N,N-Dimethylformamide (DMF) is a well-known chemical entity that is extensively used for pharmaceutical, biomedical and chemical applications. Previous research identified the need for the development of an effective dosage form for the systemic delivery of DMF due to its unique antiviral properties. For purposes of quality control and evaluation during pharmaceutical product development, development of an analytical method was required. A gas chromatographic (GC) method was developed with a flame-ionization detector (FID) on a carbowax packed glass column. 2-Methoxyethanol was used as internal standard. The analytical method proved to be capable of separating DMF and 2-methoxyethanol adequately within a relatively short runtime of 2.5 min. The analytical method described was primarily developed for use in dissolution studies of DMF containing delivery systems. Various physicochemical properties of candidate internal standard materials were correlated with the observed retention times of these compounds. The best correlation (r2 ¼ 0.8077) was obtained between the boiling point and the retention time of the compounds for the current application. The boiling point of an internal standard candidate material may therefore be useful in predicting the retention time of that compound under similar conditions.

In plants, change in lipid composition is a common response to various abiotic stresses. Lipid constituents of bryophytes are of particular interest as they differ from that of flowering plants. Unlike higher plants, mosses have high content of very long-chain polyunsaturated fatty acids. Such lipids are considered to be important for survival of nonvascular plants. Here, using abscisic acid (ABA )-induced changes in lipid composition in Physcomitrella patens as an example, a protocol for total lipid extraction and quantification by gas chromatography (GC) coupled with flame ionization detector (FID) is described.

The use of Multi-Walled Carbon Nanotubes (MWCNT) as solid sorbent in Matrix Solid-Phase Dispersion (MSPD) extraction and preconcentration method was presented to determine some commonly used organophosphorus insecticides/OPIs in honey samples using a Gas Chromatography Flame Ionization Detector (GC-FID). OPIs are poisonous compounds used to kill insects and rodents by affecting their nervous system. The limit of detections obtained after MSPD extraction were 7.0 ng/g for Malathion, Malaoxon and Fenitrothion and 33.3 ng/g for Isomalathion. The recovery of the insecticides from spiked honey, ranged from 83.6% to 103.3% with % RSD ranged from 9.8% to 12.3% (n=3). The correlation coefficient (R2) of the calibration data varied from 0.9945 to 0.9987. Standard addition method was utilized to examine matrix-induced effects on analyte peaks, and to demonstrate the efficiency of the method. The MSPD extraction was successfully applied for the analysis of four honey samples but no insecticide residues were detected.

The extraction procedures for the determination of polycyclic aromatic hydrocarbons (PAH) concentrations in sediment samples had been developed by using GC-FID and GC-MS. The optimized methods were soxhlet extraction, ultrasonic bath extraction and solid phase micro extraction (SPME). In order to search out the main factors affecting extraction efficiencies of the methods, factorial design was used. The best extraction method was chosen and optimum values for main factors were selected for the development of the extraction method for PAH determination in sediment samples. The accuracy of the method was verified by analyzing NIST SRM 1597 (complex mixture of polycyclic aromatic hydrocarbons from coal tar). The selectivitiy and sensitivity obtained were quite adequate for the determination of PAHs in sediment sample. The best extraction and analysis methods were then applied to determine 16 PAHs in sea sediments from &Ouml / l&uuml / deniz Lagoon, Mugla, Turkey and 19 PAHs in Ikizcetepeler Dam Lake, Balikesir, Turkey sediments to illustrate the capability of the selected extraction and analysis method to detect PAHs and to determine the status of the contamination.

Increasing global energy demand and environmental concerns have fueled the exploration of sustainable and efficient methods for renewable fuel production. The conversion of cellulosic waste to hydrocarbon fuels using hydrogenated metal oxides presents a novel and eco-friendly approach to sustainably address energy demand. In this study, hydrogenated metal oxides were used as catalysts in a relatively low-temperature and atmospheric-pressure environment to facilitate the conversion of cellulosic waste into hydrocarbon fuels. Hydrogenated metal oxides have been introduced as potential hydrogen transfer catalysts. The expected result is the selective conversion of cellulose to hexane at relatively low temperatures, which significantly reduces energy consumption compared to traditional high temperature conversion techniques. The use of XPell R resulted in 2,000 ppm hexane in dodecane. Although the use of hydrogenated metal oxides for cellulosic waste conversion is promising, ongoing research and optimization efforts are crucial to enhance the catalyst efficiency and increase the yield.

<p>Freudenberg Household Products AB in Norrköping are manufacturer of sponge cloths with the well-known brand names of Wettex^® and Vileda^®. The production is based on the viscose fiber process and involves a high chemical demand. Recent customer complaints involve a diffuse smell from the cloths that is like a “garage odor” and occurs after a few uses. The company’s theory is that the smell derives from a chemical used in the process called Exxal 9.</p><p>The aim was to screen the washing water from two sections and the cloth before and after wash for the presence of Exxal 9 and other prominent components. The washing water samples consisted of a salt solution from one section and a water condensate from another section. A method to qualitatively and quantitatively examine the production samples was developed. To evaluate the variation over a short period of time, twelve samples were taken during four weeks. The focus for the analysis lay on production line Wx4, but comparisons with two other production lines, Wx7 and SL1, were also made. The method of choice was gas chromatography in combination with two different detectors; mass spectrometer for identification and flame ionization detector for quantification.</p><p>Exxal 9 could be identified in both of the washing water sections but in very various concentrations. At the production line Wx4, the mean concentration in the mother lye was 61.96 µl/l whereas the mean concentration in the condensate was 0.24 µl/l. The comparison between the different production lines showed significant variations, where Wx4 had the highest concentration. In the cloths, Exxal 9 could only be found before it had been washed. The concentration in the cloths was not high enough for quantification. In both the washing waters and cloths, additional unknown peaks were found. Attempts to identify all the unknowns were made but only two compounds were included in the commercial library; 2-ethyl-1-hexanol and 2-(2-butoxyethoxy)-ethanol.</p>

