49000 HPLC kit benzodiazepines TCA clozapine serum plasma

Benzodiazepines and Tricyclic Antidepressants in Serum/Plasma - HPLC

Order no.: 49000
100 Tests
  • Alprazolam
  • Amitriptyline
  • Bromazepam
  • Chlordiazepoxide
  • Clobazam
  • Clomipramine
  • Clonazepam
  • Clozapine
  • Desipramine
  • Diazepam
  • Doxepin
  • Flunitrazepam
  • Imipramine
  • Maprotiline
  • Nitrazepam
  • Norclobazam
  • Norclomipramine
  • Norclozapine
  • Nordiazepam
  • Nordoxepin
  • Nortriptyline
  • Oxazepam
  • Trimipramine

All important benzodiazepines, TCA & metabolites
One sample preparation for both substance groups
Identical HPLC conditions, one HPLC column and mobile phase


Clinical relevance

Benzodiazepines are a large group of psychotropic drugs with a similar chemical structure. They are the most important representatives of sedatives and sleeping pills. Some are also used as antiepileptic drugs, muscle relaxants, and as analgesics in administering general anaesthesia. In the case of alcohol withdrawal treatments they facilitate weaning, although the danger of an alternative dependence exists. The various benzodiazepines are metabolised at different rates, and in some cases it is not until the metabolites form (e.g. desalkylflurazepam) that they become therapeutically effective.

Tricyclic antidepressants (TCAs) are used to treat psychological conditions such as anxiety, pain syndromes, and phobias, and produce a positive mood enhancing effect. Their pharmacological effect is based on increasing the concentration of dopamine, noradrenalin and serotonin in the synaptic cleft by inhibiting the degradation or reuptake of these neurotransmitters.

By regularly determining the plasma levels side effects can be minimised and overdoses can be avoided. Also, patient compliance can be checked to help ensure optimal therapy outcomes.


Product advantages

  • Covers all important benzodiazepines, TCA & metabolites
  • Simultaneous sample preparation for both substance groups
  • Identical HPLC column and mobile phase for all parameters


This kit is designed for the determination of the main therapeutic benzodiazepines and tricyclic antidepressants and their relevant metabolites with a single sample preparation. The two substance groups are assayed in two chromatographic runs on an isocratic HPLC system with UV detector. The analytes are quantified by the inclusion of two specifically synthesized internal standards which themselves are not used as medication and therefore do not lead to interferences. By means of selective solid phase extraction, the sample preparation eliminates interfering co-eluants and ensures reproducible and reliable results.


Technical Data

Method of Analysis


Number of Tests



Alprazolam, Amitriptyline, Bromazepam, Chlordiazepoxide, Clobazam, Clomipramine, Clonazepam, Clozapine, Desipramine, Diazepam, Doxepin, Flunitrazepam, Imipramine, Maprotiline, Nitrazepam, Norclobazam, Norclomipramine, Norclozapine, Nordiazepam, Nordoxepin, Nortriptyline, Oxazepam, Trimipramine

Analysis Time

28 min (BZD), 25 min (TCA)

Limit of quantification

1.5–27 ng/ml; The limit of quantification depends on the detector employed.


Entire therapeutic range


86–122 %


CV = 0.7–4.5 %


CV = 1.9–6 %



Pre-analytic Treatment

The patient samples are stable for at least 24 hours if stored in a dark and cool (+4 °C) place. For longer storage keep samples below -20 °C. Use polypropylene vials for transport.

Sample Preparation


  • Precondition the Sample Clean Up Columns with 2 x 1 ml of each Equilibration Buffers 1 and 2.
  • Add 1 ml serum/plasma (calibrator/control) and 100 µl Internal Standard to the Sample Clean Up Column, mix briefly.
  • Draw complete sample through Sample Clean Up Column by centrifugation or suction, discard effluent.


  • Draw 2 x 1 ml Wash Buffer through Sample Clean Up Column by centrifugation or suction, discard effluents.


  • Elute first the benzodiazepines and then the tricyclic antidepressants with 400 µl of appropriate Elution Buffer.
  • Add 200 µl ultrapure water (HPLC grade) to each eluate.
  • Inject 50 µl of the diluted eluate into the HPLC system.

Sample Stability

Prepared samples can be kept at room temperature for 3 days or at +2 to +8 °C for 5 days, light protected in glass vials. For longer storage keep samples below -18 °C (up to 2 weeks).

Additional Info

Any isocratic HPLC system with UV detector is suitable.

Injection Volume

50 µl

Flow rate

0.6 ml/min



Column temperature

ambient (~ 25 °C)


210 nm

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

Components available separately

Mobile Phase

Order no.: 49001

Internal Standard

Order no.: 49004

Equilibration Buffer 1

Order no.: 49005

Equilibration Buffer 2

Order no.: 49006

Wash Buffer

Order no.: 49007

Elution Buffer 1

Order no.: 49009

Elution Buffer 2

Order no.: 49010

Sample Clean Up Columns

Order no.: 49008