Pharmacokinetics and pharmacodynamics of nasally delivered midazolam.

AIMS: To investigate the pharmacokinetics and pharmacodynamics of nasal formulations containing midazolam (5-30 mg ml(-1)) complexed with cyclodextrin. METHODS: An open-label sequential trial was conducted in eight healthy subjects receiving single doses of 1 mg and 3 mg intranasally and 1 mg midazolam intravenously. Pharmacokinetic parameters were obtained by non-compartmental and two-compartmental models. Pharmacodynamic effects of midazolam were assessed using VAS and a reaction time test. RESULTS: Mean bioavailability of midazolam after nasal administration ranged from 76 +/- 12% to 92 +/- 15%. With formulations delivering 1 mg midazolam, mean C(max) values between 28.1 +/- 9.1 and 30.1 +/- 6.6 ng ml(-1) were reached after 9.4 +/- 3.2-11.3 +/- 4.4 min. With formulations delivering 3 mg midazolam, mean C(max) values were between 68.9 +/- 19.8 and 80.6 +/- 15.2 ng ml(-1) after 7.2 +/- 0.7-13.0 +/- 4.3 min. Chitosan significantly increased C(max) and reduced t(max) of midazolam in the high-dose formulation. Mean ratios of dose-adjusted AUC after intranasal and intravenous application for 1'-hydroxymidazolam were between 0.97 +/- 0.15 and 1.06 +/- 0.24, excluding relevant gastrointestinal absorption of intranasal midazolam. The pharmacodynamic effects after the low-dose nasal formulations were comparable with those after 1 mg intravenous midazolam. The maximum increase in reaction time by the chitosan-containing formulation delivering 3 mg midazolam was greater compared with 1 mg midazolam i.v. (95 +/- 78 ms and 19 +/- 22 ms, mean difference 75.5 ms, 95% CI 15.5, 135.5, P < 0.01). Intranasal midazolam was well tolerated but caused reversible irritation of the nasal mucosa. CONCLUSIONS: Effective midazolam serum concentrations were reached within less than 10 min after nasal application of a highly concentrated midazolam formulation containing an equimolar amount of the solubilizer RMbetaCD combined with the absorption enhancer chitosan.

Validation of an ion mobility spectrometry (IMS) method for the detection of heroin and cocaine on incriminated material.

The validation of a qualitative ion mobility spectrometry (IMS) procedure for the detection of trace amounts of heroin and cocaine on incriminated material using a vacuum cleaner for sampling is presented. The limit of detection, the limit of decision, selectivity and robustness were determined. As an approach, robustness was determined using ionizational interferences and matrix effects. By using this simple sampling procedure, a positive result for incriminated clothes needs a contamination of 250ng cocaine and 1000ng heroin, respectively.

Quantification of benzodiazepines in whole blood and serum.

A high-performance liquid chromatography method for the determination of benzodiazepines and their metabolites in whole blood and serum using mass spectrometry (MS) and photodiode array (PDA) detection is presented. The combination of both detection types can complement each other and provides extensive case relevant data. The limits of quantification (LOQ) with the MS detection lie between 2 and 3 microg/l for the following benzodiazepines or metabolites: 7-amino-flunitrazepam, alprazolam, desalkyl-flurazepam, desmethyl-flunitrazepam, diazepam, flunitrazepam, flurazepam, alpha-hydroxy-midazolam, lorazepam, midazolam, nitrazepam, nordazepam and oxazepam, respectively 5 microg/l for lormetazepam and 6 microg/l for bromazepam. The LOQ of clobazam determined with the PDA detector is 10 microg/l. A convenient approach for determining the measurement uncertainty of the presented method--applicable also for other methods in an accreditation process--is presented. At low concentrations (<10 microg/l), measurement uncertainty was estimated to be about 50%, and at concentrations >180 microg/l, it was estimated to be about 15%. One hundred and twenty-eight case data acquired over 1 year are summarised.

Isolation of Delta9-THCA-A from hemp and analytical aspects concerning the determination of Delta9-THC in cannabis products.

A simple procedure based on a common silica gel column chromatography for the isolation of Delta9-tetrahydrocannabinolic acid A (Delta9-THCA-A) from hemp in a multi-milligram scale is presented. Further, the decarboxylation reaction of Delta9-THCA-A to the toxicologically active Delta9-tetrahydrocannabinol (Delta9-THC) at different analytical and under-smoking conditions is investigated. Maximal conversion in an optimised analytical equipment yields about 70% Delta9-THC. In the simulation of the smoking process, only about 30 % of the spiked substance could be recovered as Delta9-THC.