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Accurately Analyze Metal-Sensitive Compounds with Restek’s New Inert LC Columns

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Our new inert LC column technology helps labs improve their analysis of metal-sensitive compounds. A premium inert coating applied to the stainless-steel surface of our LC columns reduces nonspecific binding of chelating analytes, enabling sensitive analysis and smooth integration of peaks. Combined with Restek’s selective stationary phases, these new inert LC columns are ideal for the analysis of metal-sensitive compounds, such as organophosphorus pesticides and mycotoxins.

Restek’s inert LC columns can provide four key benefits:

  • Improved peak shape without passivation or mobile phase additives.
  • Increased response and analyte recovery, allowing lower detection limits.
  • High accuracy and throughput with less variability.
  • Less time-consuming conditioning and complicated passivation required.

Exceptional Inertness Brings Exceptional Performance

Analyzing compounds that have nonspecific adsorption (NSA) or nonspecific binding (NSB) to metal surfaces in LC columns has historically been a challenge. Poor peak shape and sensitivity are key indicators that polar, usually acidic compounds are interacting with the metal surfaces in the column, causing poor data quality. Our premium inert column technology is designed to eliminate NSA and NSB of active analytes to the column hardware, giving analysts greater confidence in their data when working with metal-sensitive analytes.

An Extensive Product Line to Meet Your Unique Needs

Restek’s inert LC column technology is available in various column types to accommodate a wide range of applications and testing methodologies. Our inert columns are now available for the following phase types: Raptor Biphenyl, Raptor C18, Raptor ARC-18, Force Biphenyl, and Force C18. The following columns are recommended for these specific applications:

Inert LC Column Application
Raptor Inert ARC-18 Pesticides
Raptor Inert Biphenyl Mycotoxins
Force Inert C18 Methylmalonic acid
Raptor Inert C18 Veterinary Drugs

 

Pesticides

Pesticide panels benefit from the use of inert LC columns as they contain a wide variety of compounds. Phosphorylated, acidic, polar compounds, and/or metal chelating species, such as organophosphate pesticides, are reactive to the metal surfaces inside of the analytical column. Our new inert LC columns solve that problem easily to improve the overall performance of your pesticide panel.

Figure 1: Our new Raptor inert ARC-18 columns offer increased sensitivity, recoveries, and lower detection limits without any column preconditioning.

cgarm-img
LC_EV0596
PeakstR (min)Precursor IonProduct Ion 1Product Ion 2Peak AreaPeak Height
1.Methamidophos1.33142.094.0125.1428941105189
2.Acephate1.55184.0143.048.9300642104729
3.Omethoate1.72214.0125.0182.9892008337690
4.Monocrotophos2.21224.1127.0193.121581078425
5.Dicrotophos2.35238.1112.172.0404916159292
6.Dimethoate2.52230.0125.0199.0807805342939
7.Trichlorfon2.53257.0108.9220.817394263266
8.Vamidothion2.54288.0146.0118.01333829547308
9.Mevinphos isomer 12.55241.9126.9192.9311274129961
10.Mevinphos isomer 22.76241.9126.9192.97403029802
11.Carbaryl3.18202.1145.0127.03967111924
12.Isocarbophos3.52291.1231.1121.13329411941
13.Dimethomorph isomer 13.96388.2300.9165.1511766172977
14.Dimethomorph isomer 24.13388.2300.9165.1877031328826
15.Temephos5.70467.1124.9418.916431064751
ColumnRaptor Inert ARC-18 (cat.# 9314A12-T)
Dimensions:100 mm x 2.1 mm ID
Particle Size:2.7 µm
Pore Size:90 Å
Temp.:50 °C
Standard/SampleLC multiresidue pesticide standard #1 (cat.# 31972)
Diluent:Water, 0.1% formic acid
Conc.:1 ng/mL
Inj. Vol.:5 µL
Mobile Phase
A:Water, 2 mM ammonium formate, 0.1% formic acid
B:Methanol, 2 mM ammonium formate, 0.1% formic acid
Time (min)Flow (mL/min)%A%B
0.000.4955
2.000.44060
4.000.42575
6.000.40100
7.500.40100
7.510.4955
9.000.4955
DetectorShimadzu LCMS-8060
Ion Mode:ESI+
Mode:MRM
InstrumentShimadzu Nexera X2

 

Figure 2: Compared to a conventional, stainless-steel column, our new Raptor inert ARC-18 columns provide exceptional analyte recoveries.

cgarm-img
LC_EV0591

 

Figure 3: Peak area and peak height are greatly improved for the analysis of pesticides.

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LC_EV0593

 

Table I: Restek's new inert columns showed up to 2x improvement in peak area and peak height over stainless-steel columns in this analysis of pesticides.

