Quick and reliable diagnosis of non-communicable diseases (NCD) like diabetes, Thyroid disorders etc. is vital especially in developing countries like India where the burden of these diseases is very high. There is a need for portable and cost-effective point-of-care (PoC) testing technologies that provide reliable and rapid results. Lateral flow immunoassay (LFIA) popularly employed in point-of-care (PoC) diagnostics, has strong potential and is a viable option for low-resource settings environments. Traditional LFIA based quantitative instrument requires a motor based motion system to move the test kit in order to measure the results.  We have designed a compact quantitative image-based LFIA reader: ImageQuant Analyzer. It gives a quantitative estimate of the target analyte without any bulky mechanical moving parts which make this easy to maintain LFIA analyzer a truly portable and affordable blood diagnostic instrument.
 

ImageQuant Analyser, the point of care diagnostic instrument based on immunofluorescence was developed by HTIC. It is based upon Lateral flow immunoassay (LFIA) technology. This technology can be used for detection of proteins, vitamin levels (Vit D, Vit B12), hormone levels (TSH, CRP PSA etc.), viral antigens (NS1), infectious diseases (Influenza), and non-communicable disease diagnosis such as HbA1c, D-Dimer, etc. The instrument operates using LFIA dry-chemistry principles. The sample to be analyzed (whole blood or serum) is prepared and mixed with a detection buffer solution (that has the relevant antibodies). Typically in existing LFIA instruments, the reaction at the test and control lines are scanned by illuminating the region using a laser light source and captured using photodiode detecting the fluorescent signals, which also involves mechanical motion system. ImageQuant analyzer, a camera chip based fluorescence imaging technique is utilized to capture entire chemical reaction (i.e. test and control lines) on LFIA test kit in a single shot without moving cartridge in the reader instrument. The captured fluorescence image is processed by a set of customized image processing algorithms developed by HTIC. These algorithms are fully automatic and provide result instantaneously just after scanning the LFIA cartridge. ImageQuant algorithms are highly modular and versatile in order to accommodate a variety of tests designed over LFIA principle without any hardware changes. Each test has a test-specific calibration function (linear line equation, a polynomial function, power equation, 4 parameter logistic, etc.). Calibration function information can be pre-fitted into the instrument or it can be fed to the instrument via various methods such as external calibration chip or a Quick-Response (QR) code sticker provided by the test kit manufacturer.

 

The developed prototype of the ImageQuant instrument and its supporting algorithms were tested extensively in house to quantify the repeatability, reproducibility, and accuracy of the results produced by the instrument. Preliminary results noted are good. The scaled-up prototype development of this instrument is underway and in next six to eight months extensive validation at selected locations in India is planned. The quick and reliable diagnosis of non-communicable diseases (NCD) like diabetes, Thyroid disorders is vital especially in developing countries like India. The compact size and affordability make ImageQuant Analyzer easily deployable PoC instrument on a physician’s desk or in-home testing which can create a huge impact on reducing the burden of NCDs in India and other developing countries.