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Photodegradation of bensulfuron methyl, ( methyl-alfa-4,6-dimethoxypyrimidin-2-carbamoylsulfamoyl)-o-toluate ester) was carried out in aqueous solution under UV light. The rate of photolysis followed a first order kinetic. The main metabolites in distilled were tentatively idenified with a Diode Array Detector (DAD) and mass spectometry (MS) as (4,6-dimethoxy-2-pyrimidinyl)urea (1), methyl-alfa-4,6-dimethoxy-2-pyrimidinyl)amino-o-toluate 4) and alfa-sulfamoyl-o-toluic acid (2) that cyclises to 2-mthylsulfonylbenzoic acid imine (3). A mechanism which accounts for the formation of photoproducts is proposed

Photodegradation of imazosulfuron 1-(2-chloroimidazo [1,2-a] pyridin-3-yl-sulfonyl)-3-(4,6-dimethoxypyrimidin-2-yl) urea was carried in aqueous solution and in acetonitrile under UV-light. The rates of photolysis in both conditions followed first-order kinetics. The main metabolite in distilled was identified as (4,6-dimethoxypyrimidine-2-yl)aminocarbonylsulfamic acid (SDPM). A mechanism which accounts for the formation of the photoproducts is proposed.

In this paper an analytical method for the extraction and the determination by HPLC-UV of flavone (2-phenyl-4-H-1-benzopyran-4-one) in human serum has been developed. This analyte may have some effects on drug metabolism, interacting with microsomial hepatic enzymes. The proposed method is rapid and simple, with high recoveries (98%), good sensitivity (LOD 7,5 g/mL) and reproducibility (C.V. 8%) and could be utilized for routine epidemiological analysis. Preliminary pharmacokinetics studies showed that flavone hits the maximum blood level into two hours.

The paper present an analytical profile of Zolpidem. The applications of chromatographic methods (HPLC and HPTLC) and non-aqueous titrimetry in the analysis of this drug are described. Partition coefficients at pH 2.0 and 7.4 and absorptivity values have been determined. Reversed phase HPLC and HPTLC systems have been successfully performed utilizing methanol/water mixtures as eluent and octadecylsilane as stationary phase. Acidimetric and alkalimetric methods in non aqueous titrimetry have been applied for quantitative analysis. The suggested procedures are proposed as an effective tool for quality control on pure compound and pharmaceutical formulations.

The release kinetics of monolithic drug deliverydevices based on poly(ethylene oxide)(PEO) was investigated. Wter soluble PEO's with molecularweights of 600,000 and 4,000,000 and two blends were studied. the water swelling and dissolution characteristics of the two blends, along with the diffusivity of the drug etofylline in the water-penetrated polymer gels were analyzed. The higher molecular weight PEO and the two blends underwent swelling rather than polymer dissolution. As a result, a non constant release induced by the prevailing diffusive control was observed. Conversely,the drug release from the lower molecular weight PEO was aresult of equal rates of swelling and dissolutn, which gave a constant release rate.

The levels of bisphenol A (BPA), bisphenol B (BPB), bisphenol F (BPF) and bisphenol S (BPS) were monitored in twenty-three samples of canned legumes from popular brands marketed in Italy. BPB, BPS and BPF were not detected in any samples, while BPA was found in 91 % of the samples in the concentration range 1.51-21.22 ng/mL. The risk associated with the human exposure to BPA was categorized using the Rapid Assessment of Contaminant Exposure (RACE) tool promoted by the European Food Safety Authority (EFSA). The results showed that there is no risk for any of the population groups when the current TDI value for BPA of 4 μg/kg bw/day was used as toxicological reference point. In contrast, using the new TDI value for BPA of 0.04 ng/kg bw/day, proposed by EFSA in December 2021, the existing risk was found to be real for all population groups.

Phenolic compounds in olive oil are considered interesting, both for their effect on human wellness and for their role in the shelf life of olive oils. Many methods have been suggested for quantitative analysis of phenolic compounds in extra virgin olive oil, which determine that results are not always comparable; therefore, it is necessary to have simple, inexpensive, robust, and validated methods for official routine analyses. In this work, solid phase extraction (SPE) was carried out to isolate polyphenols from olive oil and the traditional colorimetric assay (Folin-Ciocalteu method) was used to quantify them. SPE/colorimetric method was validated for total polyphenols official determinations in extra virgin oils. The proposed method was robust, precise, and accurate. Polyphenol recovery was excellent ≥ 95% in 100–500 ppm measuring range.