Compound Peak Area Peak Height
Stainless Steel Inert Areas Ratio (Inert/Stainless Steel) Stainless Steel Inert Height Ratio (Inert/Stainless Steel)
Methamidophos 254969 428941 1.68 52553 105189 2.00
Acephate 168776 300642 1.78 58418 104729 1.79
Omethoate 579502 892008 1.54 216157 337690 1.56
Monocrotophos 140095 215810 1.54 51402 78425 1.53
Dicrotophos 340978 404916 1.19 135380 159292 1.18
Dimethoate 461156 807805 1.75 188746 342939 1.82
Trichlorfon 84233 173942 2.07 34793 63266 1.82
Vamidothion 913264 1333829 1.46 354311 547308 1.54
Mevinphos isomer 1 213632 311274 1.46 82105 129961 1.58
Mevinphos isomer 2 56093 74030  1.32 29070 29802 1.03 
Carbaryl 43590 39671 0.91 14563 11924 0.82
Isocarbophos 21587 33294 1.54 9062 11941 1.32
Dimethomorph isomer 1 462425 511766 1.11 166990 172977 1.04
Dimethomorph isomer 2 896109 877031 0.98  311657 328826 1.06 
Temephos 98793 164310 1.66 35383 64751 1.83

 

Mycotoxins

Mycotoxins analysis can be challenging and often requires a great deal of column conditioning and equilibration to achieve acceptable peaks. This is due to the reactive nature of the compounds, which contain acidic, polar, or otherwise metal chelating groups. Our new inert column hardware, combined with our stationary phases, helps simplify methods and improve the response and peak shape of these compounds.

Figure 4: Achieve excellent peak shape without additional acid passivation or mobile phase additives when analyzing mycotoxins with our new Raptor inert biphenyl columns.

cgarm-img
LC_FS0552
PeakstR (min)Conc.
(ng/mL)
Precursor IonProduct Ion Peak AreaPeak Height
1.Nivalenol 0.8810295.1137.1418264495
2.Deoxynivalenol1.2510297.2231.017346281906
3.Fusarenon-X1.9210355.1137.17668121790
4.15-Acetyldeoxynivalenol3.0810339.2137.131369517570
5.3-Acetyldeoxynivalenol3.1410339.2213.122613296396
6.Tenuazonic acid4.1110198.1125.047828197658
7.Altenuene4.6010293.2257.11138502059699
8.Alternariol5.2710259.0185.1732721302192
9.Ergosine5.2810548.4208.14866209366601
10.Citrinin5.4610251.2233.110078809828889
11.Ergosinine5.4610548.4208.14967348740527
12.Fumonisin B15.4810722.5352.31228782415567
13.Diacetoxyscirpenol5.6210384.2247.1681391208825
14.Ergotamine5.7110582.4223.24930039274155
15.Ergocornine5.8510562.4268.23870257732744
16.Ergotaminine5.9610582.4223.24621199237991
17.HT-26.1310447.2345.115221323765
18.Ergocryptine6.1910576.4268.252220411360838
19.Fumonisin B36.2310706.4336.21433023444421
20.Ergocristine6.4410610.4223.21955624450058
21.Fumonisin B26.5910706.4336.21517193869822
22.Tentoxin6.6210415.2312.2951752131906
23.α-Zearalenol6.9110303.1285.130224702420
24.Ergocorninine6.9310562.4268.270402914389283
25.Aflatoxin G26.9710331.2189.02628245274353
26.T-27.0910489.2387.1565351394735
27.Ergocryptinine7.1810576.4268.277897216765348
28.Ergocristinine7.4010610.4223.2158305332975663
29.Aflatoxin G17.4510329.1199.73043896102959
30.Zearalenone7.5910319.2283.137162927455
31.Alternariol monomethylether7.6210273.0199.131024640689
32.Aflatoxin B27.6310315.1287.02956485724754
33.Aflatoxin B18.0210313.2241.12235204425821
34.Ochratoxin A8.2510404.1239.01900604411953
ColumnRaptor Inert Biphenyl (cat.# 9309A12-T)
Dimensions:100 mm x 2.1 mm ID
Particle Size:2.7 µm
Pore Size:90 Å
Temp.:60 °C
Standard/SampleAflatoxins standard (cat.# 34121)
Ochratoxin A standard (cat.# 34122)
Diluent:50:50 Water:methanol
Conc.:10 ng/mL
Inj. Vol.:5 µL
Mobile Phase
A:Water, 0.05% formic acid
B:Methanol, 0.05% formic acid
Time (min)Flow (mL/min)%A%B
0.000.47525
5.000.45050
9.000.40100
9.010.47525
11.00.47525
Max Pressure:440 bar
DetectorWaters Xevo TQ-S
Ion Mode:ESI+
Mode:MRM
InstrumentWaters ACQUITY UPLC I-Class
Notes

