EXAMPLES

A selection of the micro-organisms and biomarkers that Ostendum has successfully tested include:

Herpes Simplex Virus type 1 (HSV-1) in buffer and serum

(Left) Herpes Simplex Virus detection test. Sensor signal (phase change) measured between a measuring channel and a reference channel in the interferometric sensor device for the immobilization of Herpes Simplex Virus type 1 (HSV-1) glycoprotein G (gG) monoclonal antibody (α-HSV-1gG) layer on the sensing surface of the measuring channel (ΔΦ α-HSV-1gG) and the binding of HSV-1 particles to this layer (ΔΦ HSV-1);
(Right) Measurement of different HSV-1 concentrations and detection in serum. Phase change measured for different concentrations of HSV-1 sample solutions in PBS, considered to be “very low” to “very high” in terms of the viral load, applied in the measuring channel of the interferometric sensor device. Solid line is a linear-fit of the experimental data, represents the phase change measured for HSV-1 diluted in serum, dashed line indicates the phase detection limit of the sensor (~ 10^-4 fringes).

Listeria bacterium in milk

Listeria detection test.
(Left) Sensor signal measured between a measuring channel and a reference channel in the interferometric sensor device for the immobilization of Listeria antibody layer on the sensing surface of the measuring channel and the binding of different Listeria concentrations in milk to the antibody layer.
(Right) Sensor signal measured for different concentrations of Listeria sample solutions applied in the measuring channel of the interferometric sensor device. Solid line is a linear-fit of the experimental data.

Yeast cells in propagation solution

Yeast cell detection test.
(Left) Sensor signal measured between a measuring channel and a reference channel in the interferometric sensor device for the immobilization of yeast cell antibody layer on the sensing surface of the measuring channel and the binding of different cell concentrations to this layer.
(Right) Sensor signal measured for different concentrations of yeast cell sample solution applied in the measuring channel of the interferometric sensor device. Solid line is a linear-fit of the experimental data.

Benchmarking

Fluorescence microscopy was used to estimate the yeast cell concentration for different dilutions.

Confocal imaging of fluorescently labelled yeast cells.
(Left) fluorescence image. (Right) fluorescence image combined with white light image.

Traumatic Brain Injury (TBI) biomarkers (non-disclosed proteins) in serum

TBI biomarker detection test. Sensor signal measured between a measuring channel and a reference channel for coating of the measuring channel with protein A, the immobilization of anti-TBI biomarker antibody layer on the sensing surface of this channel and the binding of specific TBI biomarker molecules to the antibody layer (TBI). The inset shows in details the binding curve of TBI biomarker.

Antibodies in whey

Antibody detection test. NB. This time the antibodies itself are detected and analyzed, whereas the chip is coated with antigen specific to the antibody of interest. Sensor signal measured between a measuring channel and a reference channel for coating the sensing surface of the measuring channel with an antigen layer and the binding of the specific antibody molecules to the antigen layer (AB).