Mass spectrometry is an analytical technique that can provide both qualitative (structure) and quantitative (molecular mass or concentration) information on analyte molecules after their conversion to ions. The molecules of interest are first introduced into the ionisation source of the mass spectrometer, where they are first ionised to acquire positive or negative charges. The ions then travel through the mass analyser and arrive at different parts of the detector according to their mass/charge (m/z) ratio. After the ions make contact with the detector, useable signals are generated and recorded by a computer system. The computer displays the signals graphically as a mass spectrum showing the relative abundance of the signals according to their m/z ratio. Liquid chromatography / Mass Spectroscopy (LC / MS) is a technique which combines high performance liquid chromatography HPLC, a powerful analytical separation technique with mass spectroscopy ,a powerful analysis & detection technique. There are two common atmospheric pressure ionization (API) LC/MS process: Electrospray Ionization (ESI) & Atmospheric Pressure Chemical Ionization (APCI). Both are soft ionization technique. Agilent iFunnel technology combines highly efficient electrospray ion generation and focusing of Agilent Jet Stream technology with a hexabore capillary sampling array and dual-stage ion funnel for increased ion sampling and transmission. HPLC combined with mass spectrometer can analysed small molecule as well large molecules like proteins.     -------------------------------------------------------------------------------------------------------------------------------------------------- Specification - Mass Range :50-3200 amu - Mass resolving power: Greater than 45 ,000 FWHM at m/z 2,722 - Mass accuracy – MS mode: Less than 0.8 ppm RMS - Mass accuracy – MS/MS mode: Less than 2 ppm RMS - Mass accuracy temperature stability: Maintain 1 ppm mass accuracy (variations < 3 °C from calibration temperature) - Sensitivity-MS mode (1 pg. Reserpine): 500: 1 RMS - Sensitivity, MS/MS mode (1 pg. Reserpine): 1,500:1 RMS - Direct Infusion for Mass Analysis (MS, MS /MS) - Spectral acquisition rate, MS mode: 50 spectra/second - Spectral acquisition rate, MS/MS mode: 30 MS/MS spectra/second ----------------------------------------------------------------------------------------------------------------- Ionization Method : 1) ESI positive & negative 2) APCI positive & negative Positive to negative switching: 1.5 seconds -------------------------------------------------------------------------------------------------------- Applications - Qualitative Analysis & Quantitative Analysis. - Proteins/Peptides: In-depth qualitative analysis of complex samples. - Intact mass measurement. - Small Molecules: Identification and Characterization. - Metabolite analysis: targeted and non-targeted approaches.