New Plasmonic Biosensors for Determination of Human Hemoglobin Concentration in Blood

New Plasmonic Biosensors for Determination of Human Hemoglobin Concentration in Blood:

Abstract

Two new types of plasmonic biosensors are applied for detection of hemoglobin concentration in human blood by using the angular interrogation method. The first type of the fiber with five layers is made by a SiO₂ core surrounded by GaP, gold, Al₂O₃ and hemoglobin layers. The second type of the fiber with six layers is made by a ZBLAN core surrounded by NaF, silicon, silver, Al₂O₃ and hemoglobin layers. For some thicknesses of the interior layers and for a hemoglobin concentration close to the mean value of a male human at a laser wavelength (1.53 μm), a large figure of merit and maximum value of the amplitude sensitivity are obtained at an angle very close to the resonance angle. For the second type of the sensor, 0.0036 g/dl resolution is obtained, which is 10% finer than the estimated detection limit (0.004 g/dl) reported very recently by using an electrochemical method. Also, our resolution is better than the previously reported value (0.006 g/dl if the angular resolution is 0.001°) by using a gold–aluminum-based surface plasmon resonance sensor.