Growth-Based Bacterial Viability Assay for Interference-Free and High-Throughput Toxicity Screening of Nanomaterials

Tian A. Qiu, Thu Ha Thi Nguyen, Natalie V. Hudson-Smith, Peter L. Clement, Dona Carla Forester, Hilena Frew, Mimi N. Hang, Catherine J. Murphy, Robert J. Hamers, Z. Vivian Feng, Christy L. Haynes

Research output: Contribution to journalArticle

Abstract

Current high-throughput approaches evaluating toxicity of chemical agents toward bacteria typically rely on optical assays, such as luminescence and absorbance, to probe the viability of the bacteria. However, when applied to toxicity induced by nanomaterials, scattering and absorbance from the nanomaterials act as interferences that complicate quantitative analysis. Herein, we describe a bacterial viability assay that is free of optical interference from nanomaterials and can be performed in a high-throughput format on 96-well plates. In this assay, bacteria were exposed to various materials and then diluted by a large factor into fresh growth medium. The large dilution ensured minimal optical interference from the nanomaterial when reading optical density, and the residue left from the exposure mixture after dilution was confirmed not to impact the bacterial growth profile. The fractions of viable cells after exposure were allowed to grow in fresh medium to generate measurable growth curves. Bacterial viability was then quantitatively correlated to the delay of bacterial growth compared to a reference regarded as 100% viable cells; data analysis was inspired by that in quantitative polymerase chain reactions, where the delay in the amplification curve is correlated to the starting amount of the template nucleic acid. Fast and robust data analysis was achieved by developing computer algorithms carried out using R. This method was tested on four bacterial strains, including both Gram-negative and Gram-positive bacteria, showing great potential for application to all culturable bacterial strains. With the increasing diversity of engineered nanomaterials being considered for large-scale use, this high-throughput screening method will facilitate rapid screening of nanomaterial toxicity and thus inform the risk assessment of nanoparticles in a timely fashion.

Original languageEnglish (US)
Pages (from-to)2057-2064
Number of pages8
JournalAnalytical chemistry
Volume89
Issue number3
DOIs
StatePublished - Feb 7 2017

Fingerprint

Nanostructured materials
Toxicity
Assays
Screening
Throughput
Bacteria
Light interference
Dilution
Density (optical)
Polymerase chain reaction
Risk assessment
Nucleic Acids
Amplification
Luminescence
Scattering
Nanoparticles
Chemical analysis

ASJC Scopus subject areas

  • Analytical Chemistry

Cite this

Qiu, T. A., Nguyen, T. H. T., Hudson-Smith, N. V., Clement, P. L., Forester, D. C., Frew, H., ... Haynes, C. L. (2017). Growth-Based Bacterial Viability Assay for Interference-Free and High-Throughput Toxicity Screening of Nanomaterials. Analytical chemistry, 89(3), 2057-2064. https://doi.org/10.1021/acs.analchem.6b04652

Growth-Based Bacterial Viability Assay for Interference-Free and High-Throughput Toxicity Screening of Nanomaterials. / Qiu, Tian A.; Nguyen, Thu Ha Thi; Hudson-Smith, Natalie V.; Clement, Peter L.; Forester, Dona Carla; Frew, Hilena; Hang, Mimi N.; Murphy, Catherine J.; Hamers, Robert J.; Feng, Z. Vivian; Haynes, Christy L.

In: Analytical chemistry, Vol. 89, No. 3, 07.02.2017, p. 2057-2064.

Research output: Contribution to journalArticle

Qiu, TA, Nguyen, THT, Hudson-Smith, NV, Clement, PL, Forester, DC, Frew, H, Hang, MN, Murphy, CJ, Hamers, RJ, Feng, ZV & Haynes, CL 2017, 'Growth-Based Bacterial Viability Assay for Interference-Free and High-Throughput Toxicity Screening of Nanomaterials', Analytical chemistry, vol. 89, no. 3, pp. 2057-2064. https://doi.org/10.1021/acs.analchem.6b04652
Qiu, Tian A. ; Nguyen, Thu Ha Thi ; Hudson-Smith, Natalie V. ; Clement, Peter L. ; Forester, Dona Carla ; Frew, Hilena ; Hang, Mimi N. ; Murphy, Catherine J. ; Hamers, Robert J. ; Feng, Z. Vivian ; Haynes, Christy L. / Growth-Based Bacterial Viability Assay for Interference-Free and High-Throughput Toxicity Screening of Nanomaterials. In: Analytical chemistry. 2017 ; Vol. 89, No. 3. pp. 2057-2064.
@article{4edbdc19b8b743498c0ac3ca029f3d92,
title = "Growth-Based Bacterial Viability Assay for Interference-Free and High-Throughput Toxicity Screening of Nanomaterials",
abstract = "Current high-throughput approaches evaluating toxicity of chemical agents toward bacteria typically rely on optical assays, such as luminescence and absorbance, to probe the viability of the bacteria. However, when applied to toxicity induced by nanomaterials, scattering and absorbance from the nanomaterials act as interferences that complicate quantitative analysis. Herein, we describe a bacterial viability assay that is free of optical interference from nanomaterials and can be performed in a high-throughput format on 96-well plates. In this assay, bacteria were exposed to various materials and then diluted by a large factor into fresh growth medium. The large dilution ensured minimal optical interference from the nanomaterial when reading optical density, and the residue left from the exposure mixture after dilution was confirmed not to impact the bacterial growth profile. The fractions of viable cells after exposure were allowed to grow in fresh medium to generate measurable growth curves. Bacterial viability was then quantitatively correlated to the delay of bacterial growth compared to a reference regarded as 100{\%} viable cells; data analysis was inspired by that in quantitative polymerase chain reactions, where the delay in the amplification curve is correlated to the starting amount of the template nucleic acid. Fast and robust data analysis was achieved by developing computer algorithms carried out using R. This method was tested on four bacterial strains, including both Gram-negative and Gram-positive bacteria, showing great potential for application to all culturable bacterial strains. With the increasing diversity of engineered nanomaterials being considered for large-scale use, this high-throughput screening method will facilitate rapid screening of nanomaterial toxicity and thus inform the risk assessment of nanoparticles in a timely fashion.",
author = "Qiu, {Tian A.} and Nguyen, {Thu Ha Thi} and Hudson-Smith, {Natalie V.} and Clement, {Peter L.} and Forester, {Dona Carla} and Hilena Frew and Hang, {Mimi N.} and Murphy, {Catherine J.} and Hamers, {Robert J.} and Feng, {Z. Vivian} and Haynes, {Christy L.}",
year = "2017",
month = "2",
day = "7",
doi = "10.1021/acs.analchem.6b04652",
language = "English (US)",
volume = "89",
pages = "2057--2064",
journal = "Analytical Chemistry",
issn = "0003-2700",
publisher = "American Chemical Society",
number = "3",

