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Electric Cell-Substrate Sensing for Real-Time Evaluation of Metal-Organic Framework Toxicological Profiles

Published: May 26th, 2023



1Department of Chemical and Biomedical Engineering, West Virginia University, 2Department of Anthropology for Energy, West Virginia University, 3Department of Hospitality and Tourism, West Virginia University

The following study evaluates the toxicological profile of a selected metal-organic framework utilizing electric cell-substrate impedance sensing (ECIS), a real-time, high-throughput screening technique.

Metal-organic frameworks (MOFs) are hybrids formed through the coordination of metal ions and organic linkers in organic solvents. The implementation of MOFs in biomedical and industrial applications has led to concerns regarding their safety. Herein, the profile of a selected MOF, a zeolitic imidazole framework, was evaluated upon exposure to human lung epithelial cells. The platform for evaluation was a real-time technique (i.e., electric cell-substrate impedance sensing [ECIS]). This study identifies and discusses some of the deleterious effects of the selected MOF on the exposed cells. Furthermore, this study demonstrates the benefits of using the real-time method versus other biochemical assays for comprehensive cell evaluations. The study concludes that observed changes in cell behavior could hint at possible toxicity induced upon exposure to MOFs of different physicochemical characteristics and the dosage of those frameworks being used. By understanding changes in cell behavior, one foresees the ability to improve safe-by-design strategies of MOFs to be used for biomedical applications by specifically tailoring their physicochemical characteristics.

Metal-organic frameworks (MOFs) are hybrids formed through the combination of metal ions and organic linkers1,2 in organic solvents. Due to the variety of such combinations, MOFs possess structural diversity3, tunable porosity, high thermal stability, and high surface areas4,5. Such characteristics make them attractive candidates in a variety of applications, from gas storage6,7 to catalysis8,9, and from contrast....

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1. ZIF-8 synthesis

  1. For the purpose of this example, use a 1:10:100 (metal:linker:solvent) mass ratio to synthesize the ZIF-8. For this, measure out zinc nitrate hexahydrate, and record the measurement. Utilize the example mass ratio to calculate the amount needed for the linker, 2-methylimidazole, and the solvent (i.e., methanol).
  2. Place the zinc nitrate hexahydrate and linker into two different glass vials. Add half of the calculated amount of methanol to the zinc nitrate hexahydrat.......

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Using a common in vitro model cell line39 (BEAS-2B), this study aimed to demonstrate the feasibility and applicability of ECIS to assess changes in cell behavior upon exposure to a lab-synthesized MOF. These changes assessment was complemented by analysis through conventional colorimetric assays.

The physicochemical characteristics of the framework were first evaluated to ensure the reproducibility of the methods employed, the validity of the obtained.......

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Previous analysis showed that ECIS could be used to assess the behavior of cells exposed to analytes (i.e., carbon nanotubes35, drugs43, or nanoclays16). Furthermore, Stueckle et al. used ECIS to evaluate the toxicity of BEAS-2B cells exposed to nanoclays and their byproducts and found that the cellular behavior and attachment were dependent on the physicochemical characteristics of such materials42. Herein, we proposed to det.......

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This work was funded in part by the National Institute of General Medical Sciences (NIGMS) T32 program (T32 GM133369) and the National Science Foundation (NSF 1454230). Additionally, WVU Shared Research Facilities and Applied Biophysics assistance and support are acknowledged.


