PHARMACEUTICAL APPLICATIONS OF GAS CHROMATOGRAPHY(GC), PHARMACEUTICAL ANALYSIS BY P.RAVISANKAR.
PHARMACEUTICAL APPLICATIONS OF GAS CHROMATOGRAPHY (GC)prof. RavisankarVignan Pharmacy collegeValdlamudiGuntur Dist.Andhra PradeshIndia.firstname.lastname@example.org
High speed: analysis in a matter ofminutes and routine drugs analysis of fewdrugs In a matter of few seconds also possible.High sensitivity we see both rapid analysis aswell as high sensitivity.For ex is a 2 1/2 min of separation threecommon pesticides ,Methyl parathion,Malathion,Ethion at pg levels. Pg means 10-12 gramsthese areparts per billion. This is very goodexample of both the high speed as well as avery sensitive detection.Applications of gas chromatography:Gas chromatography (GC) is an instrumental technique used forensically in drug analysis,arson, toxicology, and the analyses of other organic compounds.The GC is one of popular instrument used in the world Several (applications)advantagesinclude.
2.High resolution: Many compounds can be resolved nicely.For ex: gasoline has been resolved in to over 300different peaks complexsample of Petroleum.Oil refinery – separates fractions of oil forpetroleum products.
Gas chromatography – mass spectrometry (GC/MS) is a well established method foranalysis of ignitable liquids.According to the US Fire Administration, arson is the leading cause of fires and thesecond leading cause of deaths and injures, and that’s why arson investigation is offorensic significance for the criminal justice system.Commercially available fuels or solvents that are mixtures consisting of hundreds ofcomponents are typically used to start a fire. Analysis becomes very difficult becauseignitable liquids consist of same or similar components at different concentrations, inaddition, fire may evaporate some of the components and thus altering the compositionof residual ignitable liquids found in fire debris.Analysis, detection, and identification of accelerants inarson studies are indeed applicable in gaschromatography.Novel applications in Gas chromatography:Arson studies:Detection of Arson Accelerants Using gas chromatography:
For trace evidence, the ability to get the most information from the smallest sample provided, while preserving the maximumamount for other tests, is critical in delivering results to solve crimes.Gas chromatography mass spectrometry (GC/MS) is an important technique in thedetection and identification of both bulk drugs and trace level drugs in biologicalsamples. The PerkinElmer® Clarus® 600 GC/MS is a highly-sensitive and robust systemwith flexibility to accommodate the wide range of analyses typical to drug investigations.Drugs-of-Abuse Analysis by GC/MS
Determination of Pesticides, Residue in Aquaculture ProductsDetection and Quantitation by Gas ChromatographyAgricultural chemicals such as fertilizers and pesticides have made an importantcontribution to agriculture. Pesticides protect crops from pests and diseases.They have brought about large yield increases. since almost all chemicals that cankill pests are also potentially damaging to human health. Legislation requires thatpesticide use is appropriately controlled and maximum residue levels (MRLs) notbe exceeded.Detection method is the process of identifying the pesticides anddetermining their concentrations. With the aid of an analyticalinstrument, such as a gas chromatograph (GC), we can obtaininformation about the original sample by running a standardsolution containing the pesticide(s) at a known concentration andcomparing it with the sample.
Description(±)-MephobarbitalHexobarbitalcarrier gas: helium, 20 cm/sec @ 275 °Ccolumn: β-DEX 120, 30 m × 0.25mm I.D., 0.25 μm.det.: FID, 300 °Cinjection: 100:1 splitoven: 210 °COne enantiomer in the mixture may have an activity or toxicity ... Out of themany chiral complexing agents used to separate chiral drugs by gaschromatography (GC).Barbiturate Enantiomersapplication for GC:
Analysis ofAnticonvulsants by GC-FID using an HP-1column. Source:Agilent Technologies.
Blood alcohols (packed application GC)The determination (accurately measure)of blood alcohol content (BAC) is one of the mostcommon tests performed by forensic laboratories.Blood alcohol analysis is used by law enforcement to determine if a driver was unlawfullyoperating a vehicle. The results will be used in a court of law, therefore it is important tominimize systematic and operator errors.This application note presents the details of an optimized column separation method forthe determination of ethyl alcohol, the internal standard npropyl alcohol, three othercommon alcohols, and many potentially interfering common volatiles present in samplesbeing analysed for measures of driving under the influence of alcohol" (DUI )acronym usedin many regulating districts)This possible method for determining forensic blood alcohol concentrations.carrier gas: helium, 20 mL/min.column: 6 ft. × 2 mm I.D. glassdet.: FIDinjection: 1 μLoven: 85 °Cpacking: 5% Carbowax 20M on 60/80 Carbopack Bdetermination of alcohol (i.e. ethanol) in blood or urine. One obvious application is whenlaw enforcement agencies need to determine whether or not someone is inebriated. Inthese cases, high sensitivity is required since 0.1% blood alcohol content is considered to belegally intoxicated in most states.
