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Dr.Maisch phases
Reprosil
Reprosil-Pur
Reprosil-Pur Basic
Reprosil-Gold
Reprosil 80
Reprosil 70/100/300
Reprosil-Saphir
Reprosil-Chiral
Reprosil-Fluosil
SEC / GPC
Reprosil-DIBS+ADS
Reprospher
Reprobond
ReproShell
Repro-Gel (sugars)
Repropak
Stability
Gold-Turbo (1,5 µm)
OPA/FMOC/PAH/Pesticid
Equisil
FS-Nano columns
U-HPLC
MODcol + Multipacker
Outstanding
Ultrasep ES
Fluofix
ReproSil Chiral


Comparison of ReproSil Chiral NR/AM/OM

       
 

Reprosil Chiral-AM / OM / NR

Reprosil Chiral-AM  and Reprosil Chiral-OM  are new Polysaccharide chiral stationary phases. The chiral selectors are Amylose-Tris-(3,5-dimethylphenyl)-carbamate for Chiral-AM  or  Cellulose-Tris-(3,5-dimethylphenyl)-carbamate for Chiral-OM. The selectors are bound to a 5 µm ultrapure silica with 1000 A° pores.
Dr. Maisch company offers them  in 2 different CPS versions: Reprosil Chiral-AM  and Chiral-OM are  designed for separations in normal phase mode, Reprosil Chiral-AM-RP and Chiral-OM-RP for separations in reversed phase mode.
Both  Reprosil Chiral-AM and Chiral-OM columns  have a very broad generality and are able to separate neural, acidic and basic racemates. Nearly each 2. known racemic compound can be separated.
Eluents:
In Normal phase mode typical eluents are hexane / IPA or heptane / IPA mixtures.
Basic samples: To prevent peak tailing of  basic compounds please add 0.1 – 0.5 % Diethylamine or Triethylamine. Acidic samples: To prevent peak tailing of acidic compounds please add 0.1 – 0.5 % TFA or acetic acid.
In Reversed phase mode typical eluents are Acetonitrile / Water  mixtures. You can use also MeOH or Ethanol instead of Acetonitrile. The water content must be below 85 %.
For basic compounds please use 0,5 – 1 N Perchlorate or 0.1 % TFA. For acidic compounds please use HClO4 / NaClO4 buffers together with ACN .

Attention:
Please never use with Reprosil Chiral-AM and Reprosil Chiral-OM  the following eluents, which may destroy the phase:
Ethers, THF, Dioxane,  Dichlormethane, Chloroform, Ketones, Ethylacetate, DMSO, Dimethylformamide (DMF), Dimethylacetamide and 50-100 % IPA.


 

Applicationes with Reprosil Chiral-OM

 

The most frequently used column dimension is 250 x 4.6 mm with a flow between 0.5  – 2.0 ml/min.

Abscisinic acid:           
Alprenolol:
Atropin:           
Benzoin:
2-Butyl-Phenylcarbamate:
Carbinoxamine:
Carteolol:
Cyclopentolate:           
Flavanone:
Guaifenesine:  
Homatropine:   
Hydroxyzine:   
Ibuprofen:
Ibuprofenpiconol:
Metoprolol:
Perisoxal:        
α-Phenylethanol:
2-Phenylpropionic acid:           
Pindolol:
Practolol:
Propranolol:
Sulconazol:     
trans-Stilbenoxide:
Warfarin:         

Hexane / Isopropanol  (80/20) + 0,1% TFA
Hexane / Isopropanol  (80/20) + 0,1% Diethylamine
Hexane / Isopropanol  (80/20) + 0,1% Diethylamine
Hexane / Isopropanol  (90/10)
Hexane / Isopropanol  (90/10)
Hexane / Isopropanol  (90/10)
Hexane / Isopropanol  (90/10)
Hexane / Isopropanol  (90/10)
Hexane / Isopropanol  (90/10)
Hexane / Isopropanol  (80/20) + 0,1% Diethylamine
Hexane / Isopropanol  (80/20) + 0,1% Diethylamine
Hexane / Isopropanol  (90/10)
Hexane / Isopropanol  (99/1) + 0,1% TFA
Hexane / Isopropanol  (90/10)
Hexane / Isopropanol  (80/20) + 0,1% Diethylamine
Hexane / Isopropanol  (90/10)
Hexane / Isopropanol  (90/10)
Hexane / Isopropanol  (98/2) + 1%  Formic acid
Hexane / Isopropanol  (80/20) + 0,1% Diethylamine
Hexane / Isopropanol  (80/20) + 0,1% Diethylamine
Hexane / Isopropanol  (80/20) + 0,1% Diethylamine
Hexane / Isopropanol  (90/10)
Heptane / Isopropanol  (85/15)
Hexane / Isopropanol  (70/30) + 0,1% TFA

 

 

 

Reprosil Chiral OM-RP

In Reversed phase mode typical eluents are Acetonitrile / Water  mixtures. You can use also MeOH or Ethanol instead of Acetonitrile. The water content must be always below 80 %.
For basic compounds please use 0,5 – 1 N Perchlorate or 0.1 % TFA. For acidic compounds please use HClO4 / NaClO4 buffers together with ACN.

