Understanding the gas adsorption kinetics of Langmuir-Schaefer porphyrin films using two comparative sensing systems

Evyapan, Murat; Hassan, Aseel; Dunbar, Alan D. F.

doi:10.1016/j.snb.2017.07.103

Cited by 8 publications

(9 citation statements)

References 30 publications

(43 reference statements)

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“…The gas concentrations were calculated by the following Equation (1) [ 26 ]:

where c and V is the concentration (ppm) and volume (L) of the gas sample, respectively, ρ is density (g/mL) and Vs is the volume (μL) of the liquid sample, T is the temperature (Kelvin) and M is the molecular weight of analyte (g/mol). Gas stored bottles were sealed to prevent leaking, then stored at room temperature to be evaporated, and injected into the gas chamber with a syringe during detection.…”

Section: Methodsmentioning

confidence: 99%

Sensing Behavior of Metal-Free Porphyrin and Zinc Phthalocyanine Thin Film towards Xylene-Styrene and HCl Vapors in Planar Optical Waveguide

et al. 2021

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The sensing behavior of a thin film composed of metal-free 5, 10, 15, 20-tetrakis (p-hydroxy phenyl) porphyrin and zinc phthalocyanine complex towards m-xylene, styrene, and HCl vapors in a homemade planar optical waveguide (POWG), was studied at room temperature. The thin film was deposited on the surface of potassium ion-exchanged glass substrate, using vacuum spin-coating method, and a semiconductor laser light (532 nm) as the guiding light. Opto-chemical changes of the film exposing with hydrochloric gas, m-xylene, and styrene vapor, were analyzed firstly with UV-Vis spectroscopy. The fabricated POWG shows good correlation between gas exposure response and absorbance change within the gas concentration range 10–1500 ppm. The limit of detection calculated from the logarithmic calibration curve was proved to be 11.47, 21.08, and 14.07 ppm, for HCl gas, m-xylene, and styrene vapors, respectively. It is interesting to find that the film can be recovered to the initial state with trimethylamine vapors after m-xylene, styrene exposures as well as HCl exposure. The gas-film interaction mechanism was discussed considering protonation and π-π stacking with planar aromatic analyte molecules.

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“…The gas concentrations were calculated by the following Equation (1) [ 26 ]:

Section: Methodsmentioning

confidence: 99%

Sensing Behavior of Metal-Free Porphyrin and Zinc Phthalocyanine Thin Film towards Xylene-Styrene and HCl Vapors in Planar Optical Waveguide

et al. 2021

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“…But the absorption bands of thin film are in a wider band range where the individual molecules are present. Removal of the solvent, aggregation of molecules in thin film structure and/or increasing intermolecular interactions may cause some shift and broadening of absorption band [12,28,36].…”

Section: Characterization Of Spin Coated Filmsmentioning

confidence: 99%

“…The other reason could be the size of the toluene molecule which has a chain structure. Gas sensor studies revealed two different mechanisms while examining interaction between vapor molecules and sensor material [12,28]. One is surface interaction, where the vapor molecules directly interact with the surface of sensor material.…”

Section: Vapor Sensing Propertiesmentioning

confidence: 99%

“…The data of concentration dependence of a gas sensor states two crucial parameters which are the sensitivity (S) and the limit of detection (LOD). For a gas sensor, sensitivity is defined as the change of response per ppm (ppm −1 ) [12] and the LOD is defined as the lowest quantity (ppm) of the analyte can be detected by the sensor [11]. LOD can be described by the following equation ( 4) and parameters are summarized in table 3,…”

Section: Vapor Sensing Propertiesmentioning

confidence: 99%

“…Because the ideal sensor features like sensitivity and selectivity are directly related to the interaction between vapor molecule and sensing material [10,11]. With this purpose in mind, the interaction mechanism is the key feature and much of the reported research is to develop high sensitivity sensing material with clarifying the interaction mechanism [12,13].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Thin film preparation of polyphenol oxidase enzyme (PPO) and investigation of its organic vapor interaction mechanism

Evyapan,

Deniz

2023

J. Phys.: Condens. Matter

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This study investigated spin coated thin films of polyphenol oxidase enzyme (PPO) as vapor sensor to detect chloroform, acetone, ethyl acetate, isopropyl alcohol and toluene. Thin film of enzyme was produced onto a bio-composite (gelatine chitosan) first layer via 5000 rpm spin speed. UV-visible spectroscopy and Quartz Crystal Microbalance (QCM) measurements were carried out to analyze the reproducibility of PPO spun film. It was found that the PPO enzyme can be transferred onto a solid substrate as a solid state thin film form. The sensor films of PPO enzyme were exposed to various VOCs (chloroform, acetone, ethyl acetate, isopropyl alcohol and toluene) with different fixed concentrations. The sensing responses of PPO thin films versus five vapors were investigated using QCM as the time dependence frequency recording method. The PPO sensor films exhibited high sensitivity and fast responses against all VOCs. But the response rate and magnitude were changed depending on the chemical structure and the molecular size of the analyte vapor. Recorded frequency changes as monitored by QCM technique have been integrated with the Fick’s second law of diffusion to determine the diffusion coefficients of analyte vapors. The results showed that the interaction characteristics between PPO and the analytes can be considered in terms of two main processes which are surface interaction and diffusion. And it was concluded that the formation of these two processes during the interaction depend on the molecular size and functional group of the analytes. These results showed that enzymes can be integrated into vapor sensor system as active layer and are promising for further sensor studies. 

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Porphyrins as Colorimetric and Photometric Biosensors in Modern Bioanalytical Systems

2020

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Advances in porphyrin chemistry have provided novel materials and exciting technologies for bioanalysis such as colorimetric sensor array (CSA), photo‐electrochemical (PEC) biosensing, and nanocomposites as peroxidase mimetics for glucose detection. This review highlights selected recent advances in the construction of supramolecular assemblies based on the porphyrin macrocycle that provide recognition of various biologically important entities through the unique porphyrin properties associated with colorimetry, spectrophotometry, and photo‐electrochemistry.

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Understanding the gas adsorption kinetics of Langmuir-Schaefer porphyrin films using two comparative sensing systems

Cited by 8 publications

References 30 publications

Sensing Behavior of Metal-Free Porphyrin and Zinc Phthalocyanine Thin Film towards Xylene-Styrene and HCl Vapors in Planar Optical Waveguide

Sensing Behavior of Metal-Free Porphyrin and Zinc Phthalocyanine Thin Film towards Xylene-Styrene and HCl Vapors in Planar Optical Waveguide

Thin film preparation of polyphenol oxidase enzyme (PPO) and investigation of its organic vapor interaction mechanism

Porphyrins as Colorimetric and Photometric Biosensors in Modern Bioanalytical Systems

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