Evaluation of Five Core Shell Columns Based on BothSeparation Behavior and Physical Property
www.chromanik.co.jp

Norikazu Nagae1), Tomoyasu Tsukamoto1), Vinay Gaitonde1), Anders Grahn2), Ralf Jutvik2)
1) ChromaNik Technologies Inc., 6-3-1 Namiyoke, Minato-ku, Osaka, Japan3) Biotech AB, Box 133, 439 23, Onsala, Sweden

www.biotech-sweden.com

Abstract

A column packed with core shell particles has been widely used on HPLC and UHPLC, because it showed not only excellent column efficiency butalso lower back pressure than sub-2 um column. More than 10 kinds of core shell column are available in the market. It is said that two types ofcore shell silica particle are used. One is a mono-layer structure as a porous silica layer like a core shell silica manufactured by Advanced Materials
Technology and another is a multi-layer structure like that manufactured by Phenomenex.
In this study, a separation behavior and physical property of Kinetex C18, Accucore C18, PoroShell C18 EC, Ascentis Express C18 and SunShell C18
were evaluated. Retention factor, hydrogen bonding capacity, hydrophobicity and steric selectivity were measured using Tanaka method. Not only
peak shape of neutral, acidic and basic compounds but also loading capacity of amitriptyline under neutral and acidic conditions were alsomeasured. Furthermore stability under acidic pH1 and basic pH10 conditions was evaluated. Regarding physical property, carbon loading of eachC18 packing material, and specific surface area, pore volume, pore diameter of each core shell silica which was deleted alkyl chains by sintering at600 degree Celsius for 8 hours were measured. As a result, the big difference was recognized among 5 kinds of core shell C18 for separation
behavior, stability and physical property. This difference is considered to be due to each manufacturing method and bonding technique as well as
fully porous silica C18s. SunShell C18 showed the largest retention factor and the highest stability though its carbon loading is not the highest,
while Kinetex C18 showed the lowest retention factor, the lowest carbon loading and the lowest specific surface area.

Physical Property

31423123

1

0

2

7

523

k6=9.7

6

4

5

SunShell C18
21.8 MPa 4468Company S C18
22.2 MPa76101214k6=10.4

161820220.48

1.54

1.20

8.0

133 (150)b0.278

8.20 (9)b8.5 (8)b135 (130)b0.414

12.3 (12)bAccucore C18

8.8 (9)b130 (130)b0.273

8.39 (8)bKinetex C18

4.9(12 effective)b102(200 effective)b0.237

9.25 (10)bCompany T C18

0.35

1.56

1.50

0.42

1.57

1.25

Company S C18

0.44

1.60

1.31

10

SunShell C18

0.39

1.60

1.46

924

Retention time/min

Number/%Company P C183Company T C182132Company A C18

132Company S C18123123456754189Company T C182Company AC1821Company S C18

TF=2.04
2101

TF=1.2123467

Retention time/min

1011122Particle diameter/μm

TF=1.47

1

TF=1.45

TF=3.2132Company P C18
32

TF=1.86

Company T C18

1121Company A C18

233Company S C18

1
TF=1.46

04

8

Stability under pH1 and 10 Conditions

1389102Column:
Company P C18, 2.6 mm 150 x 4.6 mm
Company T C18, 2.6 mm 150 x 4.6 mmCompany A C18, 2.7 mm 150 x 4.6 mm
Company S C18, 2.7 mm 150 x 4.6 mm
SunShell C18, 2.6 mm 150 x 4.6 mm
Mobile phase: CH3CN/0.1% H3PO4=2/98
Flow rate: 1.0 mL/min
Temperature: 40 ºC
Detection: UV@210nm
Sample: 1 = Formic acid
2 = Acetic acid
3 = Propionic Acid

Relative retention/%

Column:Company P C18, 2.6 mm 150 x 4.6 mm
Company T C18, 2.6 mm 150 x 4.6 mm
Company A C18, 2.7 mm 150 x 4.6 mm
Company S C18, 2.7 mm 150 x 4.6 mm
SunShell C18, 2.6 mm 150 x 4.6 mm
Mobile phase: CH3CN/20mM H3PO4=10/90
Flow rate: 1.0 mL/min
Temperature: 40 ºC
Detection: UV@250nm
Sample: 1 = 8-Quinolinol (Oxine)
2 = Caffeine

