Optical Techniques
One such example is that of liquid crystal (LC) based optical sensor for
highly sensitive endotoxin detection. LC based optical biosensors are
developed using endotoxin specific single-stranded DNA aptamers which
are the endotoxin selective probes of the biosensors. The LC based
aptamer optical biosensors have linear endotoxin detection range from
0.005 to 100 ng/ml and a detection limit of 5.5 pg/ml. The biosensors
have negligible cross-binding reactivity with the biomolecules thus
maximizing their recovery 94. Broadly, these optical
techniques can be divided into three distinct categories: luminescence,
Surface Plasmon Resonance, and electrochemiluminescence that share the
similar characteristic of relying on visual changes.