MicroSolv Technologies Knowledge Base


Browse Ask a Question

1,4-Benzodiazepines in Urine

Reference Number: AA-02323 Created: 05/08/2014 12:38 PM Last Updated: 04/09/2019 11:49 AM

LC-MS method with SPE

 1,4-Benzodiazepinein Urine

Peak: 1. Temazepam 301.0739 m/z [M+H]+

   2. Diazepam 285.0790 [M+H]+

    3. Nordiazepam 271.0633 [M+H]+

    4. Midazolam 326.0855 [M+H]+

     Method Conditions

      Column: Cogen Diol, 4.4µm 1 00Å
      Catalog No.: 40060-05P-2
      Dimensions: 2.1 x 50 mm
      Solvents: A: DI  H20  /  0 .1% formic  Acid (v/v)
                      B: Acetonitrile/ 0.1% formic Acid (v/v)
      Gradient: (Fig. A) (Fig. B)

              time (min.)     %B         time (min.)    %B        

                           0       85            0               10
  6       70            6               10
  7       20            7               50
  9       20            9               50
        10     85            10             10

      Post time: 3 min
        Injection vol.: 1 µL 
      Flow rate: 0.4 ml/min 
      Detection: ESI – POS  Perki Elme AxIO 2 TOF mass spectrometer
      Flow rate: 0.4 ml/min 
       Samples: Extraction method: Spike urine  sampl was loaded into SPcartridge I (Clean Screen Xcel purchased from UCT BristolPA, USA) and eluted with 0.78 mL of acetonitrile, 200 microL of 2-propanol, 20 microL of ammonia. After the elution, thsampl wadried unde N2 gas and dissolved in 100 microof 50% methanol / 50% DI H2O / 0.1% formic acid. 

            Before injection, the 10 ppm spiked sample was filtered through a 0 .45µm nylon syringe filter (MicroSolv Tech Corp).


The Cogent Diol column was used in analysis  of 1,4-benzodiazepines in urine  samples  after SPE extraction using  two types of retention modes.  Four  available compounds were  well  retained and separated in both modes;  however, the retention order was changed depending on the gradient used. It is worth noticing that the peak intensities were  three times higher when  using  Gradient A (ANP mode) compared to Gradient B (RP mode).

Notes: Benzodiazepines are prescribed for conditions such as anxiety disorders, insomnia, seizures,  and alcohol withdrawal. However, they also have potential for abuse as recreational drugs.


     © Copyright MicroSolv Technology Corporation, all rights reserved.

No 306 Benzodiazepines.pdf 0.3 Mb Download File
Info Ask a Question 
Your Email: Subject: Question: