In this work, the possibility of application of free base porphyrin as a lipophilic pH chromoionophore for the preparation of optical cation-selective sensors was investigated. The properties of polymeric membranes, containing porphyrins of different structures, namely tetraphenylporphyrin (TPP) and octaethylporphyrin (OEP), were compared. Changes in equilibrium between protonated and deprotonated form of porphyrin, resulting from variations in ACh concentration, were evaluated. The influence of various factors (kind and quantity of anionic additive and porphyrin in the membrane phase, pH of sample solution) on initial equilibrium was studied. The best membrane composition was chosen as: TPP 3 wt.%, KTFPB 175 mol.% relative to ionophore, PVC:o-NPOE (1 : 4) and measuring buffer solution: 0.05 M MES, pH 4.5. Selectivity, response stability, reversibility and repeatability tests were carried out for chosen sensor. Developed sensor allowed for the determination of a model analyte, acetylcholine, at the concentration range of 10(-5) to 10(-2) M, both in stationary and flow-injection system. Sensor response was reversible and repeatable in the mentioned concentration range.
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http://dx.doi.org/10.1039/c0an00965b | DOI Listing |
J Mater Chem B
January 2025
Ningbo Key Laboratory of Biomedical Imaging Probe Materials and Technology, Laboratory of Advanced Theranostic Materials and Technology, Chinese Academy of Sciences (CAS) Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
The critical need for rapid cancer diagnosis and related illnesses is growing alongside the current healthcare challenges, unfavorable prognosis, and constraints in diagnostic timing. As a result, emphasis on surface-enhanced Raman spectroscopy (SERS) diagnostic methods, including both label-free and labelled approaches, holds significant promise in fields such as analytical chemistry, biomedical science, and physics, due to the user-friendly nature of SERS. Over time, the SERS detection sensitivity and specificity with nanostructured materials for SERS applications (NMs-SERS) in different media have been remarkable.
View Article and Find Full Text PDFClin Otolaryngol
January 2025
School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan.
Introduction: The nasoseptal flap (NSF) has become a widely favoured choice for reconstructing skull base defects following the endoscopic endonasal approach (EEA). However, the exposed septal cartilage and bone at the donor site often require an extended duration for secondary healing. This study investigated whether the free middle turbinate (MT) mucosa grafting at the septal donor site could mitigate post-operative nasal morbidity.
View Article and Find Full Text PDFCarbon-carbon (C/C) composites are attractive materials for high-speed flights and terrestrial atmospheric reentry applications due to their insulating thermal properties, thermal resistance, and high strength-to-weight ratio. It is important to understand the evolving structure-property correlations in these materials during pyrolysis, but the extreme laboratory conditions required to produce C/C composites make it difficult to quantify the properties . This work presents an atomistic modeling methodology to pyrolyze a crosslinked phenolic resin network and track the evolving thermomechanical properties of the skeletal matrix during simulated pyrolysis.
View Article and Find Full Text PDFMater Horiz
January 2025
New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, India.
The complex synthetic approach and utilization of toxic chemicals restrain the commercialization of numerous existing superhydrophobic materials. This article focuses on the development of a halogen-free superhydrophobic material for self-cleaning applications. HMDS-modified MCM-41 is employed as the base material.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Civil and Environmental Engineering Department, University of Houston, 4226 Martin Luther King Blvd, Houston, Texas 77204, United States.
The permeability-selectivity trade-off in polymeric desalination membranes limits the efficiency and increases the costs of reverse osmosis and nanofiltration systems. Ultrathin contorted polyamide films with enhanced free volume demonstrate an impressive 8-fold increase in water permeance while maintaining equivalent salt rejection compared to conventional polyamide membranes made with -phenylenediamine and trimesoyl chloride monomers. The solution-based molecular layer-by-layer (mLbL) deposition technique employed for membrane fabrication sequentially reacts a shape-persistent contorted diamine monomer with a trimesoyl chloride monomer, forming highly cross-linked, dense polyamide networks while avoiding the kinetic and mass transfer limitations of traditional interfacial polymerization.
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