Gas Chromatography: A Mini Review

Abstract

Gas Chromatography (GC or GLC) is a normally utilized analytic technique as a part of numerous research and industrial research facilities for quality control and in addition identification and quantitation of components in a mixture. GC is likewise utilized technique as a part of numerous environmental and forensic labs since it takes into consideration the detection of very little quantities. An expansive variety of tests can be analysed the until the compounds are adequately thermally steady and reasonably volatile. In gas chromatography (GC), the mobile phase is a inert gas (eg helium). The stationary stage is a thin layer of a inert fluid on an inert solid support -, for example, beads of silica pressed into a long thin tube (this adaptable tube is curled ordinarily inside a thermostatically-controlled oven to keep it at a consistent temperature).

Keywords

Gas chromatograph, Autosamplers, Inlets, Detectors, Photo-ionization detector

Gas Chromatography

A gas chromatograph (GC) is an analytical instrument that is utilized to gauge the substance of various segments in a sample [1,2]. The investigation performed by a gas chromatograph is gas chromatography.

Gas chromatography (GC) is a common kind of chromatography used as a piece of analytical science for segregating and investigating exacerbates that can be vaporized without disintegration. Regular employments of GC are trying the immaculateness of a particular substance, or separating of the distinctive segments of a blend [3-6]. In a couple of circumstances, GC may help in recognizing a compound. In preparative chromatography, GC can be used to get ready pure compound from a blend.

Gas chromatography principle: The specimen arrangement is mixed into the instrument enters a gas stream which transports the sample into a division tube known as the "column." (Helium or nitrogen is used as carrier gas.) The distinctive parts are secluded inside the section [7-16]. The identifier measures the measure of the part that leaves the section. To quantify an example with an obscure focus, a standard specimen with known concentration is mixed into the instrument. The standard sample top maintenance time (Retention time) and region are contrasted with the test to ascertain the grouping of the obscure sample.

A gas chromatograph is a Chemical analysis instrument for isolating chemicals in an complex sample mixture. A gas chromatograph utilizes a course through slender tube known as the column, through which distinctive Chemical constituents of a sample go in a gas stream (transporter gas, portable stage) at various rates relying upon their different chemicals and physical properties and their interaction with a particular column filling, called as stationary phase. As the chemicals leave the end of the column, they are detected and analyzed electronically. The capacity of the stationary stage in the column is to isolate various different components, causing on every component to leave the segment at an different time (retention time). Different parameters that can be utilized to change the order or time of retention are the flow rate of carrier gas, length of column and the temperature [17-24].

In a Gas chromatography analysis, a specific known volume of vaporous or fluid analyte is infused into the "entrance" (head) of the column, usually utilizing a microsyringe. As the carrier gas clears the analyte particles through the column, this development is hindered by the adsorption of the analyte atoms either onto the segment depends or onto pressing materials in the segment [25-31]. The rate at which the particles progress along the segment depends on upon the quality of adsorption, which in this manner depends on upon the kind of atom and on the stationary stage materials. Since each sort of particle has an alternate rate of development, the distinctive segments of the analyte mix are separated as they advance along the section and achieve the end of the segment at different times (retention time). An indicator is used to moniter the outlet stream from the segment; in this way, the time at which each part achieves the outlet and the measure of that segment can be resolved. As a rule, substances are recognized by the request in which they rise (elute) from the area and by the retention time of the analyte in the section [32-38].

Physical Components of Gas Chromatography

• Autosamplers

• Inlets

• Detectors

Autosamplers

The autosampler gives the way to bring a sample automatically into the channels. Manual insertion of the sample is possible but no more common. Programmed insertion gives good reproducibility and time-improvement [39-44].

Inlets

The column inlet (or injector) gives the way to bring a sample into a continuous stream of carrier gas. The inlet is a piece of equipment appended to the column head

The common inlet sorts are: S/SL (split/splitless) injector, on- column inlet, PTV injector, and Gas source inlet or gas switching valve, P/T (Purge-and-Trap) system [45].

