Preferred deposition of phospholipids onto ferroelectric P(VDF-TrFE) films via polarization patterning

Abstract

Ferroelectric polarization can be used to assemble various organic and inorganic species and to create nanostructures with controlled properties. In this work, we used P(VDFTrFE) ultrathin films deposited by Langmuir-Blodgett technique as templates for the assembly of various phospholipids that are the essential components of cell membranes. It was observed that 1,2-Di-O-hexadecyl-sn-glycero-3-phosphocoline phospholipids (DHPC) form self-assembled structures (molecular domains) on bare P(VDF-TrFE) surfaces. These were revealed by the formation of homogenous and stable rounded blobs with diameters in the range 0.5-3 µm. Further, ferroelectric polymer films were polarized by the application of various voltages via conducting tip using Piezoresponse Force Microscopy (PFM) setup and PFM images were obtained showing controlled polarization distribution. After this, phospholipid molecules were deposited from the solution. Conventional Atomic Force Microscopy (AFM) experiments were then performed to assess the selectivity of the deposition process. It was observed that the deposition process is very sensitive to the concentration of the solution. The selective deposition was observed mainly at the polarization boundaries where the selectivity reached a maximum value of about 20-40%. In this way, the controlled assembly of organic molecules on the polymer surfaces could be achieved. In addition, the PFM tips could be functionalized by the phospholipids and switchable lines of the DHPC molecules on the P(VDF-TrFE) surface were then visualized by PFM.

Piezoelectricity and ferroelectricity in biomaterials: Molecular modeling and piezoresponse force microscopy measurements

“…It is also important that ferroelectric polarization can be used to assemble various organic and inorganic species and to create nanostructures with controlled properties (so-called polarization lithography). Following this approach, Heredia et al 42 used poly(vinylidene fluoride-co-trifluoroethylene) P(VDF-TrFE), ultrathin films deposited by the Langmuir Blodgett (LB) technique. The nanoscale properties of P(VDF-TrFE) LB layers were reported earlier.…”

“…The attraction of the dipoles existing in the lipid solution due to the polarization of the P(VDF-TrFE) surface seems to be based on dielectrophoresis (DEP). In this case, 42 these dipole moments do already exist, thus increasing the potential of DEP for scaling down and using it for the manipulation of nanosized objects such as DNA, proteins, nanotubes, nanoparticles and, potentially, with small individual molecules in a solution. When placed in electric field E, equal but opposite forces arise on each side of the dipole creating a torque s ¼ p  E. In a homogeneous electric field (gradE ¼ 0), the dipole molecules do not move, because the total force acting on the molecule is zero (Fg $ p grad E).…”

“…This review is thus devoted to recent findings of the piezoelectric and ferroelectric features in artificial structures based on crystalline amino acids (glycine), 40 peptides (self-assembled nanotubes), 41 and lipid/ferroelectric bilayers. 42 We hope that the understanding of the electromechanical behavior in these structures under an applied electric field will open a pathway for further insight to piezoelectric and ferroelectric phenomena in complex biological materials.…”

Computational Studies of PVDF and P(VDF-TrFE) Nanofilms Polarization During Phase Transition Revealed by Emission Spectroscopy

“…Области широкого применения ПВДФ и П(ВДФ-ТрФЭ) -в нанотехнологиях и микроэлектронике, устройствах хранения информации и новых энергонезависимых запоминающих устройствах [12]. И особенно в биомедицине и наномедицине -как многообещающие компоненты различных нанокомпозитов, сенсоров и имплантов, благодаря своим особым акустическим и пьезоэлектрическим свойствам, высокой совместимости со многими органическими и биологическими молекулами и тканями [13][14][15][16][17][18]. Тем не менее, многие из этих важных физических и структурных свойств и особенностей ПВДФ-полимерных тонких плёнок до сих пор неясны и недостаточно изучены.…”

“…Эта работа продолжает серию исследований сегнетоэлектрических свойств ультратонких ПВДФ-сополимерных плёнок ЛБ на наноуровне [11,[16][17][18]. Предложенный метод определения поляризации по изменению работы выходы, измеренной по методу ТСЭЭ спектроскопии, может быть широко использован как в нанотехнологиях, так и в нанобиомедицине, в особенности при разработке костных биоимплантатов, которые включают встроенные сенсоры (смарт-нанобиотехнологии).…”