Simple extraction of bisphenol A in beverages and water by membrane-protected liquid phase microextraction

Bisphenol A (BPA) is a xenoestrogen that widely used in manufacture of plastics. Concern is mounting up when the application of BPA is widespread. A simple sample pre-treatment technique termed membrane-protected liquid phase microextraction (MP-LPME) combined with high performance liquid chromatography (HPLC)-fluorescence detection (FD) was developed for the determination of BPA in beverages and environmental water samples. The MP-LPME technique utilized a nylon membrane to hold the extractant (1-octanol) and prevent the extractant from dissolution into sample solution during agitation. Under optimal extraction conditions, the MP-LPME-HPLC-FD demonstrated ultra-trace detection of BPA and insignificant matrix effect extraction with good relative recoveries in the range of 87.1-99.7% from spiked beverage and environmental water samples. The membrane can be re-applied in the MP-LPME after the first usage and offered relative recovery of > 94%. The MP-LPME technique is eco-friendly as it consumes only minute amounts of organic solvent which is supportive to green analysis

Optimization of Extraction Procedure for Determination of Caffeine Residue in Water

Abstract Extraction procedure for determination of caffeine in water with aided experimental design was successfully optimized. Three variables, namely pH sample, flow rate and elution volume were tested during this study using 2 3 full factorial of central composite design. An optimum working condition was suggested at pH sample (6.4), flow rate (1.2 ml/min) and elution volume of caffeine from sorbent is 9.5 ml of methanol. Detection and quantification limits were obtained at 0.02 and 0.25 ng/ml respectively. Good recovery was calculated within the range of 80.9 -93.7 % at three levels of concentration. Repeatability and reproducibility value show this method to be reliable for routine analysis with low RSD < 10 %. Concentration levels of caffeine in real samples were recorded in the range of 0.64 -59.01 ng/ml. Hierarchical cluster analysis grouped all stations into three clusters at D link /D max x 100 < 15. Wastewater discharge from cafeteria or residential area was a solid reason linked to the presence of high caffeine during this study

Removal efficiency for micro-polystyrene in water by the oil-based ferrofluid employ response surface methodology

This research article presents a study on the potential use of oil-based ferrofluid for the efficient removal of microplastics from water. The targeted analyte, micro-polystyrene (micro-PS), was chosen along with palm oil as the carrier liquid. Fourier Transform Infrared (FTIR) analysis was conducted to identify the main peaks in the ferrofluid, including carboxyl group (1542 cm-1), C-H bonding (1022 cm-1), CH2 bonding (2941 cm-1), CH3 bonding (3461 cm-1), C=C bonding (1255 cm-1), and Fe-O (597.34 cm-1). A comprehensive investigation of the synergistic effect of six variables was performed: volume of oil (4-15 mL), weight of magnetite nanoparticles (0.1-0.2 g), stirring rate (132-468 rpm), contact time (3-12 min), pH value of water samples (pH 6-8), and effect on ionic strength (0-16 g/L). Response surface methodology, including 26 -Plackett-Burman and 24 -central composite design, were employed to establish the relationship between the variables. The optimum operational settings proposed by the model were as follows: volume of oil (14.6 mL), weight of magnetite nanoparticles (0.1 g), stirring rate (216 rpm), contact time (3.29 min), pH value of water samples (pH 6-6.5), and effect on ionic strength (16 g/L), resulting in a remarkable removal efficiency of 91.09 ± 0.99%. The method exhibited desirable figures of merit, including a low bias (%RSD) of below 5% and the ability to reuse the ferrofluids for up to five cycles. Additionally, an analytical greenness metric was employed to assess the environmental impact of the sample preparation process, with a green score of 0.69/1.0 (indicating a light green colour). Future work in this field could focus on the scalability of the developed method and its applicability to real-wastewater treatment

Detection of gliclazide in aqueous samples using liquid chromatography/time-of-flight/mass spectrometry

