Self-assembly of Block and Graft Copolymers in Aerosol Nanoparticles

Antti Rahikkala

Self-assembly of Block and Graft Copolymers in Aerosol Nanoparticles

Julkaisun otsikon käännös: Lohko- ja oksastettujen polymeerien itsejärjestyminen aerosolinanohiukkasissa

Antti Rahikkala

Teknillisen fysiikan laitos

Tutkimustuotos: Doctoral Thesis › Collection of Articles

Abstrakti

Tämän väitöskirjan tarkoitus oli tutkia lohko- ja oksastettujen kopolymeerien itsejärjestymistä nanohiukkasissa faasierottuneisiin, mitoiltaan 3-30 nm paksuihin sisärakenteisiin, kun hiukkaset tuotetaan aerosolivirtausreaktoritekniikalla. Väitöskirjassa tutkittiin myös nanohiukkasten soveltuvuutta lääkkeenkuljetukseen. Lohkopolymeerit koostuvat kahdesta tai useammasta kemiallisesti erilaisesta polymeeristä, jotka on kovalenttisesti sidottu toisiinsa. Oksastetuissa kopolymeereissä molekyylejä on kiinnitetty sivuketjuina pääketjuun. Kopolymeerien eri osien väliset kemialliset erot johtavat faasierottumiseen. Tässä kokeellisessa työssä aerosolivirtausreaktorimenetelmää käytettiin valmistamaan nanohiukkasia lohko- ja oksastetuista kopolymeereistä. Tässä menetelmässä esiliuos, joka sisältää kopolymeerit ja mahdolliset muut molekyylit, pisaroidaan kantokaasuun aerosoliksi ja johdetaan virtausreaktoriin. Liuotin haihtuu aerosolipisaroista, jotka kuivuvat kiinteiksi nanohiukkasiksi. Tutkitut kopolymeerit olivat poly(styreeni-lohko-4-vinyylipyridiini) (PS-b-P4VP), lämpövasteellinen hydrogeeli poly(styreeni-lohko-N-isopropyyliakryyliamidi-lohko-styreeni) (PS-b-PNIPAm-b-PS) sekä oksastettu poly-L-lysiini(dodekyylibenzeenisulfoninen happo) (PLL(DBSA)). Lisäksi lääkkeenkuljetussoveltuvuutta tutkittiin PS-b-PNIPAm-b-PS:llä ja PLL(DBSA):lla. Itsejärjestyminen PS-b-P4VP nanohiukkasissa riippui aerosolireaktorin lämpötilasta sekä liuottimen ja kopolymeerien koostumuksesta. Kiinnittämällä sivuketjuja sylintereitä muodostavaan P4VP:iin tuotettiin sipulimaisia hiukkasia, joissa sivuketjut muodostivat yksittäisen kerroksen P4VP-lamellien väliin. Lisäämällä sivuketjujen määrää asteittain tämä rakenne muuttui smektisiksi lamelleja vastaan kohtisuoriksi tasoiksi. Suurin sivuketjujen määrä johti sipulirakenteen hajoamiseen. PS-b-PNIPAm-b-PS muodosti nanohiukkasissa sipulimaisia, gyroidimaisia sekä pallomaisia sisärakenteita, joissa PNIPAm oli matriisimateriaali ja PS muodosti fyysisesti ristisilloittavat alueet. Pallomaisen ja gyroidimaisen sisärakenteen omaavat nanohiukkaset turposivat vedessä 20 °C lämpötilassa. 1,8-ANS fluoresenssi-molekyylin vapautus oli nopeinta gyroidimaisista ja hitainta pallorakenteisista nanohiukkasista. Vapautukset olivat nopeampia 25 °C:ssa kuin 45 °C:ssa. PLL(DBSA):n itsejärjestyminen alpha-kierteisiin tai beta-laskoksiin oli hallittavissa liuottimella ja lämpötilalla. Beta-laskokset ilmenivät ~3 nm paksuina lamelleina nanohiukkasien pinnalla ja alpha-kierteet matomaisina alueina nanohiukkasien sisällä. Budesonidi ja ketoprofeeni estivät beta-laskosten muodostumisen nanohiukkasiin. Lääkkeenvapautus nanohiukkasista paransi huonoliukoisen budesoniden vapautusta.

