Table Of ContentDerivatization
in Analytical
Chemistry
Edited by
Paraskevas D. Tzanavaras
Printed Edition of the Special Issue Published in Molecules
www.mdpi.com/journal/molecules
Derivatization in Analytical Chemistry
Derivatization in Analytical Chemistry
Editor
Paraskevas D. Tzanavaras
MDPI‚Basel‚Beijing‚Wuhan‚Barcelona‚Belgrade‚Manchester‚Tokyo‚Cluj‚Tianjin
Editor
ParaskevasD.Tzanavaras
Chemistry
AristotleUniversity
Thessaloniki
Greece
EditorialOffice
MDPI
St. Alban-Anlage66
4052Basel,Switzerland
ThisisareprintofarticlesfromtheSpecialIssuepublishedonlineintheopenaccessjournalMolecules
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Contents
Prefaceto”DerivatizationinAnalyticalChemistry” . . . . . . . . . . . . . . . . . . . . . . . . . vii
ApostoliaTsiasioti,ConstantinosK.ZacharisandParaskevasD.Tzanavaras
Single-Step Hydrolysis and Derivatization of Homocysteine Thiolactone Using Zone
Fluidics: Simultaneous Analysis of Mixtures with Homocysteine Following Separation by
Fluorosurfactant-ModifiedGoldNanoparticles
Reprintedfrom: 2022,27,2040,doi:10.3390/molecules27072040 . . . . . . . . . . . . . . . . . . . 1
AnkhbayarLkhagvaandHwan-ChingTai
Dimethylcysteine (DiCys)/o-Phthalaldehyde Derivatization for Chiral Metabolite Analyses:
Cross-ComparisonofSixChiralThiols
Reprintedfrom: 2021,26,7416,doi:10.3390/molecules26247416 . . . . . . . . . . . . . . . . . . . 11
DimitriosTsikas
GC-MSAnalysisofBiologicalNitrateandNitriteUsingPentafluorobenzylBromideinAqueous
Acetone:ADualRoleofCarbonate/BicarbonateasanEnhancerandInhibitorofDerivatization
Reprintedfrom: 2021,26,7003,doi:10.3390/molecules26227003 . . . . . . . . . . . . . . . . . . . 23
PetraHorka´,Vladim´ırVrkoslav,Jirˇı´Kindl,KarolinaSchwarzova´-Peckova´ andJosefCvacˇka
StructuralCharacterizationofUnusualFattyAcidMethylEsterswithDoubleandTripleBonds
UsingHPLC/APCI-MS2withAcetonitrileIn-SourceDerivatization
Reprintedfrom: 2021,26,6468,doi:10.3390/molecules26216468 . . . . . . . . . . . . . . . . . . . 39
Kyong-OhShinandKyunghoPark
A Newly Developed HPLC-UV/Vis Method Using Chemical Derivatization with
2-NaphthalenethiolforQuantitationofSulforaphaneinRatPlasma
Reprintedfrom: 2021,26,5473,doi:10.3390/molecules26185473 . . . . . . . . . . . . . . . . . . . 61
CarlosA.ValdezandRoaldN.Leif
Analysis of Organophosphorus-Based Nerve Agent Degradation Products by Gas
Chromatography-Mass Spectrometry (GC-MS): Current Derivatization Reactions in the
AnalyticalChemist’sToolbox
Reprintedfrom: 2021,26,4631,doi:10.3390/molecules26154631 . . . . . . . . . . . . . . . . . . . 71
Shusuke Uekusa, Mayu Onozato, Tatsuya Sakamoto, Maho Umino, Hideaki Ichiba and
KenjiOkoshietal.