Comparison of Formic Acid
10.1

1T C18(core shell)

10S C18(core shell)

TF=4.38012

34567Retention time/min

8910

Sample: 1=Uracil, 2=Propranolol,
3= Nortriptyline, 4=Amitriptyline

16000

TF=2.0914000

100 times

10000

SunShell C18

8000

Sunniest C18 3um

Company A C18

T C18(core shell)

Company P C186000

Company T C18

TF=3.21Company S C18

400000.0010.010.1110012345678910Retention time/min

Sample weight/μg

Mobile phase: Acetonitrile/10mM ammonium acetate pH6.8=(40:60)

SunShell C18

5P C18(core shell)

TF=3.210.01

14000

Durable test condition
Column size: 50 x 2.1 mm
Mobile phase: CH3CN/1.0% TFA, pH1=10/90
Flow rate: 0.4 mL/min
Temperature: 80 ºC80
▲60▲

SunShell C18
Company S C18

40TF=1.20

Company T C18
Company P C1820pH1, 80oC

Company A C18020406080

100120

SunShell C18(core shell)

10000

Sunshell C18
Company A C18Company P C18
Company T C18
Company S C18

8000
6000

SunShell C18
Company S C1860

Company P C18
Company T C18

40

Measurement condition
Column size: 50 x 2.1 mm
Mobile phase: CH3OH/H2O=70/30
Flow rate: 0.4 mL/min
Temperature: 40 ºC
Sample: 1 = Butylbenzene

Company A C18

20

pH10, 50oC

00

1,000 2,000 3,000 4,000 5,000 6,000

T C18(core shell)

TF=3.24

0.01

0.1

1

S C18(core shell)

100123

4

56789

10

Retention time/min

Sample: 1=Uracil, 2=Propranolol,
3= Nortriptyline, 4=Amitriptyline

Mobile phase: Acetonitrile/0.1% formic acid=(30:70)

480

P C18(core shell)

TF=2.61

TF=2.73

Sample weight/μg

4.5

100

30 times

4000

00.001

Time/hDurable test condition
Column size: 50 x 2.1 mm
Mobile phase:
CH3OH/20mM Sodium borate/10mM
NaOH=30/21/49 (pH10)
Flow rate: 0.4 mL/min
Temperature: 50 ºC

A C18(core shell)

TF=1.89

2000

Measurement condition
Column size: 50 x 2.1 mm
Mobile phase: CH3CN/H2O=60/40
Flow rate: 0.4 mL/min
Temperature: 40 ºC
Sample: 1 = Uracil, 2 = Butylbenzene

0Relative plate of butylbenzene/%

Company P C18

TF=2.07

TF=2.43c. Median particle size

22

1Sunniest
C18 3mm(fully porous)

Company S C18

4000*Measured using Beckman Coulter Multisizer 3 after C18 materials were sintered at600 degree Celsius for 8 hours. The measured value of each sintered core shell silica
is considered to be different from that of the original core shell silica.

Metal Chelating Compound

TF=3.94

TF=1.25Company T C18

2000

Comparison of Oxine,

1Company P C18

12000

3100

TF=1.24

Sunniest C18 3um

6000

12000

Retention time/min

18000

A C18(core shell)

TF=1.42Company A C18

Theoretical plate was calculated by 5σ method
using peak width at 4.4% of peak height.

SunShell C18

1060Column:
Company P C18, 2.6 mm 150 x 4.6 mm
Company T C18, 2.6 mm 150 x 4.6 mm
Company A C18, 2.7 mm 150 x 4.6 mm
Company S C18, 2.7 mm 150 x 4.6 mm
SunShell C18, 2.6 mm 150 x 4.6 mm
Mobile phase: CH3OH/H2O=30/70
Flow rate: 1.0 mL/min
Temperature: 40 ºC
Detection: UV@250nm
Sample: 1 = Uracil
2 = Pyridine
3 = Phenol

SunShell C1800.00112100 times

10000

2000

23

112000

SunSehll C18 (2.54 μm)c
Ascentic Express C18 (2.52 μm)c
Accucore C18 (2.53 μm)c
Kinetex C18 (2.34 μm)c
PoroShell C18 (2.34 μm)c

