Control of interfacial pH in mesoporous silica nanoparticles via surface functionalization

Singappuli-Arachchige, Dilini; Slowing, Igor I.

doi:10.1063/1.5138912

Title: Control of interfacial pH in mesoporous silica nanoparticles via surface functionalization

Abstract

The pH at silica-water interfaces (pH_int) was measured by grafting a dual emission fluorescent probe (SNARF) onto the surface of mesoporous silica nanoparticles (MSN). The values of pH_int of SNARF-MSN suspended in water were different from the pH of the bulk solution (pH_bulk). The addition of acid or base to aqueous suspensions of SNARF-MSN induced much larger changes in pH_bulk than pH_int, indicating that the interface has buffering capacity. Grafting additional organic functional groups onto the surface of SNARF-MSN controls the pH_int of its buffering region. The responses of pH_int to variations in pH_bulk are consistent with the acid/base properties of the surface groups as determined by their pK_a and are affected by electrostatic interactions between charged interfacial species as evidenced by the dependence of ζ-potential on pH_bulk. Finally, as a proof of principle, we demonstrate that the hydrolysis rate of an acid-sensitive acetal can be controlled by adjusting pH_int via suitable functionalization of the MSN surface. Our findings can lead to the development of nanoreactors that protect sensitive species from adverse conditions and tune their chemical reactivity.

Authors:

^[1];

^[1]

Ames Lab., Ames, IA (United States); Iowa State Univ., Ames, IA (United States)

Publication Date:: 2020-01-16

Research Org.:: Ames Lab., Ames, IA (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1594062

Alternate Identifier(s):: OSTI ID: 1591968

Report Number(s):: IS-J-10118
Journal ID: ISSN 0021-9606; TRN: US2100786

Grant/Contract Number:: AC02-07CH11358

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Chemical Physics

Additional Journal Information:: Journal Volume: 152; Journal Issue: 3; Journal ID: ISSN 0021-9606

Publisher:: American Institute of Physics (AIP)

Country of Publication:: United States

Language:: English

Subject:: 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats


                    Singappuli-Arachchige, Dilini, and Slowing, Igor I. Control of interfacial pH in mesoporous silica nanoparticles via surface functionalization.  United States: N. p., 2020. 
Web.  doi:10.1063/1.5138912.

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                    Singappuli-Arachchige, Dilini, & Slowing, Igor I. Control of interfacial pH in mesoporous silica nanoparticles via surface functionalization.  United States.  https://doi.org/10.1063/1.5138912

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                    Singappuli-Arachchige, Dilini, and Slowing, Igor I. Thu .  
"Control of interfacial pH in mesoporous silica nanoparticles via surface functionalization".  United States.  https://doi.org/10.1063/1.5138912.  https://www.osti.gov/servlets/purl/1594062.

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@article{osti_1594062,

  title        = {Control of interfacial pH in mesoporous silica nanoparticles via surface functionalization},

  author       = {Singappuli-Arachchige, Dilini and Slowing, Igor I.},

  abstractNote = {The pH at silica-water interfaces (pHint) was measured by grafting a dual emission fluorescent probe (SNARF) onto the surface of mesoporous silica nanoparticles (MSN). The values of pHint of SNARF-MSN suspended in water were different from the pH of the bulk solution (pHbulk). The addition of acid or base to aqueous suspensions of SNARF-MSN induced much larger changes in pHbulk than pHint, indicating that the interface has buffering capacity. Grafting additional organic functional groups onto the surface of SNARF-MSN controls the pHint of its buffering region. The responses of pHint to variations in pHbulk are consistent with the acid/base properties of the surface groups as determined by their pKa and are affected by electrostatic interactions between charged interfacial species as evidenced by the dependence of ζ-potential on pHbulk. Finally, as a proof of principle, we demonstrate that the hydrolysis rate of an acid-sensitive acetal can be controlled by adjusting pHint via suitable functionalization of the MSN surface. Our findings can lead to the development of nanoreactors that protect sensitive species from adverse conditions and tune their chemical reactivity.},

  doi          = {10.1063/1.5138912},

  journal      = {Journal of Chemical Physics},

  number       = 3,

  volume       = 152,

  place        = {United States},

  year         = {2020},

  month        = {1}

}

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Title: Control of interfacial pH in mesoporous silica nanoparticles via surface functionalization

Abstract

Citation Formats

Effect of Surface Polarity on Water Contact Angle and Interfacial Hydration Structure journal, August 2007

Surface solvation and hindered isomerization at the water/silica interface explored with second harmonic generation journal, May 2019

