92917 LCMS TDM Series A Benzodiazepines1

Parameter Set Benzodiazepines 1 - LC-MS/MS

Order no.: 92917
  • 1-OH-midazolam
  • Chlordiazepoxide
  • Clobazam
  • Demoxepam
  • Diazepam
  • Medazepam
  • Midazolam
  • Norclobazam
  • Nordiazepam
  • Oxazepam
  • Prazepam
  • Temazepam
  • Tetrazepam

Encompasses 13 analytes
3PLUS1® Multilevel Calibrator Set available
Part of the MassTox® TDM Series A


Clinical relevance

Benzodiazepines (BZD) are a group of psychoactive drugs with similar structures that are classified as sedatives. By virtue of their high lipophilicity they penetrate the blood-brain barrier easily and, after being resorbed, quickly reach the central nervous system, where they enhance the impact of the inhibiting neurotransmitter GABA. Besides anxiolytic and sedative effects, BZD also have anti-aggressive, hypnotic, muscle relaxant and anticonvulsive properties. The predominance of the individual effects varies with the special structures of the benzodiazepines and the administered dose. BZD in blood are present mostly bound nonspecifically to plasma proteins. They are metabolised mainly by the liver. The resulting metabolites are mostly pharmacologically active themselves, and in some cases they represent the actual active substance, e.g. nordiazem being metabolised from diazepam or clorazepate. The plasma elimination times are highly variable: from a few hours (midazolam) to several days (clobazam). The metabolites frequently have longer half-lives than the parent substance, so an enrichment of therapeutically effective substances in the blood can occur.


Product advantages

With the Parameter Set Benzodiazepines 1 in serum/plasma, 13 different drugs can be measured quickly and efficiently using LC-MS/MS. Due to the careful optimisation of all kit components as well as the chromatographic separation, matrix effects (“ion suppression”) are minimised and the robustness of the method is enhanced. Sample preparation is based on a protein precipitation step. The use of stable isotopically labelled (deuterated) and co-eluting internal standards as well as 3PLUS1® multilevel calibrators ensures high precision and the reproducible and reliable quantification of the analytes. The method is comprehensively validated.

The Parameter Set is a part of the Series A modular system, which enables the analysis of all parameters without switching column or changing the mobile phases, thereby minimising required workload in the laboratory. The Basic Kit A contains all components required for sample preparation and all necessary mobile phases. The MasterColumn® A is the analytical column used for the determination of all Series A analytes. Our portfolio contains further MassTox® Parameter Sets

For the analysis you require the MassTox® TDM Basic Kit A, the specifc MassTox® TDM Parameter Set and the analytical column MassTox® TDM MasterColumn® A.


Technical Data

Method of Analysis



1-OH-midazolam, Chlordiazepoxide, Clobazam, Demoxepam, Diazepam, Medazepam, Midazolam, Norclobazam, Nordiazepam, Oxazepam, Prazepam, Temazepam, Tetrazepam

Analysis Time

3 min

Limit of quantification

3 – 40 µg/l


up to 1000–5050 μg/l


87 – 107 %


CV = 2 – 5 %


CV = 2 – 7 %



Sample Preparation

  • Add 800 μl Internal Standard mix to 12 ml Precipitation Reagent to form mixture A
  • Pipette 50 μl sample/calibrator/MassCheck® control into a 1.5 ml reaction vial
  • Add 25 μl Extraction Buffer, mix briefly (vortex) and incubate 2 min.
  • Add 250 μl of mixture A and mix 30 s minimum (vortex) and centrifuge 5 min.
  • Dilute the supernatant with Dilution Buffer prior to injection depending on the instrument sensitivity

Sample Stability

Samples are stable up to 1 week at +2 to +8 °C. For longer storage periods keep samples frozen below -18 °C.

Injection Volume

0.2 – 50 µl


Isocratic (25 % Mobile Phase 1; 75 % Mobile Phase 2)


ESI positive



Additional Info

We recommend to set the scan time to a value that allows to achieve a minimum of 10 data points over the whole peak width.

Please note

The freely available information on this website, in particular on the sample preparation, are not sufficient to work with our products. Please read instructions and warning notices on products and/or instruction manuals.

Kit Components


Calibrators available separately


Controls available separately