Summary of the invention
The main technical problem to be solved in the present invention is, a kind of bio-sensing test macro is provided, and can effectively improve the bio-sensing measuring accuracy.
For solving the problems of the technologies described above, the present invention has adopted following technical scheme:
The invention provides a kind of bio-sensing test macro, comprise the bio-sensing test-strips and cooperate with described bio-sensing test-strips and the bio-sensing tester that carries out the bio-sensing test that described bio-sensing test-strips comprises first test electrode, first conductive channel that is communicated with first test electrode, second conductive channel, second test electrode, the 3rd conductive channel that is communicated with second test electrode, the 4th conductive channel; Described bio-sensing tester comprises first operational amplifier, second operational amplifier, first reference voltage source, second reference voltage source, detection means, and first port, second port, the 3rd port, the 4th port; First input of described first operational amplifier connects described first reference voltage source, and second input connects described second port, and the output of described first operational amplifier connects described first port, and connects described detection means; First input of described second operational amplifier connects described second reference voltage source, and second input connects described the 4th port, and the output of described second operational amplifier connects described the 3rd port; During use, first port and the coupling of described first conductive channel, second port and the coupling of described second conductive channel, the 3rd port and the coupling of described the 3rd conductive channel, the 4th port and the coupling of described the 4th conductive channel.
In a kind of embodiment of described bio-sensing test macro, described bio-sensing tester also comprises resistance, and described resistance is connected between the output and described first port of described first operational amplifier.
In a kind of embodiment of described bio-sensing test macro, the resistance of described resistance is more than 10 times of dead resistance of described bio-sensing test-strips.
In a kind of embodiment of described bio-sensing test macro, described first reference voltage source and second reference voltage source are digital to analog converter; Described detection means is analog to digital converter.
When carrying out the bio-sensing test, biological reagent and biological analyte reaction generate little electric current, but because operational amplifier has very large input impedance, and little electric current can only flow to or flow out the output of first operational amplifier, namely flow in first conductive channel; There is not electric current to flow and connect on second conductive channel of first operational amplifier second input, that is to say, current potential unanimity on second conductive channel, first test electrode is identical with the current potential of second input of first operational amplifier, the current potential of first test electrode can be set accurately by digital to analog converter D/A334, guarantee that the actual voltage difference that is applied on the bio-sensing test-strips is required voltage difference, make the current potential that the test electrode of bio-sensing test-strips obtains setting, guaranteed the precision of bio-sensing test.
Further, by resistance in series between first conductive channel of the output of first operational amplifier and bio-sensing test-strips, because resistance in series is far longer than dead resistance usually, for example, in described a kind of embodiment, resistance in series is set to be at least more than 10 times of dead resistance, thereby the pressure drop that forms on the dead resistance will significantly reduce, pressure drop will mainly focus on resistance in series, like this during the electric signal of the output detection of biological sensing by first operational amplifier, the influence to electrical signal detection of dead resistance will reduce greatly, thereby reduce the influence of dead resistance to measuring accuracy, further improve the bio-sensing measuring accuracy.
Embodiment
By reference to the accompanying drawings the present invention is described in further detail below by embodiment.
The present invention relates to a kind of bio-sensing tester and bio-sensing test macro.Described bio-sensing tester and bio-sensing test macro are used for test and biological fluid content of analyte---such as the relevant signal of blood-sugar content, also can be used for measuring and disturbing---such as the signal of hematocrit in the blood sugar and temperature correlation, in order to analyze the content of analyte signal.This bio-sensing tester and bio-sensing test macro that the embodiment of the invention proposes, (it is poor to be generally constant potential with required potential difference (PD) for energy, but it is poor to be not limited to constant potential) be applied to the test electrode of reaction zone, and compensate the dead resistance of bio-sensing test-strips conductive channel simultaneously, thereby reduce the dead resistance of bio-sensing test-strips as much as possible to the influence of measuring accuracy.
Referring to Fig. 2, employed bio-sensing test-strips comprises in the embodiment of the invention: substrate 12 generally can be the thick film of 350uM, as PET or PVC etc.; Working electrode 226,214 reaches electrode 216,224, can be made by technologies such as printing or plating; Wherein, label 226 is as the general designation of label 226a, 226b, 226c; Label 214 is as the general designation of label 214a, 214b, 214c; Label 216 is as the general designation of label 216a, 216b, 216c; Label 224 is as the general designation of label 224a, 224b, 224c.The implication of label a, b, c is as follows:
Test electrode a---the electrode part in the reaction zone: 226a, 214a, 216a, 224a;
Contact terminal b---the part that is connected with the bio-sensing tester: 226b, 214b, 216b, 224b;
Bus c---connect the part of test electrode and contact terminal: 226c, 214c, 216c, 224c;
The bca of above-mentioned each electrode or acb constitute each conductive channel of bio-sensing test-strips, wherein, 226b, 226c, 226a constitute first conductive channel, 214b, 214c, 214a constitute second conductive channel, 216b, 216c, 216a constitute the 3rd conductive channel, and 224b, 224c, 224a constitute the 4th conductive channel.The first test electrode 226a, 214a are communicated with first conductive channel, second conductive channel; The second test electrode 216a, 224a are communicated with the 3rd conductive channel, the 4th conductive channel.
Biological reagent 18 is attached to test electrode 216a, the 214a of bio-sensing test-strips one end by printing or spraying, technologies such as some liquid etc.When adding a potential difference (PD) for test electrode 216a, 214a, biological reagent 18 reacts with the biological analyte of required mensuration content, can measure the content of described biological analyte reaction.
