PMID- 31145393
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20190613
IS  - 1463-9084 (Electronic)
IS  - 1463-9076 (Linking)
VI  - 21
IP  - 23
DP  - 2019 Jun 21
TI  - Block copolymers as bile salt sequestrants: intriguing structures formed in a 
      mixture of an oppositely charged amphiphilic block copolymer and bile salt.
PG  - 12518-12529
LID - 10.1039/c9cp01744e [doi]
AB  - To study the formation and characterize the structure of mixed complexes of 
      oppositely charged block copolymers and surfactants are of great significance for 
      practical applications, e.g., in drug carrier formulations that are based on 
      electrostatically assisted assembly. In this context, biocompatible block 
      copolymers and biosurfactants (like bile salts) are particularly interesting. In 
      this work, we report on the co-assembly in dilute aqueous solution between a 
      cationic poly(N-isopropyl acryl amide) (PNIPAM) diblock copolymer and the 
      oppositely charged bile salt surfactant sodium deoxycholate at ambient 
      temperature. The cryogenic transmission electron microscopy (cryo-TEM) 
      experiments revealed the co-existence of two types of co-assembled complexes of 
      radically different morphology and inner structure. They are formed mainly as a 
      result of the electrostatic attraction between the positively charged copolymer 
      blocks and bile salt anions and highlight the potential of using linear 
      amphiphilic block copolymers as bile salt sequestrants in the treatment of bile 
      acid malabsorption and hypercholesterolemia. The first complex of globular 
      morphology has a coacervate core of deoxycholate anions and charged copolymer 
      blocks surrounded by a PNIPAM corona. The second complex has an intriguing 
      tape-like supramolecular morphology of several micrometer in length that is 
      striped in the direction of the long axis. A model is presented in which the 
      stretched cationic blocks of several block copolymers interact electrostatically 
      with the bile salt molecules that are associated to form a zipper-like structure. 
      The tape is covered on both sides by the PNIPAM chains that stabilize the overall 
      complex in solution. In addition to cryo-TEM, the mixed system was investigated 
      in a range of molar charge fractions at a constant copolymer concentration by 
      static light scattering, small angle X-ray scattering, and electrophoretic 
      mobility measurements.
FAU - Schillen, Karin
AU  - Schillen K
AUID- ORCID: 0000-0001-8147-1733
AD  - Division of Physical Chemistry, Department of Chemistry, Lund University, P.O. 
      Box 124, SE-221 00 Lund, Sweden. Karin.Schillen@fkem1.lu.se.
FAU - Galantini, Luciano
AU  - Galantini L
AUID- ORCID: 0000-0001-5484-2658
AD  - Department of Chemistry, Sapienza University of Rome, P.O. Box 34-Roma 62, 
      Piazzale A. Moro 5, I-00185 Roma, Italy. luciano.galantini@uniroma1.it.
FAU - Du, Guanqun
AU  - Du G
AD  - Division of Physical Chemistry, Department of Chemistry, Lund University, P.O. 
      Box 124, SE-221 00 Lund, Sweden. Karin.Schillen@fkem1.lu.se.
FAU - Del Giudice, Alessandra
AU  - Del Giudice A
AUID- ORCID: 0000-0002-1916-8300
AD  - Department of Chemistry, Sapienza University of Rome, P.O. Box 34-Roma 62, 
      Piazzale A. Moro 5, I-00185 Roma, Italy. luciano.galantini@uniroma1.it.
FAU - Alfredsson, Viveka
AU  - Alfredsson V
AUID- ORCID: 0000-0002-9733-2735
AD  - Division of Physical Chemistry, Department of Chemistry, Lund University, P.O. 
      Box 124, SE-221 00 Lund, Sweden. Karin.Schillen@fkem1.lu.se.
FAU - Carnerup, Anna M
AU  - Carnerup AM
AD  - Division of Physical Chemistry, Department of Chemistry, Lund University, P.O. 
      Box 124, SE-221 00 Lund, Sweden. Karin.Schillen@fkem1.lu.se.
FAU - Pavel, Nicolae V
AU  - Pavel NV
AUID- ORCID: 0000-0002-7637-4821
AD  - Department of Chemistry, Sapienza University of Rome, P.O. Box 34-Roma 62, 
      Piazzale A. Moro 5, I-00185 Roma, Italy. luciano.galantini@uniroma1.it.
FAU - Masci, Giancarlo
AU  - Masci G
AUID- ORCID: 0000-0002-7213-8311
AD  - Department of Chemistry, Sapienza University of Rome, P.O. Box 34-Roma 62, 
      Piazzale A. Moro 5, I-00185 Roma, Italy. luciano.galantini@uniroma1.it.
FAU - Nystrom, Bo
AU  - Nystrom B
AD  - Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern N-0315, 
      Oslo, Norway.
LA  - eng
PT  - Journal Article
DEP - 20190530
PL  - England
TA  - Phys Chem Chem Phys
JT  - Physical chemistry chemical physics : PCCP
JID - 100888160
EDAT- 2019/05/31 06:00
MHDA- 2019/05/31 06:01
CRDT- 2019/05/31 06:00
PHST- 2019/05/31 06:00 [pubmed]
PHST- 2019/05/31 06:01 [medline]
PHST- 2019/05/31 06:00 [entrez]
AID - 10.1039/c9cp01744e [doi]
PST - ppublish
SO  - Phys Chem Chem Phys. 2019 Jun 21;21(23):12518-12529. doi: 10.1039/c9cp01744e. 
      Epub 2019 May 30.