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An effective modified pre-concentration technique, namely Cloud Point Extraction (CPE) coupled with QuEChERS (quick, easy, cheap, effective, rugged, and safe)), was developed to extract and clean up four neonicotinoid pesticide residues (nitenpyram, imidacloprid, thiamethoxam, and thiacloprid) from honey samples. Two cloud point processes were performed, whereby Triton™ X-114 was used to extract neonicotinoid residues into the surfactant-rich phase and the analytes were then transferred into an alkaline solution by ultrasonication prior to clean-up via QuEChERS method. Numerous variables affecting extraction performance were investigated, including surfactant type and concentration, salt type and content, back-extraction agent type and concentration, solvent type, QuEChERS salt quantity, and incubation temperature and time. Ultra-high-performance liquid chromatography-tandem mass spectrometry triple-quadrupole (UHPLC-MS/MS) (QQQ) was used for analysis. The limits of detection (LODs) and quantification limits (LOQs) were 0.13 to 0.18 μg kg−1 and 0.2 to 2.3 μg kg−1 respectively. The overall recoveries of all target compounds were between 85.3% to 104.5%, and excellent repeatability was achieved with relative standard deviations (RSD) ranging from 2.0% to 11.5%. The proposed extraction approach successfully detected trace amounts of neonicotinoids in honey samples obtained from local markets. [ABSTRACT FROM AUTHOR]

This study presents a newly developed selective and sensitive dual-template molecularly imprinted polymer nanoparticles (MIPs) for simultaneous removal and clean up of nitenpyram (NIT) and imidacloprid (IMI) pesticide residues from light and dark honey samples. Determination and quantification of both pesticides were performed using ultra-high-performance liquid chromatography-tandem mass spectrometry, UHPLC-MS/MS. The sorbent MIPs best recoveries were obtained with 60 mg of sorbent MIPs, adsorption time of 20 min, and sample pH of 7. Low method limit of detection (LOD) and limit of quantification (LOQ) were achieved, ranging from 0.03 to 0.09 µg L−1 and 0.06 to 0.12 µg L−1, respectively. Intra-day precision and inter-day precision (RSD) varied between 0.6% and 2.0% and 5.0% to 13.0%, respectively. The developed method was successfully applied to honey samples with obtained mean recoveries in the range of 95.2% to 108% and 94.3% to 105% for NIT and IMI. [ABSTRACT FROM AUTHOR]

Background: The use of cosmetic products is considered a necessity for beautification in our daily lives. Cosmetic products composed of natural oils or fats as a main ingredient for various beneficial properties. Fats and oils are composed of various type of fatty acids with different compositions. Hence, fatty acids profile can be an effective chemical fingerprint for authentication analysis of cosmetic products. Objective: This systematic review aims to enlighten the current detection tools developing for fatty acids profile authentication analyses of cosmetic ingredients based on the effectiveness, halal status, safety, advantages and disadvantages of the methods. Methodology: The data were extracted from the scientific literatures published between October 2015 and 2020 in the Web of Science, Scopus and Google Scholar databases, and analyzed with Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA). Findings: Based on the systemic literature reviews, essential oil, argan oil, mineral oil, vegetable oil, and jojoba oil were among the mostly studied ingredients in cosmetics. Furthermore, a combination of more than one analytical instrument was utilized to profile fatty acids while the determination of the origin of the fatty acids is under scrutiny. The portable mass spectrometer combined with a direct inlet membrane (DIM) probe seems to be the best tool in terms of time consumption, cost, requires no sample preparation with high efficiency. The current review showed that the best cosmetic base is when the oil is composed of high concentration of fatty acids such as linoleic, oleic, stearic acid, and palmitic acids with concentration range from 19.7 ‐ 46.30%, which offers various beneficial properties to cosmetic products. [ABSTRACT FROM AUTHOR]

Anthropogenic emission is on the increase in urban cities due to increased human activities. However, the pollution level of heavy metals in urban environments due to emission from various anthropogenic sources could attain toxic levels to humans and biota. The roadside dust collected from Petaling Jaya, Malaysia was analysed for Pb, Cr, Cu, Cd, As, Ni, and Fe by using ZEE nit 650 P Graphite furnace atomic absorption spectroscopy. The contamination levels of these metals were assessed in terms of the geoaccumulation index (Igeo), enrichment factor (EF), contamination factor (Cf), and integrated pollution index (IPI). The result of the principal component analysis (PCA) and hierarchical cluster analysis (HCA) revealed that the variations found in different concentrations of heavy metals were mainly due to industrial and traffic emissions. The computed results of Igeo and EF of heavy metals in urban dust suggested that there were pollutions of Cd, Cu, Pb, and As. Meanwhile, Igeo and EF of Ni, Cr, and Fe were very low and posed no serious pollution. The Cf and IPI assessments also indicated that Cd, Cu, and Pb were the major pollutants in Petaling Jaya urban dust. On the other hand, the potential ecological risks for single element (Er) confirmed the IPI results and the potential ecological risk index (RI) indicated that generally, the degree of pollution of heavy metals in roadside dust of PJ was considerable. These results could help in the development of suitable management strategies to minimise pollution by using various remediation methods in Petaling Jaya. [ABSTRACT FROM AUTHOR]

