Adsorption behaviour of molecularly imprinted-beta-cyclodextrin polymers prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization for selective recognition of benzylparaben

Molecularly imprinted polymers (MIPs) are kinds of powerful materials with promising selective molecule recognition abilities. However, the conventional MIPs have relatively low binding capacity. In order to improve this characteristic of MIPs, the modification monomer based on β-cyclodextrin (β-CD) and the essential of reversible addition�fragmentation chain transfer (RAFT) polymerization process were studied to generate potential MIPs. The study focuses on the characterization and adsorption behaviour of MIPs for selective recognition of benzylparaben (BzP) analyte. The potential of β-CD in MIP was investigated by synthesizing a reversible addition-fragmentation chain transfer molecularly imprinted methacrylic acid functionalized β-cyclodextrin polymer; RAFT�MIP(MAA-β-CD) based on methacrylic acid functionalized β-cyclodextrin (MAA-β-CD) monomer, which was then compared to a reversible addition-fragmentation chain transfer molecularly imprinted methacrylic acid polymer; RAFT-MIP(MAA) synthesized without β-CD. Both MIPs were prepared by the RAFT polymerization process in bulk polymerization method. The resulting MIPs were characterized using Fourier Transform Infrared Spectroscopy (FTIR), Field Scanning Electron Microscope (FESEM) and Brunauer-Emmett-Teller (BET) analysis. The batch adsorption study that includes studying of the pH, kinetic, isotherm and thermodynamic was conducted. The essential of RAFT polymerization on MIP was studied by comparing RAFT-MIP(MAA-β-CD) with the molecularly imprinted methacrylic acid functionalized β-cyclodextrin polymer; MIP(MAA-β-CD) was synthesized without RAFT agent, and characterized by using FTIR, elemental analysis, FESEM and BET. The binding experiments demonstrated that the RAFT-MIP(MAA-β-CD) has a higher binding capacity and higher accessibility compared to RAFT-MIP(MAA) and MIP(MAA-β-CD) for selective of BzP, respectively. The β-CD and RAFT polymerization process improved the MIP’s physical properties and iv enhanced its recognition capacity, thus affecting the adsorption behaviour of RAFT�MIP(MAA-β-CD). The effects of RAFT polymerization process were also investigated by a reversible addition-fragmentation transfer molecularly imprinted hydroxylethyl methacrylate functionalized β-cyclodextrin polymer; RAFT-MIP(HEMA-β-CD). The RAFT-MIP(HEMA-β-CD) was synthesized based on the hydroxylethyl-methacrylate functionalized β-cyclodextrin (HEMA-β-CD) monomer and was prepared by the RAFT polymerization process in bulk polymerization method. The molecularly imprinted hydroxylethyl-methacrylate functionalized β-cyclodextrin polymer; MIP(HEMA-β-CD) without a RAFT agent was synthesized as comparison. A similar study to RAFT�MIP(MAA-β-CD) had also been carried out for RAFT-MIP(HEMA-β-CD).The effects of RAFT polymerization on RAFT-MIP(HEMA-β-CD) were contrasted with RAFT�MIP(MAA-β-CD). The compact and non-porous morphology of RAFT-MIP(HEMA-β�CD) reduces its binding capacity performance compared to MIP(HEMA-β-CD). Thus, this directly affected the RAFT-MIP(HEMA-β-CD) adsorption behaviour towards BzP. It was resulted that the RAFT polymerization had not improved the synthesis of RAFT�MIP(HEMA-β-CD). Careful choice of RAFT agent and monomer is essential in realizing good control over the RAFT-MIP polymerization process, and generating potential MIP

Triton X-100β-Cyclodextrin cloud point extraction for removal of phenol using different of sodium salts as inducing phase separation agent

A simple and low-cost cloud point extraction (CPE) method was developed for the removal of phenol in water samples prior to its spectrophotometric detection. Two CPE methods; CPE-(TX/βCD)-NaOH and CPE-(TX/βCD)-Na2CO3 were developed based on Triton X-100/β-cyclodextrin (TX-100/β-CD) using electrolytes of sodium hydroxide (NaOH) and sodium carbonate (Na2CO3), respectively as inducing phase separation agents. The effects of parameters; electrolytes, surfactant, β-CD, and analyte concentrations, temperature, incubation time, and pH were evaluated in the context of extracting phenol from an aqueous media. Under optimized conditions, the CPE-(TX-βCD)-NaOH was selected to extract phenol from real water samples due to its superior performance vis-à-vis the CPE-(TX-βCD)-Na2CO3. The calibration curve was linear in the range of 1.0 mg L-1 to 3.0 mg L-1 of phenol, with a regression coefficient of 0.9855. The extraction efficiency in spiked and without spiked phenol in real water samples was in the range of 91.9 - 116.1 %. The results confirmed that the developed method can be applied satisfactorily to detect the presence of phenol in real water samples

Synthesis and evaluation of green magnetic mesoporous molecularly imprinted polymers for adsorption removal of parabens from cosmetic samples