Analysis of p-Xylene by GC-FID using a HP-INNOWax columnThe purity of solutions, from relatively puresolvent such as xylene, to liquors such asscotch can be also be determined by GC. Twoexamples are shown below.Analysis of Minor Components of Scotch byGC-FID using a HP-101 Column
Analysis of Alkaloids and Barbiturates byGC-FID with an Ultra 2 column..
GC can also be used todetermine the identity of naturalproducts containing complexmixtures of similar compounds.For example, the geographicsource of crude oil or natural gascan be determined by the“fingerprint”, or relativedistribution of major and tracecompounds in each oil. Naturalproduce oils, such as foodproducts or fragrances, can beidentified by GC-FID or GC-MS. Afew examples of the separationof these complex mixtures areshown below.
Common Applications:Quantification of pollutants in drinking and wastewaterusing official U.S. Environmental Protection Agency (EPA)methodsQuantification of drugs and their metabolites in blood andurine for both pharmacological and forensic applicationsIdentification of unknown organic compounds in hazardouswaste dumpsIdentification of reaction productsAnalysis of industrial products for quality controlANALYSIS OF VOLATILE ORGANIC COMPOUNDS IN INDOOR AIR
Gas chromatography is a physical separation method in where volatile mixtures areseparated. It can be used in many different fields such as pharmaceuticals,cosmetics and even environmental toxins. Since the samples have to be volatile,human breathe, blood, saliva and other secretions containing large amounts oforganic volatiles can be easily analyzed using GC. Knowing the amount of whichcompound is in a given sample gives a huge advantage in studying the effects ofhuman health and of the environment as well.Air samples can be analyzed using GC. Most of the time, air quality control units useGC coupled with FID in order to determine the components of a given air sample.Although other detectors are useful as well, FID is the most appropriate because ofits sensitivity and resolution and also because it can detect very small molecules aswell.GC/MS is also another useful method which can determine the components of agiven mixture using the retention times and the abundance of the samples. Thismethod be applied to many pharmaceutical applications such as identifying theamount of chemicals in drugs. Moreover, cosmetic manufacturers also use thismethod to effectively measure how much of each chemical is used for theirproducts.
GC and liquid chromatography together just been the primiar techinique for Trace analysis oforganic and inorganic compounds. If I think all the work which is been done in Air polutionand water polutionand food saftery we hv. To analyze pestisides toxic chemicals founds inFood and food productswe have to analyze the pestiside and food safty and toxic chemicals and foodPorductis and all of these things are daily and rapidly by gc and or liquid chromatographjy.
Primary column: Fused silica,30m by.25 mm ID.5%diphenyl95%dimethyl polysiloxone stationary phase having 0.25 micrometer film thickness.Secondary column:Fused silica,30m by 0.25mm ID internally coated with a14%cyanopropyl phenyl and 86% dimethyl polysiloxone stationary phase having .25 µmFilm thickness.The role of modulator is to collect fractions form chromatographic technique.It employs 2 columns in series separated by a modulator.The role of modulator is to collect the fractions from first column( often called asFirst dimention column or primary column or 1o column and focus then on to theThen on to the secondary column or 20 column.Primany columns tend to be 30m x .25 mm ID.Secondary columns tend to be 1-2 m X 0.10mm ID are common for secondary columns.
Gas Chromatographic ConditionsGas chromatograph Model: Shimadzu GC-17A, equipped with 63Nielectron capturedetector, attached to a CBM-102 Chromatopak recorder systemDetector: Electron capture detector (ECD)Column: SPB-608 (Supelco), Capillary (Fused silica), 30m x 0.25mm I. D., 0.25 umfilmColumn Oven Temperature: 150o C (4 min) to 290o C at 8o C/min, hold 10 min.Detector temperature: 300o CInjector temperature: 220 o CCarrier gas: Nitrogen (N2) at f low rate of 40 cm/sec.Measure the area or height of residue peak(s) and determine the residue amountby comparison to peak area or height obtained from a known amount ofappropriate reference material(s).
determination of the VOCs toluene , ethylbenzene ,o-xylene and cumene (TEXC) in air analysed and quantified using a gas chromatographwith flame ionisation detection (GC-FID).Volatile organic compounds (VOCs) are a cause of concern for human healthdue to their increased presence in the indoor environment.They are responsible for a phenomenon known as the sick building syndrome (SBS).Air monitoring is being used to assess indoor pollution.
