**4. The application of cellulose-based CSPs in enantioseparation of chiral pesticides**

Chiral HPLC is a good method to separate enantiomers/stereoisomers of chiral pesticides because it facilitates the preparation of single enantiomers for study of enantiomeric bioactivity, toxicology and environmental fate. In recent years, cellulose-based CSPs prepared with different cellulose derivatives and methods resulted in their very broad application for chiral separation of pesticides such as organophosphates [38], organochlorine, triazole, synthetic pyrethroids, acylanilides, imidazolinones, phenoxypropanoic-acid herbicides and related compounds [39].Table 2 summarizes the resolution results of 79 chiral pesticides in current references.

As shown in Table 2, the stereoselective separations of most of chiral pesticides can be achieved on NP-HPLC and some on RP-HPLC using cellulose-based CSPs. The most efficient CSP with the highest chiral recognition ability is CDMPC, available under the commercial names of Chiralcel OD, Chiralcel OD-H, Chiralcel OD-R, Chiralcel OD-RH, Lux Cellulose-1 and Kromasil CelluCoatTM. The coated CDMPC on APS exhibited higher chiral discrimination for most of pesticides than the bonded type available under the commercial names of Chiralpak IB and Chiralpak IC. For example, the resolution factor (Rs) of systemic fungicide-metalaxyl on the coated CDMPC is 4.54 with hexane/IPA (80:20) as the mobile phase, which is significantly higher than that on the bonded CDMPC with an Rs of 0.632 using hexane/IPA (97/3) as the mobile phase.

The Development and Application of Cellulose-Based Stationary Phases

Separation effect\*2

Chromatographic condition\*1

mL/min; CD 230nm

0.8mL/min; UV 254nm

0.8mL/min; UV 254nm

0.8mL/min; UV 230nm

0.6); 0.3mL/min; UV

35C, 1.0 mL/min, UV

35C, 1.0 mL/min, UV

0.5mL/min; UV 230nm

0.5mL/min; UV 230nm

0.8mL/min; UV 230nm

0.5mL/min; UV 230nm

0.9mL/min; UV 220nm

0.5mL/min; UV 228nm

0.5mL/min; UV 270 nm

(84/16); 0.5mL/min; UV

1.0 mL/min;

Chiralcel OJ heptane/ethanol(99.4/

203nm

254 nm

254 nm

Chiralcel OD-H Hexane/IPA(90/10),

CDMPC hexane/IPA (90/10);

CDMPC hexane/IPA(99/1);

CDMPC hexane/IPA (99/1);

CDMPC hexane/IPA (95/5);

CDMPC hexane/n-butyl alcohol

280 nm

mL/min; UV 230nm

mL/min;

CMPC hexane/ethanol(99/1); 1.0 mL/min;

Chiralcel OJ-H hexane/IPA(100/10);

8 chlordane Chiralcel OD hexane; 1.0 mL/min OR:

CDMPC hexane/IPA(99.9/0.1); 1.0

No. Pesticide CSP or Chiral

7 carfentrazoneethyl

13 alpha-

14 theta-

15 beta-

18 diclofopmethyl

cypermethrin

cypermethrin

cypermethrin

colum

4 bifenthrin Chiralcel OJ-H hexane/ethanol(98/2); 1.0

5 bioallethrin CDMPC hexane/ethanol(99/1); 1.0

6 bitertanol Chiralcel OD-H hexane/IPA(100/3);

9 crotoxyphos Chiralcel OJ hexane/ethanol(90/ 10);

10 crufomate Chiralcel OD heptane/ethanol(90/10);

11 cycloprothrin Chiralcel OJ-H hexane /IPA(70/30),

12 cypermethrin CDMPC hexane/IPA (90/10);

16 dialifos Chiralcel OJ heptane/ethanol(90/ 10);

17 dichlorprop Chiralcel OJ-H hexane/IPA (90/10);

in Stereoselective Separation of Chiral Pesticides 225

Elution order\*3

[47]

