Yeni Sentezlenen Floresan Schiff Bazı Türevinin Fotokarakterizasyonu ve pH Algılama Özellikleri

Yıl 2025, Cilt: 15 Sayı: 3, 1119 - 1132, 15.09.2025

Merve Zurnacı

https://doi.org/10.31466/kfbd.1617959

Öz

pH sensörlerinin geliştirilmesinde, farklı, yüksek hassasiyet ve hızlı tepki floresan malzemelerin tasarımı ve sentezi çok önemlidir. Bu çalışmada, yeni sentezlenen fenantroimidazol içeren 1,3,4-tiyadiazol türevinin (PHT1) etanolde 3,5-ditertbütilsalisilaldehit (1:1) ile kondenzasyon reaksiyonu ile yeni bir pH-duyarlı Schiff bazı ligandı (PHS1) sentezlendi. Moleküler yapı, yapısal karakterizasyon yöntemleri ile doğrulandı. PHS1'in absorpsiyon ve floresan özellikleri, fotokarakterizasyon özelliklerini belirlemek için DMSO'da incelendi. Daha sonra, PHS1 floresan pH sensörü olarak araştırıldı. PHS1'in değişen pH'ta (pH=2,0, 4,0, 6,0, 8,0, 10,0 ve 12,0'da) UV absorpsiyon ve emisyon çalışmaları Britton-Robinson tamponunda belirlendi. pH 2,0'de 345 nm'de kaydedilen emilim dalga boyu, pH arttıkça batokromik etki gösterdi (pH= 4,0'da; 6,0 ve 8,0). pH 10,0 ve 12,0'de, PHS1 357 nm'de iki emilim tepe noktası ve 405 nm'de yeni bir düşük enerjili emilim bandı gösterdi. PHS1'in floresan spektrumu pH=2,0-12,0 arasında 439 nm’den 473 nm’ye artan bir dalga boyu ile kırmızıya kayma gösterdi. Bu sonuçlar PHS1'in asidik ve bazik ortamlardaki pH değişimine duyarlı olduğunu gösterdi.

Anahtar Kelimeler

Schiff Bazı Türevi , pH Sensörü , Fotokarakterizasyon , UV-Vis absorpsiyonu , Floresans

Etik Beyan

Yazar bu çalışmanın Araştırma ve Yayın Etiğine uygun olduğunu beyan eder.

Photocharacterization and pH Sensing Properties of a Novel Synthesized Fluorescent Schiff Base Derivative

Öz

Design and synthesis of different, highly sensitive and fast response fluorescent materials are very important in the development of pH sensors. In this study, a new pH-sensitive Schiff-base ligand (PHS1) was synthesized by the condensation reaction of newly synthesized 1,3,4-thiadiazole derivative containing phenanthroimidazole (PHT1) with 3,5-ditertbutylsalicylaldehyde (1:1) in ethanol. The molecular structure was confirmed by structural characterization methods. The absorption and fluorescence properties of PHS1 were investigated in DMSO to determine the photocharacterization properties. Then, PHS1 was investigated as a fluorescent pH sensor. UV absorption and emission studies of PHS1 with varying pH (at pH=2.0, 4.0, 6.0, 8.0, 10.0 and 12.0) were determined in Britton-Robinson buffer. The absorption wavelength recorded at 345 nm at pH 2.0 showed bathochromic effect as pH increased (at pH= 4.0; 6.0 and 8.0). At pH 10.0 and 12.0, PHS1 showed two absorption peaks at 357 nm and a new low energy absorption band at 405 nm. The fluorescence spectrum of PHS1 showed a red shift with an increasing wavelength from 439 nm to 473 nm between pH=2.0 and 12.0. These results showed that PHS1 is sensitive to pH change in acidic and basic environments.

Anahtar Kelimeler

Schiff Base Derivative , pH Sensor , Photocharacterization , UV-Vis absorption , Fluorescence

Etik Beyan

The author declares that this study complies with Research and Publication Ethics.

