Nkhani zina za LC zothetsa mavuto sizikhala zachikale, chifukwa pali zovuta muzochita za LC, ngakhale ukadaulo wa zida ukuyenda bwino pakapita nthawi. Pali njira zambiri zomwe mavuto angabwere mu dongosolo la LC ndikutha ndi mawonekedwe owopsa.
Zakhala zosangalatsa kulemba ndime iyi ya "LC Troubleshooting" ndikuganizira mitu mwezi uliwonse, chifukwa mitu ina simachoka m'kalembedwe. Pamene mu kafukufuku wa chromatography mitu ina kapena malingaliro amachoka chifukwa amachotsedwa ndi malingaliro atsopano ndi abwinoko, pankhani yothetsa mavuto, popeza nkhani yoyamba yothetsa mavuto idawonekera m'magazini ino (zolemba za LC zidakalipobe) 1983 (1) .Pazaka zingapo zapitazi, ndayang'ana magawo angapo a LC Troubleshooting pazochitika zamakono zomwe zimakhudza madzi a chromatography (LC) (mwachitsanzo, kuyerekezera kwachibale kwa kumvetsetsa kwathu kwa zotsatira za kupanikizika pa kusunga [2] Zatsopano Zatsopano) Kutanthauzira kwathu kwa zotsatira za LC ndi momwe tingathetsere mavuto ndi mndandanda wamakono wa LC (Mwezi wa December wa 3), zomwe zidayamba kukhazikitsidwa kwa mwezi wa December. 2021, yomwe imayang'ana pamitu ina ya "moyo ndi imfa" ya LC yothetsa mavuto - zinthu zomwe zili zabwino kwa wothetsa mavuto aliyense ndizofunikira, ziribe kanthu zaka za dongosolo lomwe tikugwiritsa ntchito.Nkhani yaikulu ya mndandandawu ndi yogwirizana kwambiri ndi "LC Troubleshooting Guide" yotchuka ya LCGC (4) yopachikidwa m'ma laboratories ambiri. Makhalidwe.Chodabwitsa, tchati cha khoma chimatchula zifukwa 44 zosiyana zomwe zimapangitsa kuti zikhale zovuta kwambiri!
Ndimadzipeza ndikumayankha mafunso othetsa mavuto ndi "chilichonse ndi chotheka". Yankho ili limatha kuwoneka losavuta ndikaganizira zomwe ndizovuta kuzimasulira, koma ndimawona kuti ndizoyenera. Ndizifukwa zambiri zomwe zimapangitsa kuti pakhale zovuta, ndikofunikira kukhala ndi malingaliro omasuka poganizira zomwe vuto lingakhale, ndikuyika patsogolo zomwe zingayambitse kuti tiyambitse zovuta zathu, kuyang'ana kwambiri zomwe zingatheke.
Chinthu chofunika kwambiri pazochitika zilizonse zothetsera mavuto - koma zomwe ndikuganiza kuti ndizochepa - ndikuzindikira kuti pali vuto lomwe liyenera kuthetsedwa.Kuzindikira kuti pali vuto nthawi zambiri kumatanthauza kuzindikira kuti zomwe zimachitika ku chida ndi zosiyana ndi zomwe tikuyembekezera, zomwe zimapangidwira ndi chiphunzitso, chidziwitso champhamvu, ndi zochitika (5) . asymmetrical, yosalala, fluffy, kutsogolera m'mphepete, mchira, etc.), komanso ku m'lifupi.Zoyembekeza zathu za mawonekedwe enieni apamwamba ndi ophweka.Lingaliro (6) limathandizira bwino chiyembekezero cha bukuli kuti, nthawi zambiri, nsonga za chromatographic ziyenera kukhala zofanana ndi zofanana ndi mawonekedwe a Gaussian kugawa, monga momwe tawonetsera mu chithunzichi, chomwe tikuyembekezera kuchokera m'lifupi ndi 1. mutu m'nkhani yamtsogolo.Mawonekedwe ena apamwamba pachithunzi 1 akuwonetsa zina mwa zina zomwe zitha kuwonedwa-mwa kuyankhula kwina, njira zina zomwe zingasokonezeke.Mu gawo lotsala la gawoli, tikhala nthawi tikukambirana zitsanzo zenizeni za zochitika zomwe zingayambitse mitundu iyi ya mawonekedwe.