: 1.27 [48]

: 1.39 [49]

Rs: 1.52 [50]

Rs: 3.70 [50]

Rs: 0.52 [51]

TC(trans)+/- CC(cis)+/-

Rs: 1.81 OR: -/+ [54,55]

Rs: 1.1 OR: +/- [55]

Rs: 0.90 OR: -/+ [55]

[56]

[56]

seven peaks [57]

Rs: 1.53 [57]

four peaks [57]

Rs: 3.12 OR: +/- [55]

Rs: 1.34 S/R [59]

[63]

Rs: 11.8 S/R [60-62]

Rs: >1.5 OR: -/+ [58,57]

Reference

[52,53]

The second most efficient CSP in terms of resolution is CTMB available under the commercial names of Chiralcel OJ, Chiralcel OJ-H, Chiralcel OJ-RH, Lux Cellulose-3. It exhibited higher chiral discrimination for some chiral pesticides than CDMPC. For example, the Rs of triazole fungicide-imazalil on Chiralcel OJ-H is 5.21, which is significantly higher than 1.51 obtained on Chiralcel OD-H using the same mobile phase of hexane/IPA (100/3) and the same flow rate of 0.8 mL/min on NP-HPLC. The combination of CDMPC and CTMB on NP-HPLC and RP-HPLC can separate most chiral pesticides listed in Table 2.

The separations on NP-HPLC were better than those on RP-HPLC for most chiral pesticides. The cellulose-based CSPs on NP-HPLC can generally give better resolution and yield a larger amount of a single enantiomer in one injection. However, its application is limited because some racemates are polar and difficult to dissolve in the weak polar solvents used as mobile phase on NP-HPLC. For this reason, the amount of racemates loaded on CSPs cannot be increased. The separation on RP-HPLC is sometimes less effective than on NP-HPLC, but it can use more methanol, acetonitrile or water in the mobile phase and can thus significantly improve the solubility of some racemates that will not readily dissolve in the hexane, heptane and isopropanol used in NP-HPLC. This is very helpful to prepare optically pure enantiomer of polar chiral compounds and obtain more enantiomer in a shorter time. Additionally, the use of HPLC in the reversed phase can easily be connected in tandem with mass spectrometry, which makes it possible to establish more sensitive and more efficient analytical methods for enantioselective studies of chiral pesticides [40-42].



using hexane/IPA (97/3) as the mobile phase.

No. Pesticide CSP or Chiral

colum

1 amiprophos Chiralcel OJ-H hexane/IPA(100/5);

2 benalaxyl CDMPC hexane/IPA(97/3); 1.0

3 benzex Chiralce1 OJ hexane/IPA(91/9); 0.5

ChiralpakIB; Chiralcel OJ-H

As shown in Table 2, the stereoselective separations of most of chiral pesticides can be achieved on NP-HPLC and some on RP-HPLC using cellulose-based CSPs. The most efficient CSP with the highest chiral recognition ability is CDMPC, available under the commercial names of Chiralcel OD, Chiralcel OD-H, Chiralcel OD-R, Chiralcel OD-RH, Lux Cellulose-1 and Kromasil CelluCoatTM. The coated CDMPC on APS exhibited higher chiral discrimination for most of pesticides than the bonded type available under the commercial names of Chiralpak IB and Chiralpak IC. For example, the resolution factor (Rs) of systemic fungicide-metalaxyl on the coated CDMPC is 4.54 with hexane/IPA (80:20) as the mobile phase, which is significantly higher than that on the bonded CDMPC with an Rs of 0.632

The second most efficient CSP in terms of resolution is CTMB available under the commercial names of Chiralcel OJ, Chiralcel OJ-H, Chiralcel OJ-RH, Lux Cellulose-3. It exhibited higher chiral discrimination for some chiral pesticides than CDMPC. For example, the Rs of triazole fungicide-imazalil on Chiralcel OJ-H is 5.21, which is significantly higher than 1.51 obtained on Chiralcel OD-H using the same mobile phase of hexane/IPA (100/3) and the same flow rate of 0.8 mL/min on NP-HPLC. The combination of CDMPC and CTMB