In most forensic applications of GC, a sample is prepared by dissolving it in a solvent, and thesolution is injected into the instrument using a syringe. For example, to analyze a whitepowder suspected of being cocaine, a small portion is weighed out and dissolved in a solventsuch as methylene chloride, methanol, or chloroform. A tiny portion of the sample is thendrawn up into a syringe and injected into the heated injector port of the instrument. Themobile phase gas (called the carrier gas) also enters the injector port, picking up thevolatilized sample and introducing it into the column where the separation process occurs. Ifthe sample contains cocaine, it will emerge from the column at a given time (known as theretention time) that can be compared to the retention time of a known standard sample ofcocaine. The retention time in conjunction with information obtained from the detector isused to positively identify the compound as cocaine if indeed it is present. Another methodof sample introduction for GC is called pyrolysis, in which a solid sample such as a fiber orpaint chip is heated in a special sample holder to extreme temperatures, causing the sampleto decompose into gaseous components that can then be introduced into the GC. Pyrolysis isused when the sample is not readily soluble in common GC solvents.The pharmaceutical industry also heavily usesGC and HPLC to determine the purity ofreagents, the identity of synthesis products,and the identity of medicines and illicit drugs.A few examples are shown below
GC-MS used in thyroid cancer studyGas chromatography-mass spectrometry (GC-MS) has been used toinvestigate the pathogenic differences in a form of cancer according togender and menopausal condition.In a study published by BMC(biomed central services publish originalresearch on oncology)) Cancer, scientists sought to evaluate themetabolic changes in urinary steroids in men and pre- and post-menopausal women with papillary thyroid carcinoma (PTC).GC-MS was used to measure the urinary concentrations of 84 steroids inall of the patients against corresponding controls.The metabolic ratio of 2-hydroxy estrone to 2-hydroxy-17 beta-estradiolin particular showed gender differences in PTC patients.It is hoped the findings could help better understand the pathogenicdifferences in PTC according to gender and menopausal conditions.
Separation of m- and p- Xylenes by GasChromatography on DimethylPolysiloxaneshort piece of 5% diphenyl 95%dimethyl column connected to awax column.Cryofocusing was done on the 5(which still has some diffusivity at -80°C) and rapid heating to 40°Crestored the wax to a “liquid” toallow the efficient separation of m-and p-xylenes. A wax is one of theonly commercially-available capillaryGC stationary phases that willseparate m- and p- xylenes.
. One advantages of adsorption( GC) chromatography, as is also true for GSC, is that it isable to retain and separate some compounds that can not be separated by othermethods. One such application is in the separation of geometrical isomers.
Barbiturates are a class of compounds that are central nervous system depressants. They arecategorized as sedatives or hypnotics and are primarily used in the treatment of anxiety,insomnia, and convulsive disorders. Barbiturates can be analyzed in eithertheir underivatized or derivatized forms by gas chromatography. Derivatizationof the barbiturates is most commonly performed by methylation of the amidonitrogens in positions 1 and 3. Methylating reagents like tetramethylammoniumhydroxide (TMAH) and trimethylanilinium anilinium hydroxide (TMPAH) can be used.Analysis of barbiturates can also be performed on underivatized compounds.However, underivatized barbiturates have a tendency to produce overloadedor tailing peaks. Maintain injection port liners, guard columns, and analyticalcolumns regularly to achieve good peak shape and adequate resolution.