Nthawi zina nsonga sizimawonedwa konse mu chromatogram momwe zimayembekezeredwa kuchotsedwa.Tchati yapakhoma yomwe ili pamwambayi ikuwonetsa kuti kusakhalapo pachimake (poganiza kuti chitsanzocho chili ndi chowunikira chomwe chikuyenera kupangitsa kuti chowunikiracho chikhale chokwanira kuti chiziwone pamwamba pa phokoso) nthawi zambiri chimagwirizana ndi vuto la chida kapena mikhalidwe yolakwika ya gawo la foni (ngati iwonedwa konse). nsonga, nthawi zambiri "zofooka") .Mndandanda waufupi wamavuto omwe angakhalepo ndi mayankho mgululi akupezeka mu Gulu 1.
Monga tafotokozera pamwambapa, funso la kuchuluka kwa nsonga kuyenera kulekerera musanayambe kulabadira ndikuyesera kukonza ndi nkhani yovuta yomwe ndidzakambirana m'nkhani yamtsogolo. Zomwe ndikukumana nazo ndikuti kufalikira kwapamwamba kwambiri nthawi zambiri kumatsagana ndi kusintha kwakukulu kwa mawonekedwe apamwamba, ndipo nsonga zamtunduwu zimakhala zofala kwambiri kusiyana ndi chisanadze kapena kugawanika.
Nkhani zonsezi zakambidwa mwatsatanetsatane m'nkhani zam'mbuyo za Kuthetsa Mavuto a LC, ndipo owerenga omwe ali ndi chidwi pamituyi akhoza kutchula nkhani zam'mbuyomu kuti mudziwe zomwe zimayambitsa komanso njira zothetsera vutoli. Zambiri.
Kuthamanga kwapamwamba, kutsogolo kwapamwamba, ndi kugawanika kungayambitsidwe ndi zochitika za mankhwala kapena zakuthupi, ndipo mndandanda wa njira zothetsera mavutowa zimasiyana mosiyanasiyana, malingana ndi momwe tikulimbana ndi vuto la mankhwala kapena lakuthupi. nsonga imodzi yokha kapena zochepa zimakhudzidwa, koma zina zonse zimawoneka bwino, chifukwa chake ndi mankhwala.
Zomwe zimayambitsa nsonga zam'mwamba zimakhala zovuta kwambiri kuti tikambirane mwachidule apa.Wowerenga chidwi amatchulidwa ku nkhani yaposachedwa ya "LC Troubleshooting" kuti mukambirane mozama (10) .Komabe, chinthu chosavuta kuyesa ndikuchepetsa kuchuluka kwa analyte ojambulidwa ndikuwona ngati mawonekedwe apamwambawo akuyenda bwino.Ngati ndi choncho, ndiye kuti ichi ndi chidziwitso chabwino kuti vutoli liyenera kukhala lochepa, njira yochepetserayi ndi yochepa. ma analyte, kapena mawonekedwe a chromatographic akuyenera kusinthidwa kuti mawonekedwe apamwamba azitha kupezeka ngakhale atabaidwa ndi unyinji wokulirapo.
Palinso zifukwa zambiri zakuthupi zomwe zingatheke chifukwa cha kupendekera kwapamwamba.Owerenga omwe ali ndi chidwi chokambirana mwatsatanetsatane za zotheka amatumizidwa ku nkhani ina yaposachedwa ya "LC Troubleshooting" (11) . Chimodzi mwa zifukwa zofala kwambiri zakuthupi za nsonga zapamwamba ndi kugwirizana kosauka pakati pa jekeseni ndi detector (12) . zomwe sitinagwiritse ntchito kale, ndikuyika jekeseni yaing'ono ya voliyumu yokhala ndi ferrule yomwe idapangidwira pa capillary zitsulo zosapanga dzimbiri. Pambuyo poyesera kuthetsa mavuto oyambirira, tinazindikira kuti kuya kwa doko mu jekeseni wa valve stator kunali kozama kwambiri kuposa momwe tinazolowera, zomwe zimapangitsa kuti pakhale phokoso lalikulu lakufa pansi pa doko. kuchotsa voliyumu yakufa pansi pa doko.