The separations on NP-HPLC were better than those on RP-HPLC for most chiral pesticides. The cellulose-based CSPs on NP-HPLC can generally give better resolution and yield a larger amount of a single enantiomer in one injection. However, its application is limited because some racemates are polar and difficult to dissolve in the weak polar solvents used as mobile phase on NP-HPLC. For this reason, the amount of racemates loaded on CSPs cannot be increased. The separation on RP-HPLC is sometimes less effective than on NP-HPLC, but it can use more methanol, acetonitrile or water in the mobile phase and can thus significantly improve the solubility of some racemates that will not readily dissolve in the hexane, heptane and isopropanol used in NP-HPLC. This is very helpful to prepare optically pure enantiomer of polar chiral compounds and obtain more enantiomer in a shorter time. Additionally, the use of HPLC in the reversed phase can easily be connected in tandem with mass spectrometry, which makes it possible to establish more sensitive and more efficient

on NP-HPLC and RP-HPLC can separate most chiral pesticides listed in Table 2.

analytical methods for enantioselective studies of chiral pesticides [40-42].

Chiralcel OD-H hexane/IPA(100/5);

mL/min

Chromatographic condition\*1

0.8mL/min; UV 254nm

0.8mL/min; UV 254nm

hexane( IPA or ethanol); 0.5 mL/min; UV 220 nm;

mL/min; UV 22nm

Separation effect\*2

Elution order\*3

Rs: 1.65 [43]


Rs>1.5 R-(-) /S-(+) [44]

[45]

[46]

Reference


The Development and Application of Cellulose-Based Stationary Phases

Separation effect\*2

Rs: 4.79, 3.96

Chromatographic condition\*1

hexane/isobutanol (95/5); 1.0 mL/min; UV

0.9); 0.5mL/min; UV

0.8mL/min; UV 230nm

MET/water(70/30); 1.0 mL/min; UV 220nm

0.5mL/min; UV 290nm

MET/water (80/20); 0.8mL/min; UV 265nm

ACN/water (50/50); 0.8mL/min; UV 230nm

0.8mL/min; UV 201nm

0.8mL/min; UV 230nm

mL/min; UV 230nm

1.2mL/min; UV 230nm

(89/11); 0.5mL/min; UV

0.5mL/min; UV 251nm

mL/min; UV 254nm

mL/min; UV 230nm

hexance/IPA(95/5); 0.6mL/min; UV 230nm

0.5mL/min; UV 230nm

MET/water(70/30); 1.0 mL/min; UV 220nm

0.3mL/min; UV 210 nm

mL/min;

CDMPC hexane/IPA(95/5); 1.0

270nm

CHIRALPAK IC hexane/IPA(90/10); 1.0

CDMPC hexane/ IPA(99/1); 0.5

CDMPC MET/water(80/20);

Lux Cellulose-1 ACN/water(70/30),

CDMPC hexane/ IPA (95/5);

CDMPC hexane/ IPA(97/3);

230nm

203nm

CDMPC hexane/ethanol (93/7);

CDMPC ACN/water(70/30);

No. Pesticide CSP or Chiral

27 fenoxapropethyl

31 flampropmethyl

33 fluazifop-pbutyl

34 fluroxypyrmeptyl

35 flutriafol Chiralcel OD;

colum

25 fenamiphos Chiralcel OJ heptane/ethanol(99.1/

26 fenbuconazole Lux Cellulose-1 ACN/water(90/10),

28 fensulfothion Chiralcel OJ heptane/ethanol(96/4);

29 fenthiaprop CDMP ACN/water (50/50);

