Layer by Layer Self-Assembly of Immunoglobulins for Piezoelectric Biosensors

The immobilization of two different immunoglobulins by means of the layer by layer self assembly technique (LbL) was studied and evaluated for its use in the development of piezoelectric biosensors. Namely an antibody specific to transforming growth factor pi (anti-TGF-pl) and one specific to taxol were immobilized onto the surface of piezoelectric crystals by the LbL technique and their performance was characterized. The quartz crystal microbalance technique was employed to characterize both the step by step immobilization procedure and the response to the specific analytes. Atomic force microscopy was used to measure the roughness of the crystals before and after immunoglobulin immobilization. The results showed that the proposed immunosensors offer a promising alternative to classical analytical methods for a fast and easy determination of analytes of clinical interest.