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Reduced texaphyrin: A ratiometric optical sensor for heavy metals in aqueous solution

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We report here a water-soluble metal cation sensor system based on the as-prepared or reduced form of an expanded porphyrin, texaphyrin. Upon metal complexation, a change in the redox state of the ligand occurs that is accompanied by a color change from red to green. Although long employed for synthesis in organic media, we have now found that this complexation-driven redox behavior may be used to achieve the naked eye detectable colorimetric sensing of several number of less-common metal ions in aqueous media. Exposure to In(III), Hg(II), Cd(II), Mn(II), Bi(III), Co(II), and Pb(II) cations leads to a colorimetric response within 10 min. This process is selective for Hg(II) under conditions of competitive analysis. Furthermore, among the subset of response-producing cations, In(III) proved unique in giving rise to a ratiometric change in the ligand-based fluorescence features, including an overall increase in intensity. The cation selectivity observed in aqueous media stands in contrast to what is seen in organic solvents, where a wide range of texaphyrin metal complexes may be prepared. The formation of metal cation complexes under the present aqueous conditions was confirmed by reversed phase high-performance liquid chromatography, ultra-violet-visible absorption and fluorescence spectroscopies, and high-resolution mass spectrometry.

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  1. 1.

    Wu D, Sedgwick A C, Gunnlaugsson T, Akkaya E U, Yoon J, James T D. Fluorescent chemosensors: The past, present, and future. Chemical Society Review, 2017, 46(23): 7105–7123

  2. 2.

    Li Z, Askim J R, Suslick K S. The optoelectronic nose: Colorimetric and fluorometric sensor arrays. Chemical Reviews, 2019, 119(1): 231–292

  3. 3.

    Kaur B, Kaur N, Kumar S. Colorimetric metal ion sensors—a comprehensive review of the years 2011–2016. Coordination Chemistry Reviews, 2018, 358: 13–69

  4. 4.

    Piriya A, Joseph P, Daniel K, Lakshmanan S, Kinoshita T, Muthusamy S. Colorimetric sensors for rapid detection of various analytes. Materials Science and Engineering C, 2017, 78: 1231–1245

  5. 5.

    Long F, Zhu A, Shi H, Wang H, Liu J. Rapid on-site/in-situ detection of heavy metal ions in environmental water using a structure-switching DNA optical biosensor. Scientific Reports, 2013, 3(1): 1–7

  6. 6.

    Zhou W, Saran R, Liu J. Metal sensing by DNA. Chemical Reviews, 2017, 117(12): 8272–8325

  7. 7.

    Nolan E M, Lippard S J. Turn-on and ratiometric mercury sensing in water with a red-emitting probe. Journal of the American Chemical Society, 2007, 129(18): 5910–5918

  8. 8.

    Azmi N A, Ahmad S H, Low S C. Detection of mercury ions in water using a membrane-based colorimetric sensor. RSC Advances, 2018, 8(1): 251–261

  9. 9.

    Chang J, Zhou G, Gao X, Mao S, Cui S, Ocola L E, Yuan C, Chen J. Real-time detection of mercury ions in water using a reduced graphene oxide/DNA field-effect transistor with assistance of a passivation layer. Sensing and Bio-Sensing Research, 2015, 5: 97–104

  10. 10.

    Karthikeyan K, Sujatha L. Fluorometric sensor for mercury ion detection in a fluidic MEMS device. IEEE Sensors Journal, 2018, 18(13): 5225–5231

  11. 11.

    Maher S, Bastani B, Smith B, Jjunju Z, Taylor S, Young I S. Portable fluorescent sensing array for monitoring heavy metals in water. IEEE Sensors, 2016: 1–3

  12. 12.

    He W, Luo L, Liu Q, Chen Z. Colorimetric sensor array for discrimination of heavy metal ions in aqueous solution based on three kinds of thiols as receptors. Analytical Chemistry, 2018, 90(7): 4770–4775

  13. 13.

    Niu L, Li H, Feng L, Guan Y, Chen Y, Duan C, Wu L, Guan Y, Tung C, Yang Q. BODIPY-based fluorometric sensor array for the highly sensitive identification of heavy-metal ions. Analytica Chimica Acta, 2013, 775: 93–99

  14. 14.

    Singh R K, Mishra S, Jena S, Panigrahi B, Das B, Jayabalan R, Parhi P K, Mandal D. Rapid colorimetric sensing of gadolinium by EGCG-derived AgNPs: The development of a nanohybrid bioimaging probe. Chemical Communications, 2018, 54(32): 3981–3984

  15. 15.