This thesis is focused on aroma compounds which are presented in a wide variety of products including perfume, cologne, cosmetics, toiletries, laundry products and detergens. The widespread use and exposure to aroma compounds of aforementioned products could cause a range of the adverse reactions such as contact dermatitis, asthma, eczema and breathing problems. There are a lot of aroma compounds triggering negative allergic reactions but EU regulations limit 26 the most important fragrance allergens. The presence of these substances has to be declared on the product label if a limit of 0,01 % for rinse off and 0,001 % for leave-on products is exceeded. Of these 26 substances, a methodology was elaborated for determination of 12 allergens in a experimental part of this thesis. A method by solid-phase microextraction (SPME) and gas chromatography-flame ionization detection (GC-FID) was applied for fragrance allergens identification, extraction and measurement. The optimal extraction conditions of SPME-GC method were investigated including equilibrium time, extraction time and extraction temperature to increase extraction efficiency. Another important point is the method by SPME-GC-FID was validated and following performance parameters were determined: repeatability, linearity, limit of detection (LOD) limit of quantitation (LOQ). SPME-GC-FID was tested and applied to real samples.

Experiments to determine the fate and transport of the chemical warfare agent (CWA) simulants diisopropyl fluorophosphate (DIFP), O,S-diethyl methylphosphonothioate (OSDEMP), and 2-Chloroethyl ethyl sulfide (CEES) exposed to complex matrix systems are reported here. The aforementioned simulants were used in place of O-isopropyl methylphosphonofluoridate (GB), O-Ethyl S-(2-diisopropylaminoethyl) methylphosphonothiolate (VX), and Bis (2-chloroethyl) sulfide (HD), respectively. At ambient temperature, simulant pH (2.63 to 12.01) and reaction time (1 minute to 24 hours) were found to have significant influence on the recovery of simulants from charcoal, plastic, and TAP (butyl rubber gloves) in aqueous media. Buffer systems used included, phosphate, acetate, borate, and disodium tetraborate. Organic extractions were carried out using a 90:10 (v/v) dichloromethane / 2-propanol solution. All extracts were analyzed with a gas chromatograph equipped with flame ionization and flame photometric detectors (GC-FID-FPD). The FPD was used to determine the amount of simulant recovery.

Petroleum powered vehicles emit volatile organic compounds (VOCs) through combustion that contributes to the pollution of the environment. A technique in the 1970s was developed to decrease these emissions, especially for nitrogen oxides (NOx) and sulphuric oxides (SOx) which is called exhaust gas recirculation (EGR). The technique works by recirculating a portion of the combusted gas back into the engine, this limits the NOx and SOx emissions because of lower temperatures and less available oxygen. The problems that follow these effects is the formation and condensation of acids that corrode the material of the EGR system, which are created by many different reactions. It is of importance to understand how the compounds in the EGR system behaves through analysis of authentic and simulated condensates, which is why a quantitative method for these compounds are of interest. The aim of the project was to develop a simple quantitative analysis method for formic acid, acetic acid, and lactic acid in aqueous solution, which was done at Gränges Sweden AB. The technique used for detection and quantification was gas chromatography (GC) coupled to a flame ionization detector (FID) and a water compatible polyethylene glycol (PEG) column. Fractional factorial design (FFD) was used for determination of adequate operating parameters of the GC method and the sample preparation. Sample preparation only required filtration and pH adjustment prior to direct aqueous injection (DAI) to the chromatographic instrument. Detection of the analytes was very difficult because of non-compatibility with the FID, and quantification of asymmetric peak shapes made this problem worse, omitting lactic acid from further analysis. Limit of detection (LOD) and limit of quantification (LOQ) was 490 and 1640 ppm for formic acid and 120 and 400 ppm for acetic acid, with an injection volume of 0.3 μL and split ratio 10:1. Limits were too high for every EGR sample leaving no peaks detected for the sample preparation used. Further development should be done with complementary techniques and sample reprocessing in order to quantify the compounds.

Diploma thesis summarizes available information about chiral analysis of synthetic musk compounds in the aquatic environment. In the theoretical part of the thesis chirality and importance of chiral analysis by means of examples of different environmental pollutants is documented. Further consideration is aimed on musk compounds, their classification, characteristics and their fate in the environment, especially in the aquatic environment. After that methods for chiral analysis of synthetic musk compounds are reviewed. The aim of the experimental part of this diploma thesis was to carry out the determination of thirteen representatives of musk compounds (2-cyclohexylethanol, allylcyklohexylpropionate, Arocet, Aroflorone, Citronellol, Fresco Menthe, Galaxolide, hexyl cinnamic aldehyde, HSA, isoamylsalicylate, isobornylacetate, Lilial and Linalool), out of which some compounds are chiral and some are achiral. For the analysis samples of wastewater from the wastewater treatment plant Brno - Modřice were taken. Target compounds were isolated by solid phase microextraction (SPME) and were subsequently analyzed by gas chromatography with flame ionization and mass spectrometric detection. On the basis of data evaluation the removal efficiency forgiven musk compounds in the wastewater treatment plant was assessed.