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In chromatography, the retardation factor (R) is the fraction of an analyte in the mobile phase of a chromatographic system. [1] In planar chromatography in particular, the retardation factor R F is defined as the ratio of the distance traveled by the center of a spot to the distance traveled by the solvent front. [2]
In high performance liquid chromatography the CRF is calculated from various parameters of the peaks of solutes (like width, retention time, symmetry etc.) are considered into the calculation. In TLC the CRFs are based on the placement of the spots, measured as RF values.
Thin-layer chromatography (TLC) is a chromatography technique that separates components in non-volatile mixtures. [ 1 ] It is performed on a TLC plate made up of a non-reactive solid coated with a thin layer of adsorbent material. [ 2 ]
Retention distance, or R D, is a concept in thin layer chromatography, designed for quantitative measurement of equal-spreading of the spots on the chromatographic plate and one of the Chromatographic response functions. It is calculated from the following formula:
The response factor can be expressed on a molar, volume or mass [1] basis. Where the true amount of sample and standard are equal: = where A is the signal (e.g. peak area) and the subscript i indicates the sample and the subscript st indicates the standard. [2]
The narrow spot-path unique to anticircular HPTLC facilitates automated quantification. When compared to the linear and circular modes, the anticircular mode demonstrates superior separation and significantly heightened sensitivity, especially at higher Rf-values. [2]
The two major products were blue in color confirmed by various chromatographic (TLC and column etc.) separation and spectroscopic (IR, NMR, Mass) identification were named SBB-I & SBB-II (Rf values of 0.49 and 0.19 (chloroform/benzene 1:1, SiO2) in thin Layer Chromatography). [3]
Chromatographic peak resolution is given by = + where t R is the retention time and w b is the peak width at baseline. The bigger the time-difference and/or the smaller the bandwidths, the better the resolution of the compounds.