Development of a Derivatization Reagent with a 2-Nitrophenylsulfonyl Moiety for
UHPLC-HRMS/MSandItsApplicationtoDetectAminoAcidsIncludingTaurine
Reprintedfrom: 2021,26,3498,doi:10.3390/molecules26123498 . . . . . . . . . . . . . . . . . . . 89
KatarzynaKurpet,RafałGłowackiandGraz˙ynaChwatko
Simultaneous Determination of Human Serum Albumin and Low-Molecular-Weight Thiols
afterDerivatizationwithMonobromobimane
Reprintedfrom: 2021,26,3321,doi:10.3390/molecules26113321 . . . . . . . . . . . . . . . . . . . 101
OlgaBegou,KathrinWeber,BibianaBeckmannandDimitriosTsikas
GC-MSStudiesonDerivatizationofCreatinineandCreatinebyBSTFAandTheirMeasurement
inHumanUrine
Reprintedfrom: 2021,26,3206,doi:10.3390/molecules26113206 . . . . . . . . . . . . . . . . . . . 119
v
SvetlanaBaskal,AlexanderBollenbachandDimitriosTsikas
GC-MS Discrimination of Citrulline from Ornithine and Homocitrulline from Lysine
by Chemical Derivatization: Evidence of Formation of N5-Carboxy-ornithine and
N6-Carboxy-lysine
Reprintedfrom: 2021,26,2301,doi:10.3390/molecules26082301 . . . . . . . . . . . . . . . . . . . 137
EliiseTammekivi,SigneVahur,MartinVilbasteandIvoLeito
Quantitative GC–MS Analysis of Artificially Aged Paints with Variable Pigment and Linseed
OilRatios
Reprintedfrom: 2021,26,2218,doi:10.3390/molecules26082218 . . . . . . . . . . . . . . . . . . . 149
SvetlanaBaskal,AlexanderBollenbachandDimitriosTsikas
Two-Step Derivatization of Amino Acids for Stable-Isotope Dilution GC–MS Analysis:
Long-TermStabilityofMethylEster-PentafluoropropionicDerivativesinTolueneExtracts
Reprintedfrom: 2021,26,1726,doi:10.3390/molecules26061726 . . . . . . . . . . . . . . . . . . . 163
YunAi,YanNiSun,LiLiu,FangYuanYao,YanZhangandFengYiGuoetal.
Determination of Biogenic Amines in Different Parts of Lycium barbarum L. by HPLC with
PrecolumnDansylation
Reprintedfrom: 2021,26,1046,doi:10.3390/molecules26041046 . . . . . . . . . . . . . . . . . . . 173
Ibrahim A. Darwish, Hany W. Darwish, Nasr Y. Khalil and Ahmed Y. A. Sayed
Experimental and Computational Evaluation of Chloranilic Acid as an Universal
Chromogenic Reagent for the Development of a Novel 96-Microwell Spectrophotometric Assay
for Tyrosine Kinase Inhibitors
Reprintedfrom: 2021,26,744,doi:10.3390/molecules26030744 . . . . . . . . . . . . . . . . . . . . 185
vi
Preface to ”Derivatization in Analytical Chemistry”
Derivatization is one of the most widely used sample pretreatment techniques in Analytical
Chemistry and Chemical Analysis. Reagent-based or reagent-less schemes offer improved
detectability of target compounds, modification of the chromatographic properties and/or the
stabilization of sensitive compounds until analysis. Either coupled with separation techniques or
as a “stand alone” analytical procedure, derivatization offers endless possibilities in all aspects
of analytical applications.
