Urinary steroid profiling (USP) was studied using high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) methods in 108 patients with adrenocortical adenoma (ACA) and in 31 patients with adrenocortical carcinoma (ACC). Thirteen ACC and Cushing's syndrome (ACC-CS) patients had two types of USP as well as 18 ACC patients without hypercortisolism. These four types differed by androgen and glucocorticoid secretion of the adrenal cortex. Fifteen main ACC features were observed by GC-MS. Urinary excretion of dehydroepiandrosterone (DHEA) was increased in 67.7 % of ACC patients and tetrahydro-11-deoxycortisol (THS) in 74.2 %. By combination of the following parameters: THS >900 μg/24 h and/or DHEA >1500 μg/24 h with ratios of 3α,16,20-pregnentriol/3β,16,20-pregnentriol (3α,16,20dP3/3β,16,20dP3) less than 6.0 and 3α,17,20dP3/3β,17,20dP3 less than 9.0 and the detection of "non-classical" 5-en-pregnens, not found in ACA and healthy persons, 100 % sensitivity and specificity of ACC and ACA differential diagnosis were achieved. Features of 21-hydroxylase and 11β-hydroxylase deficiency were observed by GC-MS in 32.2 and 61.3 % of the ACC patients, respectively. Additional features for ACC-CS diagnostic were increased urinary excretion of 6β-hydroxycortisol, 18-hydroxycorticosterone, the sum (UFF + UFE) obtained by HPLC, tetrahydrocorticosterone, and the sum (THF + THE + allo-THF) obtained by GC-MS.

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a b s t r a c tThe simple and easy performed automated method for the IR determination of petroleum products (PP) in water using extraction-chromatographic cartridges has been developed. The method assumes two stages: on-site extraction of PP during a sampling by using extraction-chromatographic cartridges and subsequent determination of the extracted PP using sequential injection analysis (SIA) with IR detection. The appropriate experimental conditions for extraction of the dissolved in water PP and for automated SIA procedure were investigated. The calibration plot constructed using the developed procedure was linear in the range of 3-200 μg L À 1 . The limit of detection (LOD), calculated from a blank test based on 3s was 1 mg L À 1 . The sample volume was 1 L. The system throughput was found to be 12 h À 1 .

A novel automatic stepwise injection headspace single-drop micro-extraction system is proposed as a versatile approach for automated determination of volatile compounds. The system application is demonstrated for ammonia determination in concrete samples. An ammonia gas was produced from ammonium ions and extracted on-line into 5 μL 0.1M H3PO4 to eliminate the interference effect of concrete species on the ammonia stepwise injection spectrophotometric determination. The linear range was 0.1-1 mg kg(-1) with LOD 30 µg kg(-1). The sample throughput was 4 h(-1). This system has been successfully applied for the determination of ammonia in concretes.

Drilling fluid (DF) is one of the main sources of chemical and biological contamination of deep ice cores and lake water samples in the exploration of Subgalcial Antarctic Lake Environments (SALE). In this study, we investigated the contamination of an ice core that represented the first samples of refrozen lake water obtained 1 year after the unsealing of Lake Vostok in 2012. We show that these samples contain inclusions of the DF with a concentration of at least 16.7 mg l−1 (0.0019% or 19 ppmv). This makes it extremely difficult to obtain reliable data on the real chemical composition of the lake water. The focus of our study is the organic components of the DF, which built up in the secondary ice while the water was freezing in the borehole. Of all the possible organic compounds of the DF, only phenol congeners (up to 32.4 mg l−1) and dichlorofluoroethane HCFC-141b (14.4 mg l−1), a DF densifier, were found in the central channel, which is the last part of the core to freeze in the borehole. We conclude that the phenol compounds emerge due to physical processes, namely fractionation, during freezing, rather than any chemical reaction between the DF and the lake water.