Two-dimensional gas chromatography with time of flight mass spectrometer facility (GC-GC-TOF-MS)

         Kindly download Material Safety Data sheet and submit the hardcopy of filled sheet along with your sample

  Instrument Details  

Make & Model : Leco, Pegasus 4D with Agilent 7890B GC
Available modes : Following injection modes are possible
(a) Liquid/gas injection
(b) Cooled injection system and thermal desorption unit (CIS-TDU)
(c) Headspace injection
(d) Stir bar sorptive extraction (twister) and solid phase micro-extraction (SPME)
(e) Pyrolysis

  Working Principle   

         It can perform all analysis that a typical GC-TOF-MS can perform. Its particular benefit is for analysis of organic compounds from complex mixtures and environmental samples where high end separation is involved. It involves two columns (that can achieve separation based on different attributes). A thermal modulator ensures cryo focusing of effluent from the first column before its release to the second column. The two-dimensional output helps in resolving the peak of target analytes even when matrix interferences are present. The enhanced spectral collection rate of the TOF-MS detector together with the software capabilities can help in de-convolution of co-eluting compounds.

  Technical Specifications   

Injection Mode:

The GC-GC-TOF-MS coupled with Gerstel Sampler can be operated routinely in the following injection modes:
        •  Liquid injection mode-Back injector: Only liquid injection is possible
     • Cooled injection system and thermal desorption unit (CIS-TDU)-Front injector: liquid injection; headspace injection, stir bar            sorptive extraction (twister) and solid phase micro-extraction (SPME)
        •  Pyrolysis mode


The columns currently equipped are:
        •  Primary Column: Rxi 5-MS (30 m)
        •  Secondary Column: Rxi 17Sil MS (2 m)
Although column change is possible, column change will not be done frequently. Analysis may be delayed if column change is required.

Special Features:

        •  When operated in 2-D mode, higher resolution can be achieved for complex samples
        •  Independent temperature programming for each of the columns can be done to enhance resolution.
        •  The MS is capable of collecting 20 full range spectra or more across a 50 ms chromatographic peak
        •  Higher dynamic range can be achieved due to software capabilities
        •  Higher sensitivity

    The system is particularly suitable for applications from following fields:


  Contact us   

         Room 114 A, CRNTS department
         Contact : 022-2159-6376
         Email Id :

  User Instructions   
• One sample refers to one injection in any of these modes. Multiple injections of the same sample will be treated as multiple samples. Delays may be involved if injector change is required for sample analysis.

• Charge for 2-dimensional (D) analysis will be same as 1-D; However no samples will be directly analyzed in 2-D mode before a 1-D run has been conducted. For similar type of samples, after 1 1-D run is done the remaining can be allowed directly in 2D.

Appointment: The users will be informed about their date and time-slot by email for submission of sample/s. If the day and time-slot is not suitable for you, an email request should be sent immediately for an alternate slot.

Sample Preparation:
         1. The sample should be dissolved in volatile organic solvents, preferably hexane or isooctane.
         2. Other solvents like, methanol, ethanol, ethyl acetate etc. can also be used.
         3. Solvents such as DMSO, THF and water are not acceptable.
         4. The sample should be free of particulates of size > 0.45 μm

Sample Submission: Samples are to be brought along on the date of your appointment for submission (Between 9:30 to 11 AM). The samples will be analyzed on the next day of submission.

Analysis results: After the sample analysis is complete the results will be sent through email. For large data files user may provide a blank CD for the data files.

Getting Back the samples: Users desiring to get back the samples need to mark on the form. Collect them from the lab between 9:30 AM to 11:00 AM after two-three days of completion of the work (intimated through mail) and uncollected samples will be disposed-off after ten days of intimation of the completion of the work and no reminders will be sent.

  Additional Instructions for the users   
1. The experimental data provided is only for research / development purposes. These cannot be used as certificates in legal disputes.

2. A maximum 3 samples will be analyzed against a single Registration Form.

3. The analytes expected in the samples should be clearly indicated and MSDS (Material Safety Data Sheet) should be given both for the samples and the analytes to indicate the toxicity.

 Charges excluding GST *   (w.e.f. 8thJan, 2017 )
UniversityNational Lab/R&D'sIndustryIIT Bombay Users **
Liquid injection/ Headspace 2500/-5000/-12500/-400/-Per Sample
Twister/TDU 3000/-5600/-13500/-400/-Per Sample
Pyrolysis/SPME 5000/-8000/-17000/-400/- Per Sample

* Additional 18% GST will be applicable
**Internal users should directly buy the additional consumables required in modes other than liquid injection and headspace for their own use. In addition, the internal users should support the facility by procuring the consumables needed for running the facility.