ParaskevasD.Tzanavaras
Editor
vii
molecules
Article
Single-Step Hydrolysis and Derivatization of Homocysteine
Thiolactone Using Zone Fluidics: Simultaneous Analysis of
Mixtures with Homocysteine Following Separation by
Fluorosurfactant-Modified Gold Nanoparticles
ApostoliaTsiasioti1,ConstantinosK.Zacharis2 andParaskevasD.Tzanavaras1,*
1 LaboratoryofAnalyticalChemistry,SchoolofChemistry,FacultyofSciences,
AristotleUniversityofThessaloniki,54124Thessaloniki,Greece;[email protected]
2 LaboratoryofPharmaceuticalAnalysis,DepartmentofPharmaceuticalTechnology,SchoolofPharmacy,
AristotleUniversityofThessaloniki,54124Thessaloniki,Greece;[email protected]
* Correspondence:[email protected];Tel.:+30-23-1099-7721
Abstract:Herein,wereportanewautomatedflowmethodbasedonzonefluidicsforthesimulta-
neousdeterminationofhomocysteineandhomocysteinethiolactoneusingfluorimetricdetection
(λext=370nm/λem=480nm).Homocysteinethiolactoneishydrolyzedon-lineinalkalinemedium
(1molL−1NaOH)toyieldhomocysteine,followedbyreactionwitho-phthalaldehydeinasingle
step. Derivatizationisrapidwithouttheneedofelevatedtemperaturesandstopped-flowsteps,
whilespecificityisachievedthroughauniquereactionmechanismintheabsenceofnucleophilic
compounds.Mixturesoftheanalytescanbeanalyzedquantitativelyafterspecificseparationwith
fluorosurfactant-cappedgoldnanoparticlesthatareselectivelyaggregatedbyhomocysteine,leaving
Citation:Tsiasioti,A.;Zacharis,C.K.;
thethiolactoneanalogueinsolution.Aslowas100nmolL−1oftheanalyte(s)canbequantifiedin
Tzanavaras,P.D.Single-Step
aqueoussolutions,whileconcentrations>2µmolL−1 canbeanalyzedinartificialandrealurine
HydrolysisandDerivatizationof
HomocysteineThiolactoneUsing matrixfollowing20-folddilution.Thepercentrecoveriesrangedbetween87and119%.
ZoneFluidics:Simultaneous
AnalysisofMixtureswith Keywords:homocysteinethiolactone;homocysteine;zonefluidics;o-phthalaldehyde;fluorosurfactant-
HomocysteineFollowingSeparation modifiedgoldnanoparticles
byFluorosurfactant-ModifiedGold
Nanoparticles.Molecules2022,27,
2040. https://doi.org/10.3390/
molecules27072040 1. Introduction
AcademicEditor:JoselitoP.Quirino Homocysteinethiolactone(HTL)isawell-knownmodifyingfactorofproteins,andits
roleinthepathogenesisofdifferentdiseaseshasstartedtoberecognized[1–4]. HTLisa
Received:11February2022
chemicallyreactivemetabolitegeneratedbymethionyl-tRNAsynthetaseandclearedby
Accepted:20March2022
thekidney[5]. TherearenumerousrecentstudiestryingtoelucidatetheroleofHTLin
Published:22March2022
humanhealth,includingtheoxidativestatusofliverandintestines[6],spermfunction[7],
Publisher’sNote:MDPIstaysneutral bloodvesseldisfunction[8],andcardiovasculardiseases[9].
withregardtojurisdictionalclaimsin HTL has, therefore, attracted the interest of analytical chemists and there are var-
publishedmapsandinstitutionalaffil- ious methods in the literature reporting its determination in biological material, either
iations.
alone [10–16] or in combination with HCY [17–19]. Due to the complexity of the bio-
logicalmatrices,themajorityofthemethodstakeadvantageoftheenhancedselectivity
featuresofseparationinstrumentaltechniques,suchasgaschromatography(GC)[11,13,17],
liquidchromatography(HPLC)[15,16,18],andcapillaryelectrophoresis[10,12,19,20]. Elec-
Copyright: © 2022 by the authors.
trophoretictechniquesofferlowoperationalcostsandhighseparationefficiencybutgen-
Licensee MDPI, Basel, Switzerland.
erally low sensitivity. HTL/HCY can be detected directly using simple UV detection,
This article is an open access article
butsensitivityenhancementtosub-micromolarlevelsrequirespreconcentrationbyeither
distributed under the terms and
single-dropmicroextraction(SDME)[10,20],orbyfield-amplifiedsamplestacking[10,12].
conditionsoftheCreativeCommons
Attribution(CCBY)license(https:// GC-MSisreportedtobeabletodetectHTL/HCYselectivelyatmicromolarlevelswith
creativecommons.org/licenses/by/ aderivatization/extractionstepalwaysbeingnecessarytoimprovethevolatilityofthe
4.0/). analytes[11,13,17]. HPLCisconsideredtobebyfarthemostwidelyappliedtechniquein
1
Molecules 2022, 27, x FOR PEER REVIEW 2 of 9
derivatization/extraction step always being necessary to improve the volatility of the an-
alytes [11,13,17]. HPLC is considered to be by far the most widely applied technique in
bioanalysis and there are a couple of recent elegant reports on the analysis of HTL/HCY.
