Raman Spectroscopy Literature Review

Water is a precious commodity and water quality can easily affect human health, thus, it is important to improve the methods and technologies for water quality monitoring. The need for immediate and early warning of a contamination, in water from the tap or the environment, is necessary because even very small amounts of pathogens can be dangerous for people. WaterMon aims to address these challenges and has conducted a literature review of the methods to detect pathogens.

Pathogens are the biggest challenge to identify and quantify in a water sample. Several techniques exist for the detection of pathogens, in general the bacteria will be tagged with a special marker. This marker can be antibody-or aptamer-based.

Raman Spectroscopy shows promising results in detecting quantity of pathogens. Several studies also shows different methods to enhance the detection accuracy[1]. The detecting accuracy also varied with the sample temperature and the incubation time[2]. One study[3] using an electric field to capture the batteries in the focus of the Raman Spectroscopy or other researcher[4] using a micro electrode and the help of electroosmosis and dielectrophoresis to concentrate the bacteria.

Colorimetric detection is uses the marker to color the sample. Another study[5] achieved a detecting time of only 2 hours with this method, which is shorter than incubation based methods. Using electrochemical impedance spectroscopy (EIS) with an aptasensor for the detection of bacteria, researchers measured the impedance to evaluate the type and quantity of the bacteria, which shows good results but required specific cleaning procedure for repeatable usage of the sensor[6].

 

 

Bibliography

[1]         Y. Zhang, S. Zhao, J. Zheng, and L. He, “Surface-enhanced Raman spectroscopy (SERS) combined techniques for high-performance detection and characterization,” TrAC – Trends Anal. Chem., vol. 90, pp. 1–13, 2017.

[2]         D. Yang, H. Zhou, C. Haisch, R. Niessner, and Y. Ying, “Reproducible E. coli detection based on label-free SERS and mapping,” Talanta, vol. 146, pp. 457–463, 2016.

[3]         M. Yanagisawa, M. Saito, M. Kunimoto, and T. Homma, “Transmission-type plasmonic sensor for surface-enhanced Raman spectroscopy,” Appl. Phys. Express, vol. 9, no. 12, 2016.

[4]         D. S. Liao, J. Raveendran, S. Golchi, and A. Docoslis, “Fast and sensitive detection of bacteria from a water droplet by means of electric field effects and micro-Raman spectroscopy,” Sens. Bio-Sensing Res., vol. 6, pp. 59–66, 2015.

[5]         W. Ren, W. Liu, and J. Irudayaraj, “A net fishing enrichment strategy for colorimetric detection of E. coli O157:H7,” Sensors Actuators, B Chem., vol. 247, pp. 923–929, 2017.

 

[6]         S. Brosel-Oliu, R. Ferreira, N. Uria, N. Abramova, R. Gargallo, F. X. Muñoz-Pascual, and A. Bratov, “Novel impedimetric aptasensor for label-free detection of Escherichia coli O157:H7,” Sensors Actuators, B Chem., vol. 255, pp. 2988–2995, 2018.