Layer‐by‐Layer Assembly of Light‐Responsive Polymeric Multilayer Systems

Abstract

wileyonlinelibrary.comcompositions, structures, and functions for several relevant applications. This goal has been achieved by engineering several nanostructured building blocks on surfaces through many processing methods. 'Bottom-up' methods, including Langmuir-Blodgett (LB), [1][2][3] self-assembled monolayers (SAMs), [4][5][6][7][8][9][10][11][12][13] and Layerby-Layer (LbL) assembly, [14][15][16][17][18][19] have been widely used to modify and effectively tailor the surface properties and simultaneously for assembling desired molecules with a high degree of control over organization and orientation. Therefore, these surface engineering strategies have been used to design and fabricate organized monolayer fi lms (in the case of SAM methodology) and multilayer assemblies (in the case of LB and LbL assembly approaches) with precisely layered structures, compositions, properties, and functions, and thus with enhanced performance at the molecular level. Furthermore, the bulk properties of nanostructured materials and the ability to precisely tailor the surface properties and fi nely tune the physicochemical properties and structures of engineered functional molecular assemblies have been recognized as having paramount importance for the scientifi c and engineering communities due to the broad range of possible applications in the biomedical, electronics, optics, catalysis, and energy research fi elds. [20][21][22] It is well known and commonly agreed that nature provides a great source of endless inspirations for designing highly sophisticated functional materials. Hence, scientists and engineers from different areas of chemistry, physics, engineering, biology, medicine, or biotechnology have been challenged to design and engineer environmentally sensitive biomimetic surfaces that would respond to specifi c external stimuli (e.g. temperature, pH, ionic strength, light, mechanical stress, electric, magnetic and ultrasonic fi elds, electric potential, specifi c biological moieties) in a very controllable and predictable manner, hence adjusting to our demands. Such smart surfaces have been developed by modifying surfaces with stimuliresponsive polymeric materials that ideally exhibit reversible switchable physicochemical properties (i.e., a polymer should be switched repeatedly rather than being designed for a single event), precisely tailored structures, compositions, and functions in response to changes in the surrounding environment. Layer-by-Layer (LbL) assembly is a simple and highly versatile method to modify surfaces and fabricate robust and highly-ordered nanostructured coatings over almost any type of substrate. Such versatility enables the incorporation of a plethora of building blocks, including materials exhibiting switchable properties, in a single device through a multitude of complementary intermolecular interactions. Switchable materials may undergo reversible physicochemical changes in response toa variety of external triggers. Although most of the works in the literature have been focusing on stimu...

Optical Properties of Hybrid Organic‐Inorganic Materials and their Applications

“…[301] Such method can be extended to wide range of optical materials and more generally light activated systems combining for instance nanoparticles, dyes, polyoxometallates with polyelectrolytes. [303] Another way of controlling the orientation is to intercalate the chromophore in the interlayer space of layered inorganic materials. This strategy was used in the early 90's by P.G.…”

Controlling Effective Aspect Ratio and Packing of Clay with pH for Improved Gas Barrier in Nanobrick Wall Thin Films

“…[1][2] Thin films have been created that passively block gas 3 and heat, 4 respond to light, 5 heat, 6 and pH 7 (in various ways), conduct electricity, 8 and release medicinal molecules. 9 LbL assembly involves depositing species with complementary functionality, with electrostatic interaction being the most extensively studied driving force.…”

Nanosized Building Blocks for Customizing Novel Antibiofilm Approaches

“…In addition, with the establishment of surface chemistry, NE surface attachment and assembling can be directed by specific chemical bonds (e.g., hydrogen) and interactions (e.g., covalent, electrostatic, hydrophobic, pi stacking), some even biologically driven (Fig. 1B, Table;Borges et al 2014;Taglietti et al 2014). Successful strategies for surface attachment and immobilization of molecules and macromolecules, especially proteins (Lee et al 2014;Zhu and Jun Loh 2015), are now being applied for on-site surface assembling of NEs and for generating surface coatings.…”

“…Antibacterial surfaces with silver (Marsich et al 2013;Borges et al 2014;Jia et al 2016) and polymeric (Horev et al 2015) nanostructures are recent examples of such functional surface design. In particular, a precise manipulation of chitosan layering was recently performed to generate controlled surface patterns containing AgNPs (Shuai et al 2013).…”

“…The resulting nanoengineered surface showed multifunctional properties, such as antifouling, combined with antibacterial properties, thus reducing the adhesion and viability of gram-positive (Staphylococcus aureus) and gram-negative (Pseudomonas aeruginosa) bacteria, without apparent cytotoxicity (i.e., against African green monkey kidney fibroblast-like cells; COS-7). NE attachment is usually induced by noncovalent bonds, especially with electrostatic (i.e., +/-charge combination) and other interactions (e.g., hydrogen bonds, hydrophobic, hostguest chemistry; Marsich et al 2013;Alghamdi et al 2014;Borges et al 2014;Horev et al 2015;Jia et al 2016). In some cases, an NE-surface attachment through covalent bonds can provide more resilient assemblies for preventing deterioration and undesired detachment of NEs (Mokkaphan et al 2014).…”