For example, HTL/HCY were derivatized with o-phthalaldehyde on-column (the reagent
Molecules2022,27,2040
was incorporated in the mobile phase), resulting in sharp peaks and fast elution. How-
ever, the stability of the reversed phase column under highly alkaline conditions (0.1 mol
bLio-1a nNaalyOsiHsa innd tthhee rmeaorbeialec opuhpaleseo)f rsehcoenutldel eaglawnatyresp boert soof ncothnecaenranl y[s1i3s]o. fAHlTteLr/nHaCtiYv.eFlyor, the ana-
elxyatme(psl)e c,aHnT bLe/ HdeCtYerwmeirneedde rbiyv aHtizPeLdCw ditihreoc-ptlhyt h(UalVal daet h2y4d0e nomn-)c o[1lu6m] onr( athfteerre pagoesnt-tcwolausmn deri-
invcaotirzpaotriaotned cionmthbeinmeodb wileitphh caaseti)o,rne seuxlctihnagninges hpaurprifpiecaaktisoann d[1f5a]s.t elution. However,the
stabilityofthereversedphasecolumnunderhighlyalkalineconditions(0.1molL–1NaOH
In our previous work, we have studied the selective reaction of HCY with o-phthalal-
inthemobilephase)shouldalwaysbeofconcern[13]. Alternatively,theanalyte(s)can
dehyde (OPA) in highly alkaline medium under flow conditions using the concept of zone
bedeterminedbyHPLCdirectly(UVat240nm)[16]orafterpost-columnderivatization
fluidics (ZF) [21]. Herein, we expand our work on investigating the potential of simulta-
combinedwithcationexchangepurification[15].
neous determining of HCY and HTL based on the rapid alkaline hydrolysis of the latter
Inourpreviouswork,wehavestudiedtheselectivereactionofHCYwitho-phthalaldehyde
(OunPAde)rin flhoiwgh clyonaldkiatliionnesm [e2d2i]u. mOuurn gdoeralfl iosw toc oancdhiiteiovnes quusainngtitthaeticvoen cceopntvoefrzsoionne flouf iHdiTcsL to HCY
(aZnFd) [d21e]r.ivHaetirzeainti,owne wexitpha nOdPoAu rinw ao rskinognlei nrvuens.t iAgantianlgystihse opf omteinxttiualreosf issim auccltoamnepoluisshed by a
dseimterpmlein (icnegnotrfiHfuCgYataionnd-HbaTsLedb)a saenddo enlethgeanrat poifdf-alilknael isnteeph ybdarsoeldy soisno tfhteh edliaffteterrenutn dinetreractions
floofw thceo nadniatiloyntess[ 2w2]i.thO uflrugooraolsiusrtfoacatcahniet v(eFSqNua)n-mtitoadtivifeiecdo ngvoelrds ionnanoofpHaTrLtictoleHs (CGYNaPnds) [14]. To
derivatizationwithOPAinasinglerun. Analysisofmixturesisaccomplishedbyasimple
the best of our knowledge, this is the first automated flow assay for HTL reported in the
(centrifugation-based)andelegantoff-linestepbasedonthedifferentinteractionsofthe
literature.
analyteswithfluorosurfactant(FSN)-modifiedgoldnanoparticles(GNPs)[14]. Tothebest
ofourknowledge,thisisthefirstautomatedflowassayforHTLreportedintheliterature.
2. Results and Discussion
22..R1.e HsuyldtsroalnydsiDs oisf cHusTsLio unnder Flow Conditions
2.1. HydrolysisofHTLunderFlowConditions
HCY reacts with OPA under flow conditions and in highly alkaline medium (0.5 mol
HCYreactswithOPAunderflowconditionsandinhighlyalkalinemedium(0.5molL−1
L−1 NaOH [21]) to form a highly fluorescent derivative in the absence of nucleophilic rea-
NaOH[21])toformahighlyfluorescentderivativeintheabsenceofnucleophilicreagents.
gents. The chemical system is specific in the presence of cysteine and other common amino
Thechemicalsystemisspecificinthepresenceofcysteineandothercommonaminoacids
acids and highly selective against histidine, histamine, and glutathione. On the other
andhighlyselectiveagainsthistidine,histamine,andglutathione. Ontheotherhand,HTL
hand, HTL can react with the derivatizing reagent only after cleavage of the thiolactone
canreactwiththederivatizingreagentonlyaftercleavageofthethiolactoneringtoyield
HriCnYg (tFoi gyuiereld1 )H[2C2Y]. (Figure 1) [22].
