Novel Semi-Automated Design for Determination of Iron in Water using Smartphone Camera Complementary Metal-Oxide-Semiconductor (CMOS) Biosensor as a Detector Device

Abstract

In this research, a new method was used to determine the amount of iron in water, by using the colour biosensor of the smart-phone device as a biosensor for the chromatic intensity of the samples images that are examined through a program (colour meter) downloaded to the phone. The concentration of the samples is measured from the value of the basic colours (red, green, blue) (RGB) for recorded video from a device (Galaxy J7 prime 2). An accessory for the mobile device is designed from plastic (black acrylic). In the form of a dark box from the inside equipped with a flow cell and a mirror reflecting the flash light emitted by the mobile device and a green filter complementing the red colour, and a micro switch connected to a smart-phone device via earphones, and the device is attached to the accessory by the device case. The calibration curve for this method was in the range of mg/L (1-8), the correlation coefficient (R2 ) was equal to (0.999), the limit of detection was in the amount of (0.2) mg/L, and the relative standard deviation (RSD%) for the concentration was (4) mg/L, for which the examination was repeated (10) times, and its value was (0.6 %), and the recovery value (Recovery%) was equal to (101.5 %).