Julkaisun otsikon käännös	Lohko- ja oksastettujen polymeerien itsejärjestyminen aerosolinanohiukkasissa
Alkuperäiskieli	Englanti
Pätevyys	Tohtorintutkinto
Myöntävä instituutio	Aalto-yliopisto
Valvoja/neuvonantaja	Kauppinen, Esko, Vastuuprofessori Raula, Janne-Juhani, Ohjaaja
Kustantaja	Aalto University
Painoksen ISBN	978-952-60-6311-9
Sähköinen ISBN	978-952-60-6312-6
Tila	Julkaistu - 2015
OKM-julkaisutyyppi	G5 Artikkeliväitöskirja

Tutkimusalat

aerosoli
lohkopolymeeri
itsejärjestyminen
nanohiukkanen
lääkkeenvapautus

Pääsy asiakirjaan

http://urn.fi/URN:ISBN:978-952-60-6312-6Lisenssi: Määrittelemätön

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@phdthesis{2adb7bc285944dcc9de226e75c5b1503,

title = "Self-assembly of Block and Graft Copolymers in Aerosol Nanoparticles",

abstract = "This study examined how to control the self-assembly of block and graft copolymers during the aerosol process, which produces nanoparticles with phase-separated inner structure and phase dimensions ranging from 3 nm to 30 nm. The nanoparticles were also studied for the possibility of their use as a drug carriers. Block copolymers consist of two or more chemically different polymer blocks covalently bound together. In graft copolymers molecules are bound as side-chains to the copolymer backbone. The chemical differences within the copolymer lead to phase-separation: the different parts of the copolymer segregate into separate nano-sized domains. The aerosol flow reactor method was used to prepare nanoparticles of block and graft copolymers. In this method, a precursor solution containing the copolymers and any additional molecules is atomized into an aerosol reactor. Laminar gas flow carries the aerosol into the reactor, in which the solvent evaporates and the aerosol droplets dry into solid nanoparticles. The studied copolymers were poly(styrene-block-4-vinylpyridine) (PS-b-P4VP), a temperature responsive hydrogel poly(styrene-block-N-isopropylacrylamide-block-styrene) (PS-b-PNIPAm-b-PS), and a graft copolymer poly-L-lysine(dodecylbenzenesulfonic acid) (PLL(DBSA)). Furthermore, studies were conducted on PS-b-PNIPAm-b-PS and PLL(DBSA) as potential drug carriers. The self-assembly within the PS-b-P4VP aerosol nanoparticles depended on the copolymer composition, annealing temperature, and solvent composition. Low CholHS side-chain content in the cylinder-forming P4VP resulted in onion-like particles with single CholHS layers, which were sandwiched between P4VP lamellae. Increasing the CholHS content led to smectic P4VP(CholHS) layers perpendicular to the polymer domain interfaces. The highest content resulted in a breakdown of the onion-like structure. PS-b-PNIPAm-b-PS formed nanoparticles with onion-like, gyroid-like, and spherical inner structures with a PNIPAm matrix and physically cross-linking polystyrene domains. Particles with spherical and gyroid-like morphologies swell considerably in water at 20 °C. The release of the incorporated 1,8-ANS fluorescence probe was fastest with the gyroidal and slowest with the sphere-forming morphology. The releases were faster at 25 °C than at 45 °C. Self-assembly of PLL(DBSA) into alpha-helical or beta-sheet secondary structure was controllable with solvent and temperature. The beta-sheet conformation manifested as ~3 nm thick lamellae on the particle surface while alpha-helix formed worm-like domains in the core. Added drugs budesonide and ketoprofen prevented beta-sheet formation and PLL(DBSA)−drug nanoparticles were in the alpha-helical conformation. Drug release from nanoparticles improved the solubility of the poorly soluble budesonide.",

keywords = "aerosol, block copolymer, self-assembly, nanoparticle, drug release, aerosoli, lohkopolymeeri, itsej{\"a}rjestyminen, nanohiukkanen, l{\"a}{\"a}kkeenvapautus, aerosol, block copolymer, self-assembly, nanoparticle, drug release",

