Fiber optik tabanlı kartuş ile çalışan taşınabilir kan pıhtılaşma zamanı ölçüm platformu

Advancements in sensor technologies have enabled miniaturized point-of-care (PoC) medical diagnostics devices and offer new opportunities in health care. Most of the new sensor platforms and lab on chip devices are still at laboratory level with only a few successful PoC implementations such as blood glucose monitoring devices. In this thesis, we focused on the development of a novel optical sensor platform and PoC device for periodic monitoring of blood coagulation, which is a critical need for cardiac patients on anticoagulant treatment. While the golden standard for coagulation measurements is direct mechanical measurement from plasma in clinical laboratories, existing commercial and research phase PoC devices employ electro chemical and MEMS based lab on chip devices. This is the first report of a direct mechanical coagulation time measurement system designed for self-testing. The proposed platform has two parts; a disposable cartridge and a reader unit. Disposable cartridge has small volume microfluidic channels for blood flow and fiber optic based mechanical sensor. This sensor is composed of two optical fibers facing each other. One of the fibers is vibrated in mechanical resonance via an electro coil embedded in the reader unit. The other fiber is fixed and receives the light passing through the vibrating fiber. An optical AC signal is obtained at the output of the fixed fiber due to mechanically induced optical modulation. The reader unit has an LED light source coupled to the large core of the vibrating fiber, and a photodetector coupled to the the fixed fiber. Lack of electrical connection to the cartridge, remote electromagnetic actuation and optical read out enable simple and robust POC platform. The proposed sensor platform is tested on a table top measurement set-up for activated-Partial-Thromboplastin-Time (aPTT) measurements on control plasma samples and human whole blood samples. Control plasma test results yielded <1% mean error and <1.36% relative standard deviation based on repeated tests. Then aPTT tests were successfully carried out with human whole blood samples. Proposed platform showed robust and repeatable results in both plasma and whole blood samples. A portable prototype based on table top measurement set up was developed in collaboration with SFO Technologies, India. aPTT test capability of the prototype was also demonstrated with human whole blood. Simplicity of the cartridge design and use of readily available materials enables low cost disposable cartridge and reader units. Future work will focus on reagent optimization, portable reader design, and validation of the system in clinical tests.