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The evaluation is described of an automated pyrolysis-gas chromatography-mass spectrometry system combined with a software package to convert total ion current chromatograms into forms that resemble a conventional mass spectra called "spectragrams". The spectragram for a single paint sample can be "closest fit" matched to a previously created paint pyrogram library via pre-determined target compounds in a handling list. Up to 45 paint samples can be dealt with in an overnight unattended run.

Determination by gas chromatography-mass spectrometry, after extraction into hexane, of the relative amounts of the three most abundant cannabinoids, cannabidiol (CBD), Δ9-tetrahydrocannabinol (Δ9-THC) and cannabinol (CBN), and the six next most abundant compounds in cannabis resin all showed significant variations in their relative amounts with sampling position. Thus, data from a single sub-sample cannot be regarded as characteristic of a cannabis resin bar or without further evidence of coming from a particular resin bar or batch of bars. A cannabis resin bar stored under ambient conditions for 12 months showed major loss of Δ9-THC and an increase in CBN content as well as variations in composition with sampling position.

It has been shown that by using pyrolysis–gas chromatography–mass spectrometry (Py–GC–MS), it is possible to discriminate between a variety of automotive clear coat paints, indistinguishable by Fourier transform infrared spectroscopy (FT-IR).

It has been shown that by using pyrolysis–gas chromatography–mass spectrometry (Py-GC-MS), it is possible to discriminate between a variety of base coat, solid paint and clear coat samples of automotive paints in commercial use from a wide range of car manufacturers. Some of the solid paints and clear coats were pairs of samples indistinguishable by fourier transform infrared spectroscopy (FT-IR).

Here we report the results of the largest study yet carried out on composition profiling of seized "ecstasy" tablets by Raman spectroscopy. Approximately 1500 tablets from different seizures in N. Ireland were analysed and even though practically all the tablets contained MDMA as active constituent, there were very significant differences in their Raman spectra, which were due to variations in both the nature and concentration of the excipients used and/or the degree of hydration of the MDMA. The ratios of the peak heights of the prominent drug bands at 810 cm(-1) and 716 cm(-1) (which vary with hydration state of the drug), and the drug band at 810 cm(-1) against the largest clearly discernible excipient band in the spectrum were measured for all the samples. It was found that there was sufficient variation in composition in the general sample population to make any matches between batches of tablets taken from different seizures significant, rather than the result of random chance. Despite the large number of different batches of tablets examined in this study, only two examples of indistinguishable sets of tablets were found and in only one of these had the two batches of tablets been seized at different times. Finally, the fact that there are many examples of batches of tablets (particularly in different batches taken from single seizures) in which the differences between each set are sufficiently small that they appear to arise only from random variations within a standard manufacturing method implies that, with more extensive data, it may be possible to recognize the "signature" of tablets prepared by major manufacturers.

Aluminium was determined by flow injection spectrofluorimetry at 510 nm after excitation at 396 nm following extraction of tetraphenylphosphonium aluminium(III) 8-hydroxyquinoline-5-sulphoxinate into chloroform. The effects of diverse ions and masking studies are reported. The system has been applied to the determination of aluminium in steels by the method of standard additions.

Tantalum (0–20 μg) can be determined spectrophotometrically at 482 nm after extraction as tetrabutylammonium hexathiocyanatotantalate(V) into ethyl acetate. The effects of diverse ions, reagent conditions and masking agents are reported. The system has been applied to the determination of tantalum in tin slag samples.

Bismuth (0–20 μg ml −1 ) can be determined spectrophotometrically at 485 nm after its adsorptive extraction from dilute sulfuric acid solution as tetrabutylammonium tetraiodobismuthate(III) on microcrystalline benzophenone followed by dissolution of the solid phase in ethyl acetate. The effects of reaction conditions, diverse ions and masking studies are reported. The system has been applied to the determination of bismuth in pharmaceutical samples.