Background: Bisphenols and alkylphenols are industrial chemicals widely used in the manufacture of plastics. In addition, alkylphenols are commonly used as intermediates to produce surfactant. In the last few years, concerns about the use of these substances have increased due to their negative effects as Endocrine Disruptors. Humans may be exposed to bisphenols and alkylphenols through several sources but foods are believed to be the main exposure route. Methods: An overview of the literature concerning the analysis of the bisphenol and alkylphenol levels in foods has been reviewed. We focused on the most recent literature (2010-2016) and only articles, reporting analyses on more than ten samples were considered. Results: Concentration levels of alkylphenols in foodstuffs, reported in the literature, suggest diet to be an important route of human exposure to these contaminants. BPA is still the most detected bisphenol in food matrices. It is ubiquitous in foodstuffs prevailing in canned foods that continue to be the main route of exposure to bisphenols for humans. However, its levels are always below the current migration limits. Conclusion: Data concerning the levels of multiple bisphenols in foods are still poor as well as toxicological studies on the potential effects of the bisphenol mixtures. Based on the foregoing, further studies should be carried out in order to collect scientific findings to help governments, policy makers, and food safety authorities to amend the current legislation on bisphenols.

Tomatoes are one of the most widely consumed vegetables in the Mediterranean Diet. They are a rich source of antioxidant compounds and their consumption is linked with a reduction of various types of pathologies. In addition to geographical and seasonal variables, cultivar is an important factor affecting the profile and the concentration of antioxidant compounds. “Pomodorino Vesuviano” is a Protected Designation of Origin (PDO) tomato cultivar traditionally grown in Campania (southern Italy), which to the best of our knowledge has never been analyzed for bioactive compounds before. Here we present a study conducted to investigate the carotenoid and flavonoid content in tomatoes from this cultivar. Results indicate that Pomodorino Vesuviano is a rich source of antioxidants, with lycopene (78.6 mg/kg fresh weight (fw)) and quercetin (8.52 mg/kg fw) are the major components. Moreover, cell-based studies have suggested that a synergistic effect among phytochemicals in tomatoes is responsible for their antioxidant activity, since the combination of low concentrations of carotenoids and polyphenols (i.e. per se inactive concentrations) resulted in a significant reduction of reactive oxygen species (ROS) formation. .

Lutein, a yellow dihydroxylated carotenoid, is present in many dietary supplements due to its biological properties. Currently, lutein is extracted from marigold flowers by expensive and time-consuming processes. Since tomatoes contain significant levels of lutein, in this study we have examined the feasibility of using tomato by-products as an alternative, low-cost source of this carotenoid. The determination of this carotenoid was performed by highperformance liquid chromatography???diode array detection, after selective extraction from tomato waste product samples. Lutein levels ranged from 9.9 to 10.5 ??g/g dry weight. Tomato waste products may be indicated as an alternative commercial source of lutein for food fortification and/or dietary supplements.

Bisphenol A (BPA) and bisphenol B (BPB) concentrations were determined in peeled canned tomatoes of different brands bought in Italian supermarkets. Tomato samples analyzed were packaged in cans coated with either epoxyphenolic lacquer or low BADGE enamel. A solid phase extraction (SPE) was performed on C-18 Strata E cartridge followed by a step on Florisil cartridge. Detection and quantitation were performed by a reversed phase high-performance liquid chromatography (RP-HPLC) method with both UV and fluorescence detection (FD). On the total of 42 tested tomato samples, BPA was detected in 22 samples (52.4%), while BPB was detected in 9 samples (21.4%). BPA and BPB were simultaneously present in 8 of the analyzed samples. The levels of BPA found in this study are much lower than the European Union migration limits of 3 mg/kg food and reasonably unable to produce a daily intake exceeding the limit of 0.05 mg/kg body weight, established by European Food Safety Authority.

