COMMENT ON THE PAPER "WATER-SOLUBLE PYRIDINE-BASED COLORIMETRIC CHEMOSENSOR FOR NAKED EYE DETECTION OF SILVER IONS: DESIGN, SYNTHESIS, SPECTRAL AND THEORETICAL INVESTIGATION", ANAL. METHODS 2014, 6, 9610-9614 BY B. ANNARAJ AND M. A. NEELAKANTAN

The Schiff base derived from pyridoxal and 2-aminoethanol was previously reported (Anal. Methods 2014, 6, 9610-9614) to be used as a colorimetric and fluorescent chemosensor for Ag+ ions in an aqueous solution. We show that this Schiff base undergoes fast hydrolysis in an aqueous solution. We also report on the failure to reproduce the results of the above-mentioned paper related to the discovery of silver(I) ions in an aqueous solution using Schiff base of pyridoxal and 2-ami-noethanol as chemosensor. The present comment has been initially submitted to the Analytical Methods journal, Royal Chemical Society, which published the criticized paper in 2014. Later, we received a decision letter about rejection of our critical comment, which was justified by the opinion that our manuscript contains neither novel information nor new interpretation of the results pub-lished previously by the Analytical Methods journal. Instead, we just raise concerns in relation to the previously published data. The Editorial Office of the Analytical Methods journal informed us about the intention to contact the authors of the criticized paper and retract the latter if authors would have been unable to refute the raised concerns. We would like to note that the criticized paper is not still denoted as questionable and is still available on the journal page. We believe that the results obtained during working on this comment are of interest to the broad scientific audience. We appreciate the possibility to initiate the scientific discussion on the pages of the ChemChemTech (Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.) journal, and would appreciate if authors of the paper (Anal. Methods 2014, 6, 9610-9614) would join it.