Multifunctional Gas and pH Fluorescent Sensors Based on Cellulose Acetate Electrospun Fibers Decorated with Rhodamine B-Functionalised Core-Shell Ferrous Nanoparticles

Abstract

ferrous core-shell nanoparticles consisting of a magnetic γ-fe 2 o 3 multi-nanoparticle core and an outer silica shell have been synthesized and covalently functionalized with Rhodamine B (RhB) fluorescent molecules (γ-fe 2 o 3 /Sio 2 /RhB NPs). The resulting γ-fe 2 o 3 /Sio 2 /RhB nps were integrated with a renewable and naturally-abundant cellulose derivative (i.e. cellulose acetate, CA) that was processed in the form of electrospun fibers to yield multifunctional fluorescent fibrous nanocomposites. The encapsulation of the nanoparticles within the fibers and the covalent anchoring of the RhB fluorophore onto the nanoparticle surfaces prevented the fluorophore's leakage from the fibrous mat, enabling thus stable fluorescence-based operation of the developed materials. These materials were further evaluated as dual fluorescent sensors (i.e. ammonia gas and pH sensors), demonstrating consistent response for very high ammonia concentrations (up to 12000 ppm) and fast and linear response in both alkaline and acidic environments. The superparamagnetic nature of embedded nanoparticles provides means of electrospun fibers morphology control by magnetic field-assisted processes and additional means of electromagnetic-based manipulation making possible their use in a wide range of sensing applications. Nanoparticle-based systems containing more than one functional components represent an active research field having a great potential in numerous technological applications 1. Among others, magnetic core-shell nanoparticles offer new opportunities in the biomedical field, catalysis and sensing 2-10. In particular, fluorescent-functionalized silica-coated core-shell magnetic nanoparticles attract high attention in imaging and sensing applications. In such multifunctional nanomaterials the fluorescent dye can be covalently anchored either onto the silica surface or doped into the matrix of the silica shell 2,3,11-13. Electrospinning has been one of the most versatile methods employed for generating nano-and microfibers 14-16. Its simplicity, scalability and high versatility renders this method very attractive in many scientific fields. Electrospun polymer-based organic-inorganic fibrous nanocomposites have been developed by many research groups and further evaluated in various fields including biomedicine 17-19 , catalysis 20-22 , sensing 23 , energy 24,25 and environmental protection 26-29. However, only a few examples appear to date on the fabrication of nanocomposite electrospun fibers with embedded core-shell ferrous nanoparticles 30,31. In one such example, core-shell Fe/ FeO nanoparticles have been incorporated within polyimide fibers aiming to produce fibrous nanocomposites

Impulsivity, Lack of Premeditation, and Debts in Online Gambling Disorder

“…According to the UPPS-P model, lack of premeditation is the tendency to make decisions without considering their consequences ( 19 ). It is known that in people with GD, lack of premeditation is related to unfavorable decision-making ( 46 ), such as an inability to identify the possible negative financial problems due to gambling ( 18 ). This could be a potential explanation for the lower premeditation scores obtained in online gamblers than offline gamblers in the current sample.…”

“…In line with these findings, high impulsivity has been pronounced in people with GD as opposed to healthy controls ( 17 ). There are many models that have tried to explain impulsivity and its complex nature ( 14 , 18 ). The UPPS-P Impulsive Behavior Scale, developed by Whiteside and Lynam ( 19 ) and modified by Cyders et al ( 20 ) measures five personality dimensions that contribute to impulsive behavior.…”

Standardization of esophageal adenocarcinoma in vitro model and its applicability for model drug testing

“…Then, an additional 10-nm-thick layer of dye-free silica was deposited on the surface of fluorescent silica coating. Estimated mean weight of iNANO-RITC nanoparticles is 4.1 * 10 –15 g 51 , 52 . After 1 wk in culture, 200 μL of 100 μg/mL iNANO RITC diluted in culture medium was added to the apical compartment for 3 h, whilst 800 μL of fresh culture medium was added to the basal compartment.…”

Smart textiles and wearable technologies – opportunities offered in the fight against pandemics in relation to current COVID-19 state

“…They found out that the breathability mainly depended on the porosity and pore length. So electrospinning, apart from melt blowing [73], is another crucial process in fiber manufacturing that is already extensively used in the filtration industry [74][75][76][77][78] and many types of sensors [79]. Electrospinning belongs to electrohydrodynamic processes [80][81][82] involving the polymer solution jetting controlled with the electrostatic forces [83][84][85][86].…”