30 fipronil Chiralcel OD isooctane/IPA(96/6); 6.0

32 fluazifop-butyl CDMPC hexane/n-butyl alcohol

Chiralcel OD-H; CDMPC

36 tau-fluvalinate Chiralcel OJ hexane/ethanol(90/10);

in Stereoselective Separation of Chiral Pesticides 227

Elution order\*3

Rs: 7.05 OR: +/- [64,80]

Rs: 1.08 OR: +/- [55]

: 1.00 [81]

Rs: 1.83 [61]

Rs: 1.01 OR: +/- [66]

Rs: 1.53 OR: -/+ [66]

Rs: 1.21 OR: -/+ [55]

Rs: 1.53 OR: -/+ [66]

[82]

[83]

Rs: 1.59 R/S [84]

Rs: 2.55 S/R [61]

Rs: 3.80 S/R [60]

[85]

Rs: 1.31 [86]

Rs: 1.07 OR: +/- [66]

Rs: 1.59 [87]

Rs: 1.99, 1.39

Rs: 1.37 OR: -/+ [71,50, 64]

OR: -/+ [75]

OR: +/- [75]

Reference


colum

CDMPC coated on TiO2/SiO2

19 diclofop acid Chiralcel OJ-H hexane/IPA/acetic acid

20 difenoconazole Chiralcel OJ hexance/ethanol(90/10);

Chiralcel OD

Chiralcel OJ; Chiralcel OJ-H

22 dioxabenzofos Chiralcel OJ hexane/IPA(95/5); 1.0

24 ethofumesate CDMPC hexane/IPA (98/2); 1.0

CDMPC

21 diniconazole CDMPC;

23 epoxiconazole Lux Cellulose-1;

Chromatographic condition\*1

(98/2); 1.0 mL/min; UV

hexane/IPA(65/35), 1.0

mL/min; UV 230 nm

0.5mL/min; UV 254 nm

(84/16); 0.5mL/min; UV

(84/16); 0.5mL/min; UV

(90/10/0.2); 0.5mL/min;

(90/10/0.2); 0.5 mL/min;

0.6 mL/min; UV 230nm.

0.6mL/min; UV 253nm

hexane/IPA(100/3); 1.0 mL/min; UV 225nm

MET/water(80/20); 1.0 mL/min; UV 220nm

mL/min; UV 220nm

mL/min; UV 220nm

ACN/water(50/50), MET/water(80/20); 1.0 mL/min; UV 220nm

mL/min; UV 230nm

hexane/IPA (93/7); 1.0 mL/min; UV 230nm

mL/min; UV 225nm

CDMPC hexane/isobutanol

230nm

mL/min

CDMPC ACN/water (50/50); 0.8

CTMB hexane/IPA (50/50);

CTB hexane/n-butyl alcohol

280 nm

280 nm

CD 282nm

UV 230 nm

hexane/n-butyl alcohol(98/2); 1.0 mL/min; UV 220nm

Chiralcel OJ-H hexane/IPA/acetic acid

Chiralcel OD hexane/IPA(90/10);

Lux Cellulose-1 ACN/water(70/30),

Chiralcel OD hexane/IPA(99.5/0.5); 1.0

Chiralcel OD-H hexane/IPA(100/5); 1.0

CTPC hexane/n-butyl alcohol

Separation effect\*2

Elution order\*3

Rs: 6.15 OR: -/+ [64,39,65]

Rs: 1.50 [19]

Rs: 1.53 OR: -/+ [66]

Rs: 1.68 R/S [67,68,63]

Rs: 5.49 R/S [69,70]

Rs: 3.79 OR: +/-/+/- [71]

Rs: 1.17 OR: +/- 71

Rs: 1.53 OR: +/- [72,61]

: 1.20 R(-)/S(+) [73,50]

: 1.14 R(-)/S(+) [73,74]

Rs: 1.56 OR: -/+ [76]

Rs: 1.42 OR: -/+ [76]

Rs: 6.34 [77]

: 1.58 OR; +/- [78,79]

OR: -/+ [75,66]

OR: −/+ [75,66]

