ATR-FTIR study of lipopolysaccharides at mineral surfaces

Sanjai J. Parikh, Jon Chorover

Research output: Contribution to journalArticle

30 Citations (Scopus)

Abstract

Lipopolysaccharides (LPS) are ubiquitous in natural aqueous systems because of bacterial cell turnover and lysis. LPS sorption and conformation at the mineral/water interface are strongly influenced by both solution and surface chemistry. In this study, the interaction of LPS with various surfaces (ZnSe, GeO2, α-Fe2O3, α-Al2O3) that vary in surface charge and hydrophobicity was investigated using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. The presence of Ca2+ (versus Na+) in LPS solutions resulted in aggregate reorientation and increased sorptive retention. ATR-FTIR spectra of Na-LPS systems are consistent with reduced surface affinity and are similar to those of solution phase LPS. Ca-LPS spectra reveal hydrophobic interactions of the lipid A region at the ZnSe internal reflection element (IRE). However, pH-dependent charge controls Ca-LPS sorption to hydrophilic surfaces (GeO2, α-Fe2O3, and α-Al2O3), where bonding occurs principally via O-antigen functional groups. As a result of accumulation at the solid-liquid interface, spectra of Ca-LPS represent primarily surface-bound LPS. Variable-angle ATR-FTIR spectra of Ca-LPS systems show depth-dependent trends that occur at the spatial scale of LPS aggregates, consistent with the formation of vesicular structures.

Original languageEnglish (US)
Pages (from-to)188-198
Number of pages11
JournalColloids and Surfaces B: Biointerfaces
Volume62
Issue number2
DOIs
StatePublished - Apr 1 2008

Fingerprint

Fourier Analysis
Minerals
Lipopolysaccharides
Fourier transforms
minerals
Infrared radiation
reflectance
Sorption
sorption
infrared spectra
Antigens
Surface charge
Hydrophobicity
Surface chemistry
Lipids
Functional groups
Fourier transform infrared spectroscopy
Conformations
antigens
liquid-solid interfaces

Keywords

  • ATR-FTIR spectroscopy
  • Depth profiling
  • Endotoxins
  • LPS

ASJC Scopus subject areas

  • Biotechnology
  • Colloid and Surface Chemistry
  • Physical and Theoretical Chemistry
  • Surfaces and Interfaces

Cite this

ATR-FTIR study of lipopolysaccharides at mineral surfaces. / Parikh, Sanjai J.; Chorover, Jon.

In: Colloids and Surfaces B: Biointerfaces, Vol. 62, No. 2, 01.04.2008, p. 188-198.

Research output: Contribution to journalArticle

@article{e2206889de8e4214aead1cfd96b7b515,
title = "ATR-FTIR study of lipopolysaccharides at mineral surfaces",
abstract = "Lipopolysaccharides (LPS) are ubiquitous in natural aqueous systems because of bacterial cell turnover and lysis. LPS sorption and conformation at the mineral/water interface are strongly influenced by both solution and surface chemistry. In this study, the interaction of LPS with various surfaces (ZnSe, GeO2, α-Fe2O3, α-Al2O3) that vary in surface charge and hydrophobicity was investigated using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. The presence of Ca2+ (versus Na+) in LPS solutions resulted in aggregate reorientation and increased sorptive retention. ATR-FTIR spectra of Na-LPS systems are consistent with reduced surface affinity and are similar to those of solution phase LPS. Ca-LPS spectra reveal hydrophobic interactions of the lipid A region at the ZnSe internal reflection element (IRE). However, pH-dependent charge controls Ca-LPS sorption to hydrophilic surfaces (GeO2, α-Fe2O3, and α-Al2O3), where bonding occurs principally via O-antigen functional groups. As a result of accumulation at the solid-liquid interface, spectra of Ca-LPS represent primarily surface-bound LPS. Variable-angle ATR-FTIR spectra of Ca-LPS systems show depth-dependent trends that occur at the spatial scale of LPS aggregates, consistent with the formation of vesicular structures.",
keywords = "ATR-FTIR spectroscopy, Depth profiling, Endotoxins, LPS",
author = "Parikh, {Sanjai J.} and Jon Chorover",
year = "2008",
month = "4",
day = "1",
doi = "10.1016/j.colsurfb.2007.10.002",
language = "English (US)",
volume = "62",
pages = "188--198",
journal = "Colloids and Surfaces B: Biointerfaces",
issn = "0927-7765",
publisher = "Elsevier",
number = "2",

