A new method for the preparation of MgAl layered double hydroxide-copper metal-organic frameworks structures: application to electrocatalytic oxidation of formaldehyde.

In this research, we present a novel design protocol for the in-situ synthesis of MgAl layered double hydroxide-copper metal-organic frameworks (LDH-MOFs) nanocomposite based on the electrocoagulation process and chemical method. The overall goal in this project is the primary synthesis of para-phthalic acid (PTA) intercalated MgAl-LDH with Cu (II) ions to produce the paddle-wheel like Cu-(PTA) MOFs nanocrystals on/in the MgAl-LDH structure. The physicochemical properties of final product; Cu-(PTA) MOFs/MgAl-LDH, were characterized by the surface analysis and chemical identification methods (SEM, EDX, TEM, XRD, BET, FTIR, CHN, DLS, etc.

An amplified electrochemical sensor employing one-step synthesized nickel-copper-zinc ferrite/carboxymethyl cellulose/graphene oxide nanosheets composite for sensitive analysis of omeprazole.

In this work, a signal amplification strategy was designed by the fabrication of a highly sensitive and selective electrochemical sensor based on nickel-copper-zinc ferrite (NiCuZnFeO)/carboxymethyl cellulose (CMC)/graphene oxide nanosheets (GONs) composite modified glassy carbon electrode (GCE) for determination of omeprazole (OMP). The one-step synthesized NiCuZnFeO/CMC/GONs nanocomposite was characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy and X-ray diffraction techniques. Then, the NiCuZnFeO/CMC/GONs/GCE was applied to study the electrochemical behavior of the OMP.

3D printed solid phase microextraction scaffolds as novel tool for sample preparation; application in antifungal drugs analysis.

3D printed solid phase microextraction scaffolds as a novel sorbent were introduced for the extraction of antifungal drugs in wastewater and human plasma prior to their determination by HPLC-UV. The designed adsorbent was prepared as cubic scaffolds using fused deposition modeling (FDM) 3D printer and Polylactic acid (PLA) filament. Scaffold surface was chemically modified using alkaline ammonia solution (Alkali treatment).

A sensitive nanocomposite design via carbon nanotube and silver nanoparticles: Selective probing of Emedastine Difumarate.

In this study, a novel and sensitive nanocomposite of carboxylate-functionalized multiwalled carbon nanotube (COOH-fMWCNT) and silver nanoparticles (AgNPs) was fabricated and used to modify a glassy carbon electrode (GCE) by a simple drop casting method. Modified electrode was then applied for selective determination of emedastine difumarate (EDD). The COOH-fMWCNT/AgNPs nanocomposite was characterized by electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and cyclic voltammetry (CV).

NiCo alloy nanoparticles electrodeposited on an electrochemically reduced nitrogen-doped graphene oxide/carbon-ceramic electrode: a low cost electrocatalyst towards methanol and ethanol oxidation.

In this work, nickel-cobalt alloy nanoparticles were electrodeposited on/in an electrochemically reduced nitrogen-doped graphene oxide (ErN-GO)/carbon-ceramic electrode (CCE) and the resulting nanocomposite (NiCo/ErN-GO/CCE) was evaluated as a low cost electrocatalyst for methanol and ethanol electrooxidation. Field-emission scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy were used for the physical characterization of the electrocatalyst. To study the electrochemical behavior and electrocatalytic activity of the prepared electrocatalyst towards the oxidation of methanol and ethanol in alkaline media, cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy were utilized.

Application of surface molecular imprinted magnetic graphene oxide and high performance mimetic behavior of bi-metal ZnCo MOF for determination of atropine in human serum.

Herein, high performance peroxidase-like activity of zinc and cobalt bi-metal metal-organic framework (ZnCo MOF) is reported and applied for the sensitive measurement of atropine. ZnCo MOF was synthesized by the reaction of 2-methylimidazole with Zn and Co (II) cations in aqueous media. The colorimetric and fluorometric experiments were applied to investigate the catalytic activity of obtained MOF, using o-phenylenediamine (OPD) and terephthalic acid (TA) peroxidase substrates, respectively.

Sensitive biosensing of organophosphate pesticides using enzyme mimics of magnetic ZIF-8.

Development of a sensitive detection method for the reliable screening of widely used organophosphorus (OP) toxins is a crucial request to control their side-effects. Herein, a novel fluorometric assay based on the acetylcholinesterase (AChE) inhibited enzymatic activity and the new peroxidase-like FeO nanoparticles@ZIF-8 composite (FeO NPs@ZIF-8) was developed for the determination of OPs. Magnetic FeO NPs were encapsulated into ZIF-8 and the high mimetic activity of produced composite was assessed on the oxidation of substrates.

Ultrasensitive immunoassay of glycoprotein 125 (CA 125) in untreated human plasma samples using poly (CTAB‑chitosan) doped with silver nanoparticles.

