Helical Assembly of Flavin Mononucleotides on Carbon Nanotubes as Multimodal Near-IR Hg(II)-Selective Probes

Minsuk Park, Kyeong Im Hong, Seon Mi Jin, Eunji Lee, Woo Dong Jang, Sang Yong Ju

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The development of novel methods to detect mercury is of paramount importance owing to the impact of this metal on human health and the environment. We observed that flavin mononucleotide (FMN) and its helical assembly with a single-walled carbon nanotube (SWNT) selectively bind Hg 2+ arising from HgCl 2 and MeHgCl. Absorption spectroscopic studies show that FMN preferentially forms a 2:1 rather than a 1:1 complex with Hg 2+ at high FMN concentrations. On the basis of the analogy to the thymine-Hg-thymine complex, it is proposed that the 2:1 complex between FMN and Hg 2+ comprises a Hg-bridged pair of FMN groups, regardless of the presence of SWNT. Upon addition of as little as a few hundred nanomoles of Hg 2+ , both FMN and FMN-SWNT exhibit absorption and photoluminescence (PL) changes. Moreover, FMN-SWNT displays simultaneous multiple sigmoidal changes in PL of SWNT tubes having different chiral vectors. Assessment of binding affinities using the Hill equation suggests that 2:1 and 1:1 complexes form between Hg 2+ and FMN groups on the FMN-SWNT. Theoretical calculations indicate that optical changes of the FMN-SWNT originate from Hg-mediated conformational changes occurring on the helical array of FMN on the SWNT. High-resolution transmission electron microscopy revealed that the presence of Hg 2+ in complexes with the FMN-SWNT enables visualization of helical periodic undulation of FMN groups along SWNT without the need for staining. Circular dichroism (CD) study revealed that FMN-SWNT whose CD signal mainly originates from FMN decreases dichroic bands upon the addition of Hg 2+ owing to the formation of a centrosymmetric FMN-Hg-FMN triad on SWNT. The binding mode specificity and multimodal changes observed in response to Hg 2+ ions suggest that systems based on FMN-SWNT can serve as in vivo NIR beacons for the detection of various mercury derivatives.

Original languageEnglish
Pages (from-to)8400-8411
Number of pages12
JournalACS Applied Materials and Interfaces
Volume11
Issue number8
DOIs
Publication statusPublished - 2019 Feb 27

Fingerprint

Flavin Mononucleotide
Carbon Nanotubes
Single-walled carbon nanotubes (SWCN)
Carbon nanotubes
Dichroism
Photoluminescence
Thymine
Mercury
High resolution transmission electron microscopy

All Science Journal Classification (ASJC) codes

  • Materials Science(all)

Cite this

@article{5c979a4a9ca04e889cb86aba33e29df5,
title = "Helical Assembly of Flavin Mononucleotides on Carbon Nanotubes as Multimodal Near-IR Hg(II)-Selective Probes",
abstract = "The development of novel methods to detect mercury is of paramount importance owing to the impact of this metal on human health and the environment. We observed that flavin mononucleotide (FMN) and its helical assembly with a single-walled carbon nanotube (SWNT) selectively bind Hg 2+ arising from HgCl 2 and MeHgCl. Absorption spectroscopic studies show that FMN preferentially forms a 2:1 rather than a 1:1 complex with Hg 2+ at high FMN concentrations. On the basis of the analogy to the thymine-Hg-thymine complex, it is proposed that the 2:1 complex between FMN and Hg 2+ comprises a Hg-bridged pair of FMN groups, regardless of the presence of SWNT. Upon addition of as little as a few hundred nanomoles of Hg 2+ , both FMN and FMN-SWNT exhibit absorption and photoluminescence (PL) changes. Moreover, FMN-SWNT displays simultaneous multiple sigmoidal changes in PL of SWNT tubes having different chiral vectors. Assessment of binding affinities using the Hill equation suggests that 2:1 and 1:1 complexes form between Hg 2+ and FMN groups on the FMN-SWNT. Theoretical calculations indicate that optical changes of the FMN-SWNT originate from Hg-mediated conformational changes occurring on the helical array of FMN on the SWNT. High-resolution transmission electron microscopy revealed that the presence of Hg 2+ in complexes with the FMN-SWNT enables visualization of helical periodic undulation of FMN groups along SWNT without the need for staining. Circular dichroism (CD) study revealed that FMN-SWNT whose CD signal mainly originates from FMN decreases dichroic bands upon the addition of Hg 2+ owing to the formation of a centrosymmetric FMN-Hg-FMN triad on SWNT. The binding mode specificity and multimodal changes observed in response to Hg 2+ ions suggest that systems based on FMN-SWNT can serve as in vivo NIR beacons for the detection of various mercury derivatives.",
author = "Minsuk Park and Hong, {Kyeong Im} and Jin, {Seon Mi} and Eunji Lee and Jang, {Woo Dong} and Ju, {Sang Yong}",
year = "2019",
month = "2",
day = "27",
doi = "10.1021/acsami.8b18781",
language = "English",
volume = "11",
pages = "8400--8411",
journal = "ACS applied materials & interfaces",
issn = "1944-8244",
publisher = "American Chemical Society",
number = "8",

}

Helical Assembly of Flavin Mononucleotides on Carbon Nanotubes as Multimodal Near-IR Hg(II)-Selective Probes. / Park, Minsuk; Hong, Kyeong Im; Jin, Seon Mi; Lee, Eunji; Jang, Woo Dong; Ju, Sang Yong.

