Impedance based living cell analysis for clinical diagnosis of type I allergy

A novel tool for clinical diagnosis of allergy operating a microfluidic immunoaffinity basophil activation test technique

“…Other microfluidic tests for detection of cell degranulation has been seen to be quite sensitive using e.g. impedance measurements, even though it has not been proven to work with human basophils from blood yet [147]. Impedance measurements was able to detect even slight changes in morphology, which might be due to e.g.…”

“…This negative charge can be used to detect degranulation using impedance measurements in a microfluidic chip. The negative charge was detected using fluorescently labelled avidin, which binds to strong negative charge and has been used to detect degranulation of rat basophil cell line after incubation with patient serum followed by antigen stimulation [147].…”

“…To our knowledge, there are at present no other microfluidic techniques capable of capturing and stimulating human basophils from whole blood. Most microfluidic assays are developed using basophil cell line, such as the CD-based platform lab-on-a-disc (LOAD) [142,143] and the impedance measurements of the negative charge from degranulation in a microfluidic chip [147]. Surface plasmon resonance (SPR), detects changes in refractive index in captured cells and has been used to study the degranulation of captured human basophils from blood, but after prior purification steps [146].…”

Functional blood cell analysis by label-free biosensors and single-cell technologies

“…The activation was inhibited in the presence of various inhibitors as expected [212]. Subsequently, the application of this system was expanded to other cell types, primary basophils [213] and serum testing using a modified RBL-2H3 clone expressing human IgE receptor (FcεRI) [214], optical fiber SPR based detection [215], later adapted to impedance-based assays [216], and most importantly to single cells [217]. Most recently with a combined impedance and SPR based measurement, they showed that results of the combined measurements show similar outcomes and activation of the cells [218].…”