Hydrophilization of Magnetic Nanoparticles with Modified Alternating Copolymers. Part 2: Behavior in solution.
Aqueous solutions of iron oxide nanoparticles (NPs) stabilized by poly(maleic acid-alt-1-octadecene) (PMAcOD) modified with the 5,000 Da poly(ethylene glycol) (PEG) or the short ethylene glycol (EG) tails were analyzed by small-angle X-ray scattering (SAXS). Advanced SAXS data analysis methods were employed to systematically characterize the structure and interactions between the NPs. Depending on the type of the grafted tail and the grafting density all NPs can be separated into three groups. All the samples contain mixtures of individual nanoparticles, their dynamic clusters and aggregates, and the fractions of these species are different in the different groups. The first group consists of NPs coated with PMAcOD modified with the long PEG tails with the maximal grafting density, and the content of dynamic clusters and aggregates in the samples of this group does not exceed 4%. The samples from the second group with less dense coatings demonstrate a larger amount (5-7%) of the aggregates and dynamic clusters. The samples from the third group consisting of the NPs protected by EG modified PMAcOD contain mostly individual NPs and some amount of dumbbell dimers without noticeable aggregation. Importantly, the solution behavior of the NPs is independent on the iron oxide core size. Our results therefore provide means of predicting stabilization and avoiding aggregation of NPs based on the type of a protective shell.
Institute of Crystallography, Russian Academy of Sciences, Leninsky pr. 59, 117333 Moscow, Russia.
Eleonora V
EV
Shtykova
Andrey
A
Malyutin
Jason
J
Dyke
Barry
B
Stein
Peter V
PV
Konarev
Bogdan
B
Dragnea
Dmitri I
DI
Svergun
Lyudmila M
LM
Bronstein
Nat Mater. 2004 Dec;3(12):891-5
15568032
Langmuir. 2008 May 20;24(10):5225-8
18429625
Mol Microbiol. 2009 Mar;71(5):1308-22
19183279
Langmuir. 2007 Apr 10;23(8):4296-302
17323988
Small. 2006 Oct;2(10):1203-11
17193590
J Phys Chem C Nanomater Interfaces. 2008;112(43):16809-16817
19194520
J Mater Chem. 2009 Jan 1;19(24):4231-4239
19763240
J Phys Chem B. 2005 Jul 7;109(26):12762-71
16852582
J Phys Chem C Nanomater Interfaces. 2010 Dec 23;114(50):21900-21907
21221425
Anal Chem. 2009 Jan 1;81(1):296-301
19117457
J Phys Chem B. 2005 Feb 3;109(4):1347-60
16851102
J Phys Chem B. 2004 May 20;108(20):6175-85
18950098
Biophys J. 1999 Jun;76(6):2879-86
10354416
Biophys J. 2005 Aug;89(2):1237-50
15923225
J Phys Chem B. 2006 Oct 5;110(39):19456-60
17004805
J Phys Chem B. 2005 Oct 13;109(40):18786-98
16853418
Biomaterials. 2010 Apr;31(12):3384-94
20149435