Cholesterol Measurement System Based On Color Detection

Nowadays,cardiovascular diseases are the most prevalent diseases in terms of morbidity and mortality,posing a serious threat to human health.Numerous medical studies have shown that the occurrence of cardiovascular diseases is closely related to high serum cholesterol levels.Therefore,accurate measurement of cholesterol can help provide a basis for the diagnosis of cardiovascular diseases and is important for the prevention and control of such diseases.In this paper,a portable cholesterol measurement system based on fluorescence color detection is designed.The system combines the high sensitivity of fluorescence measurement with the convenience of color sensing,and converts the change of fluorescence intensity into the change of color.It can achieve accurate and rapid determination of low concentration cholesterol.In this study,gold nanoclusters with blue-green fluorescence were synthesized by a one-pot method based on the fluorescence method with HAu Cl₄ as the raw material and sulfhydryl-β-cyclodextrin as the reducing and protecting agent.The cavity of sulfhydryl-β-cyclodextrin is used as a selective unit and the gold nucleus acts a reporting unit that recognizes cholesterol through host-guest interactions.The inclusion complex formed by the two causes changes in the structural rigidity of the gold nanoclusters resulting in enhanced fluorescence,and the process enables non-enzymatic determination of low levels of cholesterol without any additional fluorescent dyes or quenching agents.The probe reacts linearly with cholesterol in the concentration range of 15.0-150.0μmol/L.Based on this,the system detects the color before and after fluorescence enhancement through RGB color sensor TCS230,and thus enables the determination of cholesterol levels.The overall design of the system is as follows:the CD-Au NCs solution is placed in a dark room as the detection unit,and the RGB color sensor TCS230 is used to detect the color of the light emitted from the gold nanoclusters before and after adding different concentrations of cholesterol solution,and the measured color is converted from RGB color space to HSV color space which is more in line with the characteristics of human visual perception.According to the experiment,the measured value of Hue has a good linear relationship with cholesterol concentration,which enables the determination of the cholesterol concentration and thus the construction of a convenient cholesterol detection system with high accuracy and high integration.The system includes optical system module,color sensor module,microprocessor module,power supply module,program download module,human-computer interaction module and and 3D printing detection darkroom module.The system is powered by lithium battery,and uses STM32F407 chip as microcontroller.The orthogonal optical paths are used in optical systems to effectively reduce the interference of excitation light,and the isolated color sensor make the optical path structure more compact.The overall structure of the system is designed by Solid Works software The interface development tool little VGL is used to complete the design of the human-computer interaction module,which makes the graphical interface more beautiful.The experiment shows that the portable cholesterol measurement system based on color detection designed in this project is simple to operate,highly integrated,and has good results in reproducibility experiments and stability tests.With the cholesterol concentration as the abscissa and the Hue value as the ordinate,the standard curve is established:H=-0.0971C+249.19,R²=0.97,and the detection limit is 16.07μmol/L.It has a good linearity and can be used for the determination of low concentration cholesterol.