Nickel was determined by flow injection spectrophotometry at 370 nm after extraction of nickel(II) bis(acetylacetone)ethylenediiminate chelate into chloroform. The carrier stream was deionized water and the reagent streams were phosphate buffer (pH 7.0) and 1.5% (w/v) bis(acetylacetone)ethylenediimine solutions. The reaction stream was heated to 60°C and then cooled to room temperature prior to extraction into chloroform. The sampling rate was 18 h−1. The calibration graph was linear up to 25 μg ml−1 nickel, based on injection volumes of 250 μl. The relative standard deviation (n=10) was 0.98% for 20 μg ml−1 nickel. The system has been applied to the determination of nickel in nickel–copper alloys and in synthetic electroplating solutions.

Raman spectroscopy with far-red excitation has been investigated as a simple and rapid technique for composition profiling of seized ecstasy (MDMA, N-methyl-3,4-methylenedioxyamphetamine) tablets. The spectra obtained are rich in vibrational bands and allow the active drug and excipient used to bulk the tablets to be identified. Relative band heights can be used to determine drug/excipient ratios and the degree of hydration of the drug while the fact that 50 tablets per hour can be analysed allows large numbers of spectra to be recorded. The ability of Raman spectroscopy to distinguish between ecstasy tablets on the basis of their chemical composition is illustrated here by a sample set of 400 tablets taken from a large seizure of >50000 tablets that were found in eight large bags. The tablets are all similar in appearance and carry the same logo. Conventional analysis by GC-MS showed they contained MDMA. Initial Raman studies of samples from each of the eight bags showed that despite some tablet-to-tablet variation within each bag the contents could be classified on the basis of the excipients used. The tablets in five of the bags were sorbitol-based, two were cellulose-based and one bag contained tablets with a glucose excipient. More extensive analysis of 50 tablets from each of a representative series of sample bags gave distribution profiles that showed the contents of each bag were approximately normally distributed about a mean value, rather than being mixtures of several discrete types. Two of the sorbitol-containing sample sets were indistinguishable while a third was similar but not identical to these, in that it contained the same excipient and MDMA with the same degree of hydration but had a slightly different MDMA/sorbitol ratio. The cellulose-based samples were badly manufactured and showed considerable tablet-to-tablet variation in their drug/excipient ratio while the glucose-based tablets had a tight distribution in their drug/excipient ratios. The degree of hydration in the MDMA feedstocks used to manufacture the cellulose-, glucose- and sorbitol-based tablets were all different from each other. This study, because it centres on a single seizure of physically similar tablets with the same active drug, highlights the fact that simple physical descriptions coupled with active drug content do not in themselves fully characterize the nature of the seized materials. There is considerable variation in the composition of the tablets within this single seizure and the fact that this variation can be detected from Raman spectra demonstrates that the potential benefits of obtaining highly detailed spectra can indeed translate into information that is not readily available from other methods but would be useful for tracing of drug distribution networks.

Niobium was determined by flow injection spectrophotometry at 393 nm after extraction of ethylene-bis(triphenylphosphonium)thiocyanatoniobate(V) into chloroform. The effects of diverse ions are reported. The system has been applied to the determination of niobium in steels by the method of standard additions.

This review outlines aspects of the various phases of Swiss chemistry from the introduction of alchemy in Western Europe, its transition to chemistry as a science and profession and the more recent practice. Attention is drawn to the large number of Swiss Nobel Laureates in chemistry and the contributions of Swiss physicists to chemical spectroscopy, from the days of Balmer. In all periods, Swiss chemistry has had European dimensions, and links can be traced to most host countries of previous Euroanalysis conferences and indeed to the next, at Lisbon, in AD 2000.

Described herein are analytical procedures for the characterisation of slurry explosives by way of the qualitative and quantitative identification of the major constituents (Al, Na+, Ca2+, NH+4, CH3NH+3, NO−3, laurylamine acetate). Three explosive samples of similar composition were discriminated using this systematic approach.