Parabens are chemicals that are frequently used as preservatives in numerous cosmetic products. In recent years, the safety concern over these compounds has grown due to their endocrinedisrupting activity. In this research, a novel green magnetic molecularly imprinted polymer (GMMIP) was synthesised using propylparaben as a template and then applied as an adsorbent to selectively recognise and remove parabens from cosmetic samples. The green strategies were introduced by using Persicaria odorata or Kesum leaf extract as a reducing agent to synthesise green magnetic nanoparticles (MNP) as a magnetic core, and deep eutectic solvent (DES) has been designed as an environmentally friendly functional monomer that was used in the preparation of GMMIP. The GMMIP was characterised using Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and BrunauerEmmett-Teller (BET). The results of FESEM and BET indicated that the GMMIP exhibited an irregular spherical shape and mesoporous characteristics with a pore size of 17.74 nm. The adsorption pH, kinetics, isotherms, and thermodynamics parameters were performed to investigate the interactions that take place between GMMIP and propylparaben. The adsorption processes appeared to best fit the pseudo-second-order kinetic and Freundlich isotherm models at an optimum pH of 12. Findings from a thermodynamics study revealed the adsorption process was exothermic, spontaneous, and more favourable at 298 K. The optimised GMMIP was applied as an adsorbent to remove the parabens from cosmetic samples. When compared to methylparaben and ethylparaben, the GMMIP had the highest selectivity and effectively removed propylparaben, with recoveries ranging from 75.6% to 113.3%. It was found that the limits of detection (LOD) and quantification (LOQ) were between 0.03 and 0.05 mg/L and 0.11 and 0.16 mg/L, respectively. The synthesised GMMIP proved to be a convenient and effective adsorbent to remove parabens from cosmetic products

Preparation and characterization of magnetite (Fe3O4) nanoparticles By Sol-Gel method

The magnetite (Fe3O4) nanoparticles were successfully synthesized and annealed under vacuum at different temperature. The Fe3O4 nanoparticles prepared via sol-gel assisted method and annealed at 200-400ºC were characterized by Fourier Transformation Infrared Spectroscopy (FTIR), X-ray Diffraction spectra (XRD), Field Emission Scanning Electron Microscope (FESEM) and Atomic Force Microscopy (AFM). The XRD result indicate the presence of Fe3O4 nanoparticles, and the Scherer`s Formula calculated the mean particles size in range of 2-25 nm. The FESEM result shows that the morphologies of the particles annealed at 400ºC are more spherical and partially agglomerated, while the EDS result indicates the presence of Fe3O4 by showing Fe-O group of elements. AFM analyzed the 3D and roughness of the sample; the Fe3O4 nanoparticles have a minimum diameter of 79.04 nm, which is in agreement with FESEM result. In many cases, the synthesis of Fe3O4 nanoparticles using FeCl3 and FeCl2 has not been achieved, according to some literatures, but this research was able to obtained Fe3O4 nanoparticles base on the characterization results

Quality analysis of meats using FTIR spectroscopy, colour spectrophotometer, texture analyser and physical image analysis

Assessment methods of meat such as physicochemical analyses and microbial techniques are laborious and time-consuming. A rapid and non-destructive quality analysis method of meat is needed and important to satisfy consumer demand. This study aims to implement FT-IR spectroscopy, colour spectrophotometer, texture analyser and physical image analysis to analyse the quality of raw, boiling and roasting meat. The FT-IR analysis revealed the functional group for proteins, triglycerides, fatty acids and carbohydrates with different intensities mostly focused at 3300 cm-1, 2967 cm-1, 1639 cm-1, 1546 cm-1, 1453 cm-1. Colour parameters showed slight alterations and partial degradation of some proteins in meat was observed. L*, a* and b* for raw meats decreased, L* and b* for boiled and roasted meats increased, and a* decreased. The texture analysis shows significant different tenderness of meats and even cooking methods. Tenderness of raw meats decreased while the cooked meats increased from the first until the fifth day. The image analysis shows no significant changes in the meat textural surface. The findings show that the quality of cooked meats was better than raw meats. The assessment methods applied can evaluate the quality of meats and provide additional information on the physical changes of meat composition and structure

Synthesis of PANI/Iron (II, III) Oxide Hybrid Nanocomposites Using Sol-Gel Method

A polyaniline/iron (II,III) (PANI/Fe₃Oâ‚„) hybrid nanocomposites were synthesized using a sol-gel method. The characterization of PANI/Fe₃Oâ‚„ hybrid nanocomposites were studied by Fourier transforms infrared spectroscopy with attenuated total reflectance (FTIR-ATR), multimeter, and permanent magnet. The FTIR result indicated that the PANI/Fe₃Oâ‚„ hybrid nanocomposites were successfully synthesized due to the chemical interaction was occurred by comparing a spectra of Fe₃Oâ‚„, polyaniline (PANI) and PANI/Fe₃Oâ‚„ hybrid nanocomposites. The electrical conductivity and magnetic properties of PANI/Fe₃Oâ‚„ hybrid nanocomposites were clearly performed using a multimeter and a permanent magnet, respectively. Application of external field to the sample have resulted 0.1 mV and 0.001 V DC readings for conductivity. While a Fe₃Oâ‚„ in the hybrid nanocomposites shows attractions to the permanent magnet, thus producing a magnetic field.Â