The bio-sensing test-strips has a reaction zone 20.Reaction zone 20 comprises test electrode 214a, 216a, and test electrode directly contacts with the sample of the biological analyte of required mensuration content.In whole electro-chemical test system, the bio-sensing test-strips is inserted in the tester that uses this test-strips, test electrode 214a, 216a in the reaction zone 20 and Fig. 3 or bio-sensing tester shown in Figure 4 are connected, the bio-sensing tester provides a potential difference (PD) for test electrode 214a, 216a, and (it is poor to be generally constant potential, but it is poor to be not limited to constant potential), and measure electrochemical sensor to the reaction of this potential difference (PD).This reaction and content of analyte are proportional.
The bio-sensing test-strips has contact region 22.Contact region 22 comprises contact terminal 226b, 214b, 216b, 224b.Contact region 22 usually but may not be certain, be positioned at away from the end on the bio-sensing test-strips of reaction zone 20.
The bio-sensing tester connects the bio-sensing test-strips by contact terminal 226b, 214b, 216b, 224b.Bus 226c, 214c, 216c, 224c connect contact terminal 226b, 214b, 216b, 224b and test electrode 226a, 214a, 216a, 224a respectively.
Fig. 3 is the circuit diagram of the bio-sensing tester of embodiment one, test electrode 214a, the 216a that the test circuit of bio-sensing tester comprises for the reaction zone 20 of bio-sensing test-strips applies required potential difference (PD), and (it is poor to be generally constant potential, but it is poor to be not limited to constant potential), and compensate the dead resistance of the conductive channel of bio-sensing test-strips simultaneously, thereby reduce dead resistance as much as possible to the influence of measuring accuracy.
When the bio-sensing test-strips is inserted the bio-sensing tester, first port of bio-sensing tester is connected to the contact terminal 226b of bio-sensing test-strips, second port is connected to the contact terminal 214b of bio-sensing test-strips, the 3rd port is connected to the contact terminal 216b of bio-sensing test-strips, and the 4th port is connected to the contact terminal 224b of bio-sensing test-strips.
Second operational amplifier 320 of the test circuit of bio-sensing tester is formed voltage follower with electrode 216,224.First input of second operational amplifier 320 connects second reference voltage source (in the example of Fig. 3, be digital to analog converter D/A336), second input connects the 4th port that is used for connecting bio-sensing test-strips contact terminal 224b, and output connects the 3rd port that is used for connecting bio-sensing test-strips contact terminal 216b.Second reference voltage source, i.e. D/A336 output required voltage is supplied with described voltage follower, thus the test electrode 216a that follows path that is positioned at voltage follower keeps exporting same voltage with D/A522.
First input of first operational amplifier 310 of the test circuit of bio-sensing tester connects first reference voltage source (in the example of Fig. 3, be digital to analog converter D/A334), second input of first operational amplifier 310 connects second port that is used for connecting bio-sensing test-strips contact terminal 214b, and the output of first operational amplifier 310 connects first port that is used for connecting bio-sensing test-strips contact terminal 226b.In the inside of tester circuit, the output of first operational amplifier 310 is also connected to a detection means (in the example of Fig. 3, namely modulus converter A/D 332).D/A334 output required voltage is supplied with first input of first operational amplifier 310, and the current potential of second input of first operational amplifier 310 equates with the current potential of its first input.The biological reagent of reaction zone 20 and biological analyte reaction, generate little electric current, but because operational amplifier has very large input impedance, little electric current can only flow to or flow out the output of first operational amplifier 310, and namely first conductive channel that constitutes at 226b, 226c, 226a flows; There is not electric current to flow and connect on 214a, the 214c of first operational amplifier 310 second input, second conductive channel that 214b constitutes, that is to say, current potential unanimity on 214a, 214c, the 214b conductive channel, namely test electrode 214a is identical with the current potential of second input of first operational amplifier 310.Test electrode 226a is identical with the current potential of first input of first operational amplifier 310, is the current potential that digital to analog converter D/A334 exports, and the current potential of test electrode 214a is the current potential of electrode 226a, can set by digital to analog converter D/A334.
Therefore can pass through digital to analog converter D/A334,336 between test electrode 214a, the 216a and set required potential difference (PD).The setting of potential difference (PD), test result are come out mainly by microprocessor processes, microprocessor has first control output end that links to each other with first reference voltage source (digital to analog converter D/A334) and second control output end that links to each other with second reference voltage source (digital to analog converter D/A336), sets in order to the output potential of controlling first reference voltage source and second reference voltage source; Microprocessor also has the input end that links to each other with detection means (modulus converter A/D 332); Digital to analog converter D/A334,336, digital to analog converter D/A336 etc. all can be arranged on the inside of microprocessor, namely first reference voltage source and second reference voltage source are the digital to analog converter of microprocessor internal, and detection means is the analog to digital converter of microprocessor internal.
There are dead resistance in conductive channel 226b, 226c, 226a, and because technological reason, this dead resistance of bio-sensing test-strips can not be accomplished unanimity.Referring to Fig. 4, can be between the output of first operational amplifier of bio-sensing tester and first port resistance in series 440, and make the resistance of this resistance in series 440 much larger than the dead resistance of (for example more than 10 times) conductive channel 226b, 226c, 226a, the pressure drop that to be little electric current produce at resistance 440 is much larger than the pressure drop that produces in dead resistance, thereby can control the measuring error that dead resistance is brought.
Above content be in conjunction with concrete embodiment to further describing that the present invention does, can not assert that concrete enforcement of the present invention is confined to these explanations.For the general technical staff of the technical field of the invention, without departing from the inventive concept of the premise, can also make some simple deduction or replace, all should be considered as belonging to protection scope of the present invention.