Background Growing evidence suggests that the endocannabinoid system is involved in the pathogenesis of Alzheimer's disease (AD) and atherosclerosis. Objective The purpose of this study was to investigate the activation of the endocannabinoid system in AD in vivo and the possible intermediate role of atherosclerosis. Methods We enrolled 41 patients with probable AD, and 30 age- and gender-matched controls. All subjects underwent: ultrasound examination of cerebral and neck vessels (including intima-media thickness and plaque stenosis evaluation); blood sampling to measure levels of endocannabinoid [anandamide (AEA), 2-arachidonoylglycerol (2-AG)] and endogenous AEA analogues [N-palmitoyl-ethanolamide (PEA); N-oleoyl-ethanolamide]; neuropsychological evaluation and brain MRI (atrophy, white matter hyperintensity volume). Results 2-AG levels were higher in AD patients compared to controls (Mann-Whitney test p = 0.021). In the AD group, 2-AG correlated to white matter hyperintensity volume (r = 0.415, p = 0.015) and was higher in patients with chronic heart ischemic disease (p = 0.023). In AD patients, 2-AG was also positively related to memory (r = 0.334, p = 0.05) and attention (r = 0.423, p = 0.018) performances. Constructional praxia test scores were lower in patients with higher levels of PEA (r =-0.389, p = 0.019). Conclusion AD patients present high plasma 2-AG levels, also in relation to heart ischemic disease and cerebral leukoaraiosis. This may be a protective mechanism hindering neurodegeneration, but it may also play an ambivalent role on cerebrovascular circulation. The increase in 2-AG and PEA levels observed with ongoing pathological processes may differently modulate cognitive performances.

A multianalyte method has been developed for the confirmation and quantification of four neonicotinoids, acetamiprid, imidacloprid, thiacloprid and thiamethoxam in drinking water. These insecticides were extracted from water by solid-phase extraction (SPE) LiChrolut EN. Analytes’ determination and quantification were performed by liquid chromatography–mass spectrometry (LC–MS). Extraction efficiency experiments demonstrated the ability of this method to extract nicotinoids from water samples. Confirmatory analysis was carried out by LC-electrospray ionization–mass spectrometry (LC-ESI–MS) instrumentation equipped with a single-quadrupole mass filter. MS data acquisition was performed by two-ion selected ion monitoring (SIM) program. Average recoveries of the four analytes from drinking water samples were in the range of 95 and 104% with relative standard deviations (R.S.D.) < 20%. The limit of quantification (LOQ) for each of the four insecticides was 0.03 microgL−1.

Knowledge of the kinetics and pathways of hydrolytic degradation is crucial to the prediction of the fate and transport mechanism of chemicals. This work first describes the kinetics of the chemical hydrolysis of imazosulfuron, a new sulfonylurea herbicide, and evaluates the results to propose a degradation pathway. The hydrolysis of imazosulfuron has been studied in aqueous buffers both within the pH range 1.9-12.3 at ambient temperature (thermostated at 25 +/- 2 degrees C) and at pH 3.6 within the temperature range of 15-55 degrees C. The hydrolysis rate of imazosulfuron was characterized by a first-order kinetics, pH- and temperature-dependent, and accelerated by acidic conditions and higher temperatures. The calculated half-lives at pH 4.5 and 5.9 were 36.5 and 578 days, respectively. At pH 6.6, 7.4, 9.2, and 12.3 no significant change in imazosulfuron concentration was observed after 150 days. Half-lives were much lower at pH4 (= imazosulfuron pK(a)), at which they ranged from 3.3 to 6.3 days. Moreover, a change in temperature from 15 to 25 degrees C in acidic conditions (pH 3.6) decreased the half-life of imazosulfuron by a factor of approximately 4.0; in any case, a 3-5-fold increase in the rate of hydrolysis was found for each 10 degrees C increase in temperature. In acidic conditions the only hydrolysis products were the two molecules resulting from the cleavage of the sulfonylurea bridge.

Understanding and quantifying the adsorption and desorption of herbicides by soil is important for predicting their fate and transport in the environment. Here we report a study concerning the adsorption and desorption, by four different soils, of imazosulfuron, 1-(2-chloroimidazo[1,2-a]pyridin-3-ylsulfonyl)-3-(4, 6-dimethoxypyrimidin-2-yl)urea, a new sulfonylurea herbicide. Both phenomena are well-described by the Freundlich equation, which shows this herbicide to be little adsorbed by each of the four soils investigated. The Freundlich adsorption constants, K(f-ads), ranged from 1.46 to 3.02. Distribution coefficients between soil and water, Kd, measured on soils of different organic matter contents and pH values showed an important effect of these two parameters on imazosulfuron retention. The Freundlich desorption data indicated that a significant amount of the imazosulfuron sorbed is not easily desorbed. The desorption process showed an evident hysteresis phenomenon, which may contribute to the persistence of imazosulfuron in soil.

