Removal of imipramine using advanced oxidation processes: Degradation products and toxicity evolution.

Pharmaceuticals are frequently detected in natural and wastewater bodies, and are very important in environmental toxicology because of their stable nature. Advanced oxidation methods used to remove contaminants are of great benefit, especially removing pharmaceuticals unsuitable for biodegradation. In this study, imipramine was degraded by anodic oxidation and subcritical water oxidation, which are advanced oxidation methods. The determination of degradation products was performed by Q-TOF LC/MS analysis. The genotoxicity and cytotoxicity of the degradation samples were determined by the in vivo Allium Cepa method. Among the anodic oxidation samples, the lowest cytotoxicity was obtained after using 400 mA current, and 420 min of degradation time. No cytotoxic effect was observed in any subcritical water oxidation sample. However, when 10 mM hydrogen peroxide as an oxidant was used at 150 °C and the reaction time was 90 min, the subcritical water oxidation sample showed a genotoxic effect. The results of the study showed that it is crucial to evaluate the toxicity levels of the degradation products and which advanced oxidation methods are preferred for removing imipramine. The optimum conditions determined for both oxidation methods can be used as a preliminary step for biological oxidation methods in the degradation of imipramine.

A Rapid, Precise, and Sensitive LC-MS/MS Method for the Quantitative Determination of Urinary Dopamine Levels via a Simple Liquid-liquid Extraction Technique.

OBJECTIVES: Dopamine (DA) is a prominent biochemically complex neurotransmitter and immunomodulator. The quantification of DA could contribute to a better understanding of how endocrine system, cardiovascular and renal functions are regulated. The study aims to develop a rapid, precise, and extremely sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for routine clinical quantification of DA in urine. MATERIALS AND METHODS: Urine samples were extracted via one simple and rapid liquid-liquid extraction technique; then analyzed using a sensitive LC-MS/MS method developed by multiple reaction monitoring mode. RESULTS: DA and internal standard (IS) retention durations were found to be 2.28 min and 2.24 min, respectively. The mean extraction recovery of DA and DA-IS in urine was above 95.62%. DA calibration curve in urine was linear (r2≥0.998) ranging from 20 ng/mL to 1000 ng/mL. The maximum intra-day and inter-day precisions were 5.87 and 2.81, respectively and coefficients of variation were 10.55% and 7.57%, respectively. CONCLUSION: A rapid, precise, sensitive and quantitative LC-MS/MS detection of DA without the use of derivatization, evaporation, reconstitution and ion-pairing reagents has been developed with a simple and non-invasive sample technique for clinical laboratory applications, basic neuroscience research and drug development studies.

Monitoring of Lawsone, p-phenylenediamine and heavy metals in commercial temporary black henna tattoos sold in Turkey.

BACKGROUND: Henna has a very low allergic potential, and severe allergenic contact dermatitis is mainly caused by p-phenylenediamine (PPD), which is added to temporary black 'henna tattoos', and potentially also by some heavy metals. OBJECTIVE: To determine the presence of, and quantify, Lawsone, PPD and heavy metal contaminants (cobalt, nickel, lead, and chromium) in commercial temporary black henna tattoo mixtures (n = 25) sold in Turkey. METHODS: Lawsone and PPD concentrations were analysed with high-performance liquid chromatography, and heavy metal quantification was performed with inductively coupled plasma mass spectrometry. RESULTS: PPD was found in all 25 black henna tattoo samples purchased from tattoo shops; levels varied between 3.37% and 51.6%. Lawsone was detected (0.002-88.2%) in 21 of the 25 temporary black henna tattoo samples analysed. Heavy metal contaminant levels were 0.44-3.11 ppm for Co, 1.13-2.20 ppm for Ni, 1.59-17.7 ppm for Pb, and 35.0-76.9 ppm for Cr. CONCLUSIONS: Our results suggest that commercial temporary black henna mixtures containing PPD levels up to 51.6% pose a risk of contact sensitization and severe allergic contact dermatitis among users. It is important to identify both the additives and metallic contaminants of black henna tattoo products; the significance of metal contaminants has still to be assessed.