Chlordiazepoxide is a long acting benzodiazepine drug. The half-life of Chlordiazepoxide is 5– 30 hours but has an active benzodiazepine metabolite (desmethyldiazepam) which has ahalf-life of 36 – 200 hours.A rapid gas chromatographic method for the determination of diazepam and metabolites inbody fluids . A rapid method is described for the extraction of diazepam and its metabolitesfrom plasma and urine. The procedure is applicable to subsequent analysis by electroncapture gas chromatography, and has been used for the analysis of clinical samples. Thedetection limit for diazepam is about 0.01 μg/ml,
Rapid Method for Determination of Ethanol in AlcoholicBeverages Using Capillary Gas ChromatographyEthanol content is very important for the mouth-feeland flavor of alcoholic beverages. Ethanol contents ofwine, liqueur, and beer range from 7~21%(v/v),20~50%(v/v), and 3~6%(v/v), respectively(1). In general,ethanol contents serve as the quality index and taxationfactor for alcoholic beverages(2). After entering WTO,alcoholic beverages in Taiwan are taxed according to theethanol contents, like the taxation system in UnitedStates(3). The higher the ethanol content in an alcoholicbeverage, the higher the tax.it takes only 7~8 min to complete asample analysis for the determination of ethanol content ina beverage sample. A sample solution (0.5 mL) is mixedwith adequate amount (5 mL) of 1% (w/v) internal standardsolution (acetonitrile, equivalent to 50 mg), and injectedinto a capillary GC.
Breath Alchohol TestingDrunk driving costs countless lives and destroys families around the world each year. Inmost countries drunk driving is illegal and in pursuing these laws the police utilizesbreathalyzer tests.Test equipment must be perfectly calibrated to stand up in a court of law. Therefore oneof the calibration methods is to use a calibration gas. The demands on such a calibrationgas are strict, it must be easy to use, be stable, portable and fool-proof. Linde producesand delivers such calibration gases with the Breathcal program.Determination of free cholesterol in milk fat:rapid and direct gas chromatographic (GC) method for determining free cholesterol inmilk fat using a capillary column and programmed-temperature vaporizerinjector wasassayed.Soil and Water MeasurementContamination of soil and water can come from many areas, including acid rain,pesticides industrial waste, landfill, and raw sewage. Analytical procedures includeGC/MS.
Environmental measurement is accomplished in many ways. Air samples may becollected using sample bags or containers and analysed using gas chromatography.For example, with the US EPA CEMS have a requirement under some environmentalregulations for either continuous compliance determination of the level in which thefacility is out of compliance with acceptable emission standards.In all areas, a variety of pure gases and calibration gas mixtures are required.Additionally, due to legal requirements, many of these gas mixtures will need to beaccreditated to international standards.Air Quality MonitoringInternational accords such as the Montreal protocol, or Kyoto accords call on all industryeverywhere to monitor, control and reduce their emissions before discharging them intothe environment. There are a number of different particulate and gaseous emissionswhich result from smoke stack emmissions in many industriesincluding manufacturing, chemical and petrochemical, and power generation.
Areas of key measurement include:Carbon monoxide (CO) from industrial processes and incomplete combustion of wood, oil, gasand coal.Carbon dioxide (CO2) , Sulphur Dioxide (SO2), and Nitric oxides (NO and NO2) fromcombustion of gas, oil and coal.Hydrogen sulfide (H2S) and methyl mercaptan (CH3SH) from pulp and paper mills.Hydrocarbons resulting from incomplete combustion of fuels.ISO 3930 requirements for vehicle exhaust emission levels for carbon monoxide (CO), carbondioxide (CO2), hydrocarbons (HC, in terms of n-hexane), and oxygen (O2).In all areas, a variety of environmental pure gases and calibration gas standards are required.Additionally, due to legislative, and/or legal requirements, many of these standards will needwhich need manufacturing to accreditation levels.
The gas atmosphere must be chosen with due consideration of the particular foodstuff andits properties. For low-fat products with a high moisture content, it is especially the growthof micro-organisms that has to be inhibited by using Carbon dioxide. On the other hand,should the product have a high fat content and low water activity, oxidation protection ismost important and inert Nitrogen would be the preferred choice.Food packagingModified Atmosphere Packaging of food, or MAP, is a natural shelf-life-enhancing method thatis growing rapidly on an international scale. It often complements other techniques, such ashigh-pressure and microwave methods or oxygen absorption. The correct gas mixture in MAPmaintains high quality by retaining the original taste, texture and appearance of the foodstuff.
