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Here, we report a new pentafluoropropanamido rhodamine fluorescent probe (ACS-HNE) that allows for the selective detection of neutrophil elastase (NE). ACS-HNE displayed high sensitivity, with a low limit of detection (

1 Point-of-Care Biosensor Systems their applications as diagnostic tools for health care||2 Instrumentation and Characterization||3 Synthesis, Photophysical Characterization and Binding Interactions of Far Red Sensitive Symmetrical Squaraine Dyes with BSA||4 Synthesis, Photophysical Characterization and Binding Interactions of Unsymmetrical Cyanine Dyes with BSA||5 Near Infrared Fluorescence Detection of Elastase Enzyme Activity Using Peptide-Bound Unsymmetrical Squaraine Dye, Easy and fast detection of diseases is now demand of time for monitoring the health conditions and sustaining the ever-improving lifestyle in both of the developed as well as developing countries. Biosensors are analytical devices that transform a biological response into an electrical signal. Biosensors are extremely specific and are independent of physical parameters such as pH and temperature and should be ecofriendly. Development of biosensors such as enzyme sensors, immune-sensors, microbial sensors, ion channel sensors etc. is one of fast growing sectors and is being actively promoted world-wide. Some of the most commonly used biosensors include Enzyme sensors for the measurement of blood glucose level using glucose oxidase activity measurement, immune-sensors and ELISA. Since detector is one of the important part of biosensors, fluorescence detection has a great potential for the detection of trace amount of analytes due to high sensitivity measurement as compared with the optical absorption especially for very dilute samples. Fluorescent biosensors plays a key role in discovery of drugs and in cancer. Single chain FRET biosensor is potential example which consists of a pair of auto fluorescent protein （AFP`s） where fluorescence resonance energy transfer occurs between them when brought close together. Conventionally, FRET based biosensor using visible fluorescent molecules is influenced by auto-fluorescence from the clinical samples like blood, serum or other body fluids leading to low signal to noise （SN） ratio and attainment of high sensitivity is hampered significantly. A FRET biosensor utilizing NIR fluorescent and quenchers can easily detect resulting fluorescence signals from the body of several 10 cm from a detector outside the body with high SN ratio （high sensitivity）. This means that it is very suitable for pathological imaging in vivo. In order to increase the sensitivity of the biosensor using near infrared FRET, it is desirable that the wavelengths of the dye absorption and fluorescence emission should perfectly match. It is also necessary to adjust the peptide sequence of the enzyme active site so that the position of the quenching group and the fluorescent group are within the Forster radius. Protein and peptide biosensors are manufactured easily through synthetic chemistry followed by enzymatic labelling using synthetic fluorophores. A biosensor based on NIR-FRET system is advantageous for high sensitivity in terms of not being easily influenced by auto-fluorescence of water or biomolecules and high penetrability of near infrared rays. At the same time, by changing the peptide sequence between the dyes having fluorescent groups and quenching groups in different wavelength ranges, it is possible to control the absorption wavelength specifically for the enzyme. This means that simultaneous measurement of multiple specimens is possible, and the detected image leads to the construction of a disease database enabling multifaceted examination as a disease pattern and diagnosis with higher accuracy. By immobilizing to the substrate, it can be applied to onchip biosensor in-vitro too. Fluorescent biosensors are potentially employed for early detection of biomarkers in clinical and molecular diagnostics for disease progress monitoring and response to treatment. In the development of near infrared FRET biosensor, development of NIR dyes （fluorescent group and quenching group） and design of enzyme recognition site are necessary. Current thesis gives the insights about the synthesis and characterization of far-red sensitive squaraine dyes with varying wavelengths and NIR cyanine dyes. Apart from this, an effort has been made to evaluate amino acid sequences that are selective for specific enzymes and incorporating them to develop model NIR-FRET system., 九州工業大学博士学位論文 学位記番号：生工博甲第301号 学位授与年月日：平成29年9月22日, 平成29年度