Hofmeister challenges: Ion binding and charge of the BSA protein as explicit examples

Luca Medda; Brajesh Barse; Francesca Cugia; Mathias Boström; Drew F. Parsons; Barry W. Ninham; Maura Monduzzi; Andrea Salis

doi:10.1021/la3035984

Hofmeister challenges: Ion binding and charge of the BSA protein as explicit examples

Luca Medda, Brajesh Barse, Francesca Cugia, Mathias Boström, Drew F. Parsons, Barry W. Ninham, Maura Monduzzi, Andrea Salis^*

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

85 Citations (Scopus)

Abstract

Experiments on bovine serum albumin (BSA) via potentiometric titration (PT) and electrophoretic light scattering (ELS) are used to study specific-ion binding. The effect is appreciable at a physiological concentration of 0.1 M. We found that anions bind to the protein surface at an acidic pH, where the protein carries a positive charge (Z_p > 0), according to a Hofmeister series (Cl^- < Br^- < NO₃ ^- < I^- < SCN^-), as well as at the isoionic point (Z_p = 0). The results obtained require critical interpretation. The measurements performed depend on electrostatic theories that ignore the very specific effects they are supposed to reveal. Notwithstanding this difficulty, we can still infer that different 1:1 sodium salts affect the BSA surface charge/pH curve because anions bind to the BSA surface with an efficiency which follows a Hofmeister series.

Original language	English
Pages (from-to)	16355-16363
Number of pages	9
Journal	Langmuir
Volume	28
Issue number	47
DOIs	https://doi.org/10.1021/la3035984
Publication status	Published - 27 Nov 2012

Access to Document

10.1021/la3035984

Cite this

@article{4c5de51e686140369f2fccfd2116cc86,

title = "Hofmeister challenges: Ion binding and charge of the BSA protein as explicit examples",

abstract = "Experiments on bovine serum albumin (BSA) via potentiometric titration (PT) and electrophoretic light scattering (ELS) are used to study specific-ion binding. The effect is appreciable at a physiological concentration of 0.1 M. We found that anions bind to the protein surface at an acidic pH, where the protein carries a positive charge (Zp > 0), according to a Hofmeister series (Cl- < Br- < NO3 - < I- < SCN-), as well as at the isoionic point (Zp = 0). The results obtained require critical interpretation. The measurements performed depend on electrostatic theories that ignore the very specific effects they are supposed to reveal. Notwithstanding this difficulty, we can still infer that different 1:1 sodium salts affect the BSA surface charge/pH curve because anions bind to the BSA surface with an efficiency which follows a Hofmeister series.",

author = "Luca Medda and Brajesh Barse and Francesca Cugia and Mathias Bostr{\"o}m and Parsons, {Drew F.} and Ninham, {Barry W.} and Maura Monduzzi and Andrea Salis",

year = "2012",

month = nov,

day = "27",

doi = "10.1021/la3035984",

language = "English",

volume = "28",

pages = "16355--16363",

journal = "Langmuir",

issn = "0743-7463",

publisher = "American Chemical Society",

number = "47",

}

TY - JOUR

T1 - Hofmeister challenges

T2 - Ion binding and charge of the BSA protein as explicit examples

AU - Medda, Luca

AU - Barse, Brajesh

AU - Cugia, Francesca

AU - Boström, Mathias

AU - Parsons, Drew F.

AU - Ninham, Barry W.

AU - Monduzzi, Maura

AU - Salis, Andrea

PY - 2012/11/27

Y1 - 2012/11/27

N2 - Experiments on bovine serum albumin (BSA) via potentiometric titration (PT) and electrophoretic light scattering (ELS) are used to study specific-ion binding. The effect is appreciable at a physiological concentration of 0.1 M. We found that anions bind to the protein surface at an acidic pH, where the protein carries a positive charge (Zp > 0), according to a Hofmeister series (Cl- < Br- < NO3 - < I- < SCN-), as well as at the isoionic point (Zp = 0). The results obtained require critical interpretation. The measurements performed depend on electrostatic theories that ignore the very specific effects they are supposed to reveal. Notwithstanding this difficulty, we can still infer that different 1:1 sodium salts affect the BSA surface charge/pH curve because anions bind to the BSA surface with an efficiency which follows a Hofmeister series.

AB - Experiments on bovine serum albumin (BSA) via potentiometric titration (PT) and electrophoretic light scattering (ELS) are used to study specific-ion binding. The effect is appreciable at a physiological concentration of 0.1 M. We found that anions bind to the protein surface at an acidic pH, where the protein carries a positive charge (Zp > 0), according to a Hofmeister series (Cl- < Br- < NO3 - < I- < SCN-), as well as at the isoionic point (Zp = 0). The results obtained require critical interpretation. The measurements performed depend on electrostatic theories that ignore the very specific effects they are supposed to reveal. Notwithstanding this difficulty, we can still infer that different 1:1 sodium salts affect the BSA surface charge/pH curve because anions bind to the BSA surface with an efficiency which follows a Hofmeister series.

UR - http://www.scopus.com/inward/record.url?scp=84870170136&partnerID=8YFLogxK

U2 - 10.1021/la3035984

DO - 10.1021/la3035984

M3 - Article

SN - 0743-7463

VL - 28

SP - 16355

EP - 16363

JO - Langmuir

JF - Langmuir

IS - 47

ER -

Hofmeister challenges: Ion binding and charge of the BSA protein as explicit examples

Abstract

Access to Document

Other files and links

Fingerprint

Cite this