The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Principal component analysis (PCA) loading plots were used to elucidate key differences between two-dimensional high performance liquid chromatography (2D-HPLC) fingerprint data from samples collected from stages along the Papaver somniferum industrial process chemistry workflow. Data reduction was completed using a 2D-HPLC peak picking approach as a precursor to chemometric analysis. Using comparisons...
The selection of two orthogonal columns for two-dimensional high performance liquid chromatography (LC×LC) separation of natural product extracts can be a labour intensive and time consuming process and in many cases is an entirely trial-and-error approach. This paper introduces a blind optimisation method for column selection of a black box of constituent components. A data processing pipeline, created...
The selection of two high performance liquid chromatography (HPLC) columns with vastly different retention mechanisms is vital for performing effective two-dimensional (2D-) HPLC. This paper reports on a systematic method to select a pair of HPLC columns that provide the most different separations for a given sample. This was completed with the aid of a HPLC simulator that predicted retention profiles...
Previous applications of manganese(IV) as a chemiluminescence reagent have required the use of formaldehyde to enhance the emission intensity to analytically useful levels. However, this known human carcinogen (by inhalation) is not ideal for routine application. A wide range of alternative enhancers have been examined but to date none have been found to provide the dramatic increase in chemiluminescence...
Herein we explore modern fabrication techniques for the development of chemiluminescence detection flow-cells with features not attainable using the traditional coiled tubing approach. This includes the first 3D-printed chemiluminescence flow-cells, and a milled flow-cell designed to split the analyte stream into two separate detection zones within the same polymer chip. The flow-cells are compared...
Heroin (3,6-diacetylmorphine) and several important extraction and synthesis impurities (morphine, 6-monoacetylmorphine, codeine and 6-acetylcodeine) were determined in illicit drug samples, using high performance liquid chromatography with ‘parallel segmented flow’, which enabled the simultaneous use of three complementary modes of detection (UV-absorbance, tris(2,2′-bipyridine)ruthenium(III) chemiluminescence...
We present an exploration of the chemiluminescence from reactions of benzylpiperazines and phenylpiperazines with tris(2,2′-bipyridine)ruthenium(III). The selectivity of the reagent towards these compounds was found to be highly dependent upon the pH of the solution, and the relative emission intensity was strongly influenced by electron donating or withdrawing substituents on the phenyl or benzyl...
We have explored the chemiluminescence response of amino acids and related compounds (including the tripeptide glutathione, and disulfides: cystine, homocystine and glutathione disulfide) with several new adaptations of the permanganate and tris(2,2′-bipyridine)ruthenium(III) ([Ru(bipy) 3 ] 3+ ) reagents and a recently developed colloidal manganese(IV) system. The selectivity of the...
A simple controlled chemical reduction of 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) and related nitramine compounds with zinc amalgam generates species that elicit intense chemiluminescence with tris(2,2′-bipyridine)ruthenium(III), which extends this widely utilised chemiluminescence reagent to a new class of analyte and presents a sound chemical basis for a screening test for nitramine high explosives...
Differences between alkyl, dipole–dipole, hydrogen bonding, and π–π selective surfaces represented by non-resonance and resonance π-stationary phases have been assessed for the separation of ‘Ristretto’ café espresso by employing 2DHPLC techniques with C18 phase selectivity detection. Geometric approach to factor analysis (GAFA) was used to measure the detected peaks (N), spreading angle (β), correlation,...
In this study, an activity based screening technique combining two-dimensional liquid chromatography (2DHPLC) with UV-absorbance and chemiluminescence detection was applied to study “Ristretto”, “Decaffeinatto” and “Volluto” espresso coffees. This technique, which coupled the separation power of 2DHPLC with the sensitivity and selectivity of the chemiluminescence detection, offers great potential...
Ruthenium complexes containing 4,7-diphenyl-1,10-phenanthroline disulfonate (bathophenanthroline disulfonate; BPS) ligands, Ru(BPS) 34− , Ru(BPS) 2 (bipy) 2− and Ru(BPS)(bipy) 2 , were compared to tris(2,2′-bipyridine)ruthenium(II) (Ru(bipy) 32+ ), including examination of the wavelengths of maximum absorption and corrected emission intensity, photoluminescence...
The antioxidant profiles of various espresso coffees were established using HPLC with UV-absorbance detection and two rapid, simultaneous, on-line chemical assays that enabled the relative reactivity of sample components to be screened. The assays were based on (i) the colour change associated with reduction of the 2,2′-diphenyl-1-picrylhydrazyl radical (DPPH); and (ii) the emission of light (chemiluminescence)...
Acidic potassium permanganate chemiluminescence was explored as a sensitive and selective mode of detection for phenolic phenethylamines (adrenergic amines) in consumer products containing Citrus aurantium extracts. Nine commercially available weight-loss products were analysed using rapid reversed-phase chromatography with a monolithic column (separation time of 4min). The results were in good agreement...
High-performance liquid chromatography (HPLC) with tris(2,2′-bipyridyl)ruthenium(II) chemiluminescence detection methodology is reported for the determination of the atypical antipsychotic drug quetiapine and the observation of its major active and inactive metabolites in human urine and serum. The method uses a monolithic chromatographic column allowing high flow rates of 3mLmin −1 enabling...
A sequential injection analysis procedure with dual-reagent chemiluminescence detection was applied to the screening of street drug seizure samples for the presence of heroin. The chemiluminescence reagents (acidic potassium permanganate and tris(2,2′-bipyridine)ruthenium(III)) were aspirated from either side of a sample aliquot that was sufficiently large to prevent interdispersion of the reagent...
An investigation into the chemiluminescence of fourteen organic acids and tris(2,2′-bipyridyl)ruthenium(II) was undertaken. Particular emphasis was placed upon the method of production of the reagent, tris(2,2′-bipyridyl)ruthenium(III), with cerium(IV) sulfate, potassium permanganate, lead dioxide and electrochemical generation. Analytically useful chemiluminescence was observed when Ce(IV) or potassium...
We present the results of our investigations into the use of soluble manganese(IV) as a chemiluminescence reagent, which include a significantly faster method of preparation and a study on the effect of formaldehyde and orthophosphoric acid concentration on signal intensity. Chemiluminescence detection was applied to the determination of 16 analytes, including opiate alkaloids, indoles and analytes...
The oxidation of selected clinically important neurotransmitter metabolites with acidic potassium permanganate in the presence of polyphosphates evokes chemiluminescence of sufficient intensity to enable the sensitive determination of these species. Limits of detection for 5-hydroxyindole-3-acetic acid (5-HIAA), vanilmandelic acid (VMA; α,4-dihydroxy-3-methoxybenzeneacetic acid), 4-hydroxy-3-methoxyphenylglycol...
This paper reviews recent applications of capillary electrophoresis to forensic drug analysis and covers the literature since 2001. A brief overview of capillary electrophoresis is followed by a discussion of analytical applications which have been categorized into two sections: (i) drug seizures and non-biological samples, and (ii) forensic toxicology and biological samples.
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.