Dynamics of pH-sensitive nitroxide radicals in water adsorbed in ordered mesoporous molecular sieves by EPR Spectroscopy journal, September 2013

Size dependent surface charge properties of silica nano-channels: double layer overlap and inlet/outlet effects journal, January 2018

Design considerations for mesoporous silica nanoparticulate systems in facilitating biomedical applications journal, January 2014

Fine-tuning the release of molecular guests from mesoporous silicas by controlling the orientation and mobility of surface phenyl substituents journal, May 2018

Bare and Effective Charge of Mesoporous Silica Particles journal, July 2017

Impact of seawater acidification on pH at the tissue-skeleton interface and calcification in reef corals journal, December 2012

On the Nature of the Brønsted Acidic Groups on Native and Functionalized Mesoporous Siliceous SBA-15 as Studied by Benzylamine Adsorption from Solution journal, April 2007

Synthesis and characterization of pH sensitive carboxySNARF-1 nanoreactors journal, April 2010

Solid-State NMR Study of MCM-41-type Mesoporous Silica Nanoparticles journal, March 2005

Internal surface electric charge characterization of mesoporous silica journal, January 2019

Protonation Constants of Ethylenediamine, Diethylenetriamine, and Spermine in NaCl(aq), NaI(aq), (CH 3 ) 4 NCl(aq) , and (C 2 H 5 ) 4 NI(aq) at Different Ionic Strengths and t = 25 °C journal, November 2005

Pyridine- 15 N A Mobile NMR Sensor for Surface Acidity and Surface Defects of Mesoporous Silica journal, October 2003

Amide bands in the IR spectra of urethanes journal, November 2009

Effect of Surface Hydrophilicity on the Interfacial Properties of a Model Octane–Water–Silica System journal, July 2019

Ionic Specificity in pH Regulated Charged Interfaces: Fe 3+ versus La 3+ journal, October 2011

Ultra-small mesoporous silica nanoparticles as efficient carriers for pH responsive releases of anti-cancer drugs journal, January 2015

Vibrational spectra of water at water/α-quartz (0001) interface journal, March 2004

Enhancement of Proton Transport by High Densification of Sulfonic Acid Groups in Highly Ordered Mesoporous Silica journal, April 2013

Acid−Base Equilibria inside Amine-Functionalized Mesoporous Silica journal, April 2011

Elucidating the Bimodal Acid−Base Behavior of the Water−Silica Interface from First Principles journal, December 2009

Polarity Control at Interfaces: Quantifying Pseudo-solvent Effects in Nano-confined Systems journal, August 2016

Electrical potential near hydrated surface of ordered mesoporous molecular sieves assessed by EPR of molecular pH-probes journal, February 2015

Molecular Dynamics of Ionic Transport and Electrokinetic Effects in Realistic Silica Channels journal, June 2008

Interfacial Control of Catalytic Activity in the Aldol Condensation: Combining the Effects of Hydrophobic Environments and Water journal, May 2019

Amino Acid Adsorption on Mesoporous Materials: Influence of Types of Amino Acids, Modification of Mesoporous Materials, and Solution Conditions journal, February 2008

Ion-Permselective pH-Switchable Mesoporous Silica Thin Layers journal, April 2007

Interfacial pH at an Isolated Silica−Water Surface journal, February 2005

Proton Activity in Nanochannels Revealed by Electron Paramagnetic Resonance of Ionizable Nitroxides: A Test of the Poisson–Boltzmann Double Layer Theory journal, August 2018

Detection of Local Density Distribution of Isolated Silanol Groups on Planar Silica Surfaces Using Nonlinear Optical Molecular Probes journal, November 1998

Carboxyl group participation in acetal hydrolysis. Hydrolysis of disalicyl acetals journal, September 1973

Probing the proton excess at interfaces by second harmonic generation journal, November 1989

Polarization of water molecules at a charged interface: second harmonic studies of the silica/water interface journal, April 1992

Spatial arrangement and acid strength effects on acid–base cooperatively catalyzed aldol condensation on aminosilica materials journal, May 2015

Tuning acid–base cooperativity to create next generation silica-supported organocatalysts journal, December 2013

The role of water in the reusability of aminated silica catalysts for aldol reactions journal, May 2018

Debye Length in Multivalent Electrolyte Solutions journal, June 2000

A method to measure pH inside mesoporous particles using protein-bound SNARF1 fluorescent probe journal, January 2013

Elucidating the Bimodal Acid-base Behavior of the Water-silica Interface from First Principles text, January 2010

Effect of Surface Polarity on Water Contact Angle and Interfacial Hydration Structure
journal, August 2007

Surface solvation and hindered isomerization at the water/silica interface explored with second harmonic generation
journal, May 2019