It is shown for the first time that a Fourier-transform infra-red spectroscopic study of cyanoacrylate fumed fingerprints provides a non-subjective confirmation of visual estimates of polymer deposition as made by fingerprint experts. The greatest degree of polymer deposition on latent prints within the parameters of the experiment were produced by prior exposure to ammonia followed by fuming with methyl cyanoacrylate monomer. The method with base activation also permits further quality enhancement of prints previously developed by the current method.

Chromium(VI) (0–120 μg) can be determined spectrophotometrically at 362 nm after its extraction as dihydrogen dichromate into propylene carbonate. The effects of acidity and diverse ions are reported. The relative standard deviation for the determination of 60 μg Cr(VI) was 0.81% ( n = 9). The system has been applied to the determination of chromium in steel (0.2–4% w/w Cr).

Cobalt (0–120 μg) can be determined spectrophotometrically at 625 nm after its extraction as benzyltributylammonium tetrathiocyanatocobaltate(II) into chloroform at pH 7. The effects of pH, diverse ions and masking studies are reported. The method has been applied to the determination of cobalt (0.2–10.0%, w/w) in high speed tool steels without prior separation of iron, and in vitamin B12.

A simple procedure has been demonstrated for the identification of laurylamine acetate in slurry explosives by electrospray/ mass spectrometry.

A procedure for the determination of three commonly encountered ecstasy type drugs has been demonstrated using proton nuclear magnetic resonance spectrometry ( 1 H-NMR).

Bismuth (0–160 μg) can be determined spectrophotometrically at 486 nm after its extraction as hydrogen tetraiodobismuthate (III) into propylene carbonate. The effects of reagent conditions, ionic strength and diverse ions are reported. The system has been applied to the determination of bismuth in pharmaceutical samples.

Copper was determined by flow injection spectrophotometry at 370 nm after extraction of copper(II) bis(acetylacetone)ethylenediiminate chelate into chloroform. The carrier stream was deionized water and the reagent streams were acetate buffer (pH 5.0) and 0.2% (w/v) bis(acetylacetone)ethylenediimine solutions. The sampling rate was 20 h −1 . The calibration graph was linear up to 100 μg ml −1 copper, based on injection volumes of 250 μl. The relative standard deviation ( n = 10) was 1.95% for 20 μg ml −1 copper. The system has been applied to the determination of copper in copper-based alloys and pig feeds.

Copper can be determined spectrophotometrically at 343, 370 and 545 nm, based on the reaction of copper(II) and bis(acetylacetone)ethylenediimine after extraction of the chelate into chloroform. The calibration graphs were linear up to 20 μg ml−1 copper at 343 nm, 80 μg ml−1 copper at 370 nm and 200 μg ml−1 copper at 545 nm. The relative standard deviation for the determination of 50 μg ml−1 of copper (at 545 nm) was 1.4% (n = 10). The system has been applied to the determination of copper in copper-based alloys and pig feeds.

Improved systems are reported for the determination of bismuth (0-0.1%, w/w) in copper-based alloys by flame atomic absorption spectrometry. The use of a slotted quartz tube atom trap (STAT) with nebulised solutions or coupled with hydride generation decreases the characteristic concentrations (nebulized solution, 0.44/0.25, without/with STAT; hydride, 0.022/0.014, without/with STAT) and improved precisions by factors of two compared with those obtained without the use of the STAT. Determination of bismuth in a series of reference materials demonstrates the usefulness of STAT systems for the analysis of metallurgical samples.

It has been shown that by use of gas chromatography with flame ionisation detection it is possible to identify patterns within the nitroaromatic isomer content of nitroglycerine-based explosives and hence to associate explosives from similar batch types.

It has been shown that the use of gas chromatography-mass spectrometry makes it possible to attribute a degree of characterisation to commercial nitroglycerine-based explosives by identifying and subsequently quantifying the nitroaromatic compounds inherent in the explosive types examined.