Laser Cutting & WeldingLinde technology is being used constantly the world over in laser applications – inmanufacturing, metallurgy, chemicals, food processing, medicine, alternative fuel technologies& environmental technology. The LASERLINE® concept of high purity gas products andcomprehensive services, applications know-how along with cost efficient gas supplyoptions forms the basis for customised solutions that maximise productivityLeak TestingProducing tight systems is necessary, no matter if you produce tanks for the space shuttle,automotive gas tanks or gas ditribution systems. Other typical leak test objects are air bagsand pace makers, and anyone can understand what a disaster these could cause if not tight.Leak testing is often done with a gas or gas mixture together with a "sniffer" which is aspecialized mass spectrometer (MS.) Gas tanks and distribution systems are checked withhelium or helium mixtures while automotive systems often are checked with sulphurhexafluoride
Rapid Analysis of Pesticide Residues in Green Beans:Pesticide analysis is extremely important due to the need to ensure that foodstuff is notcontaminated with pesticide residues, which can be harmful to human health. Pesticideanalysis poses a number of challenges for laboratories due to the wide ranging chemistrieswithin the contaminants.Scientists have used gas chromatography-mass spectrometry (GC-MS) to obtain samples inorder to construct an in-depth human glomerulus proteome database.They hope the database will help increase the understanding of renal disease pathogenesis,as well aiding biomarker exploration.
Gas chromatography-mass spectrometry used to look at alternative insecticides for control of malariaGas chromatography-mass spectrometry has been used to look intothe intesecticidal activity of the essential oils in fruits and seeds takenfrom Schinus terebinthifolia Raddiagainst Africa malaria and filarial vectors.Reported in the Parasites & Vectors journal, research assessed the plant oil againstAnopheles gambiae s.s, An.arabiensis and Culex quinquefasciatus.The twenty third instar larvae of theAnopheles gambiaes.s and Cx. quinquefasciatus were exposed to different dosagesof the oil, with mortality rates being observed at 12, 24, 48 and 72 hours.
Barbiturates and benzodiazepines are usually encountered by the forensic scientistas tablet or capsule preparations that have been diverted from licit sources, or,particularly in the case of barbiturates, as ‘cutting agents’ in other drug materials(for example, phenobarbitone in heroin samples).In some cases, identification and confirmation of the dose form can be achievedby using internationally available databases. If this is not possible, then thetraditionalprocess of physical description, presumptive testing, TLC and GC–MSshould be followed to identify the drug components. However, somebenzodiazepinesare thermally labile and in such cases HPLC, possibly with diode-arraydetection, is often the chosen method of analysis. The latter technique is, inaddition, the preferred method for quantification purposes.Such drugs, when obtained from licit sources, are very pure and it is thereforeparticularly difficult, if not impossible, to compare the samples in order todetermine if they once originated from the same batch.
novel method for a rapid measurement of the volatile compounds of foodA fruit juice should not contain ethanol, but in some cases a fermentation can occur. Themaximum ethanol concentration allowed is 0.5% vol. We were asked to propose a rapidmethod for the measurement of this ethanol content. The method was as follows: Applejuice (8ml) was placed in a 22ml vial and ethanol was added in order to obtain aconcentration of between 0.05 and 0.5% vol. The sample was thermostatised at 30°C for30min. The head-space was sampled using a SPME-fiber, with an adsorption time of 2min. The desorption took place in the TV9000 in 1 min. The signal was measured with aFID. The Fig. 5 shows the correlation between the amount of ethanol added and thearea of the signal, for both standard ethanol solutions and spiked samples. The high areabefore any addition of ethanol (0 concentration) comes from the volatile compounds ofthe apple juice. Using this method, we can determine the concentration of ethanol inapple juice, and also monitor the evolution of ethanol during the fermentation of applejuice.ConclusionThe TV 9000 is...Simple........Robust........Easy to use........
Analysis of Anabolic Steroids for Doping Control Purposes by GCIn this application note, the performance of both one dimensional GC-TOFMS and GCxGC-TOFMS were evaluated, with special attention to the detectability and the confirmationreliability at low ppb concentration. For this purpose, five anabolic steroids were selected,for which very low detection limits (2 ng/mL) are required by the World Anti-DopingAgency.Qualitative Comparison of Whisky Samples Using Fast GC.In quality control of alcoholic beverages it is often important to compare differentproduction batches to detect possible changes in the fermentation and/or distillationprocess. This note describes theapplication of a simple and fast GC method with MSdetection using the Pegasus II Timeof-Flight GC/MS detector.The Application of GC/MS to the Analysis of Pesticides in FoodstuffsPesticide contamination of foodstuffs has become a worldwide concern, prompting variouslevels of regulation and monitoring.The discovery of the structure of insulin, for example, was made possible when the Britishbiochemist, Frederick Sanger, rationally and methodically applied the technique to thefragments of the ruptured insulin molecule, for which he received the 1958 Nobel prize forchemistry
Because of its simplicity, sensitivity, and effectiveness in separating components ofmixtures, gas chromatography is one of the most important tools in chemistry. It iswidely used for quantitative and qualitative analysis of mixtures, for the purification ofcompounds, and for the determination of such thermochemical constants as heats ofsolution and vaporization, vapour pressure and activity coefficients. Gaschromatography is also used to monitor industrial processes automatically: gas streamsare analysed periodically and manual or automatic responses are made to counteractundesirable variations. Many routine analyses are performed rapidly in environmentaland other fields. For example, many countries have fixed monitor points tocontinuously measure the emission levels of for instance nitrogen dioxides, carbondioxide and carbon monoxide. Gas chromatography is also useful in the analysis ofpharmaceutical products, alcohol in blood, essential oils and food products.