Dynamics of pH-sensitive nitroxide radicals in water adsorbed in ordered mesoporous molecular sieves by EPR Spectroscopy
journal, September 2013

Size dependent surface charge properties of silica nano-channels: double layer overlap and inlet/outlet effects
journal, January 2018

Design considerations for mesoporous silica nanoparticulate systems in facilitating biomedical applications
journal, January 2014

Fine-tuning the release of molecular guests from mesoporous silicas by controlling the orientation and mobility of surface phenyl substituents
journal, May 2018

Bare and Effective Charge of Mesoporous Silica Particles
journal, July 2017

Impact of seawater acidification on pH at the tissue-skeleton interface and calcification in reef corals
journal, December 2012

On the Nature of the Brønsted Acidic Groups on Native and Functionalized Mesoporous Siliceous SBA-15 as Studied by Benzylamine Adsorption from Solution
journal, April 2007

Synthesis and characterization of pH sensitive carboxySNARF-1 nanoreactors
journal, April 2010

Solid-State NMR Study of MCM-41-type Mesoporous Silica Nanoparticles
journal, March 2005

Internal surface electric charge characterization of mesoporous silica
journal, January 2019

Protonation Constants of Ethylenediamine, Diethylenetriamine, and Spermine in NaCl(aq), NaI(aq), (CH 3 ) 4 NCl(aq) , and (C 2 H 5 ) 4 NI(aq) at Different Ionic Strengths and t = 25 °C
journal, November 2005

Pyridine- ¹⁵ N A Mobile NMR Sensor for Surface Acidity and Surface Defects of Mesoporous Silica
journal, October 2003

Amide bands in the IR spectra of urethanes
journal, November 2009

Effect of Surface Hydrophilicity on the Interfacial Properties of a Model Octane–Water–Silica System
journal, July 2019

Ionic Specificity in pH Regulated Charged Interfaces: Fe 3+ versus La 3+
journal, October 2011

Ultra-small mesoporous silica nanoparticles as efficient carriers for pH responsive releases of anti-cancer drugs
journal, January 2015

Vibrational spectra of water at water/α-quartz (0001) interface
journal, March 2004

Enhancement of Proton Transport by High Densification of Sulfonic Acid Groups in Highly Ordered Mesoporous Silica
journal, April 2013

Acid−Base Equilibria inside Amine-Functionalized Mesoporous Silica
journal, April 2011

Elucidating the Bimodal Acid−Base Behavior of the Water−Silica Interface from First Principles
journal, December 2009

Polarity Control at Interfaces: Quantifying Pseudo-solvent Effects in Nano-confined Systems
journal, August 2016

Electrical potential near hydrated surface of ordered mesoporous molecular sieves assessed by EPR of molecular pH-probes
journal, February 2015

Molecular Dynamics of Ionic Transport and Electrokinetic Effects in Realistic Silica Channels
journal, June 2008

Interfacial Control of Catalytic Activity in the Aldol Condensation: Combining the Effects of Hydrophobic Environments and Water
journal, May 2019

Amino Acid Adsorption on Mesoporous Materials: Influence of Types of Amino Acids, Modification of Mesoporous Materials, and Solution Conditions
journal, February 2008

Ion-Permselective pH-Switchable Mesoporous Silica Thin Layers
journal, April 2007

Interfacial pH at an Isolated Silica−Water Surface
journal, February 2005

Proton Activity in Nanochannels Revealed by Electron Paramagnetic Resonance of Ionizable Nitroxides: A Test of the Poisson–Boltzmann Double Layer Theory
journal, August 2018

Detection of Local Density Distribution of Isolated Silanol Groups on Planar Silica Surfaces Using Nonlinear Optical Molecular Probes
journal, November 1998

Carboxyl group participation in acetal hydrolysis. Hydrolysis of disalicyl acetals
journal, September 1973

Probing the proton excess at interfaces by second harmonic generation
journal, November 1989

Polarization of water molecules at a charged interface: second harmonic studies of the silica/water interface
journal, April 1992

Spatial arrangement and acid strength effects on acid–base cooperatively catalyzed aldol condensation on aminosilica materials
journal, May 2015

Tuning acid–base cooperativity to create next generation silica-supported organocatalysts
journal, December 2013

The role of water in the reusability of aminated silica catalysts for aldol reactions
journal, May 2018

Debye Length in Multivalent Electrolyte Solutions
journal, June 2000

A method to measure pH inside mesoporous particles using protein-bound SNARF1 fluorescent probe
journal, January 2013

Elucidating the Bimodal Acid-base Behavior of the Water-silica Interface from First Principles
text, January 2010