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NUCLEOSIL® CHIRAL-1
NUCLEOSIL® CHIRAL-2
NUCLEOSIL® CHIRAL-3

Silica-based phases for HPLC enantiomer separation

Features

NUCLEOSIL® CHIRAL-1
for enantiomer separation based on ligand exchange · USP L32

Base material NUCLEOSIL® silica, particle size 5 μm, pore size 120 Å,
chiral selector L-hydroxyproline – Cu2+ complexes

Principal interaction mode:
formation of ternary mixed-ligand complexes with Cu(II) ions
Differences in the stability of the diastereomeric complexes cause chromatographic separation.

Eluent in column 0.5 mM copper sulfate solution

Recommended application: enantiomers with two polar functional groups with the correct spacing such as α-amino acids, α-hydroxycarboxylic acids (e.g.,lactic acid), N-alkyl-α-amino acids etc.

NUCLEOSIL® CHIRAL-2 / NUCLEOSIL® CHIRAL-3
for enantiomer separation in organic eluent systems · USP L36

Base material NUCLEOSIL® silica, particle size 5 μm, pore size 100 Å,
chiral selector for NUCLEOSIL® CHIRAL-2: N-(3,5-dinitrobenzoyl)-D-phenylglycine, for NUCLEOSIL®CHIRAL-3 the optical antipode of the CHIRAL-2 phase, "brush type" phases

Principle interaction modes:
charge-transfer interactions, hydrogen bonds, dipole-dipole interactions and steric effects

Eluent in column n-heptane – 2-propanol – TFAA (100:0.05:0.05)

Recommended application: analysis of stereoisomers such as separation of enantiomers and diastereomers, control of optical purity of plant protectives (pesticides, e.g., propionic acid derived herbicides), pharmaceuticals etc. and for product control in chiral organic syntheses

For control of the optical purity of a substance, the two columns NUCLEOSIL® CHIRAL-2 and NUCLEOSIL® CHIRAL-3 allow to select conditions such that the minor enantiomer, which is present as an impurity, is eluted before the main peak. Thus, overlapping peaks are avoided. This makes an exact quantification of the impurity much easier.

For more applications click here.

NUCLEOSIL Chiral-1典型應(yīng)用
如果樣品中有兩個合適空間位置的極性基團，能夠與銅離子產(chǎn)生整合作用，CHIRAL-1就應(yīng)該能夠成功地進行手性拆分。例如α-氨基酸（氨基和羧基），α-羥基羧酸（乳酸等），N-烴基α-氨基酸，以及小分子量的手性化合物。D,L-phenylalanine, D,L-pyenylglycine,  D,L-proline, D,L-threonine, D,L-valine.

 

CU2+濃度

增加CU2+濃度可以縮短樣品的保留時間。典型的CU2+濃度應(yīng)該在0.2m M-3m M之間；如下圖NUCLEOSIL CHIRAL-1在分離（D,L）-methionine蛋氨酸時，CU2+濃度的提高，分離度相應(yīng)下降。

有機改性劑
加入有機溶劑（如甲醇：乙腈）可以縮短樣品的保留時間，提高出峰對稱性。

溫度
提高溫度可以相應(yīng)提高柱效，縮短樣品的保留時間，建議一般使用溫度60℃，zui高的柱壓不超過140bar。如下圖NUCLEOSIL CHIRAL-1在分離D,L-alanine丙氨酸時，較低的溫度，可以提高樣品的分離度。

NUCLEOSIL CHIRAL-2鍵合相
   N-(3,5-二硝基苯酰)-D-苯基甘氨酸化學(xué)鍵合Nucleosil球形硅膠，5um保存流動液；正乙烷：異丙醇：三fuyisuan=100:0.5:0.5

NUCLEOSIL CHIRAL-3鍵合相
   N-(3,5-二硝基苯酰)-D-苯基甘氨酸化學(xué)鍵合Nucleosil球形硅膠，5um保存流動液；正乙烷：異丙醇：三fuyisuan=100:0.5:0.5

D,L-supidimide的手性拆分

色譜柱：NUCLEOSIL CHIRAL-2 250×4mm
流動相：四氫呋喃：正辛烷=10:3
流  速：1.0毫升/分鐘
檢測器：UV 220nm

Ordering information

Length 250 mm

EC guard columns*

CC guard column**

EC analytical columns       

NUCLEOSIL® CHIRAL-1

4 mm ID

720081.40 (1/pack)

721188.30 (1/pack)

721455.40 (1/pack)

NUCLEOSIL® CHIRAL-2

4 mm ID

720088.40 (1/pack)

721190.30 (1/pack)

721458.40 (3/pack)

NUCLEOSIL® CHIRAL-3

4 mm ID

720350.40 (1/pack)

721190.30 (1/pack)

721458.40 (3/pack)

* EC 4/3 guard column cartridges are used for EC columns of 4 mm ID with the Column Protection System guard column holder (REF 718966).
** CC 8/4 guard column cartridges are used for EC columns of 4 mm ID with guard column adapter EC (REF 721359).
Guard column cartridges for NUCLEOSIL® CHIRAL-2 and CHIRAL-3 are identical.