A blue luminescent MOF as a rapid turn-off/turn-on detector for H2O, O2 and CH2Cl2, MeCN: ∞³[Ce(Im)3ImH]·ImH.

The blue emitting luminescent MOF ∞³[Ce(Im)3ImH]·ImH forms a 3D-framework with Kagomé net topology. The framework exhibits an intense blue luminescence which can be retained upon activation of the MOF with the formula ∞³[Ce(Im)3ImH]. The luminescence is metal-based due to parity-allowed 5d-4f-transitions. Time-dependent investigations of the interaction with liquid and gas analytes show that the MOF ­ by utilising 5d-4f-transitions of Ce(3+) ­ can be used as a high-speed "turn-off" detector for water and oxygen in dry air. Other protic or polar solvents, like methanol, acetone or pyridine, which also show a "turn-off"-effect can be distinguished from water-detection either on a time scale (ranging up to 250,000 : 1) or a shift of the chromaticity, the latter being pronounced for MeOH. The fast time-dependent decrease of the luminescence intensity for water arises from an extremely fast hydrolysis and is irreversible. Polar aprotic molecules like dichloromethane and acetonitrile can also result in a "turn-on"-effect of the luminescence intensity due to their behaviour as additional sensitizers for Ce(3+)-emission. We conclude that the cerium-MOF can be utilised in gas and liquid sensing applications as a detector material for water and oxygen in dry air. The luminescence is intense with good quantum yield between 55% (as-synthesised) and 36% (activated). This implies that only milligram amounts of the material are needed to detect the analyte species and is especially useful, as the MOF can be directly used as-synthesised for water detection in applications for which an irreversible signal change is desired, e.g. preventing a signal change upon unwanted re-drying.

Lanthanide based tuning of luminescence in MOFs and dense frameworks--from mono- and multimetal systems to sensors and films.

This feature article focuses on tuning options of photoluminescence properties of lanthanide containing Metal-Organic Frameworks (MOFs) and Dense Frameworks by selection of an appropriate set of metal ions together with suitable ligands. In addition to lanthanide-only systems, frameworks with main group and transition metal ions that are heterometallic or co-doped with variable lanthanide content offer excellent tuning options for luminescence. The MOF feature porosity enables further applications such as sensors for a large number of chemical analytes by selective influences on the luminescence upon contact. The application of functional thin films marks the most recent development of this amazingly growing field, involving processing and structuring.

Opiate detection in saliva and urine--a prospective comparison by gas chromatography-mass spectrometry.

UNLABELLED: There is an increasing interest in saliva as an alternative analytic body fluid. OBJECTIVE: This study sought to determine the correlation of opiates analyzed in saliva and corresponding urine. METHODS: A total of 130 adequate and 24 inadequate samples were collected from patients participating in drug withdrawal therapy. To obtain saliva from the oral cavity, a newly developed collection device (Clin Rep), consisting of a treated cotton roll and a centrifugation vial with a filter inset, was tested. For the preparation of a purified solution of urine, liquid extraction was used. Solid phase extraction was utilized to prepare the saliva samples. For the detection by gas chromatography-mass spectrometry, an appropriate derivatization was necessary using N-methyl-N-(trimethylsilyl)trifluoroacetamide. The retention times were compared with defined standard solutions. The obtained mass spectra showed a characteristic fragmenting pattern and offered a reliable identification. RESULTS: The concordance of the analytic results of the saliva samples with urine was 93% for a decision limit of 100 ng/mL and 98% for a decision limit of 300 ng/mL (DHHS opiate cutoff) in urine. CONCLUSIONS: Saliva, of adequate amount in 85% of samples, may be appropriate for analysis of drugs of abuse.

Determination of the heroin metabolite 6-monoacetyl-morphine in urine by high-performance liquid chromatography with electrochemical detection.

A procedure has been developed for detection and quantitation of 6-monoacetylmorphine (6-MAM), the specific metabolite of heroin in human urine. 6-MAM was isolated by solid-phase extraction, and the extracts were analyzed by high-performance liquid chromatography with electrochemical detection in the oxidizing mode. Good linearity was obtained in the concentration range 10-250 ng/mL. Concentrations of 2 ng 6-MAM/mL can be detected using a 2-mL sample of urine. The method has been verified in urine samples of heroin abusers.

[Change in congener analysis caused by percutaneous absorption of propanol-containing antiseptics]. / Veränderung von Begleitstoffanalysen durch percutane Resorption propanolhaltiger Antiseptika.

According to the forensic literature, an alteration of blood alcohol concentration through alcohol disinfection before venepuncture is unlikely, however, percutaneous resorption of alcohol containing antiseptics is well documented. There are no investigations available, elucidating to what extent this is also correct for congener alcohols, particularly propanol-1/-2, which have serum levels in range of mg/l. In experiments with surgical hand and local skin disinfection, carried out with and without oral alcohol, relevant levels of propanol-1/-2 between 0.2 and 2 mg/l were measured. We conclude, that the routine clinical use of antiseptics is able to alterate and to falsify congener levels and can lead to incorrect interpretation of congener analysis.

2, 2-Diethyl-4-pentenamide, a sedative of new importance.

The introduction of prescription duty in the F.R. of Germany for bromo-ureas has led to a substitution by 2,2-diethyl-4-pentenamide in some common sedatives. Extraction of this drug and its main metabolite from biological material and detection by TLC and GLC is described. Concentrations is blood and urine are determined after therapeutic dosage and in cases of chronic and acute intoxications including monitoring. Post mortem levels in specimen and body fluids after suicides are reported.