Evaluation of Extra Virgin Olive Oil Adulteration with Edible Oils using ATR-FTIR Spectroscopy

Extra virgin olive oil (EVOO) is categorized as expensive oil due to high-quality nutritional value. Unfortunately, EVOO is easily adulterated with other low-quality edible oils. Therefore, this study was done to differentiate and analyze the adulteration of EVOO with other edible oils using Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy. The study was used several edible oils included canola oil, corn oil, sunflower oil, and soybean oil as an adulterant for EVOO. The adulterant EVOO samples were prepared by mixing with dissimilar concentrations of the solely edible oils (20 %, 40 %, 60 % and 80 % (v/v)). The main functional groups of EVOO and other edible oils are O-H, C-H, C=C and C=O groups were assigned around 3500 cm-1, 2925 cm-1, 3006 cm-1 and 1745 cm-1 wavenumbers, respectively. From the comparison of EVOO and other adulterant edibles oil spectra, it showed that the EVOO has the lowest absorbance intensity at around 3006 cm-1 represented double bond which is closely related to the composition of oil sample. The adulteration of EVOO was evaluated by analysing the changes in the absorbance based on the linear regression analysis graph of the bands at 3006 and 2925 cm-1 and the limit of detection (LOD) was measured. The graph of A3008/A2925 with good relative coefficients (R2) and lower LOD is more favourable than the linear regression graph of A3006 versus percentage of edible oils added in EVOO. This study showed that ATR-FTIR spectroscopy is a convenient tool for analysing the adulteration of EVOO

Synthesis of PANI/Iron (II, III) oxide hybrid nanocomposites using SolGel method

A polyaniline/iron (II,III) (PANI/Fe₃O₄) hybrid nanocomposites were synthesized using a sol-gel method. The characterization of PANI/Fe₃O₄ hybrid nanocomposites were studied by Fourier transforms infrared spectroscopy with attenuated total reflectance (FTIR-ATR), multimeter, and permanent magnet. The FTIR result indicated that the PANI/Fe₃O₄ hybrid nanocomposites were successfully synthesized due to the chemical interaction was occurred by comparing a spectra of Fe₃O₄, polyaniline (PANI) and PANI/Fe₃O₄ hybrid nanocomposites. The electrical conductivity and magnetic properties of PANI/Fe₃O₄ hybrid nanocomposites were clearly performed using a multimeter and a permanent magnet, respectively. Application of external field to the sample have resulted 0.1 mV and 0.001 V DC readings for conductivity. While a Fe₃O₄ in the hybrid nanocomposites shows attractions to the permanent magnet, thus producing a magnetic field

Optimisation and evaluation of zinc in food samples by cloud point extraction and spectrophotometric detection / Nurul Azwa Mohd Azizi … [et al.]

The cloud point extraction (CPE) method was developed to determine the zinc prior to Ultraviolet-visible (UV-Vis) spectrophotometry detection. Triton X-100 was applied as extractant based on the complexation reaction of Zn(II) ions with ethylenediaminetetraacetic acid (EDTA). Under optimal conditions, the CPE was used to determine the concentration of zinc in canned food samples. The amounts of zinc found in the food samples were in the range of 0.005-0.007 mg/L with relative standard deviation (RSD) of < 8 %. This confirmed that the proposed CPE method is suitable for the determination of zinc in food samples, indicating the concentration of zinc was within the permissible limit

Optimization and determination of Tartrazine by Green Tween-20 cloud point extraction for food samples / Nurulhazirah Mohd Nasir... [et al.]

A simple and low-cost cloud point extraction (CPE) method was developed for the determination of tartrazine in food samples by spectrophotometry detection at a wavelength 427.5 nm. The CPE was performed by utilizing Tween-20 and sodium carbonate (Na 2 CO 3 ) as extractant and separation accelerator, respectively. Factors that influenced CPE such as surfactant and salt concentrations, pH and temperature were optimized in the context of extracting tartrazine from aqueous media. Under an optimal condition, the proposed CPE was applied for the determination of tartrazine in sweets and concentrated syrup juice, which represented food samples. A CPE-UV-Vis method showed linear calibration within the range of 1-12 mg L -1 of tartrazine with a regression coefficient was 0.9957. The limit of detection (LOD) and limit of quantification (LOQ) of the method were 0.88 mg L -1 and 2.96 mg L -1 , respectively. The relative standard deviation (RSD) was found to be < 3.00 %. The amount of tartrazine found in food samples was 1.22-6.12 mg L -1 . The results showed that the proposed CPE method was applicable for the determination of tartrazine in food samples and the tartrazine content in the food samples was permitted according to the guidelines from the European Food Safety Authority (EFSA)