SENSOR DEVICE FOR TARGET PARTICLES IN A SAMPLE

摘要

The invention relates to a sensor device(100) and a method for the determination of the amount of target particles(1) at a contact surface(112) adjacent to a sample chamber(2). Target particles(1) in the sample chamber are detected by a sensor element(SE) and at least one corresponding sensor-signal (s, s') is provided. An evaluation unit(EU) then determines the amount of target particles(1) in a first zone(Z1) immediately at the contracts surface(112) and a second zone(Z2) a distance(z) away from the contact surface based on this sensor-signal. In an optical measurement approach, frustrated total internal reflection taking place under different operating conditions (e.g. wavelength, angle of incidenceq) may be used to extract information about the first and second zones(Z1, Z2). In a magnetic measurement approach, different magnetic excitation fields may be used to excite magnetic target particles differently inthe first and second zone(Z2). Moreover, the temporalcourse of a sensor-signal(s, s') can be evaluated, particularly with respect to stochastic movements ofthe target particles(1).