The decision of carrier gas (portable stage) is very important. The carrier gas must be chemically inert. Generally utilized gasses include nitrogen, helium, argon, and carbon dioxide. The decision of carrier gas is regularly depend upon the sort of indicator which is utilized. The carrier gas framework likewise contains an molecular sieve to expel water and different other impurities. So, helium might be more efficient and give the best separation if flow rates are optimized. Helium is non-combustible and works with a more prominent number of detectors. Thus, helium is the most well-known carrier gas utilized. In any case, the cost of helium has gone up significantly over recent years, causing an expanding number of chromatographers to change to hydrogen gas [16-52].

Detectors

There are numerous detectors which can be utilized as a part of gas chromatography. Distinctive detectors will give different sorts of selectivity [53]. A non- selective detector reacts to all mixes aside from the carrier gas, a particular indicator reacts to a range of compounds with a typical physical or chemical property and a particular detector reacts to a one chemical compound. Detectors can likewise be gathered into concentration dependant detectors and mass flow dependant detectors. The sign from a concentration dependant detector is identified with the grouping of solute in the detector, and does not generally crush the sample Dilution of with make-up gas will bring down the detectors reaction. Mass flow dependant detectors ordinarily decimate the sample, and the sign is identified with the rate at which solute particles enter the detector. The reaction of a mass flow dependant detector is unaffected by make-up gas [54-61].

Various types of detectors used in GC are:

• Mass Spectrometer (GC/MS)

• Flame Ionization Detector (FID)

• Thermal Conductivity Detector (TCD)

• Electron Capture Detector (ECD)

• Nitrogen-phosphorus

• Flame photometric (FPD)

• Photo-ionization (PID)

Mass spectrometer (GC/MS)

Numerous GC instruments are combined with a mass spectrometer, which is a very good blend. The GC isolates the compounds from each other, while the mass spectrometer distinguishes them in view of their fragmentation pattern [62-69].

Flame ionization detector (FID)

This detector is extremely sensitive towards organic atoms (10-12 g/s = 1 pg/s, linear range: 10⁶-10⁷), yet relative insensitive for a couple of small molecules i.e., N₂, NO_x, H₂S, CO, CO₂, H₂O. In the event that appropriate measures of hydrogen/air are blended, the burning does not bear the cost of any or not very many particles bringing about a low background signal. In the event that other carbon containing compounds are introduced with this stream, cations will be created in the profluent stream. The more carbon atoms are in the molecule, the more fragments are framed and the more delicate the dector is for this compound. Unfortunately, there is no relationship between the number of carbon molecules and the size of the signal [70]. Subsequently, the individual reaction components for every compound must be experimentally decided for every instrument. Because of the fact that the sample is burnt (pyrolysis), this procedure is not appropriate for preparative GC. Furthermore, a few gasses are typically required to work a FID: hydrogen, oxygen (or commpressed air), and a carrier gas [71-73].

thermal conductivity detector

Thermal Conductivity Detector is less sensitive than the FID (10^-5-10^-6 g/s, straight range: 10³-10⁴), yet is fitting for preparative applications, in light of the way that the example is not annihilated. The acknowledgment relies on upon the relationship between the two gas streams, one containing only the carrier gas, the other one containing the transporter gas and the compound. Really, a carrier gas with a high warm conductivity i.e., helium or hydrogen is used to amplify the temperature distinction (and along these lines the distinction in resistance) between two fibers (=thin tungsten wires). The broad surface-to-mass extent permits a fast equilibration to a relentless state. The temperature distinction between the reference and the specimen cell fibers is seen by a Wheatstone bridge circuit [74-85].

electron capture detector (ECD)

