title: An iPhone-based digital image colorimeter for detecting tetracycline in milk.
abstract: An iPhone-based digital image colorimeter (DIC) was fabricated as a portable tool for monitoring tetracycline (TC) in bovine milk. An application named ColorConc was developed for the iPhone that utilizes an image matching algorithm to determine the TC concentration in a solution. The color values; red (R), green (G), blue (B), hue (H), saturation (S), brightness (V), and gray (Gr) were measured from each pictures of the TC standard solutions. TC solution extracted from milk samples using solid phase extraction (SPE) was captured and the concentration was predicted by comparing color values with those collected in a database. The amount of TC could be determined in the concentration range of 0.5-10 μg mL(-1). The proposed DIC-iPhone is able to provide a limit of detection (LOD) of 0.5 μg mL(-1) and limit of quantitation (LOQ) of 1.5 μg mL(-1). The enrichment factor was 70 and color of the extracted milk sample was a strong yellow solution after SPE. Therefore, the SPE-DIC-iPhone could be used for the assay of TC residues in milk at the concentration lower than LOD and LOQ of the proposed technique.
authors: Department of Chemistry, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand. Electronic address: prinyam@nu.ac.th.
authors: Prinya
authors: P
authors: Masawat
authors: Department of Computer Science and Information Technology, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand.
authors: Antony
authors: A
authors: Harfield
authors: Department of Chemistry, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand.
authors: Anan
authors: A
authors: Namwong
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D002417:Cattle; D040421:Cell Phone; D003124:Colorimetry / Q000379:methods*; D057230:Limit of Detection; D008892:Milk / Q000737:chemistry*; D052616:Solid Phase Extraction / Q000379:methods; D013752:Tetracycline / Q000032:analysis*
chemical_list: D000900:Anti-Bacterial Agents; D013752:Tetracycline
keywords: Digital image colorimeter; Milk; Portable; Tetracycline; iPhone