CA 125 is a Mucin glycoprotein and its concentration in human serum correlates with a woman's risk of developing ovarian cancer and also indicates response to therapy in diagnosed patients. Accurate detection of this large, complex protein in patient biofluids is of great clinical relevance. In this work, an innovative immunoassay for quantitation of CA 125 based on signal amplification strategy was proposed.

Visual detection of peroxide-based explosives using novel mimetic Ag nanoparticle/ZnMOF nanocomposite.

A simple and selective colorimetric method for the detection of perilous peroxide explosives was developed using the peroxidase mimetic activity of silver nanoparticles/flake-like zinc metal-organic framework nanocomposite (Ag@ZnMOF). The synthesis of Ag@ZnMOF contained the formation of silver nanoparticles (AgNPs) inside the fine pores of Zn metal-organic framework (ZnMOF). High reactive AgNPs as well as great surface area of MOFs provided a synergetic and high improved catalytic activity for the composite which was studied as a peroxidase mimic in hydrogen peroxide (HO)-based oxidations.

Motor Oil Classification Using Color Histograms and Pattern Recognition Techniques.

Motor oil classification is important for quality control and the identification of oil adulteration. In this work, we propose a simple, rapid, inexpensive and nondestructive approach based on image analysis and pattern recognition techniques for the classification of nine different types of motor oils according to their corresponding color histograms. For this, we applied color histogram in different color spaces such as red green blue (RGB), grayscale, and hue saturation intensity (HSI) in order to extract features that can help with the classification procedure.

Mimetic Ag nanoparticle/Zn-based MOF nanocomposite (AgNPs@ZnMOF) capped with molecularly imprinted polymer for the selective detection of patulin.

Here, Ag nanoparticle/flake-like Zn-based MOF nanocomposite (AgNPs@ZnMOF) with great peroxidase-like activity was applied as an efficient support for molecularly imprinted polymer (MIP) and successfully used for selective determination of patulin. AgNPs@ZnMOF was simply synthesized by creating Ag nanoparticles (Ag NPs) inside the nano-pores of flake-like (Zn)MOF. The high surface area of MOF remarkably improved the catalytic activity of Ag NPs which was assessed by fluorometric, colorimetric and electrochemical techniques.

Synthesis and characterization of graphene quantum dots/CoNiAl-layered double-hydroxide nanocomposite: Application as a glucose sensor.

In the present work, a novel nanocomposite based on the graphene quantum dots and CoNiAl-layered double-hydroxide was successfully synthesized by co-precipitation method. To achieve the morphological, structural and compositional information, the resulted nanocomposite was characterized by scanning electron microscopy X-ray diffraction, thermal gravimetric analysis, Fourier transform infrared spectroscopy, and photoluminescence. Then, the nanocomposite was used as a modifier to fabricate a modified carbon paste electrode as a non-enzymatic sensor for glucose determination.

A novel and facile synthesis of carbon quantum dots via salep hydrothermal treatment as the silver nanoparticles support: Application to electroanalytical determination of H2O2 in fetal bovine serum.

A simple, low-cost, and green process was used for the synthesis of carbon quantum dots (CQDs) through the hydrothermal treatment of salep as a novel bio-polymeric carbon source in presence of only pure water. The silver nanoparticles (AgNPs) were embedded on the surface of CQDs by ultra-violate (UV) irradiation to the CQDs and silver nitrate mixture solution. The as-synthesized CQDs and AgNPs decorated CQDs nanohybrid (AgNPs/CQDs) were characterized by UV-vis and photoluminescence spectroscopy, Fourier transform-infrared spectroscopy, transmission electron microscopy, atomic force microcopy, X-ray diffraction, and field emission scanning electron microscopy.

Simultaneous determination of codeine and caffeine using single-walled carbon nanotubes modified carbon-ceramic electrode.

In the present paper, the simultaneous determination of codeine (CO) and caffeine (CF) is described by the use of single-walled carbon nanotubes modified carbon-ceramic electrode (SWCNT/CCE); prepared via a simple and rapid method. The results show that the SWCNT/CCE exhibits excellent electrochemical catalytic activity toward the oxidation of these compounds with respect to the bare CCE and offers two anodic peaks at 1.05 and 1.

Differential pulse voltammetric simultaneous determination of acetaminophen and ascorbic acid using single-walled carbon nanotube-modified carbon-ceramic electrode.

Single-walled carbon nanotube-modified carbon-ceramic electrode (SWCNT/CCE) was employed for the simultaneous determination of acetaminophen (APAP) and ascorbic acid (AA). The SWCNT/CCE displayed excellent electrochemical catalytic activities toward APAP and AA oxidation compared with bare CCE. In the differential pulse voltammetry technique, both AA and APAP gave sensitive oxidation peaks at -62 and 302 mV versus saturated calomel electrode, respectively.