This detector comprises of a depression that contains two terminals and a radiation source that transmits - radiation (i.e., 63Ni, 3H). The impact amongst electrons and the carrier gas (methane in addition to an inert gas) creates a plasma-containing electrons and positive ions. On the off chance that a compound is available that contains electronegative molecules, those electrons will be "caught" to frame negative particles and the rate of electron accumulation will diminish [86]. The identifier is to a great degree particular for mixes with particles of high electron liking (10-14 g/s), yet has a generally little straight range (~10²-10³). This indicator is every now and again utilized as a part of the investigation of chlorinated mixes i.e., pesticides (herbicides, insecticides), polychlorinated biphenyls, and so forth for which it shows a high sensitivity [87,88].

Nitrogen-phosphorus

A type of thermionic detector where nitrogen and phosphorus change the work capacity on an uncommonly coated bead and a subsequent current is measured.Alkali Flame Detector, AFD or Alkali Flame Ionization Detector, AFID. AFD has high affectability to nitrogen and phosphorus, like NPD. Nonetheless, the alkaline metal particles are supplied with the hydrogen gas, instead of a bead over the fire. Consequently AFD does not endure the "fatigue" of he NPD, but rather gives a steady sensitivity over drawn out stretch of time. What's more, when alkaline ions are not added to the fire, AFD works like a standard FID [89-92].

Flame photometric (FPD)

Flame photometric (FPD) which utilizes a photomultiplier tube to identify spectral lines of the mixes as they are burned in a fire. Compounds eluting off the column are conveyed into a hydrogen energized fire which excites particular components in the molecule, and the excited components (P,S, Halogens, Some Metals) radiate light of particular characteristic wavelengths. The emitted light is separated and detected by a photomultiplier tube. Specifically, phosphorus emission is around 510-536 nm and sulfur discharge os at 394 nm [93,94].

Photo-ionization detector (PID)

The Polyarc reactor is an additional to new or existing GC-FID instruments that progressions over each natural compound to methane atoms going before their recognition by the FID [95-100]. This framework can be used to upgrade the reaction of the FID and think about the recognition of various more carbon-containing mixes. The complete change of mixes to methane and the now indistinguishable reaction in the indicator moreover it additionally disposes of the prerequisite for alignments and gauges since response variables are all equivalent to those of methane. This checks the fast examination of complex blends that contain atoms where standards are not open. The successive reactor is sold economically as the Polyarc reactor, available online from the Activated Research Company.

Conclusion

Gas chromatography (GC) is a common kind of chromatography used as a piece of analytical science for segregating and investigating exacerbates that can be vaporized without disintegration. Various types of detectors are used for analysis of the product based on the retention time. An expansive variety of tests can be analysed the until the compounds are adequately thermally steady and reasonably volatile.

