Mixed Silane‐based Self‐assembled Monolayers Deposited on Fluorine Doped Tin Oxide as Model System for Development of Biosensors for Toxin Detection

Abstract

In this work mixed hybrid phospholipid bilayers (mhBLM) were deposited on fluorine doped tin oxide (FTO) films. Two component silane‐based self‐assembled monolayers (SAMs) formed on FTO surface trigger vesicle fusion and formation of mhBLMs which are stable, can be easily regenerated, and therefore, used for multiple experiments. We found that certain chemical and physical conditions under which mixed SAMs are fabricated translate into functional properties of mhBLMs. In all cases we observed interaction of melittin with mhBLMs demonstrating biological relevance of these biomimetic surface constructs and their possible application in biosensors for toxin detection.

Formation of mixed hybrid bilayer lipid membrane on transparent thin film oxide electrodes

“…4, properties of mhBLM does not change over 18 h. Previously, a similar experiment was carried out using methyltrichlorosilane (MTS) as a backfiller [14]. The authors showed (see supporting information [14]) that the membrane is stable over hours and pore forming toxins can be incorporated into the membrane. Therefore, mhBLMs obtained in this study can be applied for the incorporation of pore forming toxins as well.…”

“…During the hydrolysis reaction between silane and oxide surface strong Si-O-Sn bonds are formed which contribute to robust SAM formation [13]. One important advantage of silanised oxide surfaces is suitability for multi-cycle hybrid bilayer lipid membrane formation and regeneration [4,6,14,15], particularly due to the strength of the Si-O-Sn bond. In contrary, for the gold/ alkylthiol system, the phospholipid bilayer could not be immobilised several times because a mixed monolayer rearranges to packed islands of long alkylchain molecules up to 72 h exposure to an aqueous solution [2].…”

“…In the current study, following the methodology which was employed for the assembly of tethered bilayers on thin gold film supports [3], we raised the research question if sufficient fluidity of bilayers immobilised on the metal oxide surface can be achieved by designing the mixed hybrid phospholipid bilayer membrane (mhBLM) [14]. In particular, by designing the mixed self-assembled silane monolayers consisting of short chain spacers and long alkyl chain anchor molecules we expected that such anchor layer would allow the formation of tethered bilayer providing a sufficient flexibility of the proximal to a surface phospholipid monolayer for the functional reconstitution of transmembrane proteins.…”

Tethered Bilayer Membrane Formation on Silanized Fluorine Doped Tin Oxide Surface

“…16 Transmembrane proteins (vaginolysin, 56, 8 kDa) could not penetrate such rigid structure therefore, in further studies, long alkylchain OTS was diluted with methyltrichlorosilane (MTS), in order to produce less hydrophobic and less rigid SAM. 24 Relatively small peptide melittin (2, 6 kDa) did penetrate the membrane however, the lack of space between the solid support and the lipid bilayer, impeded reconstitution of α-hemolysin (33 kDa) to the membrane.…”

Tin Oxide/Nitrogen‐Doped Graphene Quantum Dots Composite Nanotubes: An Efficient Electrode for Supercapacitors

“…In general most of the metal oxide semiconductors (MOS) such as RuO 2 [9,10], NiO [11], SnO 2 [12], MnO 2 [13,14], Fe 3 O 4 [15], CuO [16], ZnO [17], and CoO [18] are having a significant contribution for the SC applications [19]. Tin oxide (SnO 2 ) is well-known among MOS due to its vast applications such as in gas sensors [20,21], biosensors [22,23], solar cells [24,25], Li-ion battery materials [26,27], photocatalytic applications [28],…”