The big challenge for the detection of pharmaceutical residues in water samples is the type of ionization mode in terms of positive or negative ionization which plays an important role to identify and quantify the analytes using liquid chromatography/mass spectrometry. An analytical method was applied to analysis of gliclazide (diabetic drug) in surface water and wastewater from sewage treatment plants and hospitals. The proposed analytical method allows simultaneous isolation and concentration procedure using solid phase extraction (Oasis HLB) prior to separation using high-performance liquid chromatography. The detection and confirmation was achieved by applying time-of-flight analyzer. The limits of quantification were as low as 1.4 ng/L (deionized water), 4 ng/L (surface water), 27 ng/L (hospital influent), 10 ng/L (hospital effluent), 6 ng/L (sewage treatment plant effluent) and 21 ng/L (sewage treatment plant influent), respectively. On average, good recoveries of higher than 87% were obtained for gliclazide in the studied samples. The proposed method successfully determined and quantified gliclazide in surface water and wastewater. The results showed that gliclazide is a persistent compound in sewage treatment effluents as well as in the recipient rivers. Gliclazide was detected in all samples and the highest concentration was 130 ng/L in influent of sewage treatment plant

Data on organochlorine concentration levels in soil of lowland paddy field, Kelantan, Malaysia

The main goal of this research work is to measure the concentration levels of organochlorine residue in soil. The potential health risk of this pollutant on human was also determined. 10 samples were taken from a lowland paddy field situated in Kelantan, Malaysia. Physical parameters namely soil pH, organic carbon content, water content and particle size were identified to evaluate the quality of soil from the agriculture site. Soxhlet extraction and florisil clean-up process were applied to isolate 10 targeted organochlorine compounds prior to the final determination using a gas chromatography-electron capture detector. Soil from the lowland has characteristics such as slightly acidic, low organic carbon content, high water content and texture dominated by the sandy type. Concentration levels of six detected organochlorine pesticides were calculated in µg/kg. Hazard quotient value in all samples was less than the acceptable risk level HQ ≤ 1, thus reflecting the status of soil in the subjected area as unlikely to pose any adverse health effects

Optimization of effervescent tablet-assisted dispersive liquid-liquid microextraction with central composite design for preconcentration of stimulant drug

The extraction efficiency of stimulant drug, namely caffeine, was investigated using a 23 central composite design. The values of optimum extraction condition were set at 468 µL of 1-dodecanol, 1 piece of effervescent tablet, and 22 °C of extraction temperature. An enrichment factor was calculated as 72 for 80 mL water sample. The run time was conducted in less than 6 min using a non-polar C18 column and an isocratic mobile phase (methanol: water of 40:60 (v/v)) at a controlled flow rate of 1 mL min-1. A good linear response was achieved in the range of 0.01-0.50 µg mL-1 (R2 > 0.998). Detection and quantification limits were calculated at 0.009 and 0.015 µg mL-1, respectively. The average recoveries at two spiking concentration levels were within the range of 75-105% with RSD < 2% (n = 3). Real samples namely beverages which contained caffeine and river water were tested using the proposed method, and the results ranged 0.021-0.56 µg mL-1. The eco-scale score and green analytical procedure index confirmed the greenness profile of the proposed method through a calculated score of 88 and has 6 green criteria, respectively

Green and efficient preconcentration of calcium channel blocker drugs in water using effervescence powder in syringe-assisted deep eutectic solvent dispersive liquid-liquid microextraction

Efficient preconcentration techniques are crucial for the analysis of calcium channel blocker drugs such as amlodipine and nifedipine, commonly used for hypertension and heart diseases. This study optimized the preconcentration conditions using CO2 effervescence powder assisted deep eutectic solvent dispersive liquid-liquid microextraction (EP-DLLME). A central composite design with 30 experiments was employed to determine the effects of extraction solvent volume, effervescence powder mass, water sample volume, and pH water. The optimized conditions for EP-DLLME were determined as follows: 500-μL of extraction solvent, 25-mL of water sample, 5 mg of effervescence powder, and pH 8. High-performance liquid chromatography (HPLC) coupled with a diode array detector was utilized for subsequent analysis. The method exhibited good linearity (r2 = 0.996) and low limits of detection and quantification: 1.73 ng/mL and 5.76 ng/mL for amlodipine, and 0.37 ng/mL and 1.23 ng/mL for nifedipine, respectively. The extraction efficiency, evaluated at three concentration levels, resulted in recoveries ranging from 73 % to 98 %. Repeatability analysis showed satisfactory intra-day and inter-day relative standard deviation values: 3.65 % to 8.38 % for amlodipine and 1.9 % to 10.11 % for nifedipine in the intra-day analysis, and 2.46 % to 9.07 % for amlodipine and 2.92 % to 10.7 % for nifedipine in the inter-day analysis. Furthermore, the EP-DLLME method demonstrated environmental sustainability, achieving a total AGREEnness score of 0.68, emphasizing its environmentally friendly nature