    Denis M, Pancholi J, Jobe K, Watkinson M, Goldup S M. Chelating rotaxane ligands as fluorescent sensors for metal ions. Angewandte Chemie International Edition, 2018, 57(19): 5310–5314

  16. 16.

    Hong W, Li W, Hu X, Zhao B, Zhang F, Zhang D. Highly sensitive colorimetric sensing for heavy metal ions by strong polyelectrolyte photonic hydrogels. Journal of Materials Chemistry, 2011, 21(43): 17193–17201

  17. 17.

    Moghaddam M R, Carrara S, Hogan C F. Multi-colour bipolar electrochemiluminescence for heavy metal ion detection. Chemical Communications, 2018, 55(8): 3–6

  18. 18.

    Boening D W. Ecological effects, transport, and fate of Mercury: A general review. Chemosphere, 2000, 40(12): 1335–1351

  19. 19.

    Zheng W, Aschner M, Ghersi-egea J. Brain barrier systems: A new frontier in metal neurotoxicological research. Toxicology and Applied Pharmacology, 2003, 192(1): 1–11

  20. 20.

    Selid P D, Xu H, Collins E M, Face-Collins M S, Zhao J X. Sensing mercury for biomedical and environmental monitoring. Sensors (Basel), 2009, 9(7): 5446–5459

  21. 21.

    Hu J, Wu T, Zhang G, Liu S. Highly selective fluorescence sensing of mercury ions over a broad concentration range based on mixed polymeric micelles. Macromolecules, 2012, 45(9): 3939–3947

  22. 22.

    Nolan E M, Lippard S J. Tools and tactics for the optical detection of mercuric ion. Chemical Reviews, 2008, 108(9): 3443–3480

  23. 23.

    Zhang K, Wu Y, Wang W, Li B, Zhang Y, Zuo T. Resources, conservation and recycling indium from waste LCDs: A review. Resources, Conservation and Recycling, 2015, 104: 276–290

  24. 24.

    Thakur M L, Welch M J, Joist J H, Coleman R E. Indium-III labeled platelets: Studies on preparation and evaluation of in vitro and in vivo functions. Thrombosis Research, 1976, 9(4): 345–357

  25. 25.

    Thakur M, Lavender J P, Arnot R, Silvester D J, Segal A W. Indium-III-labeled autologous leukocytes in man. Journal of Nuclear Medicine, 1977, 18(10): 1014–1021

  26. 26.

    Zolata H, Abbasi F, Afarideh H. Synthesis, characterization and theranostic evaluation of indium-III labeled multifunctional super-paramagnetic iron oxide nanoparticles. Nuclear Medicine and Biology, 2015, 42(2): 164–170

  27. 27.

    Alfantazi A M, Moskalyk R R. Processing of indium: A review. Materials & Design, 2003, 16(8): 687–694

  28. 28.

    Lim C H, Han J, Cho H, Kang M. Studies on the toxicity and distribution of indium compounds according to particle size in sprague-dawley rats. Toxicological Research, 2014, 30(1): 55–63

  29. 29.

    Tanaka A, Hirata M, Kiyohara Y, Nakano M, Omae K, Shiratani M, Koga K. Review of pulmonary toxicity of indium compounds to animals and humans. Thin Solid Films, 2010, 518(11): 2934–2936

  30. 30.

    Mehta P K, Hwang G W, Park J, Lee K. Highly sensitive ratiometric fluorescent detection of indium(III) using fluorescent probe based on phosphoserine as a receptor. Analytical Chemistry, 2018, 90(19): 11256–11264

  31. 31.

    Wu Y C, Li H, Yang H. A sensitive and highly selective fluorescent sensor for In3+. Organic & Biomolecular Chemistry, 2010, 8(15): 3394–3397

  32. 32.

    Kim S K, Kim S H, Kim H J, Lee S H, Lee S W, Ko J, Bartsch R A, Kim J S. Indium(III)-induced fluorescent excimer formation and extinction in calix[4]arene—fluoroionophores. Inorganic Chemistry, 2005, 44(22): 7866–7875

  33. 33.

    Ding Y, Zhu W, Xie Y. Development of ion chemosensors based on porphyrin analogues. Chemical Reviews, 2017, 117(4): 2203–2256

  34. 34.

    Sessler J L, Mody T D, Hemmi G W, Lynch V. Synthesis and structural characterization of lanthanide(III) texaphyrins. Inorganic Chemistry, 1993, 32(14): 3175–3187

  35. 35.

