing
Measurecircuit withmore than2000 measuringpositions
Microfluidic testting cartridge of thinXXS with dosing in the inner ring, followed by concentric mixing and reaction chambers as well as cuvettes lying outside. The in-plane detection takes place on the yellow marked circle.
Principle of the In-Plane-Detection
Pipette port
Measuringcuvette
vent
reflectingsurfaces
referencecuvette
Layout of a first disposable version for testing the optical functionality in rotation with reflecting surfaces as well as measuring and reference cuvettes.