Gas chromatography is widely used for the separation and analysis of mixtures of manyCompounds at very low concentrations .The compounds which has low boiling points lower than 300oC can be easily analyzed by thisTechnique.The main areas of application of gas chromatography are1. Analalysis of toxic compounds, solvents, hydrocarbons as well as in forensic field,2. Polution studies, environmental analysis.Gas chromatography is mainly used in Pharmaceutical industry for the quantitative as well asQualitative estimation of solid, liquid and gaseous organic compounds.This technique is preferred over spectrophotometry and titration because the separationAs well as (both qualitative and quantitative can be carried out simultaneously.1.Qualitative analysis:Identification of the compound by GC either by following ways…1.Collecting the eluted vapours from the column and subjucting them to specific techniquelike Mass spectroscopy,I.R,U.V, NMR etc.b. The retention time here is used for qualitative analysis. Qualitative analysisThat is to say what is that peak.The retention time is simply a the time from the point of injection to the peakMaximum. That is the characteristic of this column and this system these conditions.
If the sample under test and the standard compounds are same , then under identicalConditions their resolution time are also same. Any deviation of graph from the standardIndicates the presence of a compound other than the standard.The relative retention R(samle/standard) specific retention volume of sample= ----------------------------------------------------------------------------Specific retention volume of standard2. Quantitative analysis:The next imp factor is the peak area.The peak area is used for peak concentration. Twice the concentration twice the peakArea. This peak area represents the amount of sample which is present in thePeak. One can also use peak height. The world countries do not have computesoften times simple rulers used for measuring peak heights. But In the modern worldcomputers and integrates peak areas easily obtained and the results printed outon the recorders.
Pharmaceutical applications : Chromatography plays imp. Role in the analysis ofpharmaceutical products and drugs.1. Quality control and analysis of drug products and in monitoring metabolites in biologicalFluids.Antibiotics Penicillins and its derivatives,Gentamycin, kanamycin ,Neomycin,tetracycline,chloramphenecol.etc.Anti T.B drugs Ethambutol, Isoniazid, Rifampicin.Anti cancer drugs 6-mercaptopurin,Flurouracil,Doxorubin,tomoxifen,Busulfan,Thiotepa,Melfalan.etc.Antivirals Amantidine,cytarabin,IdoxuridineCNS stimulants Caffeine, theophylline,NikethamideGeneral anaesthetics Chloroform, ether ,ethanol etc.Sydatives/ hypnotics Barbiturates,Gunathidine, Phenobarbitol (luminol), mephobarbitol,Benzodiazepens,Tranquiliazers( someMajor and minortranquilizers)Diazepam(Valium),Chlordiazepoxide (Librium),Flurazepam(Dalmane),Alprazolam(Xanax),Lorazepam (Ativan),phenothiazine,identified and measured by GC .etc.Tri cyclicAntidepressants anditsImipramine,Desipramine,Imitriptyline,Nor triptyline
Drug Solid phase Liquid phase Mobile phase DetectorAtropinesulphateAcid washedsalinisedDiatomaceoussupport.3% w/w of coated withphenyl methyl siliconeFluid.Nitrogen FIDHomatropine Same as above Same as above Nitrogen FIDHyoscinehydrobromideeyeye drops.Same as above Same as above Nitogen FIDClove oil same as above 3% w/w ofPEG.Nitrogen FIDEthosuximidesyrupSame as above 3%w/w ofCyanopropyl methylphenyl,Silicone fluid.Nitrogen FIDSteric acid Same as above 15% w/w ofDiethyleneGlycolSuccinate polyster.Nitrogen FID
EthyloestrenolGlass column acidwashed silaniseddiatomaceoussupport.Coated with 3%w/w phenylmethyl silicone fluid.Nitorgen FIDEconazolenitrite creamsame Coated with 3%w/w pfphenyl methyl silicane fluidglass columnNitrogenFIDChloroxylenolsolutionSame Coated with 3% PEGNitrogenFIDFenfluramineHcl tabletsSame Coated with 10% PEG and2% W/W of KOH. NitrogenFIDLincomycinHclSame Coated with 3%W/W ofphenyl methyl silicone fluid HeliumFIDMianserin HCl Same Coated with 3% W/W Phenylmethyl silicone.Nitrogen FIDTroxidonecaps.Stainless steelcolumn packedwith porouspolymer beadsNitrogen FID