Rs: 2.31, 2.62

Rs: 2.04, 1.62

Reference

[63]

[63]

[70]

No. Pesticide CSP or Chiral


The Development and Application of Cellulose-Based Stationary Phases

Separation effect\*2

Chromatographic condition\*1

hexane/IPA(85/15) 0.8mL/min; UV 310 nm

0.6); 0.3mL/min; UV

0.8mL/min; UV 280nm

0.8mL/min; UV 280nm

0.8mL/min; UV 230nm

mL/min; UV 220nm

mL/min; UV 230nm

0.8mL/min; UV 265nm

mL/min; UV 236 nm

mL/min, UV 236 nm

mL/min; UV 220nm

0.9mL/min; UV 220nm

mL/min; UV 220nm

mL/min; UV 210nm

mL/min; UV 230nm

0.8mL/min; UV 230nm

hexane/IPA(65/35); 1.0

0.6 mL/min, UV 236 nm

Chiralcel OJ hexane/ IPA/acetic acid (84.6/15.4/0.1); 0.8mL/min; UV 275nm

225nm

mL/min;

Chiralcel OJ heptane/ethanol(99.4/

201nm

Chiralcel OJ-H hexane/IPA(100/1);

Chiralcel OD-H hexane/IPA(100/1);

CDMPC ACN/water(70/30);

CDMPC MET/water(75/25);

Chiralpak IC hexane/ CH2Cl2/TFA (65/35/0.1)

Chiralecl OD Hexane/IPA(95/5), 0.5

Chiralecl OJ hexane; ethanol ( 95/5);

Chiralecl OJ Hexane/IPA( 90/10); 0.4

Chiralcel OJ hexane/IPA(97/3); 1.0

CDMPC hexane/IPA(99/1); 1.0

mL/min

CDMPC ACN/water(70/30);

No. Pesticide CSP or Chiral

46 indoxacarb Lux cellulose-1;

49 isofenphosmethyl

52 lambda-

cyhalothrin

colum

Chiralcel OD

47 isocarbophos CDMPC hexane/IPA(98/2); UV

48 isofenphos Chiralcel OG heptane/IPA(98/2); 1.0

50 iso-malathion Chiralcel OJ hexane/IPA(97/3); 1.0

51 lactofen CDMPC hexane/IPA(99/1); 1.0

53 malaoxon Chiralcel OJ hexane/IPA(96/4); 1.0

54 malathion Chiralcel OJ heptane/ethanol(90/ 10);

55 metalaxyl CDMPC hexane/IPA(80:20); 1.0

CDMPC coated on TiO2/SiO2

in Stereoselective Separation of Chiral Pesticides 229

Elution order\*3

Rs: 2.42 OR: -/+ [64,51,95]

Rs: 1.1 OR: +/- [55]

Rs: 1.11 OR: +/- [55]

Rs: 1.59 [81]

Rs: 1.73 [43]

: 1 [81]

[66]

Rs: 1.07 OR: -/+ [66]

Rs: 8.11 [96]

Rs: 4.06 R/S

CD: -/+ [97]

CD: -/+ [97]

CD: -/+/+/- [97]

[98]

OR: +/-

Rs: 4.11 OR: +/- [55]

Rs: 3.35 OR: +/- [98]

Rs: 1.44 OR: +/- [65]

: 1.0 [81]

Rs: 2.97 [19]

Rs: 4.54 [26,99]

Rs: 1.87 OR: +/- [64, 39]

OR: -/+ [93,94]

[90]

Reference


colum

37 fonofos Chiralcel OJ heptane/ethanol(99.5/0.5

Chiralcel OD

40 imazalil Chiralcel OD-H hexane/IPA(100/3);