 

Figure 5: In this analysis of fumonisins, our new Raptor inert biphenyl columns achieve a dramatic increase in peak area compared to conventional, stainless-steel columns.

cgarm-img
LC_FS0554

 

Figure 6: Peak area and peak height are greatly improved for the analysis of fumonisins.

cgarm-img
LC_FS0556

 

Table II: In this analysis of mycotoxins, our new inert columns can provide an up to 10x increase in peak height over conventional columns.

Compound Peak Area Peak Height
Stainless Steel Inert Areas Ratio (Inert/Stainless Steel) Stainless Steel Inert Height Ratio (Inert/Stainless Steel)
Fumonisin B1 32578 122878 3.77 399544 2415567 6.05
Fumonisin B2 23427 151719 6.48 383130 3869822 10.10
Fumonisin B3 29864 143302 4.80 472279 3444421 7.29
Ergocristine 171197 195562 1.14 3865898 4450058 1.15
Ergocristinine 1393116 1583053 1.14 29212317 32975663 1.13
Ergotamine 433635 493003 1.14 8149518 9274156 1.14
Ergotaminine 397370 462119 1.16 7885403 9237991 1.17
Ergocryptine 446481 522204 1.17 9671753 11360839 1.17
Ergocryptinine 658788 778972 1.18 13680420 16765348 1.23
Ergocornine 370509 387025 1.04 7248981 7732744 1.07
Ergocorninine 590167 704029 1.19 12052359 14389283 1.19
Ergosine 445243 486620 1.09 8630932 9366602 1.09
Ergosinine 439026 496734 1.13 7820785 8740527 1.12
T-2 43286 56535 1.31 1046233 1394735 1.33
HT-2 10183 15221 1.49 216703 323765 1.49
Tentoxin 70973 95175 1.34 1577164 2131907 1.35
Ochratoxin 173686 190060 1.09 4039682 4411953 1.09
Diacetoxyscirpenol 47850 68139 1.42 846403 1208826 1.43
Fusarenone X 3865 7668 1.98 60409 121790 2.02
15-acetyl-DON 17055 31369 1.84 269862 517570 1.92
3-acetyldeoxyvinalenol 13353 22613 1.69 179204 296396 1.65
Aflatoxin G2 171597 262824 1.53 3429501 5274354 1.54
Aflatoxin G1 224058 304389 1.36 4607959 6102959 1.32
ZON 25617 37162 1.45 656915 927455 1.41
Aflatoxin B2 159389 295648 1.85 3462489 5724754 1.65
Aflatoxin B1 265935 223520 0.84 5335576 4425821 0.83
Alpha-zearalenol 16202 30224 1.87 382092 702420 1.84
Deoxynivalenol 6935 17346 2.50 117927 281906 2.39
Nivalenol 1790 4182 2.34 25276 64495 2.55
Altenuene 63224 113850 1.80 1187958 2059700 1.73
Alternariol monomethyl ether 19537 31024 1.59 428922 640689 1.49
Alternariol 48204 73272 1.52 837410 1302192 1.56
Citrinin 499900 1007880 2.02 5031182 9828890 1.95
Tenuazonic acid 21503 47828 2.22 89293 197658 2.21

Methylmalonic Acid

The analysis of methylmalonic acid is an important test for clinical laboratories in identifying a Vitamin B12 deficiency. When utilizing our inert hardware in testing for methylmalonic acid, a 40% improvement in sensitivity was achieved compared to regular hardware. A significant increase in methylmalonic acid peak area and peak height is shown for the inert hardware in Figure 7, below. 

Figure 7: The Force Inert C18 column led to significant increases in sensitivity of methylmalonic acid compared to a conventional, stainless-steel column.

cgarm-img
LC_EX0524
PeaksPrecursor IonProduct Ion
1.MMA116.9772.97
Column
Temp.:35 °C
Standard/Sample
Diluent:50:50 Water:methanol
Conc.:100 ng/mL
Inj. Vol.:5 µL
Mobile Phase
A:Water, 0.5% formic acid
B:Methanol, 0.5% formic acid
Time (min)Flow (mL/min)%A%B
0.000.7955
0.500.7955
3.000.7595
3.010.7955
5.000.7955
Max Pressure:275 bar
DetectorWaters Xevo TQ Absolute
Ion Source:Waters Zspray ESI
Ion Mode:ESI-
Mode:MRM
InstrumentWaters ACQUITY Premier
NotesColumns are:
• Force C18 (cat.# 963431E)
• Force Inert C18 (cat.# 963431E-T)

Veterinary Drugs

The identification of veterinary drugs in food samples, particularly in meats, fish, and eggs, is an important test for ensuring safe food products according to the guidelines outlined by the FDA and the EU. In the analysis of 10 common vet drugs, shown in Figure 8 below, dramatic increases in analyte responses were identified when utilizing the inert column compared to traditional, stainless-steel column.

