Implementation of an integrated glucose POCT system

In response to a change of the Belgian National Directives whereby hospital laboratories became responsible for all point-of-care testing (POCT) performed within hospital walls a standardized and automated POC glucose-testing system was implemented in our hospital. The system consists of 50 AccuCheck Inform instruments (Roche Diagnostics, Vilvoorde, Belgium), 50 docking stations, a DataCare Server, and connections to the medical laboratory information system (MOLIS, Sysmex, Barchon, Belgium) and to the hospital information system. Implementation involved many parties and extensive preparation and communication. Key issues were bar-coded patient and user identification, training, and responsibilities. One year after the hospital wide implementation of this system the quality of POC glucose testing has significantly increased, thereby improving patient safety. This study describes a stepwise change over involving the medical laboratory and with a focus on hands-on quality.Presented at the ninth conference on Quality in the Spotlight, 18–19 March 2004, Antwerp, Belgium.     

Synthesis of the dibenzo[f,h]phthalazine and dibenzo[f,h]cinnoline skeleton via a ‘Suzuki-Pd-catalyzed intramolecular arylation’ and a ‘Suzuki-Pschorr’ approach

Palladium-catalyzed intramolecular arylation of 2-benzyl-5-(2-bromophenyl)-4-phenylpyridazin-3(2H)-one yielded hitherto unknown 2-benzyldibenzo[f,h]phthalazin-1(2H)-one. The synthesis of this new tetracyclic pyridazinone from 2-benzyl-5-(2-aminophenyl)-4-phenylpyridazin-3(2H)-one via a Pschorr type reaction was also investigated. Similarly, the construction of 2-methyldibenzo[f,h]cinnolin-3(2H)-one from 2-methyl-5-(2-bromophenyl)-6-phenylpyridazin-3(2H)-one and 2-methyl-5-(2-aminophenyl)-6-phenylpyridazin-3(2H)-one is also reported. Removal of the N-benzyl protective group of 2-benzyl-dibenzo[f,h]phthalazin-1(2H)-one with AlCl₃ yielded unsubstituted dibenzo[f,h]phthalazin-1(2H)-one.     

Pd-catalyzed intramolecular direct arylations at high temperature

Pd-catalyzed cyclodehydrohalogenation involving oxidative addition of aromatic C-Br or activated azaheteroaromatic C-Cl bonds and C(sp²)-H activation have been investigated at high reaction temperatures (180-200 °C). This allowed the fast (10-30 min) synthesis of a variety of azaheteroaromatic ring systems (dibenzo[f,h]phthalazine, dibenzo[f,h]cinnoline, benzofuro[2,3-d]pyridazine, 5H-pyridazino[4,5-b]indole, 7H-indolo[2,3-c]quinoline and 5H-δ-carboline) in moderate to good yields.     

Carboxylic‐Acid‐Passivated Metal Oxide Nanocrystals: Ligand Exchange Characteristics of a New Binding Motif

Ligand exchange is central in the processing of inorganic nanocrystals (NCs) and requires understanding of surface chemistry. Studying sterically stabilized HfO₂ and ZrO₂ NCs using ¹H solution NMR and IR spectroscopy as well as elemental analysis, this paper demonstrates the reversible exchange of initial oleic acid ligands for octylamine and self‐adsorption of oleic acid at NC surfaces. Both processes are incompatible with an X‐type binding motif of carboxylic acids as reported for sulfide and selenide NCs. We argue that this behavior stems from the dissociative adsorption of carboxylic acids at the oxide surface. Both proton and carboxylate moieties must be regarded as X‐type ligands yielding a combined X₂ binding motif that allows for self‐adsorption and exchange for L‐type ligands.     

The Forgotten Pyrazines: Exploring the Dakin–West Reaction

Pyrazines are an underreported class of N-heterocycles available from nitrogen-rich biomass presenting an interesting functional alternative for current aromatics. In this work, access to pyrazines obtained from amino acids by using the 90 year old Dakin–West reaction was explored. After a qualitative screening several functional proteinogenic amino acids proved good substrates for this reaction, which were successfully scaled to multigram scale synthesis of the corresponding intermediate α-acetamido ketones. Subsequently, the conditions towards pyrazine formation using δ-amino-levulinic acid were optimized, and these were employed to synthesize a relevant set of five functional dimethylpyrazines in high purity. These pyrazines can be considered a versatile toolbox of aromatic building blocks for a wide range of applications, such as in the synthesis of polymers or metal–organic frameworks.     

Fourier transform laser microprobe mass spectrometry for the molecular identification of inorganic compounds

This study attempted to determine the molecular composition of inorganic analytes at the surface of solids by Fourier transform laser microprobe mass spectrometry (FT LMMS) with an external ion source. A database was established from the analysis of pure compounds. FT LMMS uses a similar ionization as the older LMMS instruments with time-of-flight (TOF) mass analyzer. However, apart from the mass resolution, the mass spectral patterns can be significantly different in FT LMMS compared to TOF LMMS. FT LMMS yields detailed information on the analyte by means of structural fragments, enabling us to specify the main building blocks, as well as adduct ions, consisting of the analyte molecule and a stable ion. Hence, deductive reasoning allows tentative characterization of the analogs without reference spectra, except for compounds with the same elements in different stoichiometries. In that case comparative data are needed.     

Towards logistics systems parameter optimisation through the use of response surfaces

Logistics systems have to cope with uncertainties in demand, in lead times, in transport times, in availability of resources and in quality. Management decisions have to take these uncertainties into consideration. An evaluation of decisions may be done by means of simulation. However, not all stochastic phenomena are of equal importance. By design of simulation experiments and making use of response surfaces, the most important phenomena are detected and their influence on performance estimated. Once the influence of the phenomena is known, this knowledge may be used to determine the optimal values of some decision parameters. An illustration is given on how to use response surfaces in a real-world case. A model is built in a logistics modelling software. The decision parameters have to be optimised for a specific objective function. Experiments are run to estimate the response surface. The validity of the response surface with few observations is also tested.     

A general method for the computation of probabilities in systems of first order chemical reactions

We present a general method for the computation of molecular population distributions in a system of first-order chemical reactions. The method is based on the observation that the molecules in first-order reactions do not interact with each other. Therefore, the population distributions are a convolution of densities for one molecule. With this method one can study reactions involving any number of molecules. Such analysis is demonstrated on several examples, including an enzyme catalyst reaction and a first-order reaction chain.