CMOS image sensor for detection of interferon gamma protein interaction as a point-of-care approach

Abstract

Complementary metal oxide semiconductor (CMOS)-based image sensors have received increased attention owing to the possibility of incorporating them into portable diagnostic devices. The present research examined the efficiency and sensitivity of a CMOS image sensor for the detection of antigen-antibody interactions involving interferon gamma protein without the aid of expensive instruments. The highest detection sensitivity of about 1 fg/ml primary antibody was achieved simply by a transmission mechanism. When photons are prevented from hitting the sensor surface, a reduction in digital output occurs in which the number of photons hitting the sensor surface is approximately proportional to the digital number. Nanoscale variation in substrate thickness after protein binding can be detected with high sensitivity by the CMOS image sensor. Therefore, this technique can be easily applied to smartphones or any clinical diagnostic devices for the detection of several biological entities, with high impact on the development of point-of-care applications.

Overview of CMOS image sensor use in molecular diagnostics

“…CMOS sensor involved in: protein array development for protein diagnosis [32], fluorescence detection for protein and peptide diagnosis [4], CMOS based detection of AgeAb interaction on nanoparticle substrate [6], chemiluminescence analysis for AgeAb diagnosis [33], microarray platform development for DNA, RNA hybridization [16], DNA array development for DNA analysis [34], integrated program for sequence analysis [35], PCR approach for DNA amplification [7], integrated platform for gas sensing [36] optical sensing imager for the bio-molecule detection [37], microscopic approach for biomarker detection [38], and color density analysis for blood glucose monitoring [39]. detection of various AgeAb interactions such as interferon gamma [49], C-reactive protein (CRP) [50], Troponin I [51], HIV [28], and hepatitis B (HBV) [52] and label free electrical detection of hTSH [53]. Also, number of CMOS based cell sensors accomplished the cell monitoring with POC approach [54].…”

CMOS Image Sensor-based Immunodetection by Refractive-Index Change

“…7,8 Our group has tried to develop a simple and highly sensitive diagnostic method based on the CMOS image sensor for the detection of Ag-Ab interactions on indium nanoparticle (InNP) substrates. 1,9,10 Protein adsorption takes place on any surfaces, like glass, metals, nanoparticles, and plastic. However, a protein cannot adsorb on the same protein, itself, without a proper receptor site.…”

“…Also, the present research group has been utilizing InNP substrates for the adsorption of various proteins for their interaction with some specific antibody based on the CMOS image sensor detection method. 1,9,10 Troponin I and C-reactive protein (CRP) are markers of cardiovascular disease, and have been analyzed for heart injury and heart attack. CRP markers are secreted by the liver and released into the blood when a person is injured, or experience inflammation, cancer, heart-related diseases, and viral and bacterial infection.…”

Molecular diagnostics based on smart phone

“…A major advantage of this CMOS image sensor is very cheap electronic device, low power consumption, portability and can be easily incorporated into portable medical diagnostics devices. This CMOS image sensor involved in the immunological analysis by different angle like surface modification [4] and fusion techniques of nanoparticle substrate, and the detection was carried based on the photon sensing method [5,6].…”

“…According to a research report, protein can bind on any substrate like metal (indium, gold, silver) or plastics, but it will not bind together over other proteins [6]. According to this principle, the indium nanoparticle substrates have made by thermal evaporation system.…”