Investigation of pH and concentration influence on layer-by-layer self-assembly for nickel(II)phthalocyanine-tetrasulfonic acid tetrasodium salt coatings

2019 ◽  
Vol 23 (01n02) ◽  
pp. 84-90 ◽  
Author(s):  
Yonca Belce ◽  
Fevzi Ç. Cebeci
Keyword(s):  
Thin Film ◽  
Self Assembly ◽  
Electrostatic Interactions ◽  
Ph Value ◽  
Film Formation ◽  
Layer By Layer ◽  
Lbl Assembly ◽  
Layer Deposition ◽  
Vis Spectroscopy ◽  
Ionic Density

Porphyrins and phthalocyanines are widely studied molecules for various functional applications. Researchers have investigated these photoactive compounds for electrochemical, sensor, semiconductor and photodynamic therapy purposes. Layer-by-layer (LbL) self-assembly is preferred for its simple, environmentally-friendly and water-based features compared to other coating techniques in the literature. Coating thickness can be controlled on the order of nanometers by LbL mechanism. Multilayer thin film formation of diverse phthalocyanine-based molecules is examined in terms of molecular orientation and temperature dependency by the LbL method. However, as well as concentration and temperature, the pH of the coating medium is another challenging parameter in the LbL approach. Film thickness and layer distribution are influenced by pH value, changing ionic density and hence the strength of electrostatic interactions during LbL assembly. In this study, layer-by-layer deposition of branched poly(ethyleneimine)/nickel(II)phthalocyanine-tetrasulfonic acid tetrasodium salt (NiPcTS) coating pair is studied. Impact of pH and concentration of NiPcTS on thin film properties are tested for four different pH conditions. Corresponding analysis is made by UV-vis spectroscopy, surface profiler and quartz-crystal microbalance. LbL deposition of NiPcTS is homogeneously controlled and 98 nm thick films are obtained in the presence of acidic media.

Development of a Novel Micro-Spray-Assembly Process for Multilayer Ultra-Thin Film Formation

2005 ◽  
Vol 23 ◽  
pp. 331-334
Author(s):  
Zheng Peng ◽  
Ling Xue Kong
Keyword(s):  
Thin Film ◽  
Self Assembly ◽  
Ph Value ◽  
Film Formation ◽  
Automatic Device ◽  
Assembly Process ◽  
Molecular Concentration ◽  
N2 Flow Rate ◽  
Manufacturing Parameters ◽  
Ultra Thin Film

A novel micro-spray-assembly process and an automatic device to fabricate multilayer ultra-thin film are introduced. Employing self-assembly monolayer (SAM) technique, ultra-thin film can be assembled by utilizing the micro-spray-assembly device. The thickness and roughness of each monolayer can be controlled by varying various materials attributes, i.e., deposition time, ionic strength, pH value, molecular concentration and by selecting different manufacturing parameters of the automatic device such as spraying rate, size of micro-drop, N2 flow rate, temperature of N2 flow.

Radical-triggered cross-linking for molecular layer deposition of SiAlCOH hybrid thin films

2021 ◽  
Author(s):  
Kristina Ashurbekova ◽  
Karina Ashurbekova ◽  
Iva Saric ◽  
Evgeny Modin ◽  
Mladen Petravic ◽  
...  
Keyword(s):  
Thin Film ◽  
Film Growth ◽  
Molecular Layer ◽  
Thin Film Growth ◽  
Cross Linking ◽  
Layer By Layer ◽  
Molecular Layer Deposition ◽  
Layer Deposition ◽  
Hybrid Thin Films ◽  
Enhanced Stability

We developed a thin film growth with a radical-initiated cross-linking of vinyl groups in a layer-by-layer manner via molecular layer deposition (MLD). The cross-linked film exhibited improved properties like 12% higher density and enhanced stability compared to the non-cross-linked film.

scholarly journals Carbon Nano-Onions Reinforced Multilayered Thin Film System for Stimuli-Responsive Drug Release

Pharmaceutics ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 1208
Author(s):  
Narsimha Mamidi ◽  
Ramiro Velasco Delgadillo ◽  
Aldo Gonzáles Ortiz ◽  
Enrique Barrera
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Drug Release ◽  
Self Assembly ◽  
Critical Role ◽  
Layer By Layer ◽  
Film System ◽  
Stimuli Responsive ◽  
Ph Responsive ◽  
Thin Film System

Herein, poly (N-(4-aminophenyl) methacrylamide))-carbon nano-onions (PAPMA-CNOs = f-CNOs) and anilinated-poly (ether ether ketone) (AN-PEEK) have synthesized, and AN-PEEK/f-CNOs composite thin films were primed via layer-by-layer (LbL) self-assembly for stimuli-responsive drug release. The obtained thin films exhibited pH-responsive drug release in a controlled manner; pH 4.5 = 99.2% and pH 6.5 = 59.3% of doxorubicin (DOX) release was observed over 15 days. Supramolecular π-π stacking interactions between f-CNOs and DOX played a critical role in controlling drug release from thin films. Cell viability was studied with human osteoblast cells and augmented viability was perceived. Moreover, the thin films presented 891.4 ± 8.2 MPa of the tensile strength (σult), 43.2 ± 1.1 GPa of Young’s modulus (E), and 164.5 ± 1.7 Jg−1 of toughness (K). Quantitative scrutiny revealed that the well-ordered aligned nanofibers provide critical interphase, and this could be responsible for augmented tensile properties. Nonetheless, a pH-responsive and mechanically robust biocompatible thin-film system may show potential applications in the biomedical field.

Tunable Silver Leaching from Polyelectrolyte Multilayers Thin Films

2013 ◽  
Vol 701 ◽  
pp. 145-149 ◽  
Author(s):  
Sirorat Wacharanad ◽  
Stephan Thierry Dubas
Keyword(s):  
Silver Nanoparticles ◽  
Suture Material ◽  
Chemical Reduction ◽  
Layer By Layer ◽  
Capping Agent ◽  
Bacterial Reduction ◽  
Bacterial Colony ◽  
Surgical Suture ◽  
Layer Deposition ◽  
Vis Spectroscopy

Silver nanoparticles were deposited on glass slides and surgical suture as antibacterial agent. The silver nanoparticles were prepared by chemical reduction with sodium borohydride and using a synthetic polyelectrolyte as capping agent. Poly (4-styrenesulfonic acid-co-maleic acid) sodium salt PSSMA was used to stabilize the silver nanoparticles and provide an anionic surface charge which then allowed the layer-by-layer deposition method with poly (dially dimethyl ammonium chloride) PDADMAC. Various concentration of capping agent were used to prepare the silver nanoparticles which were then deposited on glass slide and surgical suture. The layer-by-layer deposition of the nanoparticles was studied using UV-Vis spectroscopy by monitoring the intensity of the characteristic Plasmon band of the nanoparticles at 400nm. The leaching of the silver nanoparticles in buffered solutions of pH 3,7 and 9 was monitored by recording the decrease in absorbance of silver nanoparticles film as a function of time for each pH solutions and each capping concentrations. Finally, suture material coated with silver nanoparticles were tested for their antibacterial activity against Staphylococcus aureus and results showed that all coated sutures had more than 99% bacterial reduction. So these suture material could be applied to use in medical products for promoted wound healing and decreased bacterial colony leading to relieve inflammation of patient.

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