References

1. Mahendra Kumar T, et al. Evaluation of the isotopic abundance ratio in biofield energy treated resorcinol using gas chromatography-mass spectrometry technique. Pharm Anal Acta. 2016;7: 481.
2. Arnoldi S, et al. Validation study of analysis of 1-phenyl-2-propanone in illicit methamphetamine samples by dynamic headspace gas chromatography mass spectrometry. J Chromatogr Sep Tech. 2016;7:322.
3. Nimmanwudipong T, et al. Determination of intramolecular 13c isotope distribution of pyruvate by headspace solid phase microextraction-gas chromatography-pyrolysis-gas chromatography-combustion- isotope ratio mass spectrometry (HS-SPMEGC-Py-GC-C-IRMS) Method. J Anal Bioanal Tech. 2015;7:293.
4. hen Z, et al. Utilization of a matrix effect to enhance the sensitivity of residual solvents in static headspace gas chromatography. J Chromatogr Sep Tech. 2015;6:289.
5. okhart M, et al. Determination of organochlorine pesticides in wildlife liver and serum using gas chromatography tandem quadrupole mass spectrometry. J Chromatogr Sep Tech. 2015;6:286.
6. Albert K, et al. (2015) Investigating insect adhesion secretions by gas chromatography-mass spectrometry. J Chromatograph Separat Techniq. 2015;S6:001.
7. Bargańska Ż, et al. Development of a gas chromatography - tandem mass spectrometry procedure for determination of pesticide residues in honey and honeybee samples. J Chromatograph Separat Techniq. 2015;S6:002.
8. Trivedi MK, et al. Investigation of isotopic abundance ratio of biofield treated phenol derivatives using gas chromatography-mass spectrometry. J Chromatograph Separat Techniq. 2015;S6:003.
9. Trivedi MK, et al. Isotopic abundance analysis of biofield treated benzene, toluene and p-xylene using gas chromatography-mass spectrometry (GC-MS). Mass Spectrom Open Access. 2015;1:102.
10. EL-Maali NABO and Wahman AY. Gas chromatography-mass spectrometric method for simultaneous separation and determination of several pops with health hazards effects. Mod Chem appl. 2015;3:167.
11. Steiner WE and English WA. Emerging trends in gas chromatography and mass spectrometry instrumentation for analytical & bioanalytical techniques. J Anal Bioanal Tech. 2015;6:e118.
12. Wu PS, et al. Gas chromatography- mass spectrometry analysis of photosensitive characteristics in citrus and herb essential oils. J Chromatogr Sep Tech. 2015;6:261.
13. Eiceman GA, et al. Volatile organic compounds in headspace over electrical components at 75 to 200°c part 2. analytical response with gas chromatography-differential mobility spectrometry for airborne vapor monitoring. J Environ Anal Chem. 2014;1:116.
14. Rodrigues LF, Goudinho FS, Laroque DO, Lourega LV, Heemann R, et al. (2014) An alternative gas chromatography setting for geochemical analysis. J Chem Eng Process Technol. 2014;5:208.
15. Gnana Raja M, Geetha G, Sankaranarayanan A (2014) A concise study of organic volatile impurities in ten different marketed formulations by [gc/hs-fid/ms] gas chromatography technique. J Anal Bioanal Tech. 2014;5:202.
16. Ruan ED, Aalhus J, Juarez M (2014) Sensitive analysis of off-flavor compounds, geosmin and 2-methylisoborneol, in water and farmed sturgeon by using stir bar sorptive extraction coupled with thermal desorption and gas chromatography-mass spectrometry. J Chromatograph Separat Techniq. 2014;5:228.
17. Townsend KP and Pratico D. Novel therapeutic opportunities for Alzheimer’s disease: focus on nonsteroidal anti-inflammatory drugs.The FASEB J.2005;19:1592-1601.
18. Gong ZY, et al. A ringdown breath acetone analyzer: performance and validation using gas chromatography- mass spectrometry. J Anal Bioanal Tech. 2014;S7:013.
19. Monteiro J, et al. Simultaneous quantification of propofol and its non-conjugated metabolites in several biological matrices using gas chromatography/ion trap – mass spectrometry method. J Anal Bioanal Tech. 2014;5: 195.
