Usability of a core shell column using high performance liquid
chromatograph for a routine analysis
Tomoyasu Tsukamoto1), Norikazu Nagae1), Scott Silver2)
1) ChromaNik Technologies Inc., 6-3-1 Namiyoke, Minato-ku, Osaka, Japan
2) Innovations United, 300 East 57th Street, Suite 11J New York, NY 10022 USA

Appling for HPLC

Abstract
Superficially porous particle (core shell particle) has been available as an alternative to using
sub-2 μm particle for HPLC or UHPLC. Core shell particles are composed of a 1.2 to 1.9 μm
solid core encircled a 0.25 μm to 0.5 μm porous layer. Especially a 2.6 μm core shell particle
shows a half back pressure and the almost same efficiency to compare with sub-2 μm particle
because of a large particle and reducing mass transfer due to a thin porous silica layer. In thisstudy, a 2.6 μm core shell silica with a non-porous core approximately 1.6 μm in diameter anda superficially porous layer of 0.5 μm was used as a based material. A core shell silica bondedwith C18 and end-capped was evaluated for a routine analysis, which is done using
conventional 5 μm particle column sized 150 or 250 x 4.6 mm i.d. A core shell C18 column
sized 100 x 4.6 mm and a conventional C18 column sized 250 x 4.6 mm were compared foran analysis of analgesics using Hitachi LaChrom ELITE HPLC under a isocratic mode. Bothcolumns showed the same efficiency and an analysis time by a core shell C18 columns
decreased to one third to compare with a conventional C18 column without changing ofconditions except for a column, a same instrument, a same flow rate, a same mobile phase. Incase of gradient separation of catechins, the almost same result was obtained as well as
under a isocratic mode.

HPLC

312

11/3 or 1/2 of analysis time

54N(4)=18,444

543254

Brand G C18, 3 μm 150 x 4.6 mm

32

1N(4)=19,313

Brand F C18, 5 μm 250 x 4.6 mm

N(4)=20,287

SunShell C18, 2.6 μm 100 x 4.6 mm
02468

1014

1216

18

200

1224

22

N(4)=20,287
N(4)=20,287

32

154

3Retention time/min

4UHPLC56Sample:

N(4)=24,124

1.0 mL/min

N(4)=22,424

1.8 mL/min

Analysisi time decreases to 1/6 to comparewith a 5mm column sized 250x4.6mm.

Core shell vs Sub-2 μm fully porous

Column:Brand F C18, 5 μm 250 x 4.6 mm
Brand G C18, 3 μm 150 x 4.6 mm
SunShell C18, 2.6 μm 100 x 4.6 mm
Mobile phase:
CH3CN/20mM Phosphoric acid = 45/55
Flow rate: 1.0 mL/min,1.8 mL/min at the lowest chromatogram
Temperature: 25 ºC
Pressure: 9.5 MPa for Brand F C18 5 μm
14.5 MPa for Brand G C18 3 μm
13.4 MPa for SunShell C18 2.6 μmDetection: UV@230 nm
1 = Benzydamine
2 = Ketoprofen
3 = Naproxen
4 = Indomethacin
5 = Ibuprofen

HPLC: Hitachi LaChrom ELITE(using 0.25 mm i.d. tubing)
UHPLC: Jasco X-LC

Retention time/min

Figure. 7 Examples of transfer (isocratic separation)

16
Plate height (μm)

SunShell column kept the low plate heightunder the low flow late conditions.
But fully porous column couldn‘t keep

Column: C18, 50 x 2.1 mm
Mobile phase:
Acetonitrile/water=(60/40)
Sample : Naphthalene

20

Sunshell 2.6 μm 40℃

4

Brand E sub-2 μm 40 ℃
(Fully porous type)3Column:
Brand H C18, 5 μm 150 x 4.6 mm
SunShell C18, 2.6 μm 75 x 4.6 mm
Mobile phase:A) 0.1% Phosphoric acidB) CH3CN
Gradient program for Brand G C18

7621

Sunshell 2.6 μm 25 ℃

124Brand H C18, 5 μm 150 x 4.6 mm

HPLC

89

5SunShell C18, 2.6 μm 75 x 4.6 mm
6 7213Time%B

1/2 of Analysis time895804246810Retention time/min

B term decrease

41214621300.5
Flow rate mL /min

101241875896879Retention time/min

Figure. 1 Comparison of plate height

4UHPLC

Fully porous silica

Comparing between SunShell and sub-2μm column • • •SunShell (core shell column) wasCore shell• Similar theoretical plate• lower plate height under low
flow rate conditions(because core interferes withdiffusion in the column direction)

Flow rate (mL/min)
Diffusion of solute is blocked bycore without pores

31650

B term decreases

17389

50123452022

HPLC: Hitachi LaChrom ELITE(using 0.25 mm i.d. tubing)UHPLC: Jasco X-LC

6Figure. 8 Examples of transfer (gradient separation)

