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1.
Environ Monit Assess ; 196(6): 582, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806872

RESUMO

IoT is a game-changer across all fields, including chemistry. Embracing sustainable practices and green chemistry, the miniaturization and automation of systems, and their integration into IoT is key to achieving these principles, as a rising trend with momentum. Particularly, IoT and analytical chemistry are linked in the rapid exchange of analytical data for environmental, industrial, healthcare, and educational applications. Meanwhile, cooperation with other fields of science is evident, and there is a prompt and subjective analysis of information related to analytical systems and methodologies. This paper will review the concepts, requirements, and architecture of IoT and its role in the miniaturization and automation of analytical tools using electronic modules and sensors. The aim is to explore the standards and perspectives of IoT and its interaction with different aspects of analytical chemistry. Additionally, it aimed to explain the basics and applications of IoT for chemists, and its relevance to different subfields of analytical chemistry, particularly in the field of environmental chemical surveillance. The article also covers updating IoT devices and creating DIY-based degradation devices to enhance the educational aspect of chemistry and reduce barriers to lab facilities and equipment. Lastly, it will explore how IoT is really important and how it's going to significantly impact analytical chemistry.


Assuntos
Monitoramento Ambiental , Internet das Coisas , Miniaturização , Monitoramento Ambiental/métodos
2.
Acta Chim Slov ; 69(2): 322-330, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35861066

RESUMO

The quality of edible oils is significantly affected by autoxidation of lipids, which alters their flavor and nutritional quality through production of toxic materials like aldehydes (an important class of oil deterioration markers). Herein, an amino-silica nanospheres/polypyrrole (ASNS/PPy) nanocomposite sorbent was synthesized and used as the fiber coating for headspace solid-phase microextraction (HS-SPME) of aldehydes in edible oils, followed by gas chromatography (GC) separation and determination. Amino-silica nanoparticles were prepared by an amended Stöber method and composited with polypyrrole during its electropolymerization on the surface of a platinized stainless-steel fiber. The synergy between in-situ electropolymerization and rough surface of the platinized metal substrate created a durable fiber coating with unique uniformity, cohesiveness, and adsorption properties. The synthesized nanocomposite was characterized using Fourier transform infrared spectroscopy and scanning electron microscopy techniques. The performance of the prepared fiber was optimized by investigating the affecting variables including extraction temperature and time, stirring rate, and desorption conditions. The obtained limits of detection for hexanal and heptanal in sunflower oil were 0.005-0.009 µg mL-1. The prepared fiber exhibited excellent repeatability and reproducibility with the intra-fiber and inter-fiber relative standard deviations in the ranges of 3.9-8.8% and 7.3-15.1%, respectively. The proposed HS-SPME-GC strategy was successfully applied for the analysis of aldehydes in commercial edible oil samples.


Assuntos
Nanosferas , Polímeros , Aldeídos , Nanosferas/análise , Óleos , Polímeros/análise , Polímeros/química , Pirróis/análise , Pirróis/química , Reprodutibilidade dos Testes , Dióxido de Silício/química , Microextração em Fase Sólida/métodos
3.
Anal Bioanal Chem ; 413(12): 3243-3251, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33751164

RESUMO

Recent development of portable three-dimensional printed (3DP) microfluidic-based devices has provided a new horizon for real-time field analysis of environmental pollutants. Smartphones with the possibility of launching different software, sensing, and grading color intensity, as well as capability of sending/receiving data through the internet have made this technology very promising. Here, a novel smartphone-based 3DP microfluidic device is reported that uses an image-based colorimetric detection method for the analysis of uranium in water samples, based on the complex formation of uranyl ions with Arsenazo III. The microfluidic device consists of two horizontal channels, separated by an integrated porous membrane, and was printed in a single run using a transparent photopolymer. It enables the operator to see the internal parts and the color change visually, as well as enables the operator to take images and record the color intensity using a smartphone. In each 3DP run, 220 devices are fabricated in 1.5 h (~ 25 s per device) at an estimated price of $2.5 per device. A Box-Behnken design (BBD) was utilized for the optimization of experimental conditions. The calibration curve was linear within 0.5-100 µg mL-1 (R2 > 0.9925) of uranium analysis. The total time of each experiment was approximately 8 min. The 3DP device was successfully employed for the recovery and determination of uranium in spiked natural water samples.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33296831

RESUMO

Recent developments on self-propelled microdroplets, moving controllably in response to an external stimulus like chemical, electrical, or magnetic field, have opened a new horizon for smart drug delivery investigations. On the other hand, the new achievements in 3D printing technology has provided a promising option for the fabrication of microfluidic devices, which is an unrivalled platform for in-vitro drug delivery studies. By synergizing the features of chemotaxis, 3D printing, and microfluidic techniques a new approach was introduced to deliver the drug to targeted sites with a well-controlled method and a reasonable speed. A self-propelled ionic liquid ([P6,6,6,14][Cl]) microdroplet, as the drug carrier, was utilised for the targeted delivery of epirubicin anticancer drug within an integrated drug delivery microfluidic system. The asymmetric diffusion of [P6,6,6,14]+ ion from the microdroplet into an aqueous solution with chloride gradient concentration (created under an external electrical field) caused the microdroplet to move. The spatial and temporal position of the moving microdroplet could be controlled by changing the magnitude and polarity of the external electrical field. A piece of hollow-fiber, fixed next to the anode, was filled with phosphate buffer (as the receptor) and used to remove the drug from the carrier. The receptor solution was then taken and injected into a HPLC system for quantification of the released drug. After one-at-a-time optimization of the channel geometry and electrolyte concentration, the experimental variables affecting the drug loading including contact time, pH, and volume of carrier were optimized via a central composite design (CCD) approach.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Epirubicina , Dispositivos Lab-On-A-Chip , Quimiotaxia , Cromatografia Líquida de Alta Pressão , Epirubicina/análise , Epirubicina/química , Epirubicina/farmacocinética , Desenho de Equipamento , Líquidos Iônicos/química , Impressão Tridimensional
5.
Anal Chim Acta ; 1083: 119-129, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31493802

RESUMO

Polyaniline silica (Silica/PANI) organic-inorganic nanocomposite was synthesized by combining electrospinning and in-situ polymerization processes. This strategy prevented the aggregation of PANI during the polymerization and led to higher synthesis's yield and more uniformity of the produced composite. The structure and morphology of the nanocomposite was characterized using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and X-ray diffraction (XRD) techniques. The prepared nanocomposite was then packed inside a stain-steel needle and evaluated as a needle trap device (NTD), for simultaneous headspace extraction of polycyclic aromatic hydrocarbons (PAHs) and benzene, toluene, ethylbenzene, and xylenes (BTEX) in polluted soil samples, before GC-FID analysis, as a low-cost and robust detector. Response surface methodology (RSM) involving Box-Behnken design (BBD) was implemented to evaluate the effective experimental variables and subsequent introduction of a multiple function to describe the experimental conditions for the extraction of the analytes. Wide calibration plots (1-2000 ng g-1 for BTEX and 0.2-2000 ng g-1 for PAHs) with acceptable linearity (R2 > 0.99) were obtained under the optimal conditions. The limits of detection were found to be 0.02-0.1 ng g-1for BTEX and 0.001-0.01 ng g-1 for PAHs. The calculated standard deviations were 7.3-13.2% (n = 6). The developed NTD-GC-FID method was successfully applied for the extraction and determination of PAHs and BTEX in contaminated soil samples.

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