42 imazapic Chiralcel OJ hexane/ alcohol/TFA

43 imazapyr Chiralcel OJ hexane/ IPA/acetic acid

Chiralcel OD-R ACN/ PBS

44 imazaquin Chiralcel OJ-H Hexane/IPA/Acetic

45 imazethapyr Chiralcel OJ hexane/ethanol/ acetic

41 imazamox Chiralcel OD-R ACN/ PBS

Chromatographic condition\*1

Chiralcel OG hexane/IPA Rs: <0.91 Chiralcel OD-R MET/water; UV 210 nm Rs: <0.91

Chiralcel OJ-H hexane/IPA(100/10);

Chiralcel OD-H hexane/IPA(100/0.5);

Chiralcel OD hexane; 1.0 mL/min; UV 215nm

CDMPC hexance/ tertiary butanol

270nm

Chiralcel OD-H ACN/MET(98/2);

Lux Cellulose-1 ACN/water(90/10),

Chiralcel OJ-H hexane/IPA(100/3);

Chiralcel OD ACN/water(50/50);

mL/min

UV 254nm

mL/min

(84.6/15.4/0.1); 0.8mL/min; UV 275nm

Chiralcel OJ hexane(0.1%TFA)/IPA(6 0/40

);1.0 mL/min; UV 202nm

0.8mL/min; UV 254nm

0.8mL/min; UV 254nm

hexance/IPA(91/9); 0.5mL/min; UV 270.9nm

(95/5); 0.5mL/min; UV

0.5mL/min; UV 254nm

MET/water(80/20); 1.0 mL/min; UV 220nm

0.8mL/min; UV 220nm

0.8mL/min; UV 220nm

0.8mL/min; UV 240nm

buffer(50mM)(20/80); 1.0

(75/25/0.1); 1.0 mL/min;

acid(84.6/15.4/0.1); 0.8 mL/min; UV 275 nm

buffer(50mM)(20/80); 1.0

acid (75/25/0.5); 1.0 mL/min; UV 250nm Separation effect\*2

Elution order\*3

Rs: 2.1 OR: +/- [55,54]

Rs: 9.58 [43]


[53]

Rs: 2.30 [88]

Rs: 1.51 [89]

Rs: 1.51 [50]

Rs: 5.21 [50]

Rs: 0.91 OR: −/+ [66]

[39]

Rs: 0.89 [90]

Rs: 2.44 [90]

OR: +/- [90]

OR: +/- [91]

CD: +/- [91,39]

OR: +/- [92]

OR: +/- [75]

Rs: 2.25, 2.12

Rs: 4.79 OR: +/- [61,66,

Reference

71,72]

No. Pesticide CSP or Chiral

38 heptachlor epoxide

39 hexaconazole CDMPC;


The Development and Application of Cellulose-Based Stationary Phases

Separation effect\*2

Rs: 7.58, 2.29

Chromatographic condition\*1

ACN/water(50/50), MET/water(90/10); 1.0 mL/min; UV 220nm

0.3mL/min; UV 210 nm

.6mL/min; UV 230nm

0.8mL/min; UV 230nm

Chiralcel OD-R MET/water; UV 210 nm Rs: <0.91

CDMPC ACN/water(70/30);

UV 210nm

); 1.0 mL/min; UV

0.8mL/min; UV 230nm

mL/min; UV 230nm.

15C; 1.0 mL/min; UV

0.5mL/min; UV 332nm

dichloride(450/2/8); 1.0 mL/min; UV 290 nm

mL/min; UV 254nm

hexane/IPA(98/2); 1.0 mL/min; UV 220nm

hexane/IPA(100/10); 0.8mL/min; UV 225nm

0.6mL/min; UV 269.8nm

0.5mL/min; UV 254nm

mL/min; UV 220nm

mL/min; UV 225nm

hexane/IPA(99/1); 1.0 mL/min; UV 230nm

Chiralcel OJ heptane/ethanol(99.5/0.5

202nm

Chiralcel OJ hexane; 0.8mL/min; UV 230nm

202nm

Chiralcel OJ-H hexane/MET/methylene

CDMPC hexane/NPA (91/9);

CTPC hexane/IPA(91/9);