Figure 8: Utilizing the Raptor Inert C18 column led to significant increases in analyte response for vet drugs compared to a conventional, stainless-steel column.

cgarm-img
LC_FS0557
PeaksPrecursor IonProduct Ion
1.Lincomycin407.00359.00
2.Norfloxacin320.00276.00
3.Tulathromycin A806.60577.00
4.Cefazolin455.00323.00
5.Difloxacin400.00356.00
6.Pirlimycin411.00363.00
7.Gamithromycin777.00619.00
8.Erythromycin734.00576.00
9.Virginiamycin M1526.00508.00
10.Cloxacillin436.00277.05
Column
Temp.:35 °C
Standard/Sample
Diluent:50:50 Methanol:water
Conc.:10 ng/mL
Inj. Vol.:2 µL
Mobile Phase
A:Water, 0.1% formic acid
B:Acetonitrile, 0.1% formic acid
Time (min)Flow (mL/min)%A%B
0.000.49010
4.500.46535
7.000.44555
7.010.49010
9.000.49010
Max Pressure:283 bar
DetectorShimadzu 8060 MS/MS
Ion Source:Electrospray
Ion Mode:ESI+
Mode:MRM
InstrumentShimadzu Nexera X2
NotesColumns are:
• Raptor C18 (cat.# (9304A12)
• Raptor Inert C18 (cat.# (9304A12-T)

Exceptional Inertness Meets Exceptional Stationary Phases

We’re introducing our inert LC column technology on three column types: Raptor Biphenyl, Raptor ARC-18, and Force Biphenyl. These new columns help bring the benefits of inert column technology to labs specializing in small molecule LC-MS/MS workflows.

 

Raptor LC Columns

Raptor LC Columns

Raptor LC columns combine the speed of 2.7 µm SPP with the resolution of Ultra Selective Liquid Chromatography (USLC) technology, improving separations and speeding up analysis times with standard HPLC instruments. When speed is your goal, Restek recommends the Raptor line of LC columns.

Learn more at www.restek.com/Raptor

Raptor Inert Biphenyl

This industry-leading Biphenyl is our most popular LC stationary phase. It is particularly adept at separating compounds that are hard to resolve or that elute early on C18 and other phenyl chemistries.

Raptor Inert C18

This traditional end-capped C18 offers the highest hydrophobic retention of any Raptor phase, and it is compatible with a wide range of mobile phases from moderately acidic to neutral (pH 2–8). Whether for food safety or environmental or bioanalytical analyses, this phase offers consistently excellent data quality in less time across myriad reversed-phase applications, matrices, and compound classes.

Raptor Inert ARC-18

The Raptor ARC-18 column features a well-balanced retention profile without the drawbacks of using an ordinary C18 in the harsh, acidic mobile phases needed for mass spectrometry. Even after extended use in these low-pH (≤ 2.0) conditions, the sterically protected ARC-18 offers consistent retention, peak shape, and response for charged bases, neutral acids, small polar compounds, and more.

 

Force LC Columns

Force fully porous particle (FPP) LC columns are designed and manufactured to handle high-pressure, high-stress conditions. They’re long-lasting, reproducible, and premium quality—backed by our 100% Pure Satisfaction guarantee. When you need greater retention and sharper peaks, Force LC columns are ready to be put to work.

Learn more at www.restek.com/Force

Force Inert Biphenyl

The Force Inert Biphenyl column separates compounds that other phenyl and C18 chemistries can’t. They allow the use of simple, MS-friendly mobile phases and are ideal for when you need to increase retention of hydrophilic aromatics.

Force Inert C18

The general-purpose Restek Force Inert C18 is a conventional monomeric octadecylsilane column suitable for analyses of a wide range of compounds from acidic through slightly basic. 

Exceptional Inertness for Your Analysis

As chromatographers, we understand the importance of having confidence in your data. Whether you’re analyzing pesticides, mycotoxins, or any analysis containing metal-sensitive compounds, these new LC columns provide the accuracy, throughput, and performance your lab needs.

Contact your local Restek representative today at www.restek.com/contact-us to pair the benefits of our inert technology with your analysis.

GNSS4155D-UNV