Microplastic abundance, distribution, and composition in Sungai Dungun, Terengganu, Malaysia

Scientific documentation on (Microplastics) MPs abundance in Malaysian waters is still limited and not fully understood. In this study, MPs occurrence in Sungai Dungun, Terengganu, Peninsular Malaysia was analysed. Sampling method was based on sieving 200 µm of bulk water to collect surface water samples from five sites in the vicinity of potential source for MP abundance. Characterisation of MPs was accomplished by gravimetric and digital image processing (for quantification and morphology categorisation), and chemical composition identified by attenuated total reflectanceFourier infrared spectroscopy. The range concentration of MPs was 22.8 to 300.8 items/m3 (mean 102.8 item/m3 ). It was recorded that most of the MPs found were black and transparent. The most frequent morphotypes were fibres, followed by fragments. Polypropylene (C3 H6 )n, polyacrylonitrile (C3 H3 N)n and rayon were the dominant polymertypes of MPs analysed in this work. Metals (Pb < As < Mn < Zn < Cu < Fe < Al) found within the MPs reported varied in terms of µg/mL. This study provided new insights into the understanding of MP levels in inland Malaysian freshwater environment

Micro-solid phase extraction of polycyclic aromatic hydrocarbons in water using either C18 or molecularly imprinted polymer membranes: analytical merits and limitations

Sample pre-treatment is often the bottleneck in an analytical process. Due to the drawbacks of conventional sample pre-treatment methods, microextraction utilizing lower amounts of adsorbents and organic solvents are therefore favoured. A micro-solid phase extraction (μ-SPE) technique coupled with gas chromatography-flame ionization detection (GC-FID) was successfully developed for the analysis of selected polycyclic aromatic hydrocarbons (PAHs), namely phenanthrene, fluoranthene, and pyrene, in environmental water. In this study, μ-SPE techniques using C18 and molecularly imprinted polymer (MIP) membranes were optimized, validated, and applied to the analysis of selected PAHs in environmental water samples. The analytical merits were compared, and the two methods were evaluated in terms of linearity, repeatability, and relative recovery. Under the optimal extraction conditions, both μ-SPE techniques using either C18 or MIP membranes as the adsorbents offered comparable ultratrace analysis of the selected PAHs in the range of 0.003 to 0.01 µg L–1. The extraction strength of C18 membranes was superior to that of MIP membranes for the extraction of low molecular weights PAHs from water in the presence of humic acid as a matrix factor. The C18 membranes overcome the non-covalence interaction between PAHs and humic acid and thus achieve better recovery

Multiwalled carbon nanotubes-encapsulated gellan gum membrane for micro-solid phase extraction of selected polycyclic aromatic hydrocarbons in environmental water and beverages

Non-biodegradable plastics are an unresolved issue in solid waste management as recycling them is expensive. This study focused on formulating a biodegradable gellan gum (GG) membrane embedded with multiwalled carbon nanotubes (MWCNTs) as the adsorbent in the micro-solid phase extraction (µ-SPE) of selected polycyclic aromatic hydrocarbons (PAHs), i.e. phenanthrene, fluoranthene, pyrene and benzo[a]pyrene, in environmental water and fruit-juice beverage samples. PAHs quantitation was performed using micro-high-performance liquid chromatography coupled with ultraviolet detection. The MWCNTs GG membrane was fabricated by mixing MWCNTs in a hot GG solution, which was then crosslinked with glutaraldehyde to resist membrane swelling during extraction. Under the optimal extraction conditions, the proposed µ-SPE technique demonstrated good linearity (1–500 µg L−1; correlation coefficient of ≥ 0.9925) and ultra-trace detection limits (10–60 ng L−1). Good relative recoveries in the range of 81.3–114.9% with acceptable relative standard deviations (≤ 9.7%) revealed that matrix effects were insignificant because the MWCNTs-GG membrane-based µ-SPE offered a clean extract in these real samples. The proposed µ-SPE technique is proven to be sensitive, accurate and green with an analytical eco-scale score of 81, which supports green analysis for a better tomorrow