FFigiguurere1 .1H. Hydyrdolryosliyssoisf hoof mhoocmysotceyinsetetihnioel athctioonlaecutonndeer uanlkdaelirn aelckoanlidnitei ocnosn.ditions.
Thepotentialofautomatingthehydrolysisandderivatizationinasinglestepunder
The potential of automating the hydrolysis and derivatization in a single step under
zone fluidics was investigated using the setup described in Section 3.2. Equal amount
zone fluidics was investigated using the setup described in Section 3.2. Equal amount con-
concentrationsofHCYandHTL(aqueoussolutionsof0.75µmolL−1each)wereprocessed
sceeqnuternattiiaollnysu osifn gHeCleYv aatinndg cHonTcLe n(tarqatuioenosuosf sNoalOutHio(n0s.5 otof 20..07m5 oμlmL−o1l) .LT−1h eeaecxhpe) rwimeernet aplrocessed
sequentially using elevating concentrations of NaOH (0.5 to 2.0 mol L−1). The experimental
resultsaredepictedinFigure2andclearlydemonstratetheeffectivehydrolysisofHTL
(r9e7s–u10lt1s% a)raet daellpNicatOedH ilne vFeilgsu(aret [2N aanOdH c]l>ea1rlmyo dleLm−1o,nthsetrsaetnes tihtiev ietyffdecetcirveea shedyderqoulaylslyis of HTL
f(o9r7b–o1t0h1%an)a alyt taelsl) .NIatOisHa llseovwelos r(taht m[NenaOtioHn]in >g 1t hmaotln Lo−h1,e tahtein sgenofsitthiveirtyea dcteicorneacoseildn eoqrually for
sbtooptphe adn-flaolywtews)a.s Int eisc easlssaor ywtoorimthp mroevnettihoencilnegav tahgaet onfot hheetahtiionlgac otofn teheri nrega,csitmiopnl icfyoiinl gntohre stopped-
ofnlo-lwin ewaasssa ny.eBceassseadroyn toth eimfipndroinvges tihneF cigleuareva2g,ae coofn tcheen ttrhatiioolnacotfoNnea OriHngo,f s1i.m0mploilfyLi−n1g the on-
wlianses ealsescateyd. Bfoarsfeudr tohner tehxep feirnimdienngtss. in Figure 2, a concentration of NaOH of 1.0 mol L−1 was
selected for further experiments.
2
MMoleocluecleusle2s0 22022,22,7 2,72,0 x4 0FOR PEER REVIEW 3 of 9
FiFgiugruer2e. 2E. fEfeffcetcot fotfh tehceo cnocnecnetnratrtaiotinono foNf NaOaOHHo nonth tehhe yhdyrdorloylsyissiosf ohf ohmomocoycsytesitneienteh tiholiaoclatoctnoen.e.
InIna af ofolllolowwininggs seerriieess ooff eexxppeerriimmeennttss,, tthhee eeffffeecctitvivee clcelaeavvagage eofo tfhteh tehtiholiaoclatocntoen reinrgin ugn-
unddeer rflflooww ccoonnddiittiioonnss wwaass iinnvveessttiiggaatteedd aatt tthhee eennttiirree pprraaccttiiccaalll ilnineeaarritiytyr arannggeei nint htheea ratritfiicfiicailal
uruirnienem matartixrix(2 (2to to30 3µ0 mμmoloLl −L1−)1.).T Thheee exxppeerrimimeenntatallp prorocecedduurerei ninvvoolvlvededt hthees tsetpepssd edsecsrcirbiebded
ininS eScetciotinon3 .34.4u nudnedretrh tehe“ A“Ananlaylsyissiso foHf HCYC+YH+HTLT”L.”.T Thheer artaitoioo foft htehes lsolpoepseso fotfh tehec ucruvrevses
(2(92.93.(3± (±00.8.8))f oforrH HTTLLa nandd2 92.98.8( ±(±00..66))f foorrH HCCYY))i ninddicicaatetedd9 988.3.3%%c oconnvveersrisoionnw witihthininth tehew whohloele
cocnocnecnetnrtartaiotinonra rnagneg.e.