}

TY - JOUR

T1 - ATR-FTIR study of lipopolysaccharides at mineral surfaces

AU - Parikh, Sanjai J.

AU - Chorover, Jon

PY - 2008/4/1

Y1 - 2008/4/1

N2 - Lipopolysaccharides (LPS) are ubiquitous in natural aqueous systems because of bacterial cell turnover and lysis. LPS sorption and conformation at the mineral/water interface are strongly influenced by both solution and surface chemistry. In this study, the interaction of LPS with various surfaces (ZnSe, GeO2, α-Fe2O3, α-Al2O3) that vary in surface charge and hydrophobicity was investigated using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. The presence of Ca2+ (versus Na+) in LPS solutions resulted in aggregate reorientation and increased sorptive retention. ATR-FTIR spectra of Na-LPS systems are consistent with reduced surface affinity and are similar to those of solution phase LPS. Ca-LPS spectra reveal hydrophobic interactions of the lipid A region at the ZnSe internal reflection element (IRE). However, pH-dependent charge controls Ca-LPS sorption to hydrophilic surfaces (GeO2, α-Fe2O3, and α-Al2O3), where bonding occurs principally via O-antigen functional groups. As a result of accumulation at the solid-liquid interface, spectra of Ca-LPS represent primarily surface-bound LPS. Variable-angle ATR-FTIR spectra of Ca-LPS systems show depth-dependent trends that occur at the spatial scale of LPS aggregates, consistent with the formation of vesicular structures.

AB - Lipopolysaccharides (LPS) are ubiquitous in natural aqueous systems because of bacterial cell turnover and lysis. LPS sorption and conformation at the mineral/water interface are strongly influenced by both solution and surface chemistry. In this study, the interaction of LPS with various surfaces (ZnSe, GeO2, α-Fe2O3, α-Al2O3) that vary in surface charge and hydrophobicity was investigated using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. The presence of Ca2+ (versus Na+) in LPS solutions resulted in aggregate reorientation and increased sorptive retention. ATR-FTIR spectra of Na-LPS systems are consistent with reduced surface affinity and are similar to those of solution phase LPS. Ca-LPS spectra reveal hydrophobic interactions of the lipid A region at the ZnSe internal reflection element (IRE). However, pH-dependent charge controls Ca-LPS sorption to hydrophilic surfaces (GeO2, α-Fe2O3, and α-Al2O3), where bonding occurs principally via O-antigen functional groups. As a result of accumulation at the solid-liquid interface, spectra of Ca-LPS represent primarily surface-bound LPS. Variable-angle ATR-FTIR spectra of Ca-LPS systems show depth-dependent trends that occur at the spatial scale of LPS aggregates, consistent with the formation of vesicular structures.

KW - ATR-FTIR spectroscopy

KW - Depth profiling

KW - Endotoxins

KW - LPS

UR - http://www.scopus.com/inward/record.url?scp=39449121925&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=39449121925&partnerID=8YFLogxK

U2 - 10.1016/j.colsurfb.2007.10.002

DO - 10.1016/j.colsurfb.2007.10.002

M3 - Article

C2 - 18006288

AN - SCOPUS:39449121925

VL - 62

SP - 188

EP - 198

JO - Colloids and Surfaces B: Biointerfaces

JF - Colloids and Surfaces B: Biointerfaces

SN - 0927-7765

IS - 2

ER -