Halochromic Textile Materials as Innovative pH-Sensors

Recently, an increasing interest in pH-sensitive textiles is recognized. These chromic textiles can be used as flexible sensors for various applications. The aim of the current research is to develop textile pH-sensors through the application of pH-sensitive dyes on various textile materials using different techniques. The results of our study show that halochromic dyes can be incorporated into conventional textiles by a conventional dyeing technique. Also coating the fabrics with a sol-gel layer containing the halochromic dye proved to be successful. The majority of these developed materials showed a clearly visible color change with a pH-variation. The response of the sensors was dependent on the density of the fabric but was generally relatively fast, especially for the sol-gel treated fabrics. The halochromic coloration of nanofibres was realized by directly adding the dyes during the fiber formation, which was shown to be highly effective. Again, a clear halochromic shift was observed. The response of these sensors was fast thanks to the high porosity of nanofibrous non-wovens. Yet, it should be kept in mind that the halochromic behavior of the dyes in the textile matrix altered compared to their behavior in solution which is most likely attributed to dye-fiber interactions. Generally we can conclude that various coloration techniques showed to be effective for the development of innovative textile pH-sensors.

Download Full-text

Coloration and application of pH-sensitive dyes on textile materials

Coloration Technology ◽

10.1111/j.1478-4408.2011.00361.x ◽

2012 ◽

Vol 128 (2) ◽

pp. 82-90 ◽

Cited By ~ 48

Author(s):

Lien Van der Schueren ◽

Karen De Clerck

Keyword(s):

Ph Sensitive ◽

Textile Materials ◽

Ph Sensitive Dyes

Download Full-text

Entrapment of phenol red pH indicator into polyaniline sol-gel

International Journal of Electrical & Electronic Systems Research (IEESR) ◽

10.24191/ieesr.v9i1.1368 ◽

2019 ◽

Vol 9 (1) ◽

pp. 57

Author(s):

Norliza Othman ◽

Uzer Mohd Noor ◽

Sukreen Hana Herman

Keyword(s):

Optical Sensors ◽

High Performance ◽

Low Cost ◽

Sol Gel ◽

Phenol Red ◽

Ph Sensors ◽

Ph Indicator ◽

Simple Method ◽

Promising Alternative ◽

Ph Variation

Optical pH sensors offer a promising alternative method over the existence pH electrochemical sensor and other. Due to ability to achieve high performance, electrical passive operation, simplicity and price effectiveness. Recently, significant research efforts have been devoted to pH sensors for the detection of pH variation in high resolution short range changes. It becomes important to consider ways to heighten the sensitivity of the indicator by improving combination of the material and simple method of sensor fabrication. Effort has been put in studying the fabrication and the sensitivity of film towards pH range in physiological application. Most optical sensors consist of an indicator which is immobilized in a polymer matrix. In this research, polyaniline act as a sol - gel matrix to support pH sensitive indicator molecules which is phenol red. Polyaniline has been found to be versatile functional material which is the most suitable organic material to act as a matrix in aqueous medium and capability to sense on pH changes. The combination between polyaniline with phenol red will enhance the sensitivity of the sensor. The sensing capabilities of the device in term its optical absorption intensity with different pH values were explored. Besides that, simpler and low cost methods was prepared and developed. Through the final investigations, it was found that the phenol red immobilized in a polyaniline film on a portion of fiber optic developed by deposited for 4 layers at thickness is 88.46 nm, withdrawal speed with 15 mm/s and re-cladded length is 15mm/s is the best optimized parameters.

Download Full-text

A Molecularly Imprinted Sol-Gel Electrochemical Sensor for Naloxone Determination

Nanomaterials ◽

10.3390/nano11030631 ◽

2021 ◽

Vol 11 (3) ◽

pp. 631

Author(s):

Narges Shaabani ◽

Nora W. C. Chan ◽

Abebaw B. Jemere

Keyword(s):

Indium Tin Oxide ◽

Sol Gel ◽

Electrochemical Techniques ◽

Electrochemical Determination ◽

Multiwall Carbon Nanotube ◽

Molecularly Imprinted ◽

Gel Layer ◽

Sensing Material ◽

Relative Standard ◽

Optimized Conditions

A molecularly imprinted sol-gel is reported for selective and sensitive electrochemical determination of the drug naloxone (NLX). The sensor was developed by combining molecular imprinting and sol-gel techniques and electrochemically grafting the sol solution onto a functionalized multiwall carbon nanotube modified indium-tin oxide (ITO) electrode. The sol-gel layer was obtained from acid catalyzed hydrolysis and condensation of a solution composed of triethoxyphenylsilane (TEPS) and tetraethoxysilane (TES). The fabrication, structure and properties of the sensing material were characterized via scanning electron microscopy, spectroscopy and electrochemical techniques. Parameters affecting the sensor’s performance were evaluated and optimized. A sensor fabricated under the optimized conditions responded linearly between 0.0 µM and 12 µM NLX, with a detection limit of 0.02 µM. The sensor also showed good run-to-run repeatability and batch-to-batch performance reproducibility with relative standard deviations (RSD) of 2.5–7.8% (n = 3) and 9.2% (n = 4), respectively. The developed sensor displayed excellent selectivity towards NLX compared to structurally similar compounds (codeine, fentanyl, naltrexone and noroxymorphone), and was successfully used to measure NLX in synthetic urine samples yielding recoveries greater than 88%.