2.2. SeparationofHCYandHTL
2.2. Separation of HCY and HTL
Since HCY and HTL react in a rather identical way with OPA/NaOH under flow
Since HCY and HTL react in a rather identical way with OPA/NaOH under flow
conditions,simultaneousanalysiscanbecarriedoutonlyafterasimpleandyeteffective
conditions, simultaneous analysis can be carried out only after a simple and yet effective
separationstep.
separation step.
GNPshavebeenevolvedasviablealternativesforbothsamplepreparationandsensor
GNPs have been evolved as viable alternatives for both sample preparation and sen-
development in bioanalysis [23–25]. Fluorosurfactant-capped GNPs (FSN-GNPs) have
sor development in bioanalysis [23–25]. Fluorosurfactant-capped GNPs (FSN-GNPs) have
proventoofferenhancedspecificityand,mostimportantly,stabilityunderhighsalinity
proven to offer enhanced specificity and, most importantly, stability under high salinity
conditions[26]. FSNinteractswiththenanoparticlesthroughthehydrophilicendofthe
conditions [26]. FSN interacts with the nanoparticles through the hydrophilic end of the
molecule,whilethehydrophobicchainsremaindispersedinthesolution[27,28]. Small
molecule, while the hydrophobic chains remain dispersed in the solution [27,28]. Small
molecules,suchasHCY,canpenetratetheFSNlayerandinteractwiththeGNPs,causing
molecules, such as HCY, can penetrate the FSN layer and interact with the GNPs, causing
aggregation. Larger molecules are repelled through strong hydrophobic interactions,
aggregation. Larger molecules are repelled through strong hydrophobic interactions, of-
offeringuniqueselectivityproperties.
fering unique selectivity properties.
Onthisbasis,HuangandChenghavereportedquantitativeremovalofHCY(ca. 98%)
On this basis, Huang and Cheng have reported quantitative removal of HCY (ca.
usingtheFSN-GNP-basedproceduredescribedinSection3.4[14]. Toverifytheirfindings,
ar9t8ifi%ci)a ulsuirning ethmea FtrSixNs-pGiNkePd-bwaistehdH pCroYciendtuhree rdanesgceriobfe2d– 3in0 µSmecotiloLn− 31.4(fi [n1a4l].c oTnoc evnertrifayti othnesir
offi0n.d1–in1g.5s,µ amrtoiflicLi−al1 )uwrineree mparotrciexs sspedikeeidt hwerithd iHreCctYly ino rthfoel lroawngine goft h2e–3s0e pμamraotli oLn−1s (tfeipna.lT choen-
centrations of 0.1–1.5 μmol L−1) were processed either directly or following the separation
experimentalresultsaredepictedinFigure3. Basedontheratiosoftheslopes,ca. 97.1%
step. The experimental results are depicted in Figure 3. Based on the ratios of the slopes,
removalofHCYwasachieved.
ca. 97.1% removal of HCY was achieved.
AsecondseriesofexperimentsconfirmedtheabsenceofinteractionoftheFSN-GNPs
withHAT Lseacotntwd osecroiensc oenf etrxapteiorinmleevnetsl sc,onnafmirmeleyd5 thane dab1s0enµcme oolf Lin−te1.raRcetipoent iotifv tehes eFpSaNr-aGtiNonPs
with HTL at two concentration levels, namely 5 and 10 μmol L−1. Repetitive separation
experimentsresultedinsatisfactoryrecoveriesintherangeof95–108%,bothintheabsence
anedxpinertihmeepnrtes sreenscueltoefdH inC Ysa(t2is0faµcmtoorlyL r−e1c)o(vFeirgiuerse in4) .the range of 95–108%, both in the ab-
sence and in the presence of HCY (20 μmol L−1) (Figure 4).
3