3. Isolation and identification of mixtures of plant extracts, carbohydrates, volatile oilsAmino acids, lipids proteins, preservatives, vitamins, colourants, flavours etc.4. Identification and determination of fatty acids.5. Determination of fate of the drugs in body fluids like plasma, serum, urine. Etc.6.Analysis of solvents, organic functional groups, natural fats ,alcoholic beverages etc.7. Determination of protective coatings like styrene monomer, vinyl toluene,toluenediisocyanate etc.Miscellaneous Applications:1. Gas chromatography is widely used in the analysis of fertilizers, rubber, cosmetics,perfumes,food products and petroleum products.2.For detection of steroids taken by athletes during international sports competitions.3. IN environmental studies for the isolation and identification of chlorinated pesticidslike DDT and BHC, organomercuric compounds, organophorous compounds,sulphur compounds etc.4. For the analysis of dairy products like milk, butter, cheese, etc., for the presence ofaldehyde, ketones, milk sugars and fatty acids. Gas-liquid chromatography is applicableto species with high critical temperatures and normal boiling points as high as 400° C.Substances that are solids at normal laboratory conditionswith molecular weights below 1,000 are best separated with liquid-solid or liquid-liquid systemsLower members of the molecular weight scale range are amenable tosupercritical-fluid separations. Size-exclusion methods areinvolved at molecular weights above 1,000. Field-flow fractionation extendsthe size range to colloids and microscopic particles.
Advantages of combining gas chromatograph and mass spectrographThere are several advantages of putting the two devices together in one instrument.For one, it finishes the process faster. The accuracy of both processes is also notattained when they are done separately. This is because the sample to be taken intothe mass spectrometer must be in its purest state. Once the process is done separatelyand the sample is taken out of the gas chromatograph, the sample will be tamperedand the results will differ. Also, when they are done separately, there are instances thatthe separated elements in the gas chromatograph have similar ionized fragmentpattern and can be misinterpreted by the mass spectrograph. At least with putting thetwo devices together in one instrument, the number of errors is reduced.
Environmental checking and cleaningHave you ever wondered how environmentalists said that our air is already polluted? How didthey come up with such statement? How did they identify the elements that pollute our air?This is where gas chromatography-mass spectrometry comes in. Supposedly, the air we breatheshould only be composed of O2. Through GC and mass spectrometry, the other elements thatmixed with O2 that make the air polluted are separated and identified each. Through GC andmass spectrometry, the field of environmental studies has widened.Criminal ForensicsCSI and NCIS have become the most popular criminal forensic TV series of all times. Have you everthought how they are able to solve crimes even without much physical evidences? GC and MS areresponsible for this. When a person is killed with the use of chemical, the chemical as well as thecriminal can be detected through this process. Even without the actual container of the chemical,it can still be detected through the blood sample of the victim. In arson cases, this is a techniqueused to solve the crime, specifically Pyrolysis Gas Chromatography. This is to identify theelements that caused the fire of the area.
Drug identificationSpecific drugs are prohibited on every state. In order to detect whether a person is takingthe illegal drugs, GC and MS is applied. Drug test makes use of these processes. Throughthis, the examiners can identify what drugs have entered the body of the person throughtheir urine, blood, and faeces sample.Security purposesSince the September 11, 2011 incident, US airports have made their security stricter. Toexecute this, all incoming and outgoing individuals of the United States have their baggageinspected through Thermo Detection. This process involves GCMS to detect whether thebaggage contains explosives.Analysis of food and beverages for nutrition purposes and perfumeOne way to identify the nutrition value of a certain food or drink is through GCMS. Theirelements are identified individually and are then analysed whether they should still betaken or not.
