Highly sensitive determination of poly(hexamethylene guanidine) by Rayleigh scattering using aggregation of silver nanoparticles

• Published in: Mikrochimica acta (1966) Vol. 182; no. 5-6; pp. 965 - 973
• Main Authors: Artemyeva, Anastasia A., Samarina, Tatyana O., Sharov, Andrei V., Abramchuk, Sergei S., Ovcharenko, Еlena О., Dityuk, Alexander I., Efimov, Konstantin M., Beklemishev, Mikhail K.
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.04.2015; Springer
• Subjects: Agglomeration; Analytical Chemistry; Aqueous solutions; Calibration; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Guanidines; Humic acid; Hydrochlorides; Microengineering; Nanochemistry; Nanoparticles; Nanotechnology; Original Paper; Polyelectrolytes; Rayleigh scattering; Silver; Poly(hexamethylene guanidine); Rayleigh scattering; Silver nanoparticles; Determination of polyelectrolytes
• ISSN: 0026-3672; 1436-5073
• DOI: 10.1007/s00604-014-1411-6

We have found that low concentrations of the polycationic disinfectant poly(hexamethylene guanidine) hydrochloride (PHMG) induce the aggregation of citrate-stabilized silver nanoparticles (AgNPs) in aqueous solution. Based on this finding, we have worked out a method to the determination of PHMG. The protocol includes the steps of (a) centrifuging the water sample, (b) addition of an aliquot of the colloidal solution of the AgNPs, and (c) measurement of the intensity of scattered light. The method is surprisingly selective in that comparable concentrations of surfactants, humic acids and protein do not interfere. Besides, an up to 50 mM concentration NaCl, and up to 5 mM of Mg(II) or Ca(II) are tolerated. Other cationic polyelectrolytes, polyethyleneimine and poly(dimethyldiallyammonium chloride), also cause aggregation of AgNPs but to a lesser extent. The determination of PHMG was  performed in spiked samples (run-off, tap and swimming pool waters) with detection limits of 2·10 −8 , 4·10 −7 , and 6·10 −6  M (by monomer unit), respectively. The linear ranges are wider and the detection limits are lower than those of known spectrophotometric methods. It is necessary, however, to correct the calibration plot for background scattering by the sample and to establish a calibration plot for each kind of water sample. Notwithstanding this, the approach is attractive because it is sensitive, rapid, and simple. Graphical Abstract The polycationic disinfectant poly(hexamethylene guanidine) hydrochloride (PHMG) induces the aggregation of citrate-stabilized silver nanoparticles (AgNPs) in aqueous solution. Based on this finding, a method for the determination of ppb concentrations of PHMG by Rayleigh scattering method has been developed.