Disposable HSA QCM-immunosensor for practical measurement in liquid

The application of quartz crystal microbalance (QCM) as affinity immunosensor of human serum albumin (HSA) has been investigated. The aim of the investigation was the development of a sensor for simple use for physicians in practice. The HSA immunosensors were constructed as a disposable immunosensor based on a cost effective QCM sensor. A self mixing cell without pumping system was constructed together with the QCM-immunosensor for easy handling. The HSA antibody was immobilized on top of a quartz resonator coated with a mixture of polystyrene and p-tert-butyl-calix[8]arene. There were no significant differences between the measured maximum frequency change of off-line measurement in air and on-line measurement in PBS. In this experiment, the developed immunosensor allows the measurement of HSA in PBS in the concentration range from 1 to 250 μg/ml. The limit value concentration of 20 μg/ml between ill and healthy condition can be well measured. The sensor shows a selectivity to HSA in urine.