Appling for HPLC 2Column: SunShell C18, 2.6 μm 100 x 4.6 mm
Mobile phase: CH3CN/H2O=60/40
Flow rate: 1.8 mL/min
Temperature: ambient
Instrumental: X-LC, LC2000Plus (JASCO)

154

1

1SunShell C18402

46

1 = Uracil, 2 = Caffeine, 3 =Brand A Sample:
Phenol,6

4 = Butylbenzene, 5 = o-Terphenyl,
6 = Amylbenzene, 7 = Triphenylene

576Durable 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 ºC8060

pH180oC

40

Brand K

20SunShell C180204060

80

100120Time (h)Figure 4. Stability under acidic pH condition

8 10 12 14 16 18 20 22 24
Retention time/min

100

Hydrogen bonding
Hydrophobicity
Steric selectivity(Caffeine/Phenol) (Amylbenzene/(Triphenylene/Butylbenzene)
o-Terphenyl)
Brand K

0.48

1.54

1.20

Brand A

0.44

1.60

1.31

SunShell C18

0.40

1.59

1.47

Figure 3. Comparison of standard samples

8060

pH1040oC

40

Brand K
Brand A

20

SunShell C1800

1,000

2,000
3,000
4,000
Elution volume(mL)

5,000

Durable 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
Measurement condition
Column Size: 50 x 2.1 mm
Mobile phase:
CH3OH/H2O=70/30
Flow rate: 0.4 mL/min
Temperature: 40 ºC
6,000 Sample: 1 = Butylbenzene

Figure 5. Stability under basic pH condition

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
16000

Theoretical Plate

14000

SunShell C18(core shell)

12000
100 times

10000
8000
6000
4000

Brand K
Brand ASunShell C18
Sunniest C18 3um

Sunniest
C18 3mm(fully porous)
Brand K C18(core shell)

2000
0
0.001

0.01

0.1

1

Brand A C18(core shell)

10Sample weight/mg

01

2

3

4

56
7
Retention time/min

8910

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

Theoretical plate was calculated by 5σ method using peakwidth at 4.4% of peak height.
4.4%Figure 6. Loading capacity of amitriptyline

UHPLC 3Comparing between SunShell andother brand columns • • •SunShell has• Different selectivity• High stability under bothacidic and basic pH conditions• Good peak shape foramitriptyline• High Loading capacity

HPLC pump＋UHPLC detector
12Column: SunShell C18, 2.6 μm 100 x 4.6 mm
Mobile phase: CH3CN/H2O=60/40
Flow rate: 1.8 mL/min
Temperature: ambient
Pump: Shimadzu LC-6A, Detector: X-LC3075UV42342Measurement condition
Column size: 50 x 2.1 mm
Mobile phase: CH3CN/H2O=60/40Flow rate: 0.4 mL/min
Temperature: 40 ºC
Sample: Butylbenzene

Brand A0

Different Selectivity
from other brandcolumns
Relative plate of butylbenzene(%)

2 3Mobile phase: CH3OH/H2O=75/25
Flow rate: 1.0 mL/min
Temperature: 40 ºC7

2 3

Relative retention (%)

Brand K
64100

Column:Brand K C18, 2.6 μm 150 x 4.6 mm
Brand A C18, 2.7 μm 150 x 4.6 mm
SunShell C18, 2.6 μm 150 x 4.6 mm

0 min 7.5 min 10 min
2%25%
25%

Flow rate: 1.0 mL/min,
Temperature: 25 ºC
Detection: UV@250 nm
Sample: Oolong tea
1 = Gallocatechin, 2 = Epigallocatechin,
3 = Catechin, 4 = Caffeine, 5 = Epicatechin,
6 = Epigallocatechin gallate, 7 = Gallocatechin gallate,
8 = Epicatechin gallate, 9 = Catechin gallate

375Time%B

24

Retention time/min

1

About SunShell

62Figure. 2 Reason for decreasing B term

2 3
10 min 15 min 20 min
2%
25%
25%

for SunShell C18HPLC

UHPLC

Theoretical plate(1)

16835

16900

Theoretical plate(2)

26013

26107

Theoretical plate(3)

24548

24505

Theoretical plate(4)22823

227914HPLC

1

Theoretical plate(1)16944

Theoretical plate(2)25727

Theoretical plate(3)24933

Theoretical plate(4)23211

Figure. 9 Comparing between UHPLC and HPLC pump with Detector for UHPLCRegarding a core shell column, there was no difference between a system combining
HPLC pump and UHPC detector and UHPLC system.
It is unnecessary for a core shell column to use UHPLC pump.
A point of note is that a core shell column should be used under smaller void volume
conditions to get higher theoretical plate on HPLC.

Conclusions
The 100 × 4.6 sized SunShell column could achieve the same separation tocompare with the 250 × 4.6 sized 5 μm fully porous column under isocraticmode.
An analysis time by a core shell C18 column decreased to one third or half
comparing with a conventional C18 columns without changing of analyticalconditions.
In gradient separation of catechins, the good result was obtained as well as
under isocratic mode.
In case of a core shell column, HPLC with a detector for UHPLC is enough for
100% performance.