Chiralcel OD-H ACN/IPA(70/30);

Chiralcel OD hexane/IPA(100/5); 1.0

CDMPC ACN/water(70/30);

No. Pesticide CSP or Chiral

64 penconazole Lux Cellulose-1

colum

Chiralcel OD-H

65 permethrin Chiralcel OJ hexane/ethanol(95/15);

66 phenthoate Chiralcel OJ hexane/IPA(90/10);

67 profenofos CDMPC hexane/IPA(99.5/0.5);

68 propiconazole Chiralcel OD hexance/IPA(90/10); 0.6

69 prothiophos Chiralcel OJ heptane/ethanol(98/2);

71 pyraclofos Chiralcel OD hexane/IPA(90/10); 1.0

Chiralcel OD

CTMB

Chiralcel OJ-H;

73 tetraconazole Lux Cellulose-1 ACN/water(90/10); 1.0

Chiralcel OD

70 quizalofop-Pethyl

72 tebuconazole CDMPC;

74 triadimefon CDMPC;

in Stereoselective Separation of Chiral Pesticides 231

Elution order\*3

Rs: 1.47 [87]

: 1.0 [81]

Rs: 1.35 OR: +/- [64]

Rs: 3.52 OR: +/- [55]

Rs: 1.12 OR: +/- [54]

: 1.0 [81]

Rs: 1.6 OR: +/- [55]

Rs: 1.7 R/S [61]

S/R [110]

OR: +/-/+/- [71]

OR: -/+ 109

71]

Rs: 1.63 OR: -/+ [50,61, 64,

Rs: 5.64 [50, 61]

Rs: 1.16 [61]

Rs: 0.67 [89]

Rs: 1.39 OR: +/- [75]

: 1.20 R(-)/S(+) [73]

Rs: 1.47 OR: -/+ [64, 71]

Rs: 2.95/ 2.72/ 1.04 OR: -/+ [75,89]

OR: -/+ [109]

Reference


colum

56 metalaxyl acid CDMPC hexane/IPA/TFA(70/30/0

59 metolachlor Chiralcel OD-H hexane/diethyl ether

60 myclobutanil CDMPC hexane/IPA(73/26);

Lux Cellulose-1; CDMPC; Chiralcel OD

61 naproanilide CDMPC hexane/IPA(80/20); 1.0

Chiralcel OD-H; Chiralcel OJ-H

62 napropamide Chiralpak OJ-H hexane/IPA(80/20);

63 paclobutrazol CDMPC ACN/water(40/60); 0.8

Chiralcel OD; CDMPC

Chromatographic condition\*1

mL/min; CD 236 nm

.1%); 1.0 mL/min

mL/min; UV 230nm

); 0.8mL/min; UV 200nm

0.8mL/min; UV 230nm

(91/9); 0.8 mL/min; UV

0.5mL/min; UV 221.5nm

0.5mL/min; UV 221.5nm

hexane; 1.0 mL/min; UV

0.5mL/min; 40C; UV

mL/min; UV 230nm.

mL/min; UV 225nm.

hexance/IPA(100/2); 0.8 mL/min; UV 225nm.

ACN/water(90/10), MET/water(90/10); 1.0 mL/min; UV 220nm

or 0.5mL/min

254 nm

Bonded-CTB hexane; 1.0 mL/min; UV 254 nm

220nm

OJ hexance/IPA(100/10); 0.8

Bonded CDMPC MET/water(50/50) Rs: 0.506 [101] Bonded CDMPC ACN/water(80/20) Rs: 0.766 [101] Bonded CDMPC hexane/IPA(97/3) Rs: 0.632 [101]

ChiracelOJ-H hexane/IPA(90:10); 0.5

Bonded CDMPC hexane/tertbutyl alcohol (95/5)

CDMPC hexane/IPA(99/1); 1.0 mL/min;

CDMPC hexane/IPA(90/10); 1.0

Chiralcel OD heptane/ethanol(90/ 10); 1.0 mL/min;

