Search results for "analytical procedures"
showing 10 items of 26 documents
Analytical procedures for short chain chlorinated paraffins determination - How to make them greener?
2019
Abstract The aim of the following paper was to gather current scientific information about the analytical protocols dedicated to measuring the content level of short-chain chlorinated paraffins (SCCPs) in various types of environmental samples. Moreover, the data about the basic validation parameters of applied procedures for SCCPs determination are listed. The main issue which is highlighted in the paper is the possibility of the application of green analytical chemistry (GAC) principals in the SCCPs measuring process to reduce the environmental impact of the applied methodology. Analytical methods dedicated to SCCPs determination contain a significant number of steps and require advanced …
Photochemical sample treatment: a greener approach to chlorobenzene determination in sediments.
2014
Abstract Due to worker׳s exposure, solvent and stationary phases׳ consumption, sample purification is one of the most polluting steps in analytical procedures for determination of organic pollutants in real samples. The use of photochemical sample treatment represents a valid alternative methodology for extracts clean up allowing for a reduction of the used amount of organic solvents. In this paper we report the first application on the photolytic destruction of organic substances to eliminate some of the interferences in the analysis of Chlorobenzenes in sediment samples. The method׳s efficiency and robustness were compared with classic silica column purification process currently used in …
‘In situ’ preparation of nitrous acid solutions by photoreduction in a flow assembly for analysis of pharmaceuticals
2003
The solutions of nitrite ion, or nitrous acid, are frequently used as reagent in different analytical procedures and in pharmaceutical analysis. The low stability of the aqueous solutions of this reagent implies the tedious work of freshly prepared solutions every day and being kept in the refrigerator. In this paper, a photoreactor formed by a low pressure mercury lamp and nesting in a continuous-flow manifold is studied, tested, and proposed for the in situ reduction of nitrate solution into nitrite. The conversion into nitrite is reproducible and it has been successfully applied to determination of different drugs, mostly from the sulphonamide family, in an FIA assembly.
Use of QSAR methods for predicting the chemiluminescent behaviour of organic compounds upon reaction with potassium permanganate in an acid medium
2009
In previous work, molecular connectivity computations were successfully used to predict the chemiluminescent behaviour of organic compounds upon reaction with common strong oxidants and the native fluorescence too; both of them in a liquid phase. The obtained results were used to develop new analytical procedures to the given compounds. For the first time, connectivity methods were used for a purely analytical purpose. In this work, we went deeper into the knowledge of direct chemiluminescence processes by using molecular connectivity in the form of QSAR methods to predict the chemiluminescence intensity produced by reactions between organic compounds (pharmaceuticals mainly) and potassium …
Biochips for cell biology by combined dip-pen nanolithography and DNA-directed protein immobilization.
2013
A general methodology for patterning of multiple protein ligands with lateral dimensions below those of single cells is described. It employs dip pen nanolithography (DPN) patterning of DNA oligonucleotides which are then used as capture strands for DNA-directed immobilization (DDI) of oligonucleotide-tagged proteins. This study reports the development and optimization of PEG-based liquid ink, used as carrier for the immobilization of alkylamino-labeled DNA oligomers on chemically activated glass surfaces. The resulting DNA arrays have typical spot sizes of 4-5 μm with a pitch of 12 μm micrometer. It is demonstrated that the arrays can be further functionalized with covalent DNA-streptavidi…
Determination of the mineral composition of foods by infrared spectroscopy: a review of a green alternative.
2014
The determination of mineral composition of foods involves, in most cases, the use of long and tedious sample preparation, which consumes acids and reagents and sometimes requires the use of expensive instrumentation. This is the main reason for the search for direct analytical procedures, based on the use of infrared sample spectra and chemometrics, to model the signals in order to determine the presence of essential and trace toxic elements in foods. The state-of-the-art of the research in this field has been established in the present review article from the critical evaluation of articles available in the literature. Chemometric methods employed and their validation, together with a dis…
Approach of the State Pharmacopeia of Ukraine to analytical procedures validation on the example of chloride ions assay in peritoneal dialysis soluti…
2019
The objective of this study was to develop and validate an alternative analytical procedure for the total chloride assay in solutions for peritoneal dialysis (PD). The proposed analytical procedure was validated according to the requirements of the International Conference on Harmonization (ICH) Guideline: Topic ICH Q2(R1) and the approach of the State Pharmacopeia of Ukraine (SPU). The analytical procedure was specific. The li-nearity of the procedure was evaluated in the concentration range of 76 to 114 mmol/L of chloride ions (80-120% of the stated content (95 mmol/L)) with the regression equation y = 1.0029 ∑ X -0.2269 and a correlation coefficient of 0.9989. The y-intercept of the regr…
Standardisation of elemental analytical techniques applied to provenance studies of archaeological ceramics: an inter laboratory calibration studyEle…
2002
Chemical analysis is a well-established procedure for the provenancing of archaeological ceramics. Various analytical techniques are routinely used and large amounts of data have been accumulated so far in data banks. However, in order to exchange results obtained by different laboratories, the respective analytical procedures need to be tested in terms of their inter-comparability. In this study, the schemes of analysis used in four laboratories that are involved in archaeological pottery studies on a routine basis were compared. The techniques investigated were neutron activation analysis (NAA), X-ray fluorescence analysis (XRF), inductively coupled plasma optical emission spectrometry (I…
Background element content in the lichen Pseudevernia furfuracea: a comparative analysis of digestion methods
2019
In bioaccumulation studies, the interpretation of pollutant contents in the target biomonitor has to be performed by assessing a deviation from an unaltered reference condition. A common strategy consists in the comparison with background element content (BEC) values, often built up by uncritically merging methodologically heterogeneous data. In this respect, the acid digestion of samples was identified as a major step affecting BEC data. Here, the analytical outcomes of two acid mixtures were compared on a set of matched paired samples of the lichen Pseudevernia furfuracea, a widely used biomonitor for which BEC values based on partial digestion were previously provided. The standard refer…
Comparison of quantitative analysis techniques for the determination of heat seal lacquer layers on aluminum blister foils
2010
For decades a gravimetric method has been common standard for the determination of heat seal lacquers on aluminum blister foils. With the availability of appropriate techniques such as interferometric, infrared reflection absorption spectroscopic (IRRAS), beta backscatter, impedance spectroscopic and eddy current techniques respectively, more efficient determinations can be foreseen which are subject of the present communication. The different methods were compared to each other regarding parameters required for validation of analytical procedures according to the ICH guidelines Q2 (R1) such as linearity, precision, accuracy, robustness and quantitation limits. The interferometric, IRRAS an…