Environmental monitoring and cleanupGC-MS is becoming the tool of choice for tracking organic pollutants in theenvironment. The cost of GC-MS equipment has decreased significantly, and thereliability has increased at the same time, which has contributed to its increasedadoption in environmental studies. There are some compounds for which GC-MS is notsufficiently sensitive, including certain pesticides and herbicides, but for most organicanalysis of environmental samples, including many major classes of pesticides, it is verysensitive and effective.Criminal forensicsGC-MS can analyze the particles from a human body in order to help link a criminal to acrime. The analysis of fire debris using GC-MS is well established, and there is even anestablished American Society for Testing Materials (ASTM) standard for fire debrisanalysis. GCMS/MS is especially useful here as samples often contain very complexmatrices and results, used in court, need to be highly accurate.
C-MS is increasingly used for detection of illegal narcotics, and may eventually supplant drug-sniffing dogs. It is also commonly used in forensic toxicology to find drugs and/or poisons inbiological specimens of suspects, victims, or the deceased.SecurityA post–September 11 development, explosive detection systems have become a part of allUS airports. These systems run on a host of technologies, many of them based on GC-MS.There are only three manufacturers certified by the FAA to provide these systems,[citationneeded] one of which is Thermo Detection (formerly Thermedics), which produces the EGIS,a GC-MS-based line of explosives detectors. The other two manufacturers are BarringerTechnologies, now owned by Smiths Detection Systems, and Ion Track Instruments, part ofGeneral Electric Infrastructure Security Systems.Food, beverage and perfume AnalysisFoods and beverages contain numerous aromatic compounds, some naturally present in theraw materials and some forming during processing. GC-MS is extensively used for the analysisof these compounds which include esters, fatty acids, alcohols, aldehydes, terpenes etc. It isalso used to detect and measure contaminants from spoilage or adulteration which may beharmful and which is often controlled by governmental agencies, for example pesticides.
Gas chromatography–mass spectrometry (GC-MS) is a method that combinesthe features of gas-liquid chromatography and mass spectrometry to identifydifferent substances within a test sample. Applications of GC-MS include drugdetection, fire investigation, environmental analysis, explosives investigation,and identification of unknown samples. GC-MS can also be used in airportsecurity to detect substances in luggage or on human beings. Additionally, itcan identify trace elements in materials that were previously thought to havedisintegrated beyond identification.GC-MS has been widely heralded as a "gold standard" for forensic substanceidentification because it is used to perform a specific test. A specific testpositively identifies the actual presence of a particular substance in a givensample. A non-specific test merely indicates that a substance falls into acategory of substances. Although a non-specific test could statistically suggestthe identity of the substance, this could lead to false positive identification.
From war zones or scenes of natural disasters, news reporters often comment on thestench of decaying bodies. This characteristic malodour is made up of a complex mixtureof volatile compounds that might be useful in forensic pathology, to establish the causeof death and the post-mortem interval. In the normal world, this characteristic smell isalso well known to members of the police force, crime scene technicians, medical staffand forensic pathologists, as well as to some dogs. Its composition is the trigger used bytracker dogs to locate hidden bodies. The same odour is also recognised by insects thatquickly colonise a body once it begins to decay. Now, Greek researchers have suggestedthat the odour can be used to determine the time since death and possibly help toestablish the cause of death. First of all, they remind us that the VOCs that constitute thesmell arise from the same sources in each human corpse. Carbohydrates in the bodybreak down to give mainly oxygenated compounds (alcohols, aldehydes, ketones, acids,esters, ethers), proteins degrade to nitrogen, phosphorus and sulphur compounds,nucleic acids from nitrogen and phosphorus compounds and lipids decompose tonitrogen, phosphorus and oxygenated compounds and hydrocarbons. So, in theory,different decaying bodies should produce the same set of VOCs.(volatile organiccompounds) he adsorbed gases were analysed by thermal desorption GC/MS and thecomponents were identified from their retention times and mass spectra using acommercial database and an in-house database constructed from standard compounds.The results were described in Forensic Sci. Intl. 2005. A total of 86 substances wereidentified and quantified with the aid of internal standard compounds. he relatively highlevels of toluene were unexpected, leading the authors to hint at the possibility of toluenepoisoning of the victims. The high number of fatty acid esters found was explained inGC and the smell of death(corpses)
Sniffer dogs can track the scent of humanbodies