Chiralcel OJ heptane/ethanol(93.5/6.5

230 nm

CTPC hexane/IPA(73/26);

CDMPC ACN/water(70/30);

Separation effect\*2

Elution order\*3

S/R [100]

Rs: 0.918 [101]

Rs: 1.96 CD(-)/(+) [102]

at 228 nm; CD(+)/(-) at 280nm

Rs: 1.54 OR: +/- [65,103]

Rs: 1.7 OR: +/- [55]

Rs: 1.56 OR: +/- [55]

: 1.0 [81]

[104]

Rs: 13.3 [61]

Rs: 1.54 [50]

Rs: 1.91 [105]

OR: +/- [106]

OR: -/+ [106]

[107]

Rs: 1.93 OR: +/− [108]

Rs: 1.83 [50, 61]

Rs: 4.05 [50]

OR: +/- [75, 66]

Rs: 5.10, 4.91

Rs: 1.85 CD (-)/(+)

Reference

[102,26]

No. Pesticide CSP or Chiral

57 metalaxyl

58 methamidophos

intermediate


The Development and Application of Cellulose-Based Stationary Phases

Cellulose derivatives have high chiral recognition abilities for racemates and have already become a very popular and useful source material for CSPs. Cellulose-based CSPs can be prepared by coating or bonding cellulose derivatives on decorative silica gel or other supports with various preparation methods. The coated CSPs exhibite higher discrimination abilities for chiral pesticides and are more popular than the bonded CSPs. However, the bonded CSPs can tolerate broader solvent ranges, including THF and CHCl3, which cannot be used on coated CSPs as mobile phases because they have strong dissolution abilities that can dammage or destroy them. Coated CDMPC and CTMB had the broadest application in the stereoselective separations of chiral pesticides. For most pesticides, better separations were obtained on NP-HPLC than on RP-HPLC. However, RP-HPLC can improve the amount of racemates loaded on CSPs as it allows the use of more polar solvents to enhance the solubility of racemates in mobile phases. Additionally, it can be easily connected in tandem with MS, allowing for the development of more sensitive methods for analysis of enantiomers/stereoisomers. The cellulose-based CSPs on NP-HPLC and RP-HPLC provide very powerful tools to prepare individual enantiomers and study the activity, toxicity and

Jing Qiu, Shouhui Dai, Tingting Chai, Wenwen Yang, Shuming Yang and Hualin Zhao *Institute of Quality Standards & Testing Technology for Agro-Products, Chinese Academy of* 

The financial support from National Natural Science Foundation of China (Project number

[1] Okamoto Y, Ikai T. Chiral HPLC for efficient resolution of enantiomers. Chem Soc Rev

[2] Wang T, Chen YW. Application and comparison of derivatized cellulose and amylase chiral stationary phases for the separation of enantiomers of pharmaceutical compounds by high-performance liquid chromatography. J Chromatogr A

[3] Okamoto Y, Kaida Y. Resolution by high-performance liquid chromatography using polysaccharide carbamates and benzoates as chiral stationary phases. J Chromatogr A

*Key Laboratory of Agri-Food Quality and Safety, Ministry of Agriculture, Beijing, China* 

21177156 and 20907073) for this work is hereby gratefully acknowledged.

**5. Conclusion** 

environmental fates of chiral pesticides.

*Agricultural Sciences, Beijing, China* 

**Acknowledgement** 

2008;37:2593-2608.

1999;855:411-421.

1994;666: 403-419.

**6. References** 

**Author details** 

in Stereoselective Separation of Chiral Pesticides 233

\*1 ACN, MET and IPA means acetronitrile, methanol and isopropanol respectively.

\*2 and Rs means the separation factor and the resolution facotr respectively.

\*3 CD and OR means signals obtained from circular dichrism detector and optical rotation detector respectively.

**Table 2.** Summary of resolution results of chiral pesticides on cellulose-based CSPs
