Measuring chloride in serum using single programmable system on chip (PSoC)

PSoC devices are dynamically reconfigurable, versatile programming, low-power consumption and multiple interfacing, which motivates the design of portable and inexpensive instruments. The chloride analyzer is built around a cypress CY8C27443 PSoC with its analog and digital blocks, which is typically an embedded system, and it is configured for the measurement of chloride in serum. The principle of chloride measurement is based on colorimetry with LED as illuminating source and photodiode GASPG1104 as a light sensor. The run to run precision of the implemented system is determined by analysing human control serum Accutrol™ Normal (Sigma) and the chloride concentration is found to be 104 ± 4 mmol/l (mean ± SD, n = 5), which is close to the certified value. This system has been used successfully for the routine assay of bio-medical samples, with the results in good agreement with values obtained by the commercial clinical analyzer at 95% of confidence level.