Zomwe zimayambira pachimake ngati zomwe zikuwonetsedwa mu Chithunzi 1e zithanso kuyambitsidwa ndi zovuta zakuthupi kapena zamankhwala.Chomwe chimayambitsa nsonga yotsogola ndikuti bedi la tinthu tating'onoting'ono silinapakidwe bwino, kapena kuti tinthu tating'ono tating'ono takonzedwanso pakapita nthawi.Monga momwe zimakhalira pachimake chifukwa cha chodabwitsa ichi, njira yabwino yothetsera izi ndikusintha chigawocho ndikupitilizabe zomwe zimayambira poyambira, zomwe zimayambira poyambira. Mikhalidwe yosungira "yopanda mzere". Pansi pazikhalidwe zabwino (zotsatira), kuchuluka kwa analyte komwe kumasungidwa ndi gawo loyima (motero, chinthu chosungira) chimagwirizana mwachindunji ndi kusakanikirana kwa analyte mu column. Kuonjezera apo, mawonekedwe osakhala a mzere amatsimikizira mawonekedwe a nsonga za chromatographic, zomwe zimapangitsa kuti pakhale nsonga zotsogola kapena zotsatira. m'mphepete, kapena mawonekedwe a chromatographic ayenera kusinthidwa kuti achepetse izi.
Nthawi zina timawona zomwe zimawoneka ngati "kugawanika" pachimake, monga momwe tawonetsera mu Chithunzi 1f. Njira yoyamba yothetsera vutoli ndiyo kudziwa ngati mawonekedwe apamwamba amachokera ku mgwirizano wapang'ono (ie, kukhalapo kwa mitundu iwiri yosiyana koma yosakanikirana kwambiri). "kugawanika" nsonga zikugwirizana ndi thupi Magwiridwe alibe kanthu kochita ndi mzati wokha.Nthawi zambiri, chidziwitso chofunikira kwambiri pa chisankho ichi ndi chakuti nsonga zonse za chromatogram zimasonyeza mawonekedwe ogawanika, kapena chimodzi kapena ziwiri. ngati nsonga zonse zagawanika, mwina ndi nkhani yakuthupi, yokhudzana ndi gawo lomwelo.
Kugawanika nsonga zokhudzana ndi maonekedwe a thupi la gawolo nthawi zambiri zimakhala chifukwa cha kutsekedwa pang'ono kolowera kapena kutuluka kwa frits, kapena kukonzanso kwa tinthu tating'onoting'ono tating'onoting'ono, kulola kuti gawo la mafoni liziyenda mofulumira kusiyana ndi gawo la mafoni m'madera ena a mapangidwe a ndondomeko .m'madera ena (11) . komabe, muzochitika zanga, izi nthawi zambiri zimakhala zaufupi kusiyana ndi nthawi yayitali.Izi nthawi zambiri zimapha ndi mizati yamakono ngati tinthu tating'ono timagwirizanitsanso mkati mwa chigawocho.Panthawiyi, ndibwino kuti musinthe ndondomekoyi ndikupitirizabe.
Pachimake mu Chithunzi 1g, komanso kuchokera ku zochitika zaposachedwa mu labu yanga, nthawi zambiri zimasonyeza kuti chizindikirocho ndi chapamwamba kwambiri moti chafika kumapeto kwa chiwerengero choyankhira.Kwa optical absorbance detectors (UV-vis mu nkhani iyi), pamene ndende ya analyte ndi yokwera kwambiri, analyte imatenga kuwala kwakukulu komwe kumadutsa mu selo loyendetsa galimoto, kusiya mikhalidwe yochepa kwambiri ya kuwala kwa magetsi. kukhudzidwa kwambiri ndi magwero osiyanasiyana a phokoso, monga kuwala kosokera ndi "mdima wakuda", kupangitsa chizindikirocho kukhala "chosawoneka bwino" komanso chosagwirizana ndi ndende ya analyte. Izi zikachitika, vutoli likhoza kuthetsedwa mosavuta pochepetsa kuchuluka kwa jekeseni wa analyte-kuchepetsa mphamvu ya jekeseni, kuchepetsa chitsanzo, kapena zonse ziwiri.