Copper can be determined spectrophotometrically at 600 nm based on the reaction of copper(II) and bis(cyclohexanone)oxalyldihydrazone using flow-injection analysis. The carrier stream was distilled water and the reagent streams were 27% ( frsol | w / v ) citric acid solution, 37% ( frsol | v / v ) ammonia solution and 0.18% ( frsol | w / v ) bis(cyclohexanone)oxalyldihydrazone solution. The calibration graph was linear up to 20 μg ml −1 copper and the relative standard deviation for the determination of 5 μg ml −1 of copper was 0.92% ( n = 10), the detection limit was 0.13 μg ml −1 copper, both based on injection volumes of 250 μl. The system has been applied to the determination of copper in steels, copper-based alloys and pig feeds and to monitoring copper in an alkaline scale removal process.

It has been shown that by using 500 MHz 1 H NMR it is possible, without prior separation, to quantify individual nitroaromatic compounds present in commercial nitroglycerine based explosives (gelignites). Patterns within the quantitative data provide a good degree of sample batch characterisation; typing of the explosive is achieved via total nitroaromatic content.

Sulphate can be determined spectrofluorimetrically (λem = 505 nm, λex = 410 nm) based on the formation of a ternary complex between sulphate, zirconium and calcein in a flow-injection system. The carrier stream was deionised water and the reagent streams were 100 μg ml−1 Zr (as ZrOCl2) in 1% (v/v) hydrochloric acid, and 40 μg ml−1 calcein in 0.1 M potassium hydroxide. The injection rate was 50 h−1. The calibration graph was linear up to 25 μg ml−1 SO2−4 based on 250-μl injection volumes. The relative standard deviation (n = 10) was 1.95% for 10 μg ml−1 SO2−4; the detection limit was 0.82 μg ml−1 SO2−4. The system has been applied to the determination of sulphur in NIST coal samples after oxygen bomb combustion.

Antimony (⩽ 20 μg) can be determined spectrophotometrically at 640 nm after its adsorptive extraction as Brillant Green hexachloroantimonate(V) with microcrystalline 1,4-dichlorobenzene after dissolution of the solid phase in toluene. The effects of reagent concentration, order and timing of addition, diverse ions and masking studies are reported. The system has been applied to the determination of antimony in steels.

Boron can be determined spectrofluorimetrically based on the reaction of borate ion and Alizarin Red S in aqueous media using flow-injection analysis. The carrier stream was deionized water and the reagent streams were 1% (w/v) EDTA, phosphate buffer (pH 7.5) and 2 × 10 −13 M Alizarin Red S solutions. The injection rate was 50 h −1 . The calibration graph was linear up to 40 μ ml −1 boron and the relative standard deviation for the determination of 4.0 μg ml −1 of boron was 0.83% ( n = 10). The detection limit was 0.34 μg ml −1 based on injection volumes of 250 μl. The system was applied to the determination of boron in electroplating solutions.

Molybdenum (0–2.5 μg) may be determined spectrophotometrically at 385 nm after flow-injection extraction into chloroform of the chelate of molybdenum(VI) with quinolin-8-ol. The carrier stream was dilute sulphuric acid, pH 0.85. The injection rate was 20 h−1. The calibration graph is linear up to 10 μg ml−1 Mo and the detection limit is 0.11 μg ml−1 based on injection volumes of 250 μl. The system has been applied to the determination of molybdenum in low alloy and mild steels.

Chromium(VI) can be determined spectrophotometrically at 365 nm after flow-injection extraction into chloroform of the ion associate benzyltributylammonium dichromate. The carrier stream was distilled water, merged with 1.0 M sulphuric acid solution, the reagent stream was 0.5% (w/v) benzyltributylammonium chloride solution. The injection rate was 20 h −1 . The calibration graph was linear up to 20 μg ml −1 and the detection limit (3 × baseline noise) was 0.5 μg ml −1 Cr(VI) based on 250-μl injection volumes. The system has been applied to the determination of chromium in steels.

