A microfluidic approach for hemoglobin detection in whole blood

Abstract

Diagnosis of anemia relies on the detection of hemoglobin levels in a blood sample. Conventional blood analyzers are not readily available in most low-resource regions where anemia is prevalent, so detection methods that are low-cost and point-of-care are needed. Here, we present a microfluidic approach to measure hemoglobin concentration in a sample of whole blood. Unlike conventional approaches, our microfluidic approach does not require hemolysis. We detect the level of hemoglobin in a blood sample optically by illuminating the blood in a microfluidic channel at a peak wavelength of 540 nm and measuring its absorbance using a CMOS sensor coupled with a lens to magnify the image onto the detector. We compare measurements in microchannels with channel heights of 50 and 115 μm and found the channel with the 50 μm height provided a better range of detection. Since we use whole blood and not lysed blood, we fit our data to an absorption model that includes optical scattering in order to obtain a calibration curve for our system. Based on this calibration curve and data collected, we can measure hemoglobin concentration within 1 g/dL for severe cases of anemia. In addition, we measured optical density for blood flowing at a shear rate of 500 s-1 and observed it did not affect the nonlinear model. With this method, we provide an approach that uses microfluidic detection of hemoglobin levels that can be integrated with other microfluidic approaches for blood analysis.

Assessment of ROI Selection for Facial Video-Based rPPG

“…PPG is a method of acquiring the pulse waveform of blood vessels noninvasively by using the optical properties of changes in blood vessels on the skin and is used to find out the state of the heartbeat. According to Beer–Lambert’s law [ 3 ], the absorbance of a single compound is proportional to its concentration. Hemoglobin has the highest absorbance at the green wavelength, which is a wavelength of 532 nm and utilizes the characteristic that biological tissue reflects and transmits part of the light when the light source is transmitted through the body.…”

Quantitative absorption imaging of red blood cells to determine physical and mechanical properties

“…3 Low hemoglobin concentration or anemia alone is caused by more than seventeen different diseases. [4][5][6][7][8] Patients with cancer, malaria, HIV/AIDS, hookworm, sickle cell disease (SCD), renal diseases, etc. are prone to anemia.…”

Anemia Diagnosis on a Simple Paper-based Assay

“…A multi-step procedure of scanner based hemoglobin detection method by deploying dried stain of lysed blood on chromatography paper has been reported by Yang et al (10). Taparia et al used PDMS microchannel to detect the level of hemoglobin optically by using a CMOS sensor from diluted blood with calcium-free Tyrode buffer (18). It is undeniable that a significant progress has been made towards the development of a better methodology for point-of-care hemoglobin detection.…”