This article demonstrates the first application of a copper-based porous coordination polymer (BTCA-P-Cu-CP) as a carbon paste electrode (CPE) modifier for the detection of malathion. The electrochemical behavior of BTCA-P-Cu-CP/CPE was explored using cyclic voltammetry (CV) while chrono-amperometry methods were applied for the analytical evaluation of the sensor performance. Under optimized conditions, the developed sensor exhibited high reproducibility, stability, and wide dynamic range (0.6–24 nM) with the limits of detection and sensitivity equal to 0.17 nM and 5.7 µAnMcm−1, respectively, based on inhibition signal measurement. Furthermore, the presence of common coexisting interfering species showed a minor change in signals (<4.4%). The developed sensor has been applied in the determination of malathion in spiked vegetable extracts. It exhibited promising results in term of fast and sensitive determination of malathion in real samples at trace level with recoveries of 91.0 to 104.4%. (RSDs < 5%, n = 3). A comparison of the two studied techniques showed that the HPLC technique is unable to detect malathion when the concentration is lower than 1.8 µM while 0.006 µM is detected with appropriate RSDs 0.2–5.2% (n = 3) by amperometric method. Due to the high sensitivity and selectivity, this new electrochemical sensor will be useful for monitoring trace malathion in real samples. [ABSTRACT FROM AUTHOR]

A novel porous coordination polymer adsorbent (BTCA-P-Cu-CP) based on a piperazine(P) as a ligand and 1,2,4,5-benzenetetracarboxylic acid (BTCA) as a linker was synthesized and magnetized to form magnetic porous coordination polymer (BTCA-P-Cu-MCP). Fourier transform infrared (FTIR), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), field emission scanning electron microscope(FESEM), energy-dispersive X-ray spectroscopy(EDS), CHN, and Brunauer–Emmett–Teller(BET) analysis were used to characterize the synthesized adsorbent. BTCA-P-Cu-MCP was used for removal and preconcentration of Pb(II) ions from environmental water samples prior to flame atomic absorption spectrometry(FAAS) analysis. The maximum adsorption capacity of BTCA-P-Cu-MCP was 582 mg g−1. Adsorption isotherm, kinetic, and thermodynamic parameters were investigated for Pb(II) ions adsorption. Magnetic solid phase extraction (MSPE) method was used for preconcentration of Pb(II) ions and the parameters influencing the preconcentration process have been examined. The linearity range of proposed method was 0.1–100 μg L−1 with a preconcentration factor of 100. The limits of detection and limits of quantification for lead were 0.03 μg L−1 and 0.11 μg L−1, respectively. The intra-day (n = 7) and inter-day (n = 3) relative standard deviations (RSDs) were 1.54 and 3.43% respectively. The recoveries from 94.75 ± 4 to 100.93 ± 1.9% were obtained for rapid extraction of trace levels of Pb(II) ions in different water samples. The results showed that the BTCA-P-Cu-MCP was steady and effective adsorbent for the decontamination and preconcentration of lead ions from the aqueous environment. [ABSTRACT FROM AUTHOR]

We are reporting the distribution of 15 polycyclic aromatic hydrocarbons (PAHs) in roadside soils and road dusts of five industrial areas around Kuala Lumpur city, namely Chan Saw Lin, Kuchai, Segambut, Kepong-1, and Kepong-2 using GC-MS and assessing their toxicological risk. The total PAH concentrations of PAHs in roadside soils of the industrial areas ranged from 2804 ± 2645 μg/kg (Kepong-2) to 18384 ± 12324 μg/kg (Chan Saw Lin), while for the road dusts, it ranged from 3056 ± 1929 μg/kg (Kepong-2) to 13581 ± 5295 μg/kg (Segambut). High molecular weight PAHs dominated the distribution of PAHs in all sampling locations for roadside soils and in road dust except for road dust of the Segambut industrial areas. Result of isomeric pair ratios and PCA used for the identification of the PAHs sources, suggested that the contribution of petrogenic sources is greater than the pyrogenic sources in almost all studied locations. Total B[a]Peqfor roadside soils and road dusts of studied areas, recorded highest in Chan Saw Lin and lowest in Kepong-2. Cancer risks caused by a long-period exposure to the PAHs in roadside soils of studied areas are still considered very low. [ABSTRACT FROM PUBLISHER]

The sequential extraction procedure proposed by the European Standard, Measurements and Testing (SM&T) program, formerly the Community Bureau of Reference (BCR), was applied for partitioning of heavy metals (HMs) in river sediments collected along the course of Sungai Buloh and the Straits of Malacca in Selangor, Malaysia. Eight elements (V, Pb, Cd, Cr, Co, Ni, Cu and Zn) from seven stations (S1-S7) and at different depths were analyzed using the modified BCR Sequential Extraction Procedure (SEP) in combination with ICP-MS to obtain the metal distribution patterns in this region. The results showed that heavy metal contaminations at S2 and S3 was more severe than at other sampling sites, especially for Zn, Cu, Ni and Pb. Nevertheless, the element concentrations from top to bottom layers decreased predominantly. The samples from the Straits of Malacca (S4-S7) the highest contamination factors obtained were for Co, Zn and Pb while the lowest were found for V and Cr, similar to Sungai Buloh sediments. The sediments showed a low risk for V, Cr, Cu and Pb with RAC values of less than 10%, but medium risk for Co, Zn (except S3), Cd at S1 and S2 and Ni at S1, S3 and S5. Zn at S3 and Cd at S3-S7 showed high risk to our sediment samples. There is not any element of very high risk conditions in the selected samples., (Copyright © 2011 Elsevier B.V. All rights reserved.)