Kaynakça

• Alata, I., Broquier, M., Dedonder, C., Jouvet, C., & Marceca, E. (2012). Electronic excited states of protonated aromatic molecules: Protonated Fluorene. Chemical Physics, 393(1), 25–31. https://doi.org/10.1016/j.chemphys.2011.11.013
• Baldini, F. (1999, February 23). Critical review of pH sensing with optical fibres (R. A. Lieberman, ed.). https://doi.org/10.1117/12.339779
• Belko, N., Maltanava, H., Lugovski, A., Ferreira, R. A. S., Correia, S. F. H., Shabunya, P., … Samtsov, M. (2023). pH-Sensitive fluorescent sensor for Fe(III) and Cu(II) ions based on rhodamine B acylhydrazone: Sensing mechanism and bioimaging in living cells. Microchemical Journal, 191, 108744. https://doi.org/10.1016/j.microc.2023.108744
• Berhanu, A. L., Gaurav, Mohiuddin, I., Malik, A. K., Aulakh, J. S., Kumar, V., & Kim, K.-H. (2019). A review of the applications of Schiff bases as optical chemical sensors. TrAC Trends in Analytical Chemistry, 116, 74–91. https://doi.org/10.1016/j.trac.2019.04.025
• Bhardwaj, V., Ashok Kumar, S. K., & Sahoo, S. K. (2022). Fluorescent sensing (Cu2+ and pH) and visualization of latent fingerprints using an AIE-active naphthaldehyde-pyridoxal conjugated Schiff base. Microchemical Journal, 178, 107404. https://doi.org/10.1016/j.microc.2022.107404
• Brouwer, A. M. (2011). Standards for photoluminescence quantum yield measurements in solution (IUPAC technical report). Pure and Applied Chemistry, 83(12), 2213–2228. https://doi.org/10.1351/PAC-REP-10-09-31
• Grante, I., Actins, A., & Orola, L. (2014). Protonation effects on the UV/Vis absorption spectra of imatinib: A theoretical and experimental study. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 129, 326–332. https://doi.org/10.1016/j.saa.2014.03.059
• Halder, S., Bhattacharjee, A., Roy, A., Chatterjee, S., & Roy, P. (2016). Chromogenic and fluorescence sensing of pH with a Schiff-base molecule. RSC Adv., 6(45), 39118–39124. https://doi.org/10.1039/C6RA06284A
• Halder, S., Dey, S., & Roy, P. (2015). A quinoline based Schiff-base compound as pH sensor. RSC Advances, 5(68), 54873–54881. https://doi.org/10.1039/C5RA07538F
• Halder, S., Hazra, A., & Roy, P. (2018). Colorimetric and fluorescence sensing of pH with a Schiff-base molecule. Journal of Luminescence, 195, 326–333. https://doi.org/10.1016/j.jlumin.2017.11.055
• Huang, S., Ding, J., Bi, A., Yu, K., & Zeng, W. (2021). Insights into Optical Probes Based on Aggregation‐Induced Emission: from Restriction of Intramolecular Motions to Dark State. Advanced Optical Materials, 9(21). https://doi.org/10.1002/adom.202100832
• Hwang, S. M., Chae, J. B., & Kim, C. (2018). A Phenanthroimidazole-based Fluorescent Turn-Off Chemosensor for the Selective Detection of Cu2+ in Aqueous Media. Bulletin of the Korean Chemical Society, 39(8), 925–930. https://doi.org/10.1002/bkcs.11526
• Kaya, İ., Aydın, A., & Yıldırım, M. (2012). Synthesis and Spectrophotometric PH Sensing Applications of Poly-2-[4-(diethylaminophenyl)imino]-5-nitro-phenol and its Schiff Base Monomer for Two Different PH Ranges. Journal of Fluorescence, 22(1), 495–504. https://doi.org/10.1007/s10895-011-0983-3
• Khandogin, J., & Brooks, C. L. (2005). Constant pH Molecular Dynamics with Proton Tautomerism. Biophysical Journal, 89(1), 141–157. https://doi.org/10.1529/biophysj.105.061341
• Kumar, A., Virender, Saini, M., Mohan, B., Shayoraj, & Kamboj, M. (2022). Colorimetric and fluorescent Schiff base sensors for trace detection of pollutants and biologically significant cations: A review (2010–2021). Microchemical Journal, 181, 107798. https://doi.org/10.1016/j.microc.2022.107798
• Li, S.-S., Zhou, H.-T., Li, H.-Z., Zhong, L.-C., Zhang, F.-H., Sun, F.-B., … Zheng, Y.-C. (2024). Recent advances in the development of fluorescent sensors for sulfur mustard detection. Journal of Materials Chemistry C, 12(27), 9914–9928. https://doi.org/10.1039/D4TC01159G
• Ma, C., Xie, G., Zhang, X., Yang, L., Li, Y., Liu, H., … Wei, Y. (2017). Biocompatible fluorescent polymers from PEGylation of an aggregation-induced emission dye. Dyes and Pigments, 139, 672–680. https://doi.org/10.1016/j.dyepig.2016.12.070