20. Karthikeyan R, et al. Volatile elements of coconut toddy (cocos nucifera) by gas chromatography–mass spectrometry. J Chromatograph Separat Techniq. 2014;5:213.
21. Sampson L, et al.Gas chromatography-mass spectrometric analysis of forensic drug flunitrazepam upon exposure to uv irradiation. J Forensic Res. 2013;4:193.
22. Fatemi MH, et al. Chemometrics optimization of volatile organic compounds analysis in water by static headspace gas chromatography mass spectrometry. Hydrol Current Res. 2013;4:153.
23. Deshpande S, et al. Microbial conversion of plant based polyunsaturated fatty acid (pufa) to long chain pufa and its identification by gas chromatography. J Biotechnol Biomaterial. 2013;S13: 006.
24. Manickuma T and John W Dehydration of 2-methylisoborneol to 2-methyl-2-bornene in the trace analysis of taste-odorants in water by purgeand- trap sampling with gas chromatography (GC) -mass selective (MS) detection. Hydrol Current Res. 2012;3:127.
25. Motladiile S, et al. Development and validation of a gas chromatography-mass spectrometry method for the determination of pcbs in transformer oil samples-application on real samples from botswana. J Chromatograph Separat Techniq. 2012;2:116.
26. Yacob AR, et al. Detection of vapour metabolites of glue sniffer's urine using head space gas chromatography mass spectrometry. J Drug Metab Toxicol. 2011;2:112.
27. Chen JL, et al. Urinary metabolomic analysis of human gastric cancer mouse models and patients using gas chromatography/mass spectrometry. J Mol Biomark Diagn. 2011;S2:003.
28. Ekeberg D, et al. Identification of brominated flame retardants in sediment and soil by cyclohexane extraction and gas chromatography mass spectrometry. J Chromatograph Separat Techniq. 2010;1:102.
29. Sheng ZY, et al. The study of analytical identification on main monomer compounds of spoiled grass carp by high performance liquid chromatography of quadrupole time of flight mass spectrometry. J Food Process Technol. 2016;7:600.
30. Piteni AI, et al. HILIC chromatography – an insight on the retention mechanism. J Chromatogr Sep Tech. 2016;7:326.
31. Eyathilakan N, et al. Anion exchange chromatography for purification of antigen b of cystic echinococcosis. J Chromatogr Sep Tech. 2014;5:254.
32. Saran S, et al. Development of a highly sensitive, fast and efficient screening technique for the detection of 2,3-butanediol by thin layer chromatography. J Chromatogr Sep Tech. 2014;5:251.
33. Wakamoto H, et al. Development of a new dermatophyte-detection device using immunochromatography. J Med Diagn Meth. 2016;5:216.
34. Ezhilarasi K, et al. A simple and specific method for estimation of lipoic acid in human plasma by high performance liquid chromatography. J Chromatogr Sep Tech. 2014;5:245.
35. Michalski R.Ion chromatography and related techniques 2016. J Chromatogr Sep Tech. 2016;7: 325.
36. Tabbabi K and Karmous T.Characterization and identification of the components extracted from 28 lichens in tunisia by high performance thin-layer chromatography (HPTLC), morphologic determination of the species and study of the antibiotic effects of usnic acid. Med Aromat Plants. 2016;5:253.
37. Shashkov MV and Sidelnikov VN. Separation of phenol-containing pyrolysis products using comprehensive two-dimensional chromatography with columns based on pyridinium ionic liquids. J Anal Bioanal Tech. 2016;7:313.
38. Akan JC, et al. Determination of organochlorine, organophosphorus and pyrethroid pesticide residues in water and sediment samples by high performance liquid chromatography (HPLC) with uv/visible detector. J Anal Bioanal Tech. 2014;5:226.
39. Ivkovic B, et al. Chemometrical evaluation of metoprolol tartarate enantiomers separation applying conventional achiral chromatography. J Anal Bioanal Tech. 2016;7:303.
