Chromatography Focus
Figure 1. Components of Quattro CCC
difference between L-LC and S-LC is that in L-LC, the instrument design maintains one of the pair of immiscible liquids stationary, and in S- LC immobilisation is by adsorption of a liquid onto a solid particle. Both S- LC and L-LC can be used in isocratic and step/linear etc gradient modes [1, 2, 3, 4]. As S-LC and L-LC are potentially similar in chromatography chemistries etc, should they be equally popular and equally understood?
The earlier statement in this Introduction defines the answer; too many fundamentally different designs of L-LC are not mutually compatible. Varying key design parameters in a single concept can lead to excessive scale-up failures.
What then is the solution for successful L-LC design? The one chosen uniquely for the Quattro L-LC™ for hydrodynamic L-LC was to fix as many key L-LC design parameters as possible. The totally modular design, uniquely keeps as many key L-LC design parameters the same as practical, from smallest L-LC MS, 7ml coils to 100+ litre process L-LC capable of multiple tonnes per annum production.
CONTEXT OF MODULAR QUATTRO OPEN TUBULAR, HIGH PERFORMANCE LIQUID-LIQUID CHROMATOGRAPHS™ (OT HPL-LC™).
Figures 1 & 2 show the chassis and coil/volume options of the Quattro L-LC™ model range (‘J’ Type, Planetary Centrifuge, open, constant id tubing, wound on a planetary bobbin, with no rotating seals). The bobbins (paired planetary rotating bodies, holds the coiled, tubing columns) can have tubing with different material choice. Options include PTFE, Stainless Steel or Titanium. Tubing bore id can vary from 0.5 to 12.5mm, and volumes from 7 to 3000ml for a single rotor assembly. A single bobbin can have two coils. All models except the entry IntroPrep™ have two dynamically balanced bobbins, with up to 4 coils as an option. Each coil can be used
Figure 2. Scale-up Parameters
independently for same or different preparations, or used in any combination, in series with any coil or multiple of coils of the same id. Uniquely for hydrodynamic L-LC model ranges, all models share the same key L-LC design parameters, inclusive of the same sun and planet radii, speed ranges, beta values, winding techniques and only tubing bore is varied.
This model range is also the only one that allows even the largest bore to be tested on a laboratory based unit, prior to introduction to process based preparation. Hybrid coil winding, that is multiple ids in the same instrument or bobbin, can be custom produced. Multiple bobbin sets for a single chassis are available. In this way the major difficulty with competitor’s ranges of needing several different instruments, to validate scale-up, is avoided.
For Process Chromatography, the base module is of 3 litres. Bobbins are interchangeable, and can be exchanged for re-winding if PTFE tubing chosen and cGMP requires virgin material.
Most would use stainless steel or titanium tubing and appropriate cleaning techniques, but renewing PTFE coils is an option. If different bore sizes are required, different paired sets of bobbins may be used. Any number of rotors can be used in series, in parallel or in SMB operations. Clutches and switching valves allow operating mode changes.
RESULTS & DISCUSSION
A discussion of AECS-QuikPrep Ltd Case Studies, completed with a Quattro L-LC™ which demonstrate the considerable benefits, and inter- compatibilities of Open Tubular, High Performance Liquid-Liquid Chromatography™/OT HPL-LC™ and Preparative HPLC in problem solving for a variety of Industries/different applications.
Figure 3. Purification of a new BioActive using L-LC
Realism in L-LC for laboratory or process scale-up:
Much of the information that is known on problems of L-LC scale-up and design incompatibility is only discussed verbally within the L-LC community. These negatives are rarely published. We will confirm unpublished Grant funded research (‘The Industrial Scale up of Countercurrent Chromatography’. BBSRC/DTI LINK Award Ref: 100/BCE08803. Feb 98 - Jan 00 (£322,668), a collaboration of AECS, Brunel University, University College of Swansea, GSK, Zeneca & Shell Research supported comments by CCC/CPC experts (information acquired verbally) that CCC/CPC of different designs or even a single concept, if we vary the key parameter will on occasions prohibit scale-up. Keeping all parameters the same, only changing tubing bore, certain scale- ups failed. We interpreted the implications of these results so seriously that we embarked on total product redesign of a 7-year prior commercial Quattro CCC™ product. The Quattro L-LC™ post 2000 changed to a unique, modular concept for its whole product range, in order to minimise variability. Since then an additional 9 years has been spent increasing understanding, in order to minimise scale-up failures.
Quattro L-LC™ purifies and concentrates in one step:
During the above LINK Grant project working with GSK the results shown in Figure 3 were obtained. Two HPLC gradient traces are shown. Top is original HPLC. Below is the HPLC of a single 4ml fraction from a 200+ ml gradient Quattro L-LC™ run. Insert shows the amount of target in fractions before and after the main fraction. Over 90% of target was in one single 4ml fraction. The bars labelled F above top chromatograph show polarity range of L-LC fractions. Apart from solvent front, all show the very small polarity range of OT HPL-LC fractions. An unknown bioactive was found.
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128 |
Page 129 |
Page 130 |
Page 131 |
Page 132 |
Page 133 |
Page 134 |
Page 135 |
Page 136 |
Page 137 |
Page 138 |
Page 139 |
Page 140 |
Page 141 |
Page 142 |
Page 143 |
Page 144 |
Page 145 |
Page 146 |
Page 147 |
Page 148 |
Page 149 |
Page 150 |
Page 151 |
Page 152 |
Page 153 |
Page 154 |
Page 155 |
Page 156 |
Page 157 |
Page 158 |
Page 159 |
Page 160 |
Page 161 |
Page 162 |
Page 163 |
Page 164 |
Page 165 |
Page 166 |
Page 167 |
Page 168 |
Page 169 |
Page 170 |
Page 171 |
Page 172 |
Page 173 |
Page 174 |
Page 175 |
Page 176 |
Page 177 |
Page 178 |
Page 179 |
Page 180 |
Page 181 |
Page 182 |
Page 183 |
Page 184 |
Page 185 |
Page 186 |
Page 187 |
Page 188 |
Page 189 |
Page 190 |
Page 191 |
Page 192 |
Page 193 |
Page 194 |
Page 195 |
Page 196 |
Page 197 |
Page 198 |
Page 199 |
Page 200 |
Page 201 |
Page 202 |
Page 203 |
Page 204 |
Page 205 |
Page 206 |
Page 207 |
Page 208 |
Page 209 |
Page 210 |
Page 211 |
Page 212 |
Page 213 |
Page 214 |
Page 215 |
Page 216 |
Page 217 |
Page 218 |
Page 219 |
Page 220
