Coagulation measurement from whole blood using vibrating optical fiber in a disposable cartridge

Abstract

, "Coagulation measurement from whole blood using vibrating optical fiber in a disposable cartridge," J. Biomed. Opt. 22(11), 117001 (2017), doi: 10.1117/1.JBO.22.11.117001. Abstract. In clinics, blood coagulation time measurements are performed using mechanical measurements with blood plasma. Such measurements are challenging to do in a lab-on-a-chip (LoC) system using a small volume of whole blood. Existing LoC systems use indirect measurement principles employing optical or electrochemical methods. We developed an LoC system using mechanical measurements with a small volume of whole blood without requiring sample preparation. The measurement is performed in a microfluidic channel where two fibers are placed inline with a small gap in between. The first fiber operates near its mechanical resonance using remote magnetic actuation and immersed in the sample. The second fiber is a pick-up fiber acting as an optical sensor. The microfluidic channel is engineered innovatively such that the blood does not block the gap between the vibrating fiber and the pick-up fiber, resulting in high signal-to-noise ratio optical output. The control plasma test results matched well with the plasma manufacturer's datasheet. Activated-partial-thromboplastin-time tests were successfully performed also with human whole blood samples, and the method is proven to be effective. Simplicity of the cartridge design and cost of readily available materials enable a low-cost point-of-care device for blood coagulation measurements.

Point-of-Care Assessment of Hemostasis with a Love-Mode Surface Acoustic Wave Sensor

“…To overcome these limitations of conventional coagulation monitoring, different kinds of methods have been put forward, such as microcantilever, − magnetoelastic transducer, double clamped sensing beams, vibrating optical fiber, optical coherence elastography, , electrical impedimetric monitor, microfluidic disk analyzer, shear gradient-activated microfluidic device, and so on. To reduce the turnaround time for test results and improve patient care, point-of-care (POC) testing in hematology has attracted significant attention.…”

“…5,6 Despite the advantages of TEG and ROTEM that have been clinically demonstrated through initial applications, such systems still have significant limitations in terms of expensive and complicated equipment, unacceptably long turnaround times, difficulty in miniaturization for personal use, and excessive sample volume (>300 μL) that can be problematic for repetitive assays, especially on pediatric patients. 7 To overcome these limitations of conventional coagulation monitoring, different kinds of methods have been put forward, such as microcantilever, 8−10 magnetoelastic transducer, 11 double clamped sensing beams, 12 vibrating optical fiber, 13 optical coherence elastography, 14,15 electrical impedimetric monitor, 16 microfluidic disk analyzer, 17 shear gradientactivated microfluidic device, 18 and so on. To reduce the turnaround time for test results and improve patient care, point-of-care (POC) testing in hematology has attracted significant attention.…”