Download Full-text

THE EFFECT OF COMPOSITION CHANGE IN SOL-GEL SYNTHESIZED PSC

Biomedical Engineering Applications Basis and Communications ◽

10.4015/s101623720800060x ◽

2008 ◽

Vol 20 (01) ◽

pp. 53-59

Author(s):

Wen-Hsi Wang ◽

Yuan-Ling Lee ◽

Chun-Pin Lin ◽

Feng-Huei Lin

Keyword(s):

Setting Time ◽

Sol Gel ◽

Hydration Product ◽

Xrd Pattern ◽

Ph Variation ◽

Initial Strength ◽

Filling Materials ◽

Retrograde Filling ◽

Significant Difference ◽

Sol Gel Process

Modified calcium silicate cement had previously been developed as a dental retrograde filling. It had great sealing ability, good biocompatibility, and anti-bacterial properties. However, its clinical application was limited by a long setting time and poor handling property. In previous study,1, 2 the setting property of PSC was greatly improved due the sol-gel process, without the addition of transition metal element. In this study, different ratio of starting material of PSC was prepared. The composition of each group was also altered with the ratio of the starting materials according to the result of XRD pattern. There is no significant difference in pH variation profile between each group. Even though low C 3 S / C 4 AF ratio (DX631 and DX541 groups) possessed high initial strength at first 24 hours after hydration, there was no increase in strength ever since according to the result of microhardness. However, the groups with high C 3 S / C 4 AF ratio (DX811 and DX721 groups) possessed relatively low initial strength at 24 hours after hydration, but the strength increased rapidly and continuously at least for the next six days of hydration. Moreover, the peak intensity of hydration product (Portlandite) on XRD pattern in DX811 group was much higher than other three groups, and this was also in agreement with the result of microhardness. DX811 group is determined to be the optimal one for the further development in the application as root-end filling materials.

Download Full-text

Effect of coating composition on the anticorrosion performance of a silane sol–gel layer on mild steel

RSC Advances ◽

10.1039/c5ra21744j ◽

2015 ◽

Vol 5 (129) ◽

pp. 106485-106491 ◽

Cited By ~ 3

Author(s):

A. Foroozan E. ◽

R. Naderi

Keyword(s):

Mild Steel ◽

Electrochemical Impedance ◽

Steel Substrate ◽

Sol Gel ◽

Gel Layer ◽

Gel Film ◽

Coating Composition ◽

Anticorrosion Performance ◽

Protective Performance ◽

Mild Steel Substrate

In this study, the effect of coating composition on the protective performance of an eco-friendly silane sol–gel film applied on a mild steel substrate was investigated using electrochemical impedance spectroscopy and surface analysis methods.

Download Full-text

Consequence of pH variation on the dielectric properties of Cr-doped lithium ferrite nanoparticles synthesized by the sol–gel method

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2015.05.017 ◽

2015 ◽

Vol 645 ◽

pp. 171-177 ◽

Cited By ~ 10

Author(s):

Manish Srivastava ◽

R.K. Mishra ◽

Jay Singh ◽

Neha Srivastava ◽

Nam Hoon Kim ◽

...

Keyword(s):

Dielectric Properties ◽

Sol Gel ◽

Ferrite Nanoparticles ◽

Lithium Ferrite ◽

Ph Variation ◽

Gel Method ◽

Sol Gel Method

Download Full-text

Textile materials with a pH‐sensitive function

International Journal of Clothing Science and Technology ◽

10.1108/09556221111136539 ◽

2011 ◽

Vol 23 (4) ◽

pp. 269-274 ◽

Cited By ~ 12

Author(s):

Lien Van der Schueren ◽

Karen De Clerck

Keyword(s):

Ph Sensitive ◽

Textile Materials ◽

Sensitive Function

Download Full-text

Properties of Pinus modified with silicon–titanium binary oxides

BioResources ◽

10.15376/biores.16.1.747-763 ◽

2020 ◽

Vol 16 (1) ◽

pp. 747-763

Author(s):

Xiaoling Liu ◽

Songwu Chen ◽

Yunlin Fu

Keyword(s):

Wood Surface ◽

Color Change ◽

Sol Gel ◽

Resistance Testing ◽

Chemical Bonds ◽

Noticeable Increase ◽

Aging Resistance ◽

Tio2 Gel ◽

Unmodified Wood ◽

Modified Wood

Modification of Pinus yunnanensis using SiO2–TiO2 was carried out via the sol–gel method. The aim was to improve the hydrophobicity, aging resistance, and photocatalysis of the wood surface via the formation of new chemical bonds with penetrated SiO2 and TiO2. The air-dried P. yunnanensis wood underwent penetration, gelation, aging, and drying. The wood was exposed to high temperatures for modification, and its microstructure, composition, photodegradability, resistance to aging, dimensional stability, and hydrophobicity were then determined. The results indicated that during modification, SiO2–TiO2 gel was generated in the wood, and the content of the gel increased as penetration time was extended. No structural change in the wood was observed. Meanwhile, chemical bonds were formed among SiO2, TiO2, and wood. The contact angle of the modified wood increased noticeably relative to that of unmodified wood. This increase indicated a noticeable increase in the hydrophobicity of the wood surface. The modified wood exhibited high photocatalytic degradation; however, its durability was not evident. The water absorption and thickness swelling of the modified wood markedly increased. After ultraviolet-aging resistance testing, the color change in the surface of the modified wood was noticeably less than that of the unmodified wood.

Download Full-text