Metal-organic framework functionalized with deep eutectic solvent for solid-phase extraction of Rhodamine 6G in water and cosmetic products.

An NH2 -MIL-53(Al)-DES(ChCl-Urea) nanocomposite was synthesized for extraction and determination of Rhodamine (Rh) 6G from environmental and cosmetic samples. The deep eutectic solvent (DES) was prepared by mixing choline chloride and urea in a mole ratio of 1:2. NH2 -MIL-53(Al)-DES(ChCl-Urea) nanocomposite was synthesized using the impregnation method at a ratio of 60:40 (w/w). The optimum conditions were determined after NH2 -MIL-53(Al)-DES(ChCl-Urea) characterization was performed. The optimum conditions were determined as pH 8, adsorbent amount of 15 mg, total adsorption-desorption time of 6 min, and enrichment factor of 20. The recovery values of the solid-phase extraction method for water and cosmetic samples under optimum conditions were between 95% and 106%. NH2 -MIL-53(Al)-DES(ChCl-Urea) nanocomposite was an economically advantageous adsorbent because of its reusability of 15 times. All analyses were performed using the ultraviolet-visible spectrophotometer. The linear range, limit of detection, and limit of quantification of the method were 100-1000, 9.80, and 32.68 µg/L, respectively. The obtained results showed that the synthesized nanocomposite is a suitable adsorbent for the determination of Rh 6G in water and cosmetic samples. The real sample applications were verified with the high-performance liquid chromatography system.

Sample Preparation Methods for Metal Containing Pesticides in Food and Environmental Samples.

Metal-containing pesticides are used in many areas for purposes such as harvest efficiency and keeping pests away from the vegetable environment. Metal-containing pesticides are in the form of dithiocarbamate complexes and are named differently according to the type of metal they contain and are used for different purposes. Since the presence of these pesticides even at residue level threatens human and environmental health, their determination at trace level is important. In this review, studies on the determination of metal-containing dithiocarbamate pesticides in different matrices are discussed. This review on the analysis of dithiocarbamate pesticides with different techniques will shed light on the studies to be carried out for the determination of these pesticides one by one in different matrices.

A reusable and sensitive electrochemical sensor for determination of Allura red in the presence of Tartrazine based on functionalized nanodiamond@SiO2@TiO2; an electrochemical and molecular docking investigation.

A sensitive and novel electrochemical sensor for the detection of Allura Red (AR) in the presence of tartrazine (TRZ) was fabricated using a screen-printed electrode modified by functionalized nanodiamond covered using silicon dioxide and titanium dioxide nanoparticles (F-nanodiamond@SiO2@TiO2/SPE). Scanning electron microscopy (SEM), brunauer-Emmett-teller (BET), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FT-IR) techniques were performed to characterize the as-synthesized Fnanodiamond@SiO2@TiO2 nanocomposite. The as-fabricated electrode demonstrated two wide dynamic ranges of 0.01-0.12 and 0.12-8.65 µM with a limit of detection (LOD) as low as 1.22 nM. Moreover, the modified electrode exhibits excellent repeatability, reproducibility, reusability, selectivity, and stability with high sensitivity of 44.3 µA µM-1 cm-1, offering good prospects in the simple, cost-effective, and rapid assessment of their total concentration. The successful detection of AR and TRZ, simultaneously and individually in food samples, revealed the applicability of the sensor in the determination of AR and TRZ with satisfactory recovery. Therefore, these advantages provide an excellent possibility for the smart monitoring of AR and TRZ in the future. In the final step, the preferential intercalative binding mode of Allura red with ds-DNA was approved for the first time by a molecular docking study. This study paves the way for engineering highly sensitive DNA biosensors to monitor azo dye compounds by combining the benefits of nanocomposites and valuable information of a molecular docking study.

Determination of propineb in vegetable samples after a coprecipitation strategy for its separation-preconcentration prior to its indirect determination by FAAS.

In the presented work, a coprecipitation method was developed for separation-preconcentration, and determination of trace quantities of propineb in vegetable samples. Propineb was coprecipitated by using Al(OH)3. The zinc contents in complex structure of propineb was determined by flame atomic absorption spectrometry (AAS). The propineb concentration was calculated by using stoichiometric relationship between the zinc and propineb. Several parameters including the amount of aluminum(III) as carrier element and hydroxide concentration and sample volume were examined. The effects of matrix ions were also investigated. The preconcentration factor was calculated as 15. The limit of detection (LOD) value for propineb was calculated as 15.2 µg L-1. The presented coprecipitation procedure was successfully applied to determination of propineb in vegetable samples.

New Trend in the Extraction of Pesticides from the Environmental and Food Samples Applying Microextraction Based Green Chemistry Scenario: A Review.

This review focused on the green microextraction methods used for the extraction of pesticides from the environmental and food samples. Microextraction techniques have been explored and applied in various fields of analytical chemistry since its beginning, as evinced by the numerous reviews published. The success of any technique in science and technology is measured by the simplicity, environmentally friendly, and its applications; and the microextraction technique is highly successive. Deliberations were attentive to studies where efforts have been made to validate the methods through the inter-laboratory comparison study to assess the analytical performance of microextraction techniques against conventional methods. Succinctly, developed microextraction methods are shown to impart significant benefits over conventional techniques. Provided that the analytical community continues to put forward attention and resources into the growth and validation of the microextraction technique, a promising future for microextraction is forecasted.

Ultrasound assisted supramolecular liquid phase microextraction procedure for Sudan I at trace level in environmental samples.

A method based on supramolecular liquid phase microextraction has been developed for the preconcentration and determination of trace levels of Sudan I. 1-decanol and tetrahydrofuran were used as supramolecular solvent components. Trace levels of Sudan I were extracted into the extraction solvent phase at pH = 4.0 Analytical parameters such as pH value, supramolecular solvent volume, ultrasonication, centrifugation, model solution volume, matrix effects have been optimized. The limit of detection and the limit of quantification values for Sudan I were calculated as 1.74 µg L-1 and 5.75 µg L-1, respectively. In order to determine the accuracy of the method, addition and recovery studies were carried out to environmental samples.

Application of magnetic nanomaterials in bioanalysis.

The importance of magnetic nanomaterials and magnetic hybrid materials, which are classified as new generation materials, in analytical applications is increasingly understood, and research on the adaptation of these materials to analytical methods has gained momentum. Development of sample preparation techniques and sensor systems using magnetic nanomaterials for the analysis of inorganic, organic and biomolecules in biological samples, which are among the samples that analytical chemists work on most, are among the priority issues. Therefore in this review, we focused on the use of magnetic nanomaterials for the bioanalytical applications including inorganic and organic species and biomolecules in different biological samples such as primarily blood, serum, plasma, tissue extracts, urine and milk. We summarized recent progresses, prevailing techniques, applied formats, and future trends in sample preparation-analysis methods and sensors based on magnetic nanomaterials (Mag-NMs). First, we provided a brief introduction of magnetic nanomaterials, especially their magnetic properties that can be utilized for bioanalytical applications. Second, we discussed the synthesis of these Mag-NMs. Third, we reviewed recent advances in bioanalytical applications of the Mag-NMs in different formats. Finally, recently literature studies on the relevance of Mag-NMs for bioanalysis applications were presented.