7SunShell C18(core shell)

TF=1.18

14000

Sample weight/μg8Comparison of Pyridine

16000

a. Measured after C18 materials were sintered at 600 degree Celsius for 8hours. The measured value of each sintered core shell silica is considered
to be smaller than that of the original core shell silica.
b. Value written in each brochure or literatureCompany A C18

Mobile phase: Acetonitrile/20mM phosphate buffer pH7.0=(60:40)
Column dimension: 150 x 4.6 mm, Flow rate: 1.0 mL/min, Temp.: 40oC

8.34 (9)b

PoroShell C18 EC(Amylbenzene/Butylbenzene) (Triphenylene/o-Terphenyl)

Company P C180.261

Ascentis Express C18

Hydrogen bonding Hydrophobicity Steric selectivity(Caffeine/Phenol)

125 (150)b

Theoretical plate142

7.3 (7)bLoading Capacity of Amitriptyline
Pore diameter a(nm)USP tailing factor

211 3

SunShell C18

Company P C18
26.1 MPa

Specific surface Pore volume aarea a (m2/g)(mL)

Theoretical plate

Column:Company P C18, 2.6 mm 150 x 4.6 mm (26.1 MPa)
6Company T C18, 2.6 mm 150 x 4.6 mm (22.7 MPa)
Company A C18, 2.7 mm 150 x 4.6 mm (30.6 MPa)
Company S C18, 2.7 mm 150 x 4.6 mm (22.2 MPa)75
SunShell C18, 2.6 mm 150 x 4.6 mm (21.8 MPa)k6=7.4 Company T C18
Mobile phase: CH3OH/H2O=75/25
622.7 MPa
Flow rate: 1.0 mL/min
Temperature: 40 ºC
7Sample: 1 = Uracil, 2 = Caffeine, 3 = Phenol,
5Company A C18
k6=9.04 = Butylbenzene, 5 = o-Terphenyl,
4630.6 MPa
6 = Amylbenzene, 7 = Triphenylene
7k6=5.4

5Carbonloading (%)

Theoretical plate

Comparison of Standard Samples

3.5
3
2.5

USP tailing factor

Company S C18
Company T C18

3.6

Company P C18

2.9

Company A C18
SunShell C18

2.4

7 times

21.8

1.5

1.3

10.001

40.01

0.1

5 min

61Sample weight/μg
In the case of using acetonitrile /0.1% formic acid as a mobile phase, amitriptyline peak shows
more tailing because a loading capacity decreases in an acidic, low-ionic-strength mobile phase.

Elution volume/mLAcidiccondition pH 1

Basic condition pH range written in each
pH 10
brochureSunShell C18◎◎

1.5 - 10

Ascentis Express C18○○2- 9PoroShell C18 EC△△2-9Accucore C18△△1 - 11Kinetex C18△△

1.5 - 10

3Column name
1. Company P C18, 2.6 mm: Kinetex c18
2. Company T C18, 2.6 mm: Accucore C18
3. Company A C18, 2.7 mm: PoroShell C18 EC
4. Company S C18, 2.7 mm: Ascentis Express C18
5. SunShell C18, 2.6 mm

SunShell C18
23456Retention time/minConclusion

SummaryPressurea

Retentionb

SunShell C18

◎21.8

10.4

Pyridine Oxine Formic acid Point◎◎◎

12Ascentis Express C18

◎22.2

9.7

△△×5

PoroShell C18 EC

×30.6

9.0

◎

△

◎

7

Accucore C18◎22.7

7.4××△

4Kinetex C18△26.1

5.4×◎◎

7a. Mobile phase, methanol:water=75:25, 40 oC, 1mL/min 150 x 4.6mm
b. Retention factor of amylbenzene◎: 3 point, ○: 2 point, △: 1 point, ×: 0 point

A big difference concerning retention, residual silanol groups, metal impurity, loading capacity
and stability among core shell C18s was confirmed as well as fully porous C18s
SunShell showed the longest retention, the lowest pressure, the most symmetrical peak andthe highest stability.
Measurements of physical property are not same as a value to be shown in a brochure and aliterature in some cases.