M'sukulu ya chromatography, timagwiritsa ntchito chizindikiro cha detector (ie, y-axis mu chromatogram) monga chizindikiro cha ndende ya analyte mu sampuli.Choncho zikuwoneka zosamvetseka kuona chromatogram yokhala ndi chizindikiro pansi pa ziro, monga kutanthauzira kosavuta ndiko kuti izi zimasonyeza kusokonezeka kwa analyte - zomwe ndithudi sizingatheke mwakuthupi. (mwachitsanzo, UV-vis).
Pachifukwa ichi, nsonga yoyipa imangotanthauza kuti mamolekyu omwe amatuluka kuchokera pamzati amamwa kuwala kochepa kusiyana ndi gawo loyendetsa mafoni nthawi yomweyo isanayambe komanso itatha pachimake. Izi zikhoza kuchitika, mwachitsanzo, pogwiritsa ntchito mafunde otsika kwambiri (<230 nm) ndi zowonjezera zowonjezera zomwe zimatenga kuwala kwakukulu pa mafundewa. gwiritsani ntchito nsonga zolakwika kuti mukonzekere nsonga yokhotakhota ndikupeza zidziwitso zolondola za kuchuluka kwake, kotero palibe chifukwa chofunikira kuzipewa pa sekondi iliyonse (njira imeneyi nthawi zina imatchedwa "kuzindikira kwa UV kosalunjika") (13) . gawo kotero kuti Iwo amayamwa kuwala pang'ono kuposa analytes.
Nsonga zopanda pake zimatha kuwonekeranso mukamagwiritsa ntchito kuzindikira kwa refractive index (RI) pomwe index ya refractive ya zigawo zina kupatula ma analyte mu zitsanzo, monga zosungunulira matrix, ndizosiyana ndi refractive index of the mobile phase. gawo.
Mu gawo lachitatu pa mutu waukulu wa LC troubleshooting, ine tinakambirana zinthu zimene anaonedwa pachimake mawonekedwe amasiyana ndi kuyembekezera kapena yachibadwa pachimake mawonekedwe.Kuthetsa mavuto mogwira mtima wa mavuto amenewa kumayamba ndi chidziwitso cha kuyembekezera akalumikidzidwa pachimake (kutengera chiphunzitso kapena zinachitikira m'mbuyomu ndi njira zomwe zilipo), kotero kupatuka kwa ziyembekezo izi n'zoonekeratu. Pachimake mawonekedwe mavuto ali ndi zifukwa zambiri zosiyana, kutsogolera m'mbali mwa kukhazikitsa, ndi zina zotero. zifukwa zomwe ndimawona nthawi zambiri.Kudziwa tsatanetsatane kumapereka malo abwino oyambira kuthetsa mavuto, koma sikujambula zotheka zonse.Owerenga omwe ali ndi chidwi ndi mndandanda wozama wazomwe zimayambitsa ndi njira zothetsera mavuto angatchule tchati cha khoma la LCGC "LC Troubleshooting Guide".
(4) LCGC “LC Troubleshooting Guide” wall chart.https://www.chromatographyonline.com/view/troubleshooting-wallchart (2021).
(6) A. Felinger, Data Analysis ndi Signal Processing mu Chromatography (Elsevier, New York, NY, 1998), pp. 43-96.
(8) Wahab MF, Dasgupta PK, Kadjo AF ndi Armstrong DW, Anal.Chim.Journal.Rev. 907, 31–44 (2016).https://doi.org/10.1016/j.aca.2015.11.043.