Patent Application
20090020423
1. Field of the Invention
The present invention generally relates to magnesium ion sensor and fabrication method, and more particularly to potentiometric magnesium ion sensor and fabrication method.
2. Description of the Prior Art
For hygiene, the concentration of Mg2+ is one of the most important parameter in the clinical assay, the Mg2+ activity in blood serum was shown to decrease during liver transplantation due to accumulation of citrate and concomitant chelation of Mg2+. A low Mg2+ activity has been observed in patients suffering from acute migraine, headaches and cardiac diseases. The disadvantage of traditional potentiometric Mg2+ devices are expensive and hard to fabricate. In order to make the measurement of magnesium ion easily, magnesium ISEs (Ion-selective electrode) have been developed in this invention.
Therefore, in accordance with the previous summary, objects, features and advantages of the present disclosure will become apparent to one skilled in the art from the subsequent description and the appended claims taken in conjunction with the accompanying drawings.
A potentiometric magnesium ion sensor and fabrication method is disclosed. At first, a conduction layer is formed on a substrate. Then, a SnO2 thin-film is deposited on the conduction layer by radio frequency sputtering method, and the conduction layer, the SnO2 thin-film and a conducting line are connected by a conduction paste. Thereupon, an insulation layer is formed, wherein the conduction layer, the SnO2 thin-film and one end of the conducting line are coated with the insulation layer, and an opening of the insulation layer is formed on the SnO2 thin-film. Finally, a magnesium ion-selective membrane is formed by dropping the material of the magnesium ion-selective membrane on the opening.
The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present invention, and together with the description serve to explain the principles of the disclosure. In the drawings:
The present disclosure can be described by the embodiments given below. It is understood, however, that the embodiments below are not necessarily limitations to the present disclosure, but are used to a typical implementation of the invention.
Having summarized various aspects of the present invention, reference will now be made in detail to the description of the invention as illustrated in the drawings. While the invention will be described in connection with these drawings, there is no intent to limit it to the embodiment or embodiments disclosed therein. On the contrary the intent is to cover all alternatives, modifications and equivalents included within the spirit and scope of the invention as defined by the appended claims.
It is noted that the drawings presents herein have been provided to illustrate certain features and aspects of embodiments of the invention. It will be appreciated from the description provided herein that a variety of alternative embodiments and implementations may be realized, consistent with the scope and spirit of the present invention.
It is also noted that the drawings presents herein are not consistent with the same scale. Some scales of some components are not proportional to the scales of other components in order to provide comprehensive descriptions and emphasizes to this present invention.
Please refer to
The substrate 110 could comprise glass, and the conduction layer 120 could comprise Indium Tin Oxide (ITO). The insulation layer 150 could comprise Epoxy, and the conduction paste could comprise silver paste. The magnesium ion-selective membrane 160 consists of magnesium ionophore, K-TpClPB, plasticizer, and Poly (vinyl choride). Moreover, the performance was exhibited by the magnesium ion-selective membrane having magnesium ionophore:K-TpClPB: plasticizer:Poly(vinyl choride) in the weight ratio (wt %) 1.40:1.00:64.50:33.10.
However, the
Also as noted above, the potentiometric magnesium ion sensor 100 further includes the above-mentioned conducting line 140, wherein one end of the conducting line 140 is connected to the conduction layer 120 and the SnO2 thin-film 130, and the conduction layer 120, the SnO2 thin-film 130 and the conducting line 140 could by the conduction paste, which could be silver paste.
The potentiometric magnesium ion system 170 is shown in
The amplifier is electronically coupled with the conduction layer 120 by the conducting line 140, wherein one end of the conducting line 140 is connected to the conduction layer 120 and the SnO2 thin-film 130, and the other end of the conducting line 140 is connected with the amplifier 174 by passing through the insulation layer 150. Moreover, the digital multi-meter 176 is electronically coupled with the amplifier 174, and measures the output signals from the amplifier 174 to output measurement values. Then, the computer 178 is electronically coupled with the digital multi-meter 176 for computing the measurement values from the digital multi-meter 176.
The potentiometric magnesium ion sensor 100 and the reference electrode 172 are immersed into a butter solution 180, and the reference electrode 172 is held out at a reference potential. When magnesium ions pass through the magnesium ion-selective membrane 160 to react with the SnO2 thin-film 130, the potentiometric magnesium ion sensor 100 would output a signal according to a potential difference between the potentiometric magnesium ion sensor 100 and the reference electrode 172.
The signal from the potentiometric magnesium ion sensor 100 is immediately transmitted to the digital multi-meter 176 and the computer 178 by the amplifier 174, and the concentration of the magnesium ions in the buffer solution 180 is measured and analyzed by the digital multi-meter 176 and the computer 178.
According to the experimental results, the sensitivity of the potentiometric magnesium ion sensor 100 is about 31.71 mV/decade when the concentration range of the magnesium ions is between 1×10-4 M and 0.1 M, and measurement time is about 30 seconds. Besides, the relations between the concentration of the magnesium ions and the potential are shown in
The foregoing description is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obvious modifications or variations are possible in light of the above teachings. In this regard, the embodiment or embodiments discussed were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the inventions as determined by the appended claims when interpreted in accordance with the breath to which they are fairly and legally entitled.
It is understood that several modifications, changes, and substitutions are intended in the foregoing disclosure and in some instances some features of the invention will be employed without a corresponding use of other features. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention.