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Name Company Catalog Number Comments
 4-[3-(4-idophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzene disulfonate (WST-1 assay)  Roche 5015944001
0.25% Trypsin-EDTA (1x) Gibco 25255-056
100 mm plates Corning 430167
1300 Series A2 biofume hood Thermo Scientific 323TS
2510 Branson bath sonicator Process Equipment & Supply, Inc.  251OR-DTH
2-methylimidazole, 97% Alfa Aesar 693-98-1
5 mL sterile microtube Argos Technologies T2076S-CA
50 mL  tubes  Falcon 352098
96W10idf well plates Applied Biophysics  96W10idf PET
96-well plates Fisherbrand FB012931
Biorender Biorender N/A
Countess cell counting chamber slides Invitrogen C10283
Countess II FL automated cell counter Life Technologies C0916-186A-0303
Denton Desk V sputter and carbon coater Denton Vacuum N/A
Dimethly sulfoxide  Corning 25-950-CQC
DPBS/Modified Cytiva SH30028.02
Dulbecco's modified Eagle medium Corning 10-014-CV
ECIS-ZΘ Applied Biophysics  ABP 1129
Excel Microsoft Version 2301
Falcon tubes (15 mL) Corning 352196
Fetal bovine serum Gibco 16140-071
FLUOstar OPTIMA plate reader BMG LABTECH 413-2132
GraphPad Prism Software (9.0.0) GraphPad Software, LLC Version 9.0.0
HERAcell 150i CO2 Incubator Thermo Scientific 50116047
Hitachi S-4700 Field emission scanning electron microscope equipped with energy dispersive X-ray  Hitachi High-Technologies Corporation S4700 and EDAX TEAM analysis software
ImageJ software National Institutes of Health N/A
Immortalized human bronchial epithelial cells American Type Culture Collection CRL-9609
Isotemp freezer Fisher Scientific 
Methanol, 99% Fisher Chemical 67-56-1
Parafilm sealing film The Lab Depot HS234526A
Penicillin/Steptomycin Gibco 15140-122
Sorvall Legend X1R Centrifuge  Thermo Scientific 75004220
Sorvall T 6000B DU PONT  T6000B
Trypan blue, 0.4% solution in PBS MP Biomedicals, LLC 1691049
Vacuum Chamber Belart 999320237
Zinc Nitrate Hexahydrate, 98% extra pure Acros Organic 101-96-18-9

