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The application of antibiotics in animals for therapeutic and growth promotion purposes and to meet the need to increase meat production has been reported to cause the development of antibiotic resistance and other health risks due to the consumption of poultry products. Therefore, the need for rapid and accurate analytical methods for the determination of drug residues has become necessary. The Quick, Easy, Cheap, Effective Rugged and Safe (QuEChERS) technique involves liquidliquid extraction by partitioning with acetonitrile, followed by clean-up with a mixture of magnesium sulphate and a primary secondary amine. The extract obtained was then analyzed using high-performance liquid chromatography (HPLC). The figures of merit of the analytical methodology were determined using optimized parameters and the calibration curve was linear over the tested concentration range. The linearity ranged from 5 to 500 µg/kg for all the drug residues, and the correlation coefficients (r2 ) were greater than 0.99. The limit of detection (LOD) ranged within 1.45 – 5.02 µg/kg while the limit of quantification (LOQ) ranged within 4.68 – 6.72 µg/kg. The inter-day and intra-day precisions for beef samples had respective ranges of 1.94 – 19.03 % and 2.78 - 9.04%, and the average recoveries were from 79.48 to 107.48 %. The selectivity was determined by a blank matrix containing external standards and a sample spiked with target analyte and the results indicate a good selectivity with no interferences.

A headspace solid-phase microextraction (HS-SPME) method was developed as a preliminary investigation using univariate approach for the analysis of 14 multiclass pesticide residues in fruits and vegetable samples. The gas chromatography mass spectrometry parameters (desorption temperature and time, column flow rate, interface temperature) and solid phase microextraction parameters (fiber coating type, extraction temperature and time, pH, salt addition, stirring rate, dilution factor, organic solvent type and amount) were all investigated and optimized. The optimum values for the optimized parameters are as follows: Injection Temperature, 270 °C; Interface temperature, 300 °C; Column flow rate, 1.3 mL/min; Fiber coating, PDMS/DVB; Extraction time, 30 mins; Extraction temperature, 60 °C; Stirring rate, 300 rpm; Salt addition, 10% (v/w) NaCl; pH, 7; Desorption time, 7 min; Desorption temperature, 270°C; Organic solvent 3 % (methanol/acetone, 21:79%). The optimization of the mixture of organic solvents was optimized using design of experiment (DOE) with simplex lattice, designed using Minitab Statistical Software®. The developed method was then applied to the analysis of samples of apple, tomato, broccoli, lettuce, grape, cucumber, cabbage and pear. The investigated pesticides were found to be below the maximum residue levels, while some were not found. This shows that the fruit and vegetable samples are safe for consumption and do not pose any health risk for consumers. Keywords: Univariate design, Simple lattice design, design of experiment, GC-MS, HS-SPME

Mycotoxins are common food contaminants which cause poisoning and severe health risks to humans and animals. The present study applied chemometric approach in liquid chromatography-tandem mass spectrometry (LC-MS/MS) optimization for simultaneous determination of mycotoxins, i.e., aflatoxins B1, B2, G1, and G2, and ochratoxin A. The validated quick, easy, cheap, effective, rugged, and safe (QuEChERS)-LC-MS/MS method was used to study the occurrence of mycotoxins in 120 food matrices. The recovery ranges from 81.94% to 101.67% with relative standard deviation (RSD) lesser than 11%. Through the developed method, aflatoxins were detected in raisin, pistachio, peanut, wheat flour, spice, and chili samples with concentration ranges from 0.45 to 16.93 µg/kg. Trace concentration of ochratoxin A was found in wheat flour and peanut samples which ranged from 1.2 to 3.53 µg/kg. Some of the tested food samples contained mycotoxins of above the European legal maximum limit.