40. Nouha K, et al. Fourier transform infrared spectroscopy and liquid chromatography–mass spectrometry study of extracellular polymer substances produced on secondary sludge fortified with crude glycerol. J Material Sci Eng. 2016;5:240.
41. Caldwell GW and Lang W. Profiling rat brain monoacylglycerol lipase activity using an ammonia-adduct enhanced selected ion monitoring liquid-chromatography positive electrospray ionization mass spectrometry assay. Pharm Anal Acta. 2016;7:470.
42. Kuvshinova SA, et al. Selectivity, Thermodynamic and anisotropic properties of substituted liquid-crystal cyanoazoxybenzenes as stationary phases for gas chromatography. J Chromatogr Sep Tech. 2016;7:314.
43. Mahabaleshwara K, et al. Phytochemical investigations of methanol leaf extracts of randia spinosa using column chromatography, HPTLC and GC-MS. Nat Prod Chem Res. 2016;4:202.
44. Musirike MR, et al. Stability indicating reverse phase chromatographic method for estimation of related substances in voriconazole drug substance by ultra performance liquid chromatography. Pharm Anal Acta. 2016;7:460.
45. Rodriguez A, et al. Development and validation of a liquid chromatography method with electrochemical detection for hydroxyurea quantification in human plasma and aqueous solutions. J Chromatogr Sep Tech. 2014;5:244.
46. Nakano T and Ozimek L. Selective removal of phenylalanine impurities from commercial κ-casein glycomacropeptide by anion exchange chromatography. J Food Process Technol. 2015;7:537.
47. Gritti F (2015) Retention mechanism in hydrophilic interaction liquid chromatography new insights revealed from the combination of chromatographic and molecular dynamics data. J Chromatogr Sep Tech. 2015;6:309.
48. Guo WR, et al. Simultaneous detection method for mycotoxins and their metabolites in animal urine by using impurity adsorption purification followed by liquid chromatography-tandem mass detection. J Chromatogr Sep Tech. 2015;6:308.
49. Linnerz K, et al. Liquid chromatography-tandem mass spectrometry method for the quantification of fentanyl and its major metabolite norfentanyl in critically ill neonates. J Chromatograph Separat Techniq. 2015;S6:004.
50. Mulubwa M, et al. Development and validation of high performance liquid chromatography tandem mass spectrometry (hplc-ms/ms) method for determination of tenofovir in small volumes of human plasma. J Chromatogr Sep Tech. 2015;6:300.
51. Gineys M, et al.Simultaneous determination of pharmaceutical and pesticides compounds by reversed phase high pressure liquid chromatography. J Chromatogr Sep Tech. 2015;6:299.
52. Justiz-Vaillant AA, et al. Purification of the mule (equus mulus) igg by protein a - affinity chromatography. J Chromatogr Sep Tech. 2015;6:298.
53. Goswami J.Different separation or experimental techniques for clinical chromatography: small review. J Chromatogr Sep Tech. 2015;6:297.
54. Chauhan MK, Bhatt N. A simple and modified method development of vancomycin using high performance liquid chromatography. J Chromatogr Sep Tech. 2015;6:296.
55. Amini A. Identification of ɛ-caprolactam and melamine in polyvinyl-pyrrolidone powder by double injection micellar elektrokinetic chromatography.Pharm Anal Acta. 2015;6:442.
56. Wang JM, et al. Analysis of fructose 1,6-diphosphate in fermentation broth using ion chromatography. Biochem Anal Biochem. 2015;4:209.
57. Salvatierra-Stamp VC, et al. Supercritical-fluid chromatography with diode-array detection for emerging contaminants determination in water samples. method validation and estimation of the uncertainty. J Chromatogr Sep Tech. 2015;6:291.
58. Belissa E, et al. Liquid chromatography–tandem mass spectrometry for simultaneous determination of ticarcillin and vancomycin in presence of degradation products.application to the chemical stability monitoring of ticarcillin-vancomycin solutions.J Chromatogr Sep Tech. 2014;5:243.
