Small-Angle Neutron Scattering Studies on the Multilamellae Formed by Mixing Lamella-Forming Cationic Diblock Copolymers with Lipids and Their Interaction with DNA

详细信息    查看全文

• 作者：Po-Wei Yang ; Tsang-Lang Lin ; I-Ting Liu ; Yuan Hu ; U-Ser Jeng ; Elliot Paul Gilbert
• 刊名：Langmuir
• 出版年：2016
• 出版时间：February 23, 2016
• 年：2016
• 卷：32
• 期：7
• 页码：1828-1835
• 全文大小：511K
• ISSN：1520-5827

文摘

We demonstrate that the lamella-forming polystyrene-block-poly(N-methyl-4-vinylpyridinium iodine) (PS-b-P4VPQ), with similar sizes of the PS and P4VPQ blocks, can be dispersed in the aqueous solutions by forming lipid/PS-b-P4VPQ multilamellae. Using small-angle neutron scattering (SANS) and 1,2-dipalmitoyl-d₆₂-sn-glycero-3-phosphocholine (d₆₂-DPPC) in D₂O, a broad correlation peak is found in the scattering profile that signifies the formation of the loosely ordered d₆₂-DPPC/PS-b-P4VPQ multilamellae. The thicknesses of the hydrophobic and hydrophilic layers of the d₆₂-DPPC/PS-b-P4VPQ multilamellae are close to the PS layer and the condensed brush layer thicknesses as determined from previous neutron reflectometry studies on the PS-b-P4VPQ monolayer at the air–water interface. Such well-dispersed d₆₂-DPPC/PS-b-P4VPQ multilamellae are capable of forming multilamellae with DNA in aqueous solution. It is found that the encapsulation of DNA in the hydrophilic layer of the d₆₂-DPPC/PS-b-P4VPQ multilamellae slightly increases the thickness of the hydrophilic layer. Adding CaCl₂ can enhance the DNA adsorption in the hydrophilic brush layer, and it is similar to that observed in the neutron reflectometry study of the DNA adsorption by the PS-b-P4VPQ monolayer.