Question

12. In a HPLC chromatogram, peak A elutes at 2.5 min and peak B elutes at 3.0 min. The width of peak A is 0.8 min and peak B is 0.6 min. What is the resolution? Are these two peaks baseline resolved (explain your reasoning)? If not, change a specific parameter that would make these two peaks baseline resolved and calculate new resolution. Diagram both chromatograms (original question and baseline resolved) (8 pts)

Answer 1

Here resolution between two peaks is calculated by the formula :-

Resolution (R_s) = (t_b - ta) /{ (w_a + w_b) /2

}
So, if we do half the width of each peak then this can make two peaks A and B baseline resolved. New width of peak A (WA) 0.4min New width of peok B (Lop') = 0.3min. Retention time for Peak A(EA)= d.5 min Retention time for peak B (to) = 3.0min New Resolution (Rs) = ? &s=w to-ta ( WA'+WB' Rs' = 3.0-2.5 0.5x2 = 1.0 (0.4+0.31 0.7 Rs' = 1.44 RS" = 1.44 close to 1.5. peaks are nearly resolved. t omin So two TA rigii) New Resolution Detector signal mg Chromatogram. infection 2 A polnt e twa = 0.4min wote 0.3 mm Time (mins)

So, if we do half the width of each peak then this can make two peaks A and B baseline resolved. New width of peak A (WA) 0.4min New width of peok B (Lop') = 0.3min. Retention time for Peak A(EA)= d.5 min Retention time for peak B (to) = 3.0min New Resolution (Rs) = ? &s=w to-ta ( WA'+WB' Rs' = 3.0-2.5 0.5x2 = 1.0 (0.4+0.31 0.7 Rs' = 1.44 RS" = 1.44 close to 1.5. peaks are nearly resolved. t omin So two TA rigii) New Resolution Detector signal mg Chromatogram. infection 2 A polnt e twa = 0.4min wote 0.3 mm Time (mins)