59. Willmann L, et al. Comprehensive Two-Dimensional Liquid Chromatography in Metabolome Analysis. J Chromatogr Sep Tech. 2015;6:288.
60. Bel EC, et al. Fluorometric determination of vitamin constituents in human plasma using ultra performance liquid chromatography. J Chromat Separation Techniq. 2012;3:143.
61. Gupta A, et al. Determination of quercetin a biomarker in hepatoprotective polyherbal formulation through high performance thin layer chromatography. J Chromatogr Sep Tech. 2015;6:285.
62. Trivedi DK, et al. Development of zwitterionic hydrophilic liquid chromatography (zic®hilic-ms) metabolomics method for shotgun analysis of human urine. J Chromat Separation Techniq. 2012;3:144.
63. Guerrero-German P, et al. simulation of frontal protein affinity chromatography using MATLAB. J Chem Eng Process Technol. 2012;3:138.
64. Shao C, et al. Quantification of acyclovir in human plasma by ultra-high-performance liquid chromatography - heated electrospray ionization - tandem mass spectrometry for bioequivalence evaluation. J Anal Bioanal Tech. 2012;3:139.
65. Chakravarti B and Chakravarti DN.Liquid chromatography - tandem mass spectrometry - application for clinical chemistry laboratory. J Mol BiomarkDiagn. 2015;6:244.
66. Steiner WE and English WA. Emerging trends in liquid chromatography and mass spectrometry instrumentation for analytical & bioanalytical techniques. J Anal Bioanal Tech. 2012;3:e106.
67. Stephen S, et al. Tracking interfacial adsorption/desorption phenomena in polypropylene/biofuel media using trace cr3+/cr6+ and as3+/as5+-a study by liquid chromatography-plasma mass spectrometry. J Pet Environ Biotechnol. 2015;6:239.
68. Belico de et al. Gel filtration chromatography technique as tool of simple study seminal plasma proteins in domestic animals. J Chromatogr Sep Tech. 2015;6:281.
69. Sanaki T, et al. Improvements in the high-performance liquid chromatography and extraction conditions for the analysis of oxidized fatty acids using a mixed-mode spin column. Mod Chem appl. 2015;3:161.
70. Delhiraj N and Anbazhagan S. A simple, isocratic and ultra-fast liquid chromatography / mass spectrometry method for the estimation of barnidipine in human plasma. Pharm Anal Acta. 2015;6:400.
71. Amagai T, et al. Determination of nicotine exposure using passive sampler and high performance liquid chromatography. Pharm Anal Acta. 2015;6:399.
72. Guzel M, et al. Estimation of octanol- water partition coefficient using cationic gemini surfactants by micellar electrokinetic chromatography. J Chromatogr Sep Tech. 2015;6:275.
73. Santini DA, et al. Development of a high performance liquid chromatography method for the determination of tedizolid in human plasma, human serum, saline and mouse plasma. J Chromatogr Sep Tech. 2015;6:270.
74. Lin G, et al. Determination of sodium tanshinone iia sulfonate in rat plasma by high performance liquid chromatography and its application to pharmacokinetics studies. Pharm Anal Acta. 2015;6: 383.
75. Ulmer CZ, et al. Liquid chromatography-mass spectrometry metabolic and lipidomic sample preparation workflow for suspension-cultured mammalian cells using jurkat t lymphocyte cells. J Proteomics Bioinform. 2015;8:126-132.
76. Karl WKS, et al. A Pharmacokinetic analyses of ferulic acid in rat plasma by liquid chromatography– tandem mass spectrometry: a synergistic action of an ancient herbal decoction fo shou san. Pharm Anal Acta. 2015;6:361.
77. Maher HM (2015) Stacking as sample on-line pre-concentration technique in microemulsion electrokinetic chromatography. J Chromatogr Sep Tech. 2015;6:e130.
78. Virkar PS, et al. Development and validation of a high performance liquid chromatography method for determination of telmisartan in rabbit plasma and its application to a pharmacokinetic study. J Anal Bioanal Tech. 2012;3:133.
79. MajidanoAS and Khuhawar MY. GC analysis of amino acids using trifluoroacetylacetone and ethyl chloroformate as derivatizing reagents in skin samples of psoriatic and arsenicosis patients. Chromatographia. 2011;73:701-708.