Fruits and vegetables constitute a major type of food consumed daily apart from whole grains. Unfortunately, the residual deposits of pesticides in these products are becoming a major health concern for human consumption. Consequently, the outcome of the long-term accumulation of pesticide residues has posed many health issues to both humans and animals in the environment. However, the residues have previously been determined using conventionally known techniques, which include liquid-liquid extraction, solid-phase extraction (SPE) and the recently used liquidphase microextraction techniques. Despite the positive technological effects of these methods, their limitations include; time-consuming, operational difficulty, use of toxic organic solvents, low selective property and expensive extraction setups, with shorter lifespan of instrumental performances. Thus, the potential and maximum use of these methods for pesticides residue determination has resulted in the urgent need for better techniques that will overcome the highlighted drawbacks. Alternatively, attention has been drawn recently towards the use of quick, easy, cheap, effective, rugged and safe technique (QuEChERS) coupled with dispersive solid-phase extraction (dSPE) to overcome the setback challenges experienced by the previous technologies. Conclusively, the reviewed QuEChERS-dSPE techniques and the recent cleanup modifications justifiably prove to be reliable for routine determination and monitoring the concentration levels of pesticide residues using advanced instruments such as high-performance liquid chromatography, liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry. [ABSTRACT FROM AUTHOR]

Hollow fiber liquid-phase microextraction (HF-LPME) techniques coupled to chromatographic systems have been widely used for extraction and determination of diverse compounds. HF-LPME was able to provide better results in precision, accuracy, selectivity and enrichment factor, in addition to reduction of matrix effect and carry over. It is applicable within a wide pH range and compatible with most analytical instruments which enable the utilization of HF-LPME in a wide variety of applications. This review focused on the modified HF-LPME techniques, efficiency, comparison to other LPME methods and applications. [ABSTRACT FROM AUTHOR]

Abstract: The headspace solid-phase microextraction was developed to examine the organophosphorus (diazinon, malathion, chloropyrifos, quinalphos, profenofos) and organochlorine (chlorothalonil, α-endosulfan and β-endosulfan) pesticide residues in vegetable (cucumber) and fruit (strawberry) samples. The effects of washing by different solutions were evaluated for the reduction of organophosphorus and organochlorine pesticide residues contents. Gas chromatography with electron capture detection was used to analysis the investigated pesticides. The results showed that washing by a non-toxic solution can decrease the concentration of pesticide residues in the fruit and vegetable samples. The data further indicated that acetic acid was the most effective solution in removing the residues of the investigated pesticides from the fruit and vegetable samples when compared to sodium carbonate, sodium chloride and tap water. The amount of pesticides removed by solution washing is related to their water solubility and vapour pressure properties. [Copyright &y& Elsevier]

Sample preparation has been identified as the most important step in analytical chemistry and has been tagged as the bottleneck of analytical methodology. The current trend is aimed at developing cost-effective, miniaturized, simplified, and environmentally friendly sample preparation techniques. The fundamentals and applications of multivariate statistical techniques for the optimization of microextraction sample preparation and chromatographic analysis of pesticide residues are described in this review. The use of Placket-Burman, Doehlert matrix, and Box-Behnken designs are discussed. As observed in this review, a number of analytical chemists have combined chemometrics and microextraction techniques, which has helped to streamline sample preparation and improve sample throughput. [ABSTRACT FROM AUTHOR]

The article presents a review of the application of various modes of solid-phase microextraction (SPME) for the analysis of pesticide residues in fruits and vegetables. Modes and types of SPME, including fiber types, optimization of extraction conditions, and the various analytical instruments used are included in the review. The characteristics of analytical procedures and trends in fiber production using sol-gel technology and molecularly imprinted polymers are tackled.

Ayurveda is a traditional medical system used widely in India and increasingly worldwide. Here, we report on a patient with Parkinson's disease (PD) who developed marked striatal hand with antiparkinsonian medication withdrawal during Ayurvedic medicine treatment for her PD. Although a direct role for the Ayurvedic medicines in inducing the hand deformity cannot be excluded, we propose that severe dopaminergic deficiency (due to prolonged withdrawal of antiparkinsonian medications in the context of long-standing PD) was probably the main culprit in our patient. [ABSTRACT FROM AUTHOR]