• Maity, D., Halder, S., & Roy, P. (2018). High pH Sensing Properties of a New Schiff‐base Compound. ChemistrySelect, 3(2), 440–445. https://doi.org/10.1002/slct.201702307
• Mao, L., Liu, Y., Yang, S., Li, Y., Zhang, X., & Wei, Y. (2019). Recent advances and progress of fluorescent bio-/chemosensors based on aggregation-induced emission molecules. Dyes and Pigments, 162, 611–623. https://doi.org/10.1016/j.dyepig.2018.10.045
• Musikavanhu, B., Liang, Y., Xue, Z., Feng, L., & Zhao, L. (2023). Strategies for Improving Selectivity and Sensitivity of Schiff Base Fluorescent Chemosensors for Toxic and Heavy Metals. Molecules, 28(19), 6960. https://doi.org/10.3390/molecules28196960
• Namli, H., & Turhan, O. (2006). Background defining during the imine formation reaction in FT-IR liquid cell. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 64(1), 93–100. https://doi.org/10.1016/j.saa.2005.07.020
• Nantaphol, S., Chailapakul, O., & Siangproh, W. (2015). Sensitive and selective electrochemical sensor using silver nanoparticles modified glassy carbon electrode for determination of cholesterol in bovine serum. Sensors and Actuators B: Chemical, 207, 193–198. https://doi.org/10.1016/j.snb.2014.10.041
• Payal, R., Saroj, M. K., Sharma, N., & Rastogi, R. C. (2018). Photophysical behavior of some thymol based schiff bases using absorption and fluorescence spectroscopy. Journal of Luminescence, 198, 92–102. https://doi.org/10.1016/j.jlumin.2018.02.007
• Pervaiz, M., Shahin, M., Ejaz, A., Quratulain, R., Saeed, Z., Ashraf, A., … Younas, U. (2024). An overview of Aniline-Based Schiff base metal Complexes: Synthesis, characterization and biological activities - a review. Inorganic Chemistry Communications, 159, 111851. https://doi.org/10.1016/j.inoche.2023.111851
• Raczuk, E., Dmochowska, B., Samaszko-Fiertek, J., & Madaj, J. (2022). Different Schiff Bases—Structure, Importance and Classification. Molecules, 27(3), 787. https://doi.org/10.3390/molecules27030787
• Ryazanova, O. A., Voloshin, I. M., Makitruk, V. L., Zozulya, V. N., & Karachevtsev, V. A. (2007). pH-Induced changes in electronic absorption and fluorescence spectra of phenazine derivatives. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 66(4–5), 849–859. https://doi.org/10.1016/j.saa.2006.04.027
• Shatir, T. M., Aly, K. A., Ebrahium, M. M., Saddeek, Y. B., & Ranjith Kumar, E. (2024). Linear and non-linear optical and dielectric properties of transition metals complexes films derived from Azo-Schiff base for photovoltaic applications. Journal of Molecular Liquids, 401, 124636. https://doi.org/10.1016/j.molliq.2024.124636
• Shu, J., Ni, T., Liu, X., Xu, B., Liu, L., Chu, W., … Jiang, W. (2021). Mechanochromism, thermochromism, protonation effect and discrimination of CHCl3 from organic solvents in a Et2N-substituted Salicylaldehyde Schiff base. Dyes and Pigments, 195, 109708. https://doi.org/10.1016/j.dyepig.2021.109708
• Silva, R. C., Canisares, F. S. M., Mutti, A. M. G., Pires, A. M., & Lima, S. A. M. (2023). Small Schiff base molecules derived from salicylaldehyde as colorimetric and fluorescent neutral-to-basic pH sensors. Dyes and Pigments, 213, 111191. https://doi.org/10.1016/j.dyepig.2023.111191
• Xiao, D., Qi, H., Teng, Y., Pierre, D., Kutoka, P. T., & Liu, D. (2021). Advances and Challenges of Fluorescent Nanomaterials for Synthesis and Biomedical Applications. Nanoscale Research Letters, 16(1), 167. https://doi.org/10.1186/s11671-021-03613-z
• Yıldırım, N., & Yıldız, M. (2018). A Schiff Base Sensor Selective to Anions, Biological Activity and Spectral Studies. Journal of the Turkish Chemical Society Section A: Chemistry, 5(3), 1271–1278. https://doi.org/10.18596/jotcsa.431554
• Zurnacı, M., Şener, İ., Gür, M., & Şener, N. (2022). Study on Photophysical Properties of Novel Fluorescent Phenanthroimidazole-Thiadiazole Hybrid Derivatives. Journal of Fluorescence, 32(3), 1155–1169. https://doi.org/10.1007/s10895-022-02916-3