|It is general to set up conditions using a column of analysis size and, then, shift to fractionation size because examination of optimal separating conditions
directly with a fractionation column requires a large volume of sample and fractionation columns are expensive.
In this case, it must be noted that the conditions cannot be shifted smoothly if the particle size distribution of fillers differs between the analysis column and fractionation
column. Although such problem does not occur if the same filler is used in the analysis and fractionation, use of the filler for the analysis size in the fractionation results
in a high pressure restricting conditions.
On the contrary, even if the pressure is low, the advantages of HPLC fractionation are not utilized if the number of theoretical plates is small. That is to say that key to
smooth transfer of conditions to a large size column is the use of a filler specific for fractionation that exhibits a certain level of separation performance and low pressure
during use. Then, concerning the issues associated with transfer of conditions, parallel relationship is established for the amount of injection and the number of theoretical
plates or separation capacity between columns of different diameters allowing smooth transfer of conditions provided that the linear velocity of the mobile phase is the same.
This means that examination of optimal separating conditions using a column of analysis size allows transfer of conditions to a column of fractionation size.
Fractionation of arbutin is illustrated as an example of application of fractionation using a filler meeting the above conditions. It can be seen that the pressure is
controlled low, and the filler exhibits almost the same performance from a column 4.6 to 50 mm in inside diameter.
Wakosil-II 5C18 RS Prep is a low-cost and high-performance fractionation filler 5 μm in particle size prepared for fractionation while retaining the advantages of RS filler
for analysis. We offer wide ranges of fillers for fractionation, HG Prep, AR Prep and 5 SIL Prep, allowing smooth transfer to fractionation. Please ask for information.