RESUMO
A new micro embedded telemetry system was developed for the amperometric sensing detection. Its output voltage range was ±0. 5 V and resolution was<1 mV. The current acquisition range was ±1μA and the minimum resolution was 0. 2 nA. This telemetry system was designed based on microprocessor ADuCM360, including a potentiostat, a current detection module and a radio module. And the size was only 24 mm × 13 mm × 11 mm. The computer software written in LabVIEW language was used for data storage and display. In order to verify the accuracy and reliability of this system, an electrical performance test was performed. The current response for ascorbic acid with different concentration was recorded by using the telemetry system. The potential of working electrode was set as 30 mV, and the current response of ascorbic acid electrode had a good linear relationship with its concentration within the concentration range of 50-300 μmol/L. Linear equation was I(nA) = 2. 98CAA(μmol/L)-137. 39, and linear correlation coefficient R2=0. 984. Moreover, the applicability of the instrument in the study for living animals was explored by using the cerebral ischemia as model.
RESUMO
A new embedded telemetry system for potentiometric sensors was developed. The system consisted of a transmitter unit, a receiver unit and a personal computer ( PC) . The transmitter unit included a current amplifier, a∑-Δanalog-to-digital converter ( ADC) , a microcontroller unit ( MCU) and a radio module. The receiver unit was composed of a radio module, a microcontroller unit and a serial-to-USB converter module. The receiver unit was connected to an upper computer via a universal serial bus ( USB ) . The embedded software written in C language controlled the signal acquisition and transmission. The computer software written in LabVIEW language was used for data storage and display. The range of the acquisition voltages was from-1. 17 V to +1. 17 V. In order to verify the accuracy and reliability of this system, a control experiment had been done with this system and a digital multimeter. Moreover, a response test of acidity changes had been done with the self-made H+ selective electrode. The results showed that the accuracy of this system could be up to 0. 1 mV and it had strong anti-noise ability. The square of the linear correlation coefficient of the response of the changes in pH values was 0 . 998 . The curve of the results measured by this system was consistent with that measured by the commercial electrochemical analyzer. The system was built with standard hardware components and the size of the transmitter unit was only 29 mm×14 mm×11 mm. It can be easily used for remote and real-time detection for the potentiometric sensor.