Related Experiment Video
Updated: Jul 26, 2026

Electronic Tongue Generating Continuous Recognition Patterns for Protein Analysis
Published on: September 16, 2014
Smart-detection approach for protein residues to evaluate the cleaning efficacy of reusable medical devices
T Ouirungroj1, S Apichai2, T Pattananandecha2
1Department of Pharmaceutical Sciences, Faculty of Pharmacy, Chiang Mai University, Chiang Mai, Thailand; Center of Excellence for Innovation in Analytical Science and Technology for Biodiversity-Based Economic and Society (I-ANALY-S-T_B.BES-CMU), Chiang Mai University, Chiang Mai, Thailand.
Background:
Healthcare-associated infections are challenging problems to eradicate. In practice, infection prevention and control regarding the effective cleaning of reusable medical devices is performed. However, real-time monitoring of potentially contaminated devices is hindered by the complex, costly investigations and the time required.
Aim:
To develop an inexpensive approach providing high-sensitivity, rapid, and low-cost protein residue determination on medical devices.
Methods:
Colourimetric reactions for protein were modified and downscaled to produce a colour product on the moving drop platform and to operate combined with our custom-built smartphone application in order to evaluate and save protein contamination data. The intensity of a product colour was detected by photographing with a smartphone camera and was proportional to the protein concentration in the linear range of 5-20 μg/mL. The protein content was processed on a custom-built smartphone application, namely PromoveCheck.
Findings:
The proposed procedure was highly sensitive, yielding limits of detection and limits of quantification, at 0.03 and 0.10 μg based on the Bradford reaction. It was applied to reusable medical devices, showing no significant differences from the spectrophotometric method and a correlation with the o-phthaldialdehyde method (P<0.05).
Conclusion:
This approach demonstrates low cost, sensitivity, efficiency and traceability for investigating reusable medical device cleanliness. The PromoveCheck app can report and acquire protein content that can be used for traceability and alerts concerning questionable or discovered contaminant devices, improving the quality management of the Central Sterile Supply Department.

