5/8/2020 Irox 2000 Manual
PHYSICIAN’S LEAD MANUAL Implantable Lead CAUTION: Federal law restricts this device to sale by or on the. (IROX ™) titanium tip electrode and a platinum iridium anode. 2000, involved 461 devices implanted in 238 patients (mean implant duration was 7.5 months, range 0.1 to 12.5 months). Manuals and free instruction guides. Find the user manual.
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US9163313B2 - Amorphous IrOX film pH sensor- Google Patents US9163313B2 - Amorphous IrOX film pH sensor- Google Patents Amorphous IrOX film pH sensorInfo Publication number US9163313B2 US9163313B2 US14/037,848 US48A US9163313B2 US 9163313 B2 US9163313 B2 US 9163313B2 US 48 A US48 A US 48A US 9163313 B2 US9163313 B2 US 9163313B2 Authority US United States Prior art keywords ph sensor layer iridium oxide electrode Prior art date 2008-02-13 Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.) Active, expires 2029-06-19 Application number US14/037,848 Other versions Inventor Jung-Chi Chiao Wen-Ding Huang Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)University of Texas SystemUniversity of Texas at ArlingtonOriginal Assignee University of Texas System Priority date (The priority date is an assumption and is not a legal conclusion. The present invention provides a pH sensing apparatus that includes a flexible polymer substrate, one or more amorphous iridium oxide film sensor electrodes disposed on the flexible polymer substrate, and a reference electrode corresponding to each amorphous iridium oxide film sensor electrode. Each reference electrode is disposed on the flexible polymer substrate in close proximity to the corresponding amorphous iridium oxide film sensor electrode. The amorphous iridium oxide film sensor electrodes provide a potential in reference to the reference electrodes that varies according to a pH of a substance contacting the amorphous iridium oxide film sensor electrodes and the reference electrodes. CROSS REFERENCE TO RELATED APPLICATIONSThis application is a divisional of U.S.
Application Ser. 12/911,329, filed Oct. 25, 2010, now issued as U.S. 8,552,730, which is a continuation-in-part of U.S. Application Ser. 12/867,526, now abandoned, which is a national phase of International Application No. PCTIUS1 filed Feb.
13, 2009, which claims benefit of Provisional Application No. 61/028,343, filed Feb. 13, 2008, the content of which is expressly incorporated herein by reference. FIELD OF INVENTIONThe present invention relates in general to the field of sensors, and more particularly to an amorphous iridium oxide film pH sensor. BACKGROUND ARTpH sensors are used in clinics, laboratories and industrial factories since many biological and chemical reaction mechanisms are pH dependent.
Conventional glass-type electrodes have been widely used; however, they still have certain disadvantages in specific applications. The glass rod sensor configuration is difficult to use for in vivo biomedical, clinical or food monitoring applications due to the brittleness of glass, size limitations and the lack of deformability. To achieve small sizes and robust design, ion-sensitive field-effect transistor (iSFET) pH sensors 1-5, optical fiber pH sensors 1, 6-11, hydrogel film pH sensors 12-14, and solid sate pH sensors 1, 15-18 have been proposed. ISFET sensors have power consumption concerns due to the field-effect transistor (FET) operational requirements 19. Hydrogel film pH sensors utilize the physical properties of the pH-response swelling and shrinking polymer to measure resistance changes 12. The sensor structure design and polymer layer fabrication process can be complicated and expensive 13. Optical pH sensors also have power consumption issues due to the use of light sources.
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The system including optical devices could be expensive and unsuitable for implantation 1, 7-8, 10-11.Various solid-state metal oxides have been investigated for pH sensing electrodes 1, 15 including PtO 2, IrO x, RuO 2, OsO 2, Ta 2O 5, RhO 2, TiO 2 and SnO 2 as the pH sensing films. The pH sensitivity, selectivity, working range, and hysteresis indicate sensing performance. IrO x, RuO 2 and SnO 2 have been demonstrated with more advantages in sensor performance for various applications 22. RuO 2 18, 20 and SnO 2 21 show near Nernstian responses in wide pH ranges. However, SnO 2 and RuO 2 presented hysteresis and drift problems leading to potential calibration issues and unstable responses 20, 21. Iridium oxide film (IROF) has performed outstanding stability over wide pH rages, rapid responses, less hysteresis and high durability, which have also been demonstrated at high temperature up to 250° C. 23.There are different fabrication methods for IROF including sputtering deposition 23, 24, electrochemical deposition 25-29, thermal oxidation 23, and sol-gel 30-32 processes.