In: ACS Applied Materials and Interfaces, Vol. 11, No. 8, 27.02.2019, p. 8400-8411.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Helical Assembly of Flavin Mononucleotides on Carbon Nanotubes as Multimodal Near-IR Hg(II)-Selective Probes

AU - Park, Minsuk

AU - Hong, Kyeong Im

AU - Jin, Seon Mi

AU - Lee, Eunji

AU - Jang, Woo Dong

AU - Ju, Sang Yong

PY - 2019/2/27

Y1 - 2019/2/27

N2 - The development of novel methods to detect mercury is of paramount importance owing to the impact of this metal on human health and the environment. We observed that flavin mononucleotide (FMN) and its helical assembly with a single-walled carbon nanotube (SWNT) selectively bind Hg 2+ arising from HgCl 2 and MeHgCl. Absorption spectroscopic studies show that FMN preferentially forms a 2:1 rather than a 1:1 complex with Hg 2+ at high FMN concentrations. On the basis of the analogy to the thymine-Hg-thymine complex, it is proposed that the 2:1 complex between FMN and Hg 2+ comprises a Hg-bridged pair of FMN groups, regardless of the presence of SWNT. Upon addition of as little as a few hundred nanomoles of Hg 2+ , both FMN and FMN-SWNT exhibit absorption and photoluminescence (PL) changes. Moreover, FMN-SWNT displays simultaneous multiple sigmoidal changes in PL of SWNT tubes having different chiral vectors. Assessment of binding affinities using the Hill equation suggests that 2:1 and 1:1 complexes form between Hg 2+ and FMN groups on the FMN-SWNT. Theoretical calculations indicate that optical changes of the FMN-SWNT originate from Hg-mediated conformational changes occurring on the helical array of FMN on the SWNT. High-resolution transmission electron microscopy revealed that the presence of Hg 2+ in complexes with the FMN-SWNT enables visualization of helical periodic undulation of FMN groups along SWNT without the need for staining. Circular dichroism (CD) study revealed that FMN-SWNT whose CD signal mainly originates from FMN decreases dichroic bands upon the addition of Hg 2+ owing to the formation of a centrosymmetric FMN-Hg-FMN triad on SWNT. The binding mode specificity and multimodal changes observed in response to Hg 2+ ions suggest that systems based on FMN-SWNT can serve as in vivo NIR beacons for the detection of various mercury derivatives.

AB - The development of novel methods to detect mercury is of paramount importance owing to the impact of this metal on human health and the environment. We observed that flavin mononucleotide (FMN) and its helical assembly with a single-walled carbon nanotube (SWNT) selectively bind Hg 2+ arising from HgCl 2 and MeHgCl. Absorption spectroscopic studies show that FMN preferentially forms a 2:1 rather than a 1:1 complex with Hg 2+ at high FMN concentrations. On the basis of the analogy to the thymine-Hg-thymine complex, it is proposed that the 2:1 complex between FMN and Hg 2+ comprises a Hg-bridged pair of FMN groups, regardless of the presence of SWNT. Upon addition of as little as a few hundred nanomoles of Hg 2+ , both FMN and FMN-SWNT exhibit absorption and photoluminescence (PL) changes. Moreover, FMN-SWNT displays simultaneous multiple sigmoidal changes in PL of SWNT tubes having different chiral vectors. Assessment of binding affinities using the Hill equation suggests that 2:1 and 1:1 complexes form between Hg 2+ and FMN groups on the FMN-SWNT. Theoretical calculations indicate that optical changes of the FMN-SWNT originate from Hg-mediated conformational changes occurring on the helical array of FMN on the SWNT. High-resolution transmission electron microscopy revealed that the presence of Hg 2+ in complexes with the FMN-SWNT enables visualization of helical periodic undulation of FMN groups along SWNT without the need for staining. Circular dichroism (CD) study revealed that FMN-SWNT whose CD signal mainly originates from FMN decreases dichroic bands upon the addition of Hg 2+ owing to the formation of a centrosymmetric FMN-Hg-FMN triad on SWNT. The binding mode specificity and multimodal changes observed in response to Hg 2+ ions suggest that systems based on FMN-SWNT can serve as in vivo NIR beacons for the detection of various mercury derivatives.

UR - http://www.scopus.com/inward/record.url?scp=85062326081&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85062326081&partnerID=8YFLogxK

U2 - 10.1021/acsami.8b18781

DO - 10.1021/acsami.8b18781

M3 - Article

C2 - 30724070

AN - SCOPUS:85062326081

VL - 11

SP - 8400

EP - 8411

JO - ACS applied materials & interfaces

JF - ACS applied materials & interfaces

SN - 1944-8244

IS - 8

ER -