80. Awan MA, et al. Determination of biogenic diamines with a vaporisationderivatisation approach using solid-phase microextraction gas chromatography-mass spectrometry. Food Chemistry.2008; 111:462-468.
81. Zahradnícková H, et al. Gas chromatographic analysis of amino acid enantiomers in Carbetocin peptide hydrolysates after fast derivatization with pentafluoropropylchloroformate. Amino Acids.2008;35: 445-450.
82. Bliesner DM. Validating Chromatographic methods: a practical guide. John Wiley and Sons. 2006.
83. Amirav A, et al. Gas chromatography-mass spectrometry with supersonic molecular beams. J Mass Spectrom. 2008;43:141-163.
84. Chauhan A, et al.GC-MS technique and its analytical applications in science and technology. J Anal Bioanal Tech. 2014;5:222.
85. Handley AJ and Adlard ER. Gas chromatographic techniques and applications. Sheffield Academic, London.2001.
86. Kitson FG and Larsen BS, McEwen CN. Gas chromatography and mass spectrometry: a practical guide. Academic Press, Boston.1996.
87. Maurer HH, et al. Mass spectral and gc data of drugs, poisons, pesticides, pollutants and their metabolites. Weinheim: Wiley-VCH. 2007.
88. Reade S, et al. Optimisation of sample preparation for direct spme-gc-ms analysis of murine and human faecal volatile organic compounds for metabolomic studies. J Anal Bioanal Tech.2014;5:184.
89. Pesce A, et al. Medication and illicit substance use analyzed using liquid chromatography tandem mass spectrometry (LC-MS/MS) in a pain population. J Anal Bioanal Tech. 2012;3:135.
90. Justiz Vaillant AA, et al. Purification of Immunoglobulin Y (IgY) from the Ostrich (Struthio camelus) by Staphylococcal Protein a (Spa) Affinity Chromatography. J Chromat Separation Techniq. 2012;3:127.
91. Caciotta M, et al. Orthonormal gas-chromatography sets of extra virgin olive oil. J Nutr Food Sci. 2014;4:317.
92. Gugulothu DB, et al. A versatile high performance liquid chromatography method for simultaneous determination of three curcuminoids in pharmaceutical dosage forms. Pharmaceut Anal Acta. 2012;3:156.
93. Kandasamy K, et al. Bioanalytical method development, validation and quantification of metaxalone in rat plasma by liquid chromatography tandem mass spectrometry. J Bioanal Biomed. 2012;S6:006.
94. Gong X, et al. Determination of 15 mycotoxins in foods and feeds using high performance liquid chromatography- tandem mass spectrometry with gel permeation chromatography combined quechers purification. J Chromat Separation Techniq. 2012;3:125.
95. Taylor CM, et al. An arson investigation by using comprehensive two-dimensional gas chromatography- quadrupole mass spectrometry. J Forensic Res. 2012;3:169.
96. Manickum T and John W. Method validation for the trace analysis of geosmin and 2-methylisoborneol in water by A Salt-Free Apurge-and-trap sampling/GC-MS, using the eclipse 4660 sample concentrator. Hydrol Current Res. 2012;3:134.
97. Alvi SN, Yusuf A and Hammami MM. Simultaneous quantification of vitamin d-2, vitamin d-3, and their 25- hydroxy metabolites in human plasma by high performance liquid chromatography. J Bioequiv Availab. 2012;S14:007.
98. Duan Y, et al. On-line solid-phase extraction based on poly (NIPAAm-MAA-co-EDMA) monolith coupled with high-performance liquid chromatography for determination of nitrendipine and nisoldipine in human urine. J Chromat Separation Techniq. 2012;3:123.
99. Chaitanya Krishna A, et al. Determination of Pyrazinamide in Human Plasma Samples Containing Fixed Dose Combination Molecules by using Liquid Chromatography Tandem Mass Spectrometry. Adv Pharmacoepidem Drug Safety. 2012;1:108.
100. Manickum T, et al. Trace analysis of taste-odor compounds in water by "salt-free" purge-and-trap sampling with gc-ms detection. Hydrol Current Res. 2011;2:121.