  1. Tamames-Tabar, C., et al. Cytotoxicity of nanoscaled metal-organic frameworks. Journal of Materials Chemistry. B. 2 (3), 262-271 (2014).
  2. Lin, W. X., et al. Low cytotoxic metal-organic frameworks as temperature-responsive drug carriers. ChemPlusChem. 81 (8), 804-810 (2016).
  3. Vasconcelos, I. B., et al. Cytotoxicity and slow release of the anti-cancer drug doxorubicin from ZIF-8. RSC Advances. 2 (25), 9437-9442 (2012).
  4. Yang, B. C., Shen, M., Liu, J. Q., Ren, F. Post-synthetic modification nanoscale metal-organic frameworks for targeted drug delivery in cancer cells. Pharmaceutical Research. 34 (11), 2440-2450 (2017).
  5. Lucena, M. A. M., et al. Application of the metal-organic framework Eu(BTC) as a luminescent marker for gunshot residues: A synthesis, characterization, and toxicity study. ACS Applied Materials & Interfaces. 9 (5), 4684-4691 (2017).
  6. Kayal, S., Sun, B. C., Chakraborty, A. Study of metal-organic framework MIL-101(Cr) for natural gas (methane) storage and compare with other MOFs (metal-organic frameworks). Energy. 91, 772-781 (2015).
  7. Gutov, O. V., et al. Water-stable zirconium-based metal-organic framework material with high-surface area and gas-storage capacities. Chemistry. 20 (39), 12389-12393 (2014).
  8. Ghorbanloo, M., Safarifard, V., Morsali, A. Heterogeneous catalysis with a coordination modulation synthesized MOF: morphology-dependent catalytic activity. New Journal of Chemistry. 41 (10), 3957-3965 (2017).
  9. Valvekens, P., et al. Base catalytic activity of alkaline earth MOFs: a (micro) spectroscopic study of active site formation by the controlled transformation of structural anions. Chemical Science. 5 (11), 4517-4524 (2014).
  10. Taylor, K. M. L., Rieter, W. J., Lin, W. B. Manganese-based nanoscale metal-organic frameworks for magnetic resonance imaging. Journal of the American Chemical Society. 130 (44), 14358-14359 (2008).
  11. Taylor-Pashow, K. M. L., Della Rocca, J., Xie, Z. G., Tran, S., Lin, W. B. Postsynthetic modifications of iron-carboxylate nanoscale metal-organic frameworks for imaging and drug delivery. Journal of the American Chemical Society. 131 (40), 14261-14263 (2009).
  12. Kundu, T., et al. Mechanical downsizing of a gadolinium(III)-based metal-organic framework for anticancer drug delivery. Chemistry. 20 (33), 10514-10518 (2014).
  13. Orellana-Tavra, C., et al. Drug delivery and controlled release from biocompatible metal-organic frameworks using mechanical amorphization. Journal of Materials Chemistry. B. 4 (47), 7697-7707 (2016).
  14. Su, H. M., et al. A highly porous medical metal-organic framework constructed from bioactive curcumin. Chemical Communications. 51 (26), 5774-5777 (2015).
  15. Gandara-Loe, J., et al. Metal-organic frameworks as drug delivery platforms for ocular therapeutics. ACS Applied Materials & Interfaces. 11 (2), 1924-1931 (2019).
  16. Wagner, A., et al. Toxicity screening of two prevalent metal organic frameworks for therapeutic use in human lung epithelial cells. International Journal of Nanomedicine. 14, 7583-7591 (2019).
  17. Chen, G. S., et al. In vitro toxicity study of a porous iron(III) metal-organic framework. Molecules. 24 (7), 1211 (2019).
  18. Eldawud, R., Wagner, A., Dong, C. B., Rojansakul, Y., Dinu, C. Z. Electronic platform for real-time multi-parametric analysis of cellular behavior post-exposure to single-walled carbon nanotubes. Biosensors & Bioelectronics. 71, 269-277 (2015).
  19. Kroll, A., Pillukat, M. H., Hahn, D., Schnekenburger, J. Current in vitro methods in nanoparticle risk assessment: Limitations and challenges. European Journal of Pharmaceutics and Biopharmaceutics. 72 (2), 370-377 (2009).
  20. Lucena, F. R. S., et al. Induction of cancer cell death by apoptosis and slow release of 5-fluoracil from metal-organic frameworks Cu-BTC. Biomedicine & Pharmacotherapy. 67 (8), 707-713 (2013).
  21. Orellana-Tavra, C., et al. Tuning the endocytosis mechanism of Zr-based metal-organic frameworks through linker functionalization. ACS Applied Materials & Interfaces. 9 (41), 35516-35525 (2017).
  22. Zucker, R. M., Ortenzio, J. N. R., Boyes, W. K. Characterization, detection, and counting of metal nanoparticles using flow cytometry. Cytometry. Part A. 89 (2), 169-183 (2016).
  23. Robson, A. L., et al. Advantages and limitations of current imaging techniques for characterizing liposome morphology. Frontiers in Pharmacology. 9, 80 (2018).
  24. Giaever, I., Keese, C. R. Micromotion of mammalian cells measured electrically. Proceedings of the National Academy of Sciences. 88 (17), 7896-7900 (1991).
  25. Wegener, J., Keese, C. R., Giaever, I. Electric cell-substrate impedance sensing (ECIS) as a noninvasive means to monitor the kinetics of cell spreading to artificial surfaces. Experimental Cell Research. 259 (1), 158-166 (2000).
  26. Wagner, A., et al. Toxicity evaluations of nanoclays and thermally degraded byproducts through spectroscopical and microscopical approaches. Biochimica et Biophysica Acta. General Subjects. 1861, 3406-3415 (2017).
  27. Wagner, A., et al. Early assessment and correlations of nanoclay's toxicity to their physical and chemical properties. ACS Applied Materials & Interfaces. 9 (37), 32323-32335 (2017).
