Utilization of Android-base Smartphone to Support Handmade Spectrophotometer : A Preliminary Study

12th Joint Conference on Chemistry

Ujiningtyas, R.^1 ; Apriliani, E.^1 ; Yohana, I.^1 ; Afrillianti, L.^1 ; Hikmah, N.^2 ; Kurniawan, C.^1

Chemistry Departement of Semarang, State University, Indonesia^1

Computer Science Departement of Semarang, State University, Indonesia^2

关键词: Absorbances;    Calibration curves;    Chemical species;    Color composition;    Communication technologies;    LEd lamps;    Spectrophone;    Visible spectrophotometers;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/349/1/012055/pdf
DOI  :  10.1088/1757-899X/349/1/012055

来源: IOP

【 摘 要 】

Visible spectrophotometer is a powerful instrument in chemistry. We can identify the chemical species base on their specific color and then we can also determine the amount of the species using the spectrophotometer. However, the availability of visible spectrophotometer still limited, particularly for education. This affect the skill of student to have experience on handling the instrumentation. On the other hand, the communication technology creates an opportunity for student to explore their smart feature, mainly the camera. The objective of this research is to make an application that utilize the camera feature as a detector for handmade visible spectrophotometer. The software have been made based on android program, and we name it as Spectrophone®. The spectrophotometer consists of an acrylic body, sample compartment, and light sources (USB-LED lamp powered by 6600 mAh battery). Before reach the sample, the light source was filtered using colored-mica plastic. The spectrophone® apps utilize the camera to detect the color based on its RGB composition. A different colored solution will show a different RGB composition based on the concentration and specific absorbance wavelength. We then can choose one type of color composition, R or G or B only to be converted as an absorbance using -Log (Cs/Co), where Cs and Co are color composition of sample and blank, respectively. The calibration curve of metilen blue measured. In a red (R) composition, the regression is not linear (R2=0.78) compare to the result of UV-Vis spectrophotomer model Spectroquant Pharo 300 (R2=0.8053). This measurement result shows that The Spectrophone® still need to be evaluated and corrected. One problem than can we identify that the diameter of pick point of RGB composition is too wide and this will affect the reading color composition. Next, we will fix the problem and in advance we will apply this Spectrophone® in a wide scale.