Detection of Influenza A by Surface Plasmon Resonance Enhanced Total Internal Reflection Ellipsometry

In this paper, label free detection of Influenza A by using Surface Plasmon Resonance enhanced Total Internal Reflection Ellipsometry (SPRe-TIRE) method was discussed. Besides the other surface plasmon resonance based applications, TIRE (i.e., ellipsometric measurements) has unique advantages and was used for real-time liquid phase detection. A micropatterned sensor surface was also implemented in to study in order to determine the possibility of array platforms in SPRe-TIRE configuration. A single-strand oligodeoxynucleotide (ssODN), carrying a thiol end group which is complementary of the characteristic sequence of Influenza A (i.e., target) was immobilized onto SPRe-TIRE chip surface via self assembly technique. Non-complementary ssODN was also used to determine selectivity. Overlayer formation (as layer thickness) by ellipsometric measurements and sensor responses by SPRe-TIRE measurements were reported. A linear sensor response was obtained in 0.05 mu M-2 mu M target range. 50 nM synthetic target sequence was detected successfully by using suggested technique.