author = "Antti Rahikkala",

year = "2015",

language = "English",

isbn = "978-952-60-6311-9",

series = "Aalto University publication series DOCTORAL DISSERTATIONS",

publisher = "Aalto University",

number = "106",

address = "Finland",

school = "Aalto University",

}

TY - BOOK

T1 - Self-assembly of Block and Graft Copolymers in Aerosol Nanoparticles

AU - Rahikkala, Antti

PY - 2015

Y1 - 2015

N2 - This study examined how to control the self-assembly of block and graft copolymers during the aerosol process, which produces nanoparticles with phase-separated inner structure and phase dimensions ranging from 3 nm to 30 nm. The nanoparticles were also studied for the possibility of their use as a drug carriers. Block copolymers consist of two or more chemically different polymer blocks covalently bound together. In graft copolymers molecules are bound as side-chains to the copolymer backbone. The chemical differences within the copolymer lead to phase-separation: the different parts of the copolymer segregate into separate nano-sized domains. The aerosol flow reactor method was used to prepare nanoparticles of block and graft copolymers. In this method, a precursor solution containing the copolymers and any additional molecules is atomized into an aerosol reactor. Laminar gas flow carries the aerosol into the reactor, in which the solvent evaporates and the aerosol droplets dry into solid nanoparticles. The studied copolymers were poly(styrene-block-4-vinylpyridine) (PS-b-P4VP), a temperature responsive hydrogel poly(styrene-block-N-isopropylacrylamide-block-styrene) (PS-b-PNIPAm-b-PS), and a graft copolymer poly-L-lysine(dodecylbenzenesulfonic acid) (PLL(DBSA)). Furthermore, studies were conducted on PS-b-PNIPAm-b-PS and PLL(DBSA) as potential drug carriers. The self-assembly within the PS-b-P4VP aerosol nanoparticles depended on the copolymer composition, annealing temperature, and solvent composition. Low CholHS side-chain content in the cylinder-forming P4VP resulted in onion-like particles with single CholHS layers, which were sandwiched between P4VP lamellae. Increasing the CholHS content led to smectic P4VP(CholHS) layers perpendicular to the polymer domain interfaces. The highest content resulted in a breakdown of the onion-like structure. PS-b-PNIPAm-b-PS formed nanoparticles with onion-like, gyroid-like, and spherical inner structures with a PNIPAm matrix and physically cross-linking polystyrene domains. Particles with spherical and gyroid-like morphologies swell considerably in water at 20 °C. The release of the incorporated 1,8-ANS fluorescence probe was fastest with the gyroidal and slowest with the sphere-forming morphology. The releases were faster at 25 °C than at 45 °C. Self-assembly of PLL(DBSA) into alpha-helical or beta-sheet secondary structure was controllable with solvent and temperature. The beta-sheet conformation manifested as ~3 nm thick lamellae on the particle surface while alpha-helix formed worm-like domains in the core. Added drugs budesonide and ketoprofen prevented beta-sheet formation and PLL(DBSA)−drug nanoparticles were in the alpha-helical conformation. Drug release from nanoparticles improved the solubility of the poorly soluble budesonide.

AB - This study examined how to control the self-assembly of block and graft copolymers during the aerosol process, which produces nanoparticles with phase-separated inner structure and phase dimensions ranging from 3 nm to 30 nm. The nanoparticles were also studied for the possibility of their use as a drug carriers. Block copolymers consist of two or more chemically different polymer blocks covalently bound together. In graft copolymers molecules are bound as side-chains to the copolymer backbone. The chemical differences within the copolymer lead to phase-separation: the different parts of the copolymer segregate into separate nano-sized domains. The aerosol flow reactor method was used to prepare nanoparticles of block and graft copolymers. In this method, a precursor solution containing the copolymers and any additional molecules is atomized into an aerosol reactor. Laminar gas flow carries the aerosol into the reactor, in which the solvent evaporates and the aerosol droplets dry into solid nanoparticles. The studied copolymers were poly(styrene-block-4-vinylpyridine) (PS-b-P4VP), a temperature responsive hydrogel poly(styrene-block-N-isopropylacrylamide-block-styrene) (PS-b-PNIPAm-b-PS), and a graft copolymer poly-L-lysine(dodecylbenzenesulfonic acid) (PLL(DBSA)). Furthermore, studies were conducted on PS-b-PNIPAm-b-PS and PLL(DBSA) as potential drug carriers. The self-assembly within the PS-b-P4VP aerosol nanoparticles depended on the copolymer composition, annealing temperature, and solvent composition. Low CholHS side-chain content in the cylinder-forming P4VP resulted in onion-like particles with single CholHS layers, which were sandwiched between P4VP lamellae. Increasing the CholHS content led to smectic P4VP(CholHS) layers perpendicular to the polymer domain interfaces. The highest content resulted in a breakdown of the onion-like structure. PS-b-PNIPAm-b-PS formed nanoparticles with onion-like, gyroid-like, and spherical inner structures with a PNIPAm matrix and physically cross-linking polystyrene domains. Particles with spherical and gyroid-like morphologies swell considerably in water at 20 °C. The release of the incorporated 1,8-ANS fluorescence probe was fastest with the gyroidal and slowest with the sphere-forming morphology. The releases were faster at 25 °C than at 45 °C. Self-assembly of PLL(DBSA) into alpha-helical or beta-sheet secondary structure was controllable with solvent and temperature. The beta-sheet conformation manifested as ~3 nm thick lamellae on the particle surface while alpha-helix formed worm-like domains in the core. Added drugs budesonide and ketoprofen prevented beta-sheet formation and PLL(DBSA)−drug nanoparticles were in the alpha-helical conformation. Drug release from nanoparticles improved the solubility of the poorly soluble budesonide.

KW - aerosol

KW - block copolymer

KW - self-assembly

KW - nanoparticle

KW - drug release

KW - aerosoli

KW - lohkopolymeeri

KW - itsejärjestyminen

KW - nanohiukkanen

KW - lääkkeenvapautus

KW - aerosol

KW - block copolymer

KW - self-assembly

KW - nanoparticle

KW - drug release

M3 - Doctoral Thesis

SN - 978-952-60-6311-9

T3 - Aalto University publication series DOCTORAL DISSERTATIONS

PB - Aalto University

ER -

Self-assembly of Block and Graft Copolymers in Aerosol Nanoparticles

Abstrakti

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