Unusual Salt Stability in Highly Charged Diblock Co-polypeptide Hydrogels

Andrew P. Nowak, Victor Breedveld, David J. Pine, Timothy J. Deming

Research output: Contribution to journalArticle

Abstract

The stability and properties of dilute solution hydrogels, synthesized by transition metal mediated polymerization of amino acid N-carboxyanhydrides (NCAs), have been studied in deionized (DI) water as well as various ionic media. These hydrogels are diblock amphiphilic copolymers of hydrophilic, charged segments of poly(L-lysine HBr) or poly(L-glutamic acid sodium salt), and helical, hydrophobic segments of poly(L-leucine). While many of these samples are able to form strong gels in deionized water at polymer concentrations as low as 0.25 wt %, stability in salt or buffer solutions was found to be only achieved at moderately higher polymer concentrations (∼3.0 wt %). We have adjusted relative copolymer compositions and molecular weights to optimize hydrogel strength and polymer solubility in salt concentrations up to 0.5 M NaCl, as well as in cell growth media and aqueous buffers of varying pH. These materials are unique since they do not collapse in high ionic strength media, even though gel formation is contingent upon the presence of highly charged polyelectrolyte segments. The remarkable properties of these hydrogels make them excellent candidates for use as scaffolds in biomedical applications, such as tissue regeneration.

Original languageEnglish (US)
Pages (from-to)15666-15670
Number of pages5
JournalJournal of the American Chemical Society
Volume125
Issue number50
DOIs
StatePublished - Dec 17 2003

Fingerprint

Hydrogels
Polypeptides
Polymers
Salts
Deionized water
Peptides
Buffers
Gels
Tissue regeneration
Water
Hydrogel
Cell growth
Ionic strength
Polyelectrolytes
Scaffolds
Polymerization
Osmolar Concentration
Solubility
Lysine
Block copolymers

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Unusual Salt Stability in Highly Charged Diblock Co-polypeptide Hydrogels. / Nowak, Andrew P.; Breedveld, Victor; Pine, David J.; Deming, Timothy J.

In: Journal of the American Chemical Society, Vol. 125, No. 50, 17.12.2003, p. 15666-15670.

Research output: Contribution to journalArticle

Nowak, Andrew P. ; Breedveld, Victor ; Pine, David J. ; Deming, Timothy J. / Unusual Salt Stability in Highly Charged Diblock Co-polypeptide Hydrogels. In: Journal of the American Chemical Society. 2003 ; Vol. 125, No. 50. pp. 15666-15670.
@article{f9918f87c58b48a99d7e96a933e22fcf,
title = "Unusual Salt Stability in Highly Charged Diblock Co-polypeptide Hydrogels",
abstract = "The stability and properties of dilute solution hydrogels, synthesized by transition metal mediated polymerization of amino acid N-carboxyanhydrides (NCAs), have been studied in deionized (DI) water as well as various ionic media. These hydrogels are diblock amphiphilic copolymers of hydrophilic, charged segments of poly(L-lysine HBr) or poly(L-glutamic acid sodium salt), and helical, hydrophobic segments of poly(L-leucine). While many of these samples are able to form strong gels in deionized water at polymer concentrations as low as 0.25 wt {\%}, stability in salt or buffer solutions was found to be only achieved at moderately higher polymer concentrations (∼3.0 wt {\%}). We have adjusted relative copolymer compositions and molecular weights to optimize hydrogel strength and polymer solubility in salt concentrations up to 0.5 M NaCl, as well as in cell growth media and aqueous buffers of varying pH. These materials are unique since they do not collapse in high ionic strength media, even though gel formation is contingent upon the presence of highly charged polyelectrolyte segments. The remarkable properties of these hydrogels make them excellent candidates for use as scaffolds in biomedical applications, such as tissue regeneration.",
author = "Nowak, {Andrew P.} and Victor Breedveld and Pine, {David J.} and Deming, {Timothy J.}",
year = "2003",
month = "12",
day = "17",
doi = "10.1021/ja0381050",
language = "English (US)",
volume = "125",
pages = "15666--15670",
journal = "Journal of the American Chemical Society",
issn = "0002-7863",
publisher = "American Chemical Society",
number = "50",

}

TY - JOUR

T1 - Unusual Salt Stability in Highly Charged Diblock Co-polypeptide Hydrogels

AU - Nowak, Andrew P.

AU - Breedveld, Victor

AU - Pine, David J.

AU - Deming, Timothy J.

PY - 2003/12/17

Y1 - 2003/12/17

N2 - The stability and properties of dilute solution hydrogels, synthesized by transition metal mediated polymerization of amino acid N-carboxyanhydrides (NCAs), have been studied in deionized (DI) water as well as various ionic media. These hydrogels are diblock amphiphilic copolymers of hydrophilic, charged segments of poly(L-lysine HBr) or poly(L-glutamic acid sodium salt), and helical, hydrophobic segments of poly(L-leucine). While many of these samples are able to form strong gels in deionized water at polymer concentrations as low as 0.25 wt %, stability in salt or buffer solutions was found to be only achieved at moderately higher polymer concentrations (∼3.0 wt %). We have adjusted relative copolymer compositions and molecular weights to optimize hydrogel strength and polymer solubility in salt concentrations up to 0.5 M NaCl, as well as in cell growth media and aqueous buffers of varying pH. These materials are unique since they do not collapse in high ionic strength media, even though gel formation is contingent upon the presence of highly charged polyelectrolyte segments. The remarkable properties of these hydrogels make them excellent candidates for use as scaffolds in biomedical applications, such as tissue regeneration.

AB - The stability and properties of dilute solution hydrogels, synthesized by transition metal mediated polymerization of amino acid N-carboxyanhydrides (NCAs), have been studied in deionized (DI) water as well as various ionic media. These hydrogels are diblock amphiphilic copolymers of hydrophilic, charged segments of poly(L-lysine HBr) or poly(L-glutamic acid sodium salt), and helical, hydrophobic segments of poly(L-leucine). While many of these samples are able to form strong gels in deionized water at polymer concentrations as low as 0.25 wt %, stability in salt or buffer solutions was found to be only achieved at moderately higher polymer concentrations (∼3.0 wt %). We have adjusted relative copolymer compositions and molecular weights to optimize hydrogel strength and polymer solubility in salt concentrations up to 0.5 M NaCl, as well as in cell growth media and aqueous buffers of varying pH. These materials are unique since they do not collapse in high ionic strength media, even though gel formation is contingent upon the presence of highly charged polyelectrolyte segments. The remarkable properties of these hydrogels make them excellent candidates for use as scaffolds in biomedical applications, such as tissue regeneration.

UR - http://www.scopus.com/inward/record.url?scp=0346219435&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0346219435&partnerID=8YFLogxK

U2 - 10.1021/ja0381050

DO - 10.1021/ja0381050

M3 - Article

VL - 125

SP - 15666

EP - 15670

JO - Journal of the American Chemical Society

JF - Journal of the American Chemical Society

SN - 0002-7863

IS - 50

ER -