}

TY - JOUR

T1 - Growth-Based Bacterial Viability Assay for Interference-Free and High-Throughput Toxicity Screening of Nanomaterials

AU - Qiu, Tian A.

AU - Nguyen, Thu Ha Thi

AU - Hudson-Smith, Natalie V.

AU - Clement, Peter L.

AU - Forester, Dona Carla

AU - Frew, Hilena

AU - Hang, Mimi N.

AU - Murphy, Catherine J.

AU - Hamers, Robert J.

AU - Feng, Z. Vivian

AU - Haynes, Christy L.

PY - 2017/2/7

Y1 - 2017/2/7

N2 - Current high-throughput approaches evaluating toxicity of chemical agents toward bacteria typically rely on optical assays, such as luminescence and absorbance, to probe the viability of the bacteria. However, when applied to toxicity induced by nanomaterials, scattering and absorbance from the nanomaterials act as interferences that complicate quantitative analysis. Herein, we describe a bacterial viability assay that is free of optical interference from nanomaterials and can be performed in a high-throughput format on 96-well plates. In this assay, bacteria were exposed to various materials and then diluted by a large factor into fresh growth medium. The large dilution ensured minimal optical interference from the nanomaterial when reading optical density, and the residue left from the exposure mixture after dilution was confirmed not to impact the bacterial growth profile. The fractions of viable cells after exposure were allowed to grow in fresh medium to generate measurable growth curves. Bacterial viability was then quantitatively correlated to the delay of bacterial growth compared to a reference regarded as 100% viable cells; data analysis was inspired by that in quantitative polymerase chain reactions, where the delay in the amplification curve is correlated to the starting amount of the template nucleic acid. Fast and robust data analysis was achieved by developing computer algorithms carried out using R. This method was tested on four bacterial strains, including both Gram-negative and Gram-positive bacteria, showing great potential for application to all culturable bacterial strains. With the increasing diversity of engineered nanomaterials being considered for large-scale use, this high-throughput screening method will facilitate rapid screening of nanomaterial toxicity and thus inform the risk assessment of nanoparticles in a timely fashion.

AB - Current high-throughput approaches evaluating toxicity of chemical agents toward bacteria typically rely on optical assays, such as luminescence and absorbance, to probe the viability of the bacteria. However, when applied to toxicity induced by nanomaterials, scattering and absorbance from the nanomaterials act as interferences that complicate quantitative analysis. Herein, we describe a bacterial viability assay that is free of optical interference from nanomaterials and can be performed in a high-throughput format on 96-well plates. In this assay, bacteria were exposed to various materials and then diluted by a large factor into fresh growth medium. The large dilution ensured minimal optical interference from the nanomaterial when reading optical density, and the residue left from the exposure mixture after dilution was confirmed not to impact the bacterial growth profile. The fractions of viable cells after exposure were allowed to grow in fresh medium to generate measurable growth curves. Bacterial viability was then quantitatively correlated to the delay of bacterial growth compared to a reference regarded as 100% viable cells; data analysis was inspired by that in quantitative polymerase chain reactions, where the delay in the amplification curve is correlated to the starting amount of the template nucleic acid. Fast and robust data analysis was achieved by developing computer algorithms carried out using R. This method was tested on four bacterial strains, including both Gram-negative and Gram-positive bacteria, showing great potential for application to all culturable bacterial strains. With the increasing diversity of engineered nanomaterials being considered for large-scale use, this high-throughput screening method will facilitate rapid screening of nanomaterial toxicity and thus inform the risk assessment of nanoparticles in a timely fashion.

UR - http://www.scopus.com/inward/record.url?scp=85026782625&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85026782625&partnerID=8YFLogxK

U2 - 10.1021/acs.analchem.6b04652

DO - 10.1021/acs.analchem.6b04652

M3 - Article

C2 - 28208291

AN - SCOPUS:85026782625

VL - 89

SP - 2057

EP - 2064

JO - Analytical Chemistry

JF - Analytical Chemistry

SN - 0003-2700

IS - 3

ER -