    Preihs C, Arambula J F, Lynch V M, Siddik H, Sessler J L. Bismuthand lead-texaphyrin complexes: Towards potential α-core emitters for radiotherapy. Chemical Communications, 2010, 46(42): 7900–7902

  36. 36.

    Thiabaud G, Radchenko V, Wilson J J, John K D, Birnbaum E R, Sessler J L. Rapid insertion of bismuth radioactive isotopes into texaphyrin in aqueous media. Journal of Porphyrins and Phthalocyanines, 2017, 21(12): 882–886

  37. 37.

    Maiya B G, Harriman A, Sessler J L, Hemmi G, Murai T, Mallouk T E. Ground- and excited-state spectral and redox properties of cadmium(II) texaphyrin. Journal of Physical Chemistry, 1989, 93(24): 8111–8115

  38. 38.

    Sessler J L, Murai T, Lynch V, Cyr M. An “expanded porphyrin”: The synthesis and structure of a new aromatic pentadentate ligand of chemistry. Journal of the American Chemical Society, 1988, 110(16): 5586–5588

  39. 39.

    Sessler J L, Dow W C, Connor D O, Harriman A, Hemmi G, Mody T D, Miller R A, Qing F, Springs S, Woodburn K, et al. Biomedical applications of lanthanide(III) texaphyrins lutetium(III) texaphyrins as potential photodynamic therapy photosensitizers. Journal of Alloys and Compounds, 1997, 249(1–2): 146–152

  40. 40.

    Magda D, Miller R A. Motexafin gadolinium: A novel redox active drug for cancer therapy. Seminars in Cancer Biology, 2006, 16(6): 466–476

  41. 41.

    Hannah S, Lynch V, Guldi D M, Gerasimchuk N, Macdonald C L B, Magda D, Sessler J L. Late first-row transition-metal complexes of texaphyrin. Journal of the American Chemical Society, 2002, 124(28): 8416–8427

  42. 42.

    Thiabaud G, Arambula J F, Siddik Z H, Sessler J L. Photoinduced reduction of Pt IV within an anti-proliferative Pt IV-texaphyrin conjugate. Chemistry (Weinheim an der Bergstrasse, Germany), 2014, 20(29): 8942–8947

  43. 43.

    Thiabaud G, Mccall R, He G, Arambula J F, Siddik Z H, Sessler J L. Activation of platinum(IV) prodrugs by motexafin gadolinium as a redox mediator. Angewandte Chemie International Edition, 2016, 55(41): 12626–12631

  44. 44.

    Arambula J F, Sessler J L, Siddik Z H. Overcoming biochemical pharmacologic mechanisms of platinum resistance with a texaphyrin-platinum conjugate. Bioorganic & Medicinal Chemistry Letters, 2011, 21(6): 1701–1705

  45. 45.

    Arambula J F, Sessler J L, Siddik Z H. A texaphyrin-oxaliplatin conjugate that overcomes both pharmacologic and molecular mechanisms of cisplatin resistance in cancer cells. MedChemComm, 2012, 3(10): 1275–1281

  46. 46.

    Lee M H, Kim E J, Park S Y, Hong K S, Kim S, Sessler J L. Acid-triggered release of doxorubicin from a hydrazone-linked Gd3+-texaphyrin conjugate. Chemical Communications, 2016, 52(69): 10551–10554

  47. 47.

    Blesic M, Melo E, Petrovski Z, Plechkova N V, Lopes N C, Seddon K R, Rebelo P N. On the self-aggregation and fluorescence quenching aptitude of surfactant ionic liquids. Journal of Physical Chemistry B, 2008, 112(29): 8645–8650

  48. 48.

    Mei J, Leung N L C, Kwok R T K, Lam J W Y, Tang B Z. Aggregation-induced emission: Together we shine, united we soar! Chemical Reviews, 2015, 115(21): 11718–11940

  49. 49.

    Quinn S D, Magennis S W. Optical detection of gadolinium(III) ions via quantum dot aggregation. RSC Advances, 2017, 7(40): 2470–2475

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This work was supported by the National Institutes of Health (Grants CA68682 to J.L.S.) and the Robert A. Welch Foundation (F-0018). HDR would like to thank UT Austin for a Scientist in Residence Fellowship and the Los Alamos National Lab for a Seaborg Fellowship.

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Correspondence to Jonathan L. Sessler.

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Root, H.D., Thiabaud, G. & Sessler, J.L. Reduced texaphyrin: A ratiometric optical sensor for heavy metals in aqueous solution. Front. Chem. Sci. Eng. 14, 19–27 (2020).

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  • texaphyrin
  • fluorescent sensor
  • ion-sensing
  • indium
  • mercury