The study presents a fully validated simple high-performance liquid chromatography method with diode array detection (HPLCDAD), able to accurately determine the melamine, fraudulently added, in protein supplements, commonly used fromhealthy adults to enhance exercise or sport performance. The validation strategy was intentionally oriented towards routine use and the reliability of themethod rather than extreme performance. For this reason, validation by accuracy profile, including estimation of uncertainty, was chosen. This procedure, based on the concept of total error (bias + standard deviation), clearly showed that thismethodwas able to determine melamine over the range of 0.05–3.0mg Kg−1, selected by taking into account the maximum residue levels (MRLs) proposed by European legislation to distinguish between the unavoidable background presence of melamine and unacceptable adulteration.The accuracy profile procedure established that at least 95% of the future results obtained with the proposed method would be within the ±15% acceptance limits of the validated HPLC-DAD method over the whole defined concentration range. 1. Introduction Melamine (2,4,6-triamino-1,3,5-triazine) is commonly used as a rawmaterial or additive in themanufacture ofmelamineformaldehyde plastics or can coatings for food contact materials. It canbe foundat low levels as a contaminant in a variety of foods due to the leaching from food contact materials [1– 4]. For its nephrotoxicity [5–10] this chemical should not be intentionally added into foods or edible materials, in any circumstances. On the contrary, it is fraudulently added to food and/or feed ingredients to boost their total protein content and increase their market value. Such adulteration exploits a limitation of themost common nonspecific protein tests such as Kjeldahl method, which use total nitrogen as an indicator of protein content (melamine contains 66.6% of nitrogen by weight). In recent years the illegal addition of melamine to animal feedstuffs and infant milk formula caused illness and deaths of human infants and pet animals, who had taken the contaminated foods, primarily as a result of the accumulation of melamine-uric acid crystals in the urinary tract [8, 11– 15]. That is why various international health organizations have established regulations on melamine content over a wide variety of foods in order to safeguard public health [9, 16, 17]. In order to harmonize maximum residue levels (MRLs), set in many countries all over the world, European Food Safety Authority has proposed a legal maximumresidue level (MRL) of 1.0mg/Kg for infant foods and 2.5mg/Kg for other foods to distinguish between the unavoidable background presence of melamine (fromfood contact materials, pesticide use, etc.) and unacceptable adulteration [18]. Protein supplements are largely used by athletes and physically active individuals to enhance nitrogen retention, to increase muscle mass, to prevent protein catabolism during prolonged exercise, and to promote muscle glycogen resynthesis following exercise. Therefore it is likely that the adulteration of this kind of supplements with melamine increases their apparent protein content. In the

A novel, precise, specific, accurate and rapid reversed-phase high performance liquid chromatographic method, with diode array detection, was developed, optimized and validated to determine the drug purity of cocaine street samples seized in Italy and to characterize the adulterants. The method was performed using a C18 column, under isocratic conditions, with potassium phosphate buffer–acetonitrile as the mobile phase, at 232 nm. Linearity was studied from 0.01 to 0.50 mg mL−1, with a determination coefficient (r2) higher than 0.9999. The limit of detection (LOD) and limit of quantification (LOQ) were 0.004 mg mL−1 and 0.01 mg mL−1, respectively. Precision was evaluated as repeatability and intermediate precision with relative standard deviations not exceeding 5%. Validation of the HPLC method was carried out following ICH guidelines. Also, the estimation of the uncertainty measurements was included. The proposed HPLC-DAD method was thus shown to be convenient and highly suitable for the routine analysis of seized samples of drugs of abuse.

This study proposes a fast, simple and sensitive liquid chromatography diode array detector (LC/UV-DAD)-based method for the simultaneous determination of eight sulfonylurea herbicides (bensulfuron methyl, chlorsulfuron, metsulfuron methyl, primisulfuron methyl, rimsulfuron, thifensulfuron methyl, triasulfuron and tribenuron methyl) in bovine whole milk at concentrations lower than the default limit of 0.01 mg kg(-1) allowed by current legislation (Regulation EC/396/2005 and following Annexes). An effective one-step solid phase extraction (SPE) and clean up procedure was defined with use of Chem Elut cartridges, providing good recoveries for all the analytes tested and with no matrix effects affecting method accuracy. Separation of herbicides was obtained on a C(18) column by acetonitrile- water gradient elution. Method validation has been performed according to European Commission Decision 2002/657/EC criteria, in terms of linearity, recovery, precision, specificity, decision limit (CC(α)) and detection capability (CC(β)). Typical recoveries ranged between 78.4% and 99.7%, at the maximum residue limits (MRLs) levels established by Regulation EC/396/2005, with relative standard deviations (RSD) no larger than 10%.