Abstract: A potentiometric Mg2+ sensor is disclosed, wherein the potentiometric SnO2/ITO-based Mg2+ ISE was developed in this invention. The magnesium ion-selective membrane was fabricated and dripped on the surface of SnO2. The performance, such as sensitivity, was exhibited by the magnesium ion-selective membrane having magnesium ionophore, K-TpClPB, plasticizer, PVC in the suitable ratios. Moreover, the Mg2+ ISE was measured in different Mg2+ concentration buffer solutions. According to the experimental results, the best sensitivity of the Mg2+ sensor is 31.7l mV/decade between 10-4M and 10-1M, and measurement time is 30 sec.

Abstract: A solid-state urea biosensor may comprise a substrate, an electrically conductive layer, a PH sensing film, an ammonium ion selecting film and a ferment film. The electrically conductive layer covers the substrate. The PH sensing film has a PH value measuring zone, partially covering the electrically conductive layer, for measuring the PH value of a solution to be tested. The ammonium ion selecting film has an ammonium ion measuring zone for measuring the ammonium ion concentration. The ammonium ion selecting film partially covers the PH sensing film and exposes the PH value measuring zone. The ferment film is used for measuring the urea concentration in the solution, wherein the ferment film partially covers the ammonium ion selecting film and exposes the ammonium ion measuring zone.

Abstract: This invention discloses a voltage-type gas concentration sensor and sensing method thereof. An ionic sensing electrode, a solid electrolyte membrane and a gas-permeable membrane are provided. The ionic sensing electrode comprises a sensing window. The solid electrolyte membrane is disposed on the sensing window. The gas-permeable membrane is disposed on the solid electrolyte membrane. By detecting the change of a reaction voltage as a result of reaction between the ionic sensing electrode and a solution to be measured, the invention is able to determine the pH of the solution to be measured.

Abstract: A multi-ion potential sensor is disclosed. The multi-ion potential sensor comprises a substrate, a conductive layer, an isolation layer, a tin oxide (SnO2) layer and a selective layer. The conductive layer comprises a plurality of independent conductive areas, wherein every conductive area comprises a readout area, a transmissive area and a sensing area, and the transmissive area of every conductive area is packaged by the isolation layer. The tin oxide layer comprises a plurality of independent tin oxide areas, wherein every tin oxide area is deposited on the sensing area, and the selective layer comprises a plurality of independent selective areas, wherein every selective area is set on the tin oxide area. The multi-ion potential sensor has various advantages, such as good sensitivity, low cost, simplicity, disposable, portable and data acquisition by a computer for different applications.

Abstract: The present invention discloses an optical sensor for measuring blood gas, used to measure gas concentration in a liquid, comprising: an indicator solution; a first conduit for filling with the indicator solution wherein the first conduit passes through the liquid and the gas in the liquid can diffuse into the first conduit to react with the indicator solution so as to change the color of the indicator solution; a second conduit for receiving the reacted indicator solution in the first conduit; and a light emitter and a photodetector provided in opposition to each other at the two sides of the second conduit wherein the light emitter emits light towards the second conduit and the photodetector receives the light passing through the second conduit and the reacted indicator solution and thereby outputs a sensing signal depending on the received light intensity.

Abstract: An alkaloid sensor, systems comprising the same, and measurement using the systems. The alkaloid sensor has an extended gate field effect transistor (EGFET) structure and comprises a metal oxide semiconductor field effect transistor (MOSFET) on a semiconductor substrate, a sensing unit comprising a substrate, a tin oxide film on the substrate, and an alkaloid acylase film immobilized on the tin oxide film, and a conductive wire connecting the MOSFET and the sensing unit.

Abstract: An alkaloid sensor, systems comprising the same, and measurement using the systems. The alkaloid sensor has an extended gate field effect transistor (EGFET) structure and comprises a metal oxide semiconductor field effect transistor (MOSFET) on a semiconductor substrate, a sensing unit comprising a substrate, a tin oxide film on the substrate, and an alkaloid acylase film immobilized on the tin oxide film, and a conductive wire connecting the MOSFET and the sensing unit.

Abstract: A moisture-sensitive element with an interdigital capacitor (IDC) and fabrication thereof are disclosed, wherein the moisture-sensitive element with the interdigital capacitor investigates a moisture sensor for the determination of human skin moisture based on the interdigital capacitor. The moisture-sensitive element with an interdigital capacitor comprises a printed circuit board (PCB), an interdigital capacitor formed on the printed circuit board, and a moisture sensing layer formed on the interdigital capacitor.

Abstract: A method for fabricating an array pH sensor and a readout circuit device of such array pH sensor are implemented by utilizing an extended ion sensitive field effect transistor to construct the array pH sensor and related readout circuit. The structure of the array sensor having this extended ion sensitive field effect transistor comprises a tin dioxide/metal/silicon dioxide multi-layer structure sensor and a tin dioxide/indium tin oxide/glass multi-layer structure sensor and has excellent properties. Furthermore, the readout circuit and the sensor utilize two signal generators for controlling and reading signals. In particular, the sensor can be effective for increasing the accuracy of measurement and reducing the interference of noise.

Abstract: A ruthenium oxide electrode. The ruthenium oxide electrode includes a substrate, a ruthenium oxide film formed thereon, and a conductive wire connecting to the ruthenium oxide film. The invention also provides a method of fabricating the ruthenium oxide electrode.

Abstract: An optical gas concentration sensor and method for measuring blood gas based on the light adsorption sensing technique are disclosed. The optical gas concentration sensor comprises a light source, a photo detector, and a gas filtering membrane for separating the indicator and a liquid. A gas in the liquid diffuses to the indicator through the gas filtering membrane so as to change the color of the indicator due to the chemical reaction occurred between the indicator and the gas. Then, the photo detector receives the light passing though the reacted indicator from the light source. The gas concentration is determined based on pH-sensitive absorbance spectrum of the indicator.

Abstract: A titanium oxide extended gate field effect transistor (EGFET) device and fabricating method thereof. Titanium oxide is formed on an EGFET by sputtering, coating a detection membrane therefor. Current-voltage relationships at different pH values are also measured via a current measuring system. Sensitivity parameter of the titanium oxide EGFET is calculated according to a relationship between a pH value and a gate voltage.

Abstract: A PbTiO3/SiO2-gated ISFET device comprising a PbTiO3 thin film as H+-sensing film, and a method of forming the same. The PbTiO3 thin film is formed through a sol-gel process which offers many advantages, such as, low processing temperature, easy control of the composition of the film and easy coating over a large substrate. The PbTiO3/SiO2 gated ISFET device of the present invention is highly sensitive in aqueous solution, and particularly in acidic aqueous solution. The sensitivity of the present ISFET ranges from 50 to 58 mV/pH. In addition, the disclosed ISFET has high linearity. Accordingly, the disclosed ISFET can be used to detect effluent.

Abstract: A titanium oxide extended gate field effect transistor (EGFET) device and fabricating method thereof. Titanium oxide is formed on an EGFET by sputtering, coating a detection membrane therefor. Current-voltage relationships at different pH values are also measured via a current measuring system. Sensitivity parameter of the titanium oxide EGFET is calculated according to a relationship between a pH value and a gate voltage.

Abstract: The invention provides a method of fabrication of a solid-state urea biosensor and its data acquisition system. The biosensor includes a substrate, and three individual sensing areas separated by an insulating layer on the substrate. Each individual sensing area contains a conductive layer on the substrate, and a pH sensitive membrane is deposited thereon. An enzyme layer is deposited on one of the pH sensitive membranes to form a working electrode. The other two sensing areas are a quasi-reference electrode and a contrast electrode, respectively. The sensing signals are transferred to an instrumentation amplifier by conductive wires. The sensing signals are then transferred to a low-pass filter to reduce the high frequency noise. A data acquisition card is employed to transfer the sensing signals to a computer. The sensing signals are analyzed by the program of the data acquisition system. The data are then displayed on the display panel.

Abstract: A multi-functional PH meter and the fabrication thereof are disclosed. The multi-functional pH meter immediately displays the measurement result on a liquid crystal display and saves in a compact flash card so as to provide portable functionality. In addition, the multi-functional pH meter has data communication functionality with a computer. Finally, the drift and hysteresis software calibration technique is applied. Thus, this method can increase ion detection accuracy and system reliability. The multi-functional pH meter includes a sensor unit, an analog signal processing unit, a microprocessor unit, the liquid crystal display unit, the compact flash card unit and a data transmission unit.

Abstract: A system of measuring pH of a solution having a calibration device to counteract time-drift effect. The calibration device of the system adjusts a compensation voltage to zero a measuring voltage of a first sensor and only respond to time-drift voltage of the first sensor. The calibration device has a differential operation amplifier receiving measuring voltages from the first sensor and a second sensor of the system to eliminate the time-drift voltages of the first and second sensors, thereby achieving calibration of the time-drift effects.

Abstract: A multi-functional PH meter and the fabrication thereof are disclosed. The multi-functional pH meter comprises a sensor unit, an analog signal processing unit, a microprocessor unit, a liquid crystal display unit, a compact flash card unit and a data transmission unit. The sensor unit includes an electrode, a substrate, an indium tin oxide film on the substrate, a sensing film on the indium tin oxide film and connecting to a conductive wire, a package material covering the sensing film, the indium tin oxide film and a portion of the substrate and exposing the sensing film via a sensing window. The analog signal processing unit processes analog signals from the sensing unit via the conductive wire. The microprocessor unit receives the signals from the analog signal processing unit and generates a pH value of a solution being detected. The liquid crystal display unit displays the pH value and the compact flash card unit saves the pH value.

Abstract: An ion solution concentration-detecting device includes a working electrode, a reference electrode and a replaceable link element. The reference electrode includes a polymeric membrane with ion material covering silver/silver chloride (Ag/AgCl) electrode to provide a fixed and stable electrical potential. The working electrode usually is a contact-detecting electrode having a sensing membrane. The sensing membrane may be a metal oxide or a polymer with ion material for measuring different ion solution effectively. For the better sensitivity to the different ion solution, the working electrode bond with the replaceable link element is replaceable. The working electrode being a contact-detecting electrode can be replaced by another contact-detecting electrode with different sensing membrane.

Abstract: A wireless pH measurement system is disclosed, the wireless pH measurement system includes a portable module and a receiver end. The portable module comprises a signal detecting and processing portion and a wireless transmission portion. The signal detecting and processing portion comprises a sensor unit for detecting a pH signal, amplifying, filtering noise, analog/digital conversion and numerical processing to generate a pH measurement signal. The wireless transmission portion receives the pH measurement signal via a transmission interface and transmits by a Bluetooth module. The receiver end includes a Bluetooth receiver for receiving the pH measurement signal. The receiver end processes the pH measurement signal by programs, displays, analyzes and stores the pH measurement signal and transmits warning signal when an abnormal pH measurement signal is received.