Calcium can be determined spectrofluorimetrically (λ em = 520 nm, λ ex = 365 nm) based on its reaction with Calcein is strongly alkaline solution in a flow-injection system. The carrier stream was deionised water and the reagent streams were 0.6 M potassium hydroxide and 60 μg ml −1 Calcein. The injection rate was 50 h −1 . The calibration graph was sigmoid, but, however, linear between 3.0 and 7.0 μg ml −1 Ca based on injection volumes of 250 μl. The relative standard deviation ( n = 10) was 0.23% for 4 μg ml −1 Ca. The system has been applied to the determination of calcium is certified reference mineral samples.

Salbutamol can be determined spectrophotometrically at 605 nm after flow-injection extraction into chloroform after oxidative coupling with 4-amino- N,N -dimethylaniline. The carrier stream is distilled water and the reagents streams contain 5% (w/v) sodium hydrogencarbonate, 0.5% potassium hexacyanoferrate(III) and 0.1% (w/v) 4-amino- N,N -dimethylanilinium sulphate. The sampling rate is 20 h −1 . The calibration graph is linear up to 20.0 μg ml −1 salbutamol, based on injection volume 100 μl. The relative standard deviation ( n =10) was 1.9% for 10 μg ml −1 salbutamol. The system has been applied to the determination of salbutamol in pharmaceutical formulations.

Manganese(VII) (0–100 μg) can be determined spectrophotometrically at 548 nm after its extraction as benzyltributlammonium permanganate, at pH 6, into chloroform. The effects of pH, reagent concentrations and diverse ions are reported. The system has been applied to the determination of manganese in a variety of steels. For the determination of 60 μg of manganese the relative standard deviation was 0.19% (7 measurements).

Phosphate can be determined spectrophotometrically at 560 nm based on the reaction of 12-molybdophosphate and Crystal Violet using flow-injection analysis. The carrier stream was 0.5% (w/v) poly(vinyl alcohol) solution and the reagent streams were 0.1 M sodium molybdate, 5 x 10 −4 M Crystal Violet and 12.5% (v/v) nitric acid. The injection rate was 60 h −1 . The calibration graph was linear up to 5.0 μg ml −1 phosphate and the relative standard deviation for the determination of 1.0 μg ml −1 of phosphate was 0.69% ( n = 10). The detection limit was 0.02 μg ml −1 phosphate, based on an injection volume of 250 μl. The system was applied to the determination of phosphate in fertilizer and waste water samples.

Ascorbic acid may be determined spectrophotometrically at 360 nm based on reduction of vanadotungstophosphoric acid using flow-injection analysis. The carrier stream was distilled water and the reagent streams were buffer solution (pH 3.0), 1.735 × 10−3 M dodecatungstophosphoric acid and 1.735 × 10−3 M sodium vanadate. The injection rate was 80 h−1. The calibration graph was linear up to 80 μg ml−1 ascorbic acid and the relative standard deviation for the determination of 20 μg ml−1 ascorbic acid was 1.5% (n=10). The detection limit was 1.0 μg ml−1 ascorbic acid, based on an injection volume of 250 μl. The system was applied to the determination of ascorbic acid in vitamin C tablets.

The chemical nature and availability of soluble organic phosphorus for algal growth is largely unknown. A commercially available reverse osmosis water purification system was adapted for concentrating the soluble organic phosphorus fraction form 100-l volumes of drainage water collected from tile drains underlying an intensively managed grassland area in the Lough Neagh catchment. After membrane filtration the drainage water was recirculated through the reverse osmosis module while the permeate was removed from the system. During a single passage across the reverse osmosis membrane, 20% of the sample was discarded as pure water while the remaining 80% of the sample was pumped back to the reverse osmosis cartridge. Recirculation was continued, with the addition of an intermediate sodium ion-exchange step to prevent the precipitation of insoluble (largely calcium and magnesium) salts, until the volume was reduced to 2.5 l. The recovery of soluble organic phosphorus based on the original sample concentration was almost 93%. A further tenfold increase in concentration was achieved without salt precipitation or loss of soluble organic phosphorus by vacuum-assisted rotary evaporation. The mild, efficient concentration process developed a soluble organic phosphorus concentrate suitable for chemical fractionation and algal availability studies.

