Synthesis of 2-(2-Hydroxy-4-Methoxybenzylideneamino)-4, 5, 6, 7-Tetrahydrobenzo[b] Thiophene-3-Carboxamide and Application of This New Sensor for Determination of Fluoride in Toothpaste by Spectrofluorometric Methods

Document Type : Research Article

Authors

1 Department of Chemistry, Faculty of Science, Payam Noor University, P.O. Box 3697-19395 Tehran, I.R. IRAN

2 Department of Chemistry, Faculty of Science, Ilam University, Ilam, I.R. IRAN

Abstract

In this work, we synthesized a new thiophene derivative Schiff base as new luminophore. The aim of this study was determination of fluoride using 2-[(E)-(2-Hydroxy-4-methoxybenzylidene) amino] -4, 5, 6, 7- tetrahydro-1-benzothiophene-3-carboxamide [Ligand L] as new and intense fluorescence sensor by spectrofluorometric method. In this method, we optimized all reagents concentrations such as ionic, pH, luminophore concentration. Afterwards, we used a new fluorimetric method for determination of fluoride ion based on quenching effect of fluoride ion on fluorescence of thiophene derivative schiff base, as new luminophore. Despite previous methods, that had less selectivity and sensitivity, in this work we presented a new sensitive fluorimetric sensor for determination of fluoride with good selectivity, sensitivity and reproducibility. A linear calibration range was obtained from 4.31×10-6 – 4.70×10-4. The relative standard deviation was very good (1.098% for 10-4 M of F- and n=5) and the detection limit was acquired 2.1×10-6 M. In addition, interference of some anions and cations were investigated. The proposed method was successfully applied for the determination of fluoride in toothpaste samples.

Keywords

Main Subjects


[1] Amanlou M., Hosseinpour M., Azizian H., Khoshayand M.R., Navabpoor M., Souri E., Determination of Fluoride in the Bottled Drinking Waters in Iran, Iranian Journal of Pharmaceutical Research (IJPR), 9(1): 37-42 (2009).
[2] Peckham S, Awofeso, N. Water Fluoridation: A Critical Review of the Physiological Effects of Ingested Fluoride as a Public Health Intervention, The Scientific World Journal, 10 (2014).
[3] حسن پهلوان زاده، حمید رضا زارع نژاد اشکذری، فلوراید زدایی از آب آشامیدنی با ستون جذب بستر ثابت با استفاده از جاذب ارزان قیمت بوکسیت، نشریه شیمی و مهندسی شیمی ایران، (2) 31: 17 تا 24 (1392).
[4] Bentley E.M., Ellwood R.P., Davies R.M., Oral Hygiene: Fluoride Ingestion from Toothpaste by Young Children, Br Dent J., 186(9): 460-2 (1999).
[5] Freire I.R., Pessan J.P., Amaral J.G., Martinhon C.C.R., Cunha R.F., Delbem A.C.B., Anticaries Effect of Low-Fluoride Dentifrices with Phosphates in Children: A Randomized, Controlled Trial, Journal of Dentistry, 50; 37-42 (2016).
[7] Sebastian S.T., Siddanna S., Total and Free Fluoride Concentration in Various Brands of Toothpaste Marketed in India, Journal of Clinical and Diagnostic Research (JCDR), 9(10): ZC09-ZC12 (2015).
[8] Gomez-Hens A., Valcarcel M., Spectrofluorimetric Determination of Inorganic Anions: A Review, Analyst., 107(1274): 465-94 (1982).
[9] Yahyavi H., Kaykhaii, M., Mirmoghaddam M., Recent Developments in Methods of Analysis for Fluoride Determination, Critical Reviews in Analytical Chemistry, 46(2):106-21 (2016).
[11] Švarc-Gajić J., Stojanović Z., Vasiljević I., Kecojević I., Determination of Fluorides in Pharmaceutical Products for Oral Hygiene, Journal of Food and Drug. Analysis, 21(4): 384-9 (2013).
[12] Yang X-F., Qi H., Wang L., Su Z., Wang G., A ratiometric Fluorescent Probe for Fluoride Ion Employing the Excited-State Intramolecular Proton Transfer, Talanta, 80(1): 92-7 (2009).
[13] Qiu B., Zeng Y., Cao L., Hu R., Zhang X., Yu T., Chen J., Yang G., Li Y., A Colorimetric and Ratiometric Fluorescence Sensor for Sensitive Detection of Fluoride Ions in Water and Toothpaste, RSC Advances, 6(54): 49158-63 (2016).
[14] Li Y., Duan Y., Zheng J., Li J., Zhao W., Yang S., Yang R., Self-Assembly of Graphene Oxide with a Silyl-Appended Spiropyran Dye for Rapid and Sensitive Colorimetric Detection of Fluoride Ions, Analytical Chemistry, 85(23): 11456-63 (2013).
[15] Xiong Y., Wang C., Tao T., Duan M., Tan J., Wu J., et al., Fabrication of a Miniaturized Capillary Waveguide Integrated Fiber-Optic Sensor for Fluoride Determination, Analyst, 141(10): 3041-9 (2016).
[19] Zaher Barghouthi S.A., Spectrophotometric Determination of Fluoride in Groundwater Using Resorcin Blue Complexes, American Journal of Analytical Chemistry, 3(9): 651-655 (2012).
[22] Marco V., Carrillo F., Pérez-Conde C., Cámara C., Kinetic Flow-Injection Spectrofluorimetric Method for the Determination of Fluoride, Analytica Chimica Acta., 283(1): 489-93 (1993).
[23] Anand T., Sivaraman G., Iniya M., Siva A., Chellappa D., Aminobenzohydrazide Based Colorimetric and ‘Turn-on’ Fluorescence Chemosensor for Selective Recognition of Fluoride, Analytica Chimica Acta., 876: 1-8 (2015).
[24] Cury J.A. MG, Buzalaf M.A.R., Akman S., Men Y., Rigalli A., Ahmed I., Brahman K.D., Welz B., Fluorine : Chemistry, Analysis, Function and Effects. In: Preedy VR, editor. "Fluorine: Chemistry, Analysis, Function and Effects." Cambridge, United Kingdom: Royal Society of Chemistry; p. (2015).
[25] Huang W., Li J., Tang J., Liu H., Shen J., Jiang H., Microwave‐Assisted Synthesis of 2‐Amino‐thiophene‐3‐Carboxylic Derivatives Under Solvent‐Free Conditions, Synthetic Communications, 35(10): 1351-7 (2005).
[26] Lee D.H., Im J.H., Lee J.-H., Hong J.-I., A New Fluorescent Fluoride Chemosensor Based on Cnformational Restriction of a Biaryl Fluorophore, Tetrahedron Letters, 43(52): 9637-40 (2002).
[27] Lee K.H., Lee H-Y., Lee D.H., Hong J-I., Fluoride-Selective Chromogenic Sensors Based on Azophenol, Tetrahedron Letters, 42(32): 5447-9 (2001).
[28] Hu R., Feng J., Hu D., Wang S., Li S., Li Y., Yang G., A Rapid Aqueous Fluoride Ion Sensor with Dual Output Modes, Angewandte Chemie International Edition, 49(29): 4915-8 (2010).
[29] Bamesberger A., Schwartz C., Song Q., Han W., Wang Z., Cao H., Rational Design of a Rapid Fluorescent Approach for Detection of Inorganic Fluoride in MeCN-H2O: a New Fluorescence Switch Based on N-aryl-1,8-Naphthalimide, New Journal of Chemistry, 38(3): 884-8 (2014).