  28. Wagner, A., et al. Incineration of nanoclay composites leads to byproducts with reduced cellular reactivity. Scientific Reports. 8 (1), 10709 (2018).
  29. Zhao, F., Klimecki, W. T. Culture conditions profoundly impact phenotype in BEAS-2B, a human pulmonary epithelial model. Journal of Applied Toxicology. 35 (8), 945-951 (2015).
  30. Wu, S. X., Wang, W. H., Fang, Y. Z., Kong, X. J., Liu, J. H. Efficient Friedel-Crafts acylation of anisole over silicotungstic acid modified ZIF-8. Reaction Kinetics Mechanisms and Catalysis. 122, 357-367 (2017).
  31. Shu, F. P., et al. Fabrication of a hyaluronic acid conjugated metal organic framework for targeted drug delivery and magnetic resonance imaging. RSC Advances. 8 (12), 6581-6589 (2018).
  32. Shi, Z. Q., et al. FA-PEG decorated MOF nanoparticles as a targeted drug delivery system for controlled release of an autophagy inhibitor. Biomaterials Science. 6 (10), 2582-2590 (2018).
  33. Ebrahim, A. S., et al. Functional optimization of electric cell-substrate impedance sensing (ECIS) using human corneal epithelial cells. Scientific Reports. 12 (1), 14126 (2022).
  34. Szulcek, R., Bogaard, H. J., van Nieuw Amerongen, G. P. Electric cell-substrate impedance sensing for the quantification of endothelial proliferation, barrier function, and motility. Journal of Visualized Experiments. (85), e51300 (2014).
  35. Eldawud, R., et al. Carbon nanotubes physicochemical properties influence the overall cellular behavior and fate. Nanoimpact. 9, 72-84 (2018).
  36. An, Y., Jin, T. Y., Zhang, F., He, P. Electric cell-substrate impedance sensing (ECIS) for profiling cytotoxicity of cigarette smoke. Journal of Electroanalytical Chemistry. 834, 180-186 (2019).
  37. Kaur, G., Dufour, J. M. Cell lines. Spermatogenesis. 2 (1), 1-5 (2012).
  38. . Allied Biophysics Available from: (2023)
  39. Park, Y. H., Kim, D., Dai, J., Zhang, Z. Human bronchial epithelial BEAS-2B cells, an appropriate in vitro model to study heavy metals induced carcinogenesis. Toxicology and Applied Pharmacology. 287 (3), 240-245 (2015).
  40. Yang, F., et al. Morphological map of ZIF-8 crystals with five distinctive shapes: Feature of filler in mixed-matrix membranes on C3H6/C3H8 separation. Chemistry of Materials. 30 (10), 3467-3473 (2018).
  41. Rose, O. L., et al. Thin films of metal-organic framework interfaces obtained by laser evaporation. Nanomaterials. 11 (6), 1367 (2021).
  42. Stueckle, T. A., et al. Impacts of organomodified nanoclays and their incinerated byproducts on bronchial cell monolayer integrity. Chemical Research in Toxicology. 32 (12), 2445-2458 (2019).
  43. Eldawud, R., et al. Potential antitumor activity of digitoxin and user-designed analog administered to human lung cancer cells. Biochimica et Biophysica Acta. General Subjects. 1864 (11), 129683 (2020).
  44. Zhuang, J., et al. Optimized metal-organic-framework nanospheres for drug delivery: Evaluation of small-molecule encapsulation. ACS Nano. 8 (3), 2812-2819 (2014).
  45. Eldawud, R., et al. Combinatorial approaches to evaluate nanodiamond uptake and induced cellular fate. Nanotechnology. 27 (8), 085107 (2016).
  46. Houthaeve, G., De Smedt, S. C., Braeckmans, K., De Vos, W. H. The cellular response to plasma membrane disruption for nanomaterial delivery. Nano Convergence. 9 (1), 6 (2022).
  47. Otero-Gonzalez, L., Sierra-Alvarez, R., Boitano, S., Field, J. A. Application and validation of an impedance-based real time cell analyzer to measure the toxicity of nanoparticles impacting human bronchial epithelial cells. Environmental Science & Technology. 46 (18), 10271-10278 (2012).
  48. Ibarguren, M., Lopez, D. J., Escriba, P. V. The effect of natural and synthetic fatty acids on membrane structure, microdomain organization, cellular functions and human health. Biochimica et Biophysica Acta. 1838 (6), 1518-1528 (2014).
  49. Nor, Y. A., et al. Shaping nanoparticles with hydrophilic compositions and hydrophobic properties as nanocarriers for antibiotic delivery. ACS Central Science. 1 (6), 328-334 (2015).
  50. Farcal, L., et al. Comprehensive in vitro toxicity testing of a panel of representative oxide nanomaterials: First steps towards an intelligent testing strategy. PLoS One. 10 (5), e0127174 (2015).
  51. Verma, N. K., Moore, E., Blau, W., Volkov, Y., Babu, P. R. Cytotoxicity evaluation of nanoclays in human epithelial cell line A549 using high content screening and real-time impedance analysis. Journal of Nanoparticle Research. 14, 1137 (2012).
  52. Xiao, C. D., Lachance, B., Sunahara, G., Luong, J. H. T. Assessment of cytotoxicity using electric cell-substrate impedance sensing: Concentration and time response function approach. Analytical Chemistry. 74 (22), 5748-5753 (2002).
  53. Coyle, J. P., et al. Carbon nanotube filler enhances incinerated thermoplastics-induced cytotoxicity and metabolic disruption in vitro. Particle and Fibre Toxicology. 17 (1), 40 (2020).
  54. Yu, M. H., et al. Hyaluronic acid modified mesoporous silica nanoparticles for targeted drug delivery to CD44-overexpressing cancer cells. Nanoscale. 5 (1), 178-183 (2013).

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