 

Applicationes

Alimemazine : Na-Perchlorate 1N  / ACN (60/40)
Hydroxyzine : Na-Perchlorate 1N / ACN (60/40)
Indapamide : H20 / Acetonitrile (60/40)
Phenylbutyric acid: Na-Perchlorate-Perchloric acid  0.5N, pH2 / ACN (60/40)
1-Phenoxy-2-Propanol: H20 / Acetonitrile (60/40)
4-Phenyl-2-Butanol: H20 / Acetonitrile (70/30)
Pindolol: Na-Perchlorate: 1N  / ACN (60/40)
Propanolol: Na-Perchlorate: 1N  / ACN (60/40) or: Acetonitrile / 0,1 % TFA (30/70)
Trimipramine: Na-Perchlorate 1N / ACN (60/40)
Verapamil: Na-Perchlorate 1N / ACN (60/40)

 

Comparison of 3 different Chiral columns from Dr. Maisch:

  • Reprosil Chiral-NR, a brush-type phase with p-electron donor- and p-electron acceptor groups, covalently bound to a 100 A°  8 µm silica. Stable in all HPLC eluents. Very high preparative capacity.
  • Reprosil Chiral-OM, a 1000 A° silica phase modified with cellulose-tris(3,5-dimethylphenyl) carbamate.
  • Reprosil Chiral-AM, a 1000 A° silica phase modified with Amylose--tris(3,5-dimethylphenyl) carbamate.

 

Table 1. Chromatographic properties of the neutral racemates.

Eluent: Heptane / IPA (90/10), Flow: 1 ml/min, Column dimension: 250 x 4.6 mm


Column

ReproSil-Chiral-NR

Reprosil Chiral-OM

Reprosil Chiral-AM

Benzoin

a = 2,6
k'1 =2,4
N =7500

a = 1,5
k'1 =2,7
N =6800

a = 1,4
k'1 =5,5
N =14000

1,1-Binaphtol

a = n.s.
k'1 = 1,2
N =

a =1,2
k'1 = 3,7
N = 2600

a = 1,3
k'1 = 10,0
N = 6200

Trans-Stilbenoxide

a = 3,3
k'1 = 0,78
N =  8900

a = 2,3
k'1 = 0,8
N =  8300

a = 3,4
k'1 = 0,79
N =  1300

2,2,2-Trifluoro-1-(9-anthryl)Ethanol

a = 1,2
k'1 = 1,3
N =  6500

a = 3,2
k'1 = 2.0
N =  3900

a = 1,5
k'1 = 2,0
N =  10000

 

Table 2. Chromatographic properties of the basic racemates.

Eluent: Heptane / IPA (90/10) + 0,1 DEA, Flow: 1 ml/min, Column dimension: 250 x 4.6 mm


Column

ReproSil-Chiral-NR

Reprosil Chiral-OM

Reprosil Chiral-AM

Bupivacine

a = 1,5
k'1 =5,7
N = 5800

a = 1,15
k'1 =0,6
N = 4600

 

 

Carbinoxamine

a = 1,2
k'1 = 5.0
N = 400

a =1,4
k'1 = 0,7
N = 7500

a = 1,4
k'1 = 1,3
N = 10000

Clenbuterol

a = 1,4
k'1 = 2,1
N =  3800

a = no separation
k'1 = 0,7
N = 

a = no separation
k'1 = 1,9
N = 

Ketamine

a = 1,1
k'1 =2.0
N =6200

a = 1,2
k'1 =1,1
N = 6500

a = 1,0
k'1 =1,2

Oxamniquine

a = 1,1
k'1 = 10,6
N = 3100

a = 1,1
k'1 =3,8
N =3100

a = 1,2
k'1 =5,6
N = 10400

Oxprenolol

a = 1,3
k'1 = 2,3
N =  3000

a = 6,3
k'1 = 1,9
N =  3200

a = 1,7
k'1 = 1,1
N =  9000

1-(1-Phenyl)-ethylamine

a = no separation
k'1 = 2,2

a = 1,3
k'1 = 1,1
N =  7500

a = no separation
k'1 = 0,5
N = 

Troeger’s base

a = 1,9
k'1 = 1,1
N =  5900

a = 1,3
k'1 = 1,0
N =  6000

a = 1,8
k'1 = 0,8
N =  9000

Table 3. Chromatographic properties of the acidic racemates.

Eluent: Heptane / IPA (90/10) + 0,1 TFA , Flow: 1 ml/min, Column dimension: 250 x 4.6 mm


Column

ReproSil-Chiral-NR

Reprosil Chiral-OM

Reprosil Chiral-AM

CBZ-Alanine (210 nm)

a = 1,3
k'1 = 3,2
N = 5700

a = 2,9
k'1 = 2,0
N = 3100

a = 2,1
k'1 = 3,7
N = 9200

Flurbiprofen

a = 1,3
k'1 = 1.0
N = 6900

a =1,1
k'1 = 0,7
N = 6000

a = 1,7
k'1 = 1,2
N = 11600

Sulindac

a = no separation
k'1 = 3,0

 

 

a = 1,4
k'1 = 1,9
N =  10200

 

Proglumide
Eluent: Heptane/EtOH (9/1)+ 0,1 TFA

 

a = 1,6
k'1 = 4,3
N = 5900

 

a = 2,2
k'1 = 0,7
N =  3800

 

a = 1,8
k'1 = 2,4
N =  5000

Rules of Thumb
for chiral
separation

Reprosil Chiral-NR:
-Needs an Oxygen at or
near  the chiral centre +
an aromatic ring.
-More predictable.
-Inversion of elution   
order possible.
-Very high prep. capacity
-Stable in all HPLC-
eluents.

Reprosil Chiral-OM:
-High versatile chiral
phase.
-No aromatic ring
necessary.
-No inversion of       
elution order possible
-Scale up possible
-Caution: Not stable in 
all eluents.

Reprosil Chiral-AM:
-Highest generality of
all chiral phases.
-No aromatic ring
necessary.
-No inversion of elution
order possible
-Scale up possible
-Caution: Not stable in
all eluents.

Conclusion: With these 3 chiral phases the majority of  known racemates can be separated.

 
 
 
   
     
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