Perchlorate (0–75 μg) can be determined spectrophotometrically at 292 nm after extraction of protriptylinium perchlorate into ethyl acetate. The effects of pH and diverse anions are reported. The system has been applied to the determination of perchlorate in samples of potassium chlorate after prior selective destruction of chlorate.

Bismuth (0–300 μg) can be determined spectrophotometrically at 482 nm after its extraction as protriptylinium tetraiodobismuthate(III) into chloroform. The effects of reagent conditions and diverse ions are reported. The system has been applied to the determination of bismuth in pharmaceutical samples.

Rhenium (0–20 μg) may be determined as perrhenate spectrophotometrically at 362 nm after its extraction at pH 4 with amiloride hydrochloride into 4-methyl-2-pentanone. The relative standard deviation for 7 determinations of 10 μg of perrhenate is 1.5%. The effects of pH and diverse ions are reported. Only perchlorate, periodate and iodide interfere seriously. The system has been applied to the determination of rhenium on alumina and on carbon catalysts.

Chromium(VI) ($500 μg dichromate) can be determined spectrophotometrically at 365 nm after its extraction as protriptylinium dichromate into acetone-chloroform (1:1, vv). The effects of acidity, diverse ions and masking studies are reported. The relative standard deviation for determination of 200 μg of dichromate is 0.9% (n = 7). The system has been applied to the Spectrophotometric determination of chromium in steels (0.03–4%).

A flow-injection manifold has been developed for the spectrophotometric determination of manganese(VII) at 548 nm after extraction into chloroform of the ion-associate, benzyltributylammonium permanganate. The carrier stream was a pH 6 buffer containing 10% (w/v) ammonium fluoride and the reagent stream was 0.10% (w/v) benzyltributylammonium chloride. The injection rate was 20 h −1 . The calibration graph is linear up to 25 μg ml −1 and the detection limit (3 × baseline noise) is 0.91 μg ml −1 Mn(VII), based on 250-μl injection volumes. The system has been aplied to the determination of manganese in steels and a cupro-nickel alloy.

Chromium(VI) (–100 μg) can be determined spectrophotometrically at 365 nm after its extraction as benzyltributylammonium dichromate into chloroform. The effects of acidity, diverse ions and masking studies are reported.

Raman spectroscopy with far-red excitation has been used to study seized, tableted samples of MDMA (N-methyl-3,4-methylenedioxyamphetamine) and related compounds (MDA, MDEA, MBDB, 2C-B and amphetamine sulfate), as well as pure standards of these drugs. We have found that by using far-red (785 nm) excitation the level of fluorescence background even in untreated seized samples is sufficiently low that there is little difficulty in obtaining good quality data with moderate 2 min data accumulation times. The spectra can be used to distinguish between even chemically-similar substances, such as the geometrical isomers MDEA and MBDB, and between different polymorphic/hydrated forms of the same drug. Moreover, these differences can be found even in directly recorded spectra of seized samples which have been bulked with other materials, giving a rapid and non-destructive method for drug identification. The spectra can be processed to give unambiguous identification of both drug and excipients (even when more than one compound has been used as the bulking agent) and the relative intensities of drug and excipient bands can be used for quantitative or at least semi-quantitative analysis. Finally, the simple nature of the measurements lends itself to automatic sample handling so that sample throughputs of 20 samples per hour can be achieved with no real difficulty.

A short overview is presented covering the actual and potential use of cyclodextrins and some of their derivatives in analytical chemistry. The contributions in separation science, including HPLC, GC, CE and MEKC are noted, together with applications in circular dichroism and luminescence techniques, including fluorescence and phosphorescence.