A portable microfluidic system for rapid measurement of the erythrocyte sedimentation rate

Abstract

The erythrocyte sedimentation rate (ESR) is a frequently used 30 min or 60 min clinical test for screening of several inflammatory conditions, infections, trauma, and malignant diseases, as well as non-inflammatory conditions including prostate cancer and stroke. Erythrocyte aggregation (EA) is a physiological process where erythrocytes form face-to-face linear structures, called rouleaux, at stasis or low shear rates. In this work, we proposed a method for ESR measurement from EA. We developed a microfluidic opto-electro-mechanical system, using which we experimentally showed a significant correlation (R = 0.86) between ESR and EA. The microfluidic system was shown to measure ESR from EA using fingerprick blood in 2 min. 40 μl of whole blood is filled in a disposable polycarbonate cartridge which is illuminated with a near infrared emitting diode. Erythrocytes were disaggregated under the effect of a mechanical shear force using a solenoid pinch valve. Following complete disaggregation, transmitted light through the cartridge was measured using a photodetector for 1.5 min. The intensity level is at its lowest at complete disaggregation and highest at complete aggregation. We calculated ESR from the transmitted signal profile. We also developed another microfluidic cartridge specifically for monitoring the EA process in real-time during ESR measurement. The presented system is suitable for ultrafast, low-cost, and low-sample volume measurement of ESR at the point-of-care.

Update on the Pathomechanism, Diagnosis, and Treatment Options for Rheumatoid Arthritis

“…ESR is a widely used standard laboratory test determining the speed at which erythrocytes settle within a test tube containing a blood sample of the respective patient [159]. In the presence of inflammatory processes, infections, autoimmune disorders (e.g., RA), but also pregnancy, anemia, certain kidney diseases, and some cancers (e.g., lymphoma and multiple myeloma) increased concentrations of fibrinogen in the blood cause a coagulation of the red blood cells (reviewed in [160]).…”

Lab‐on‐a‐Chip Platforms for Disease Detection and Diagnosis

“…), and ionic chemicals (sodium, potassium, etc.) [8,9]. Depending on the type of biomarker as well as the working mechanism of the LOC platform, a number of detection principles can be proposed.…”

A microfluidic erythrocyte sedimentation rate analyzer using rouleaux formation kinetics

“…where w is the channel width and h is the channel height (Isiksacan et al 2016a). Therefore, the width of the PDMS chip was defined according to the width (1 mm) and the height (1 mm) of the channel of the PMMA chip.…”

“…1 (Isiksacan et al 2016a). It consists of a PMMA microfluidic chip and an opto-electro-mechanical analyzer.…”

“…In our previous work, we reported a microfluidic system for the measurement of ESR from aggregation process in 2 min using 40 µl of whole blood (Isiksacan et al 2016a). The system quantifies the rate of rouleaux formation and reports ESR, based on the relationship between ESR and red blood cell aggregation.…”