Figure 49 : Any calibration line has an uncertainty at best shown graphically. Normally never the calibration line can be extrapolated. Your data MUST stay within the calibrated values. NOT: it is useless to make statements about the ZERO point, as at x = 0 there is no sampling possible. You cannot sample NOTHING, separate nothing, and hope you see a real signal zero. You simply detect nothing. The expected zero signal is virtual. Normally never TLC / HPTLC calibration lines meet zero