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The sputtering iridium oxide film (SIROF) deposition process is costly due to the target cost. The oxygen and argon pressure ratios, position of the target, deposition rate, and RF powers during the fabrication processes all affect the pH sensing parameters such as potential drifts and redox interference 22. Anodic electrochemical deposition presents an economical way for iridium oxide thin film fabrication. The anodic iridium oxide thin film (AIROF) process is based on electrolysis of a solution containing iridium complexes.
The iridium tetrachloride compound has been widely used as a deposition agent 26-29 such as the commonly used Yamanaka solution 26. The pH value of the deposition solution, solution temperature and current density control affect the deposition efficiency 26-29. A precise power supply system as potentiostate is required in the electro-deposition process for thickness and film quality control. For thermal oxidation process, it requires a high temperature ranging from 500 to 800° C. The film made by thermal oxidation can be thicker than the AIROF with more stable potentials 22, 23. However, the film surface has a tendency to crack after the high temperature treatment.
The adhesion property of the cracked film then becomes an issue. The high temperature treatment also becomes a limitation during sensor fabrication, especially for the use of polymer and photoresist, which often can not survive at a temperature above 200° C. The sol-gel IROF deposition process has been demonstrated 32 with dip coating 32, 33 and heat treatment 31, 32 procedures.
Sol-gel deposition provides a simpler and economical fabrication approach.There is, therefore, a need for a cost efficient, simpler fabrication and lower power consumption, a metal-oxide pH sensor with deformability on a flexible substrate. SUMMARY OF THE INVENTIONThe present invention provides a sol-gel process to make IROF pH sensor arrays on flexible polyimide substrates. An amorphous and uniform IROF was formed with 300° C. Thermal oxidation, Our IROF pH sensor provided good stability with less drifts, high selectivity, fast response, reversibility with low power consumption advantages along with the simpler and potentially lower cost fabrication processes. With these features, our sensors could be used for in vivo biomedical 34, 35, biological 36, 37, clinical 38-40, food monitoring 41, 42 and lubricant applications 43.Both iridium oxide sensing films and Ag/AgCl reference electrodes were formed on a polyimide flexible substrate by sol-gel, dip-coating and thermal oxidation processes.
Fabrication, characterization, and dynamic test results of a deformable potentiometric pH electrode were presented. The IrO x pH sensors exhibited promising sensing performance with a super-Nernstian response of sensitivity between 69.6 and 71.6 mV/pH in the pH range from 1.9 to 12 at 25° C. A response time was obtained at less than 7 seconds. The pH electrodes showed high selectivity and reversibility in different acid and alkaline solutions.
The deformable pH electrodes provide the advantage of accommodating sensors in small spaces or conform to curved surfaces. Our deformable pH sensor array responded with distinct potentials to various pH values at different positions inside a 1.5-cm diameter tube.The present invention provides a pH sensing apparatus that includes a flexible polymer substrate, one or more amorphous iridium oxide film sensor electrodes disposed on the flexible polymer substrate, and a reference electrode corresponding to each amorphous iridium oxide film sensor electrode. Each reference electrode is disposed on the flexible polymer substrate in close proximity to the corresponding amorphous iridium oxide film sensor electrode. A first electrical contact pad corresponding to each amorphous iridium oxide film sensor electrode is disposed on the flexible polymer substrate and electrically connected to the corresponding amorphous iridium oxide sensor. A second electrical contact pad corresponding to each reference electrode is disposed on the flexible polymer substrate and electrically connected to the corresponding reference electrode.
What is the best location for a weather station and its sensors? Verified The weather station itself is placed inside and needs to be kept away from heat sources such as the kitchen, windows or electrical appliances. A separate outside temperature sensor needs to placed in shadow and at least 1,25m above the ground. A rain sensor needs to be placed in an open area where it can always collect rain. A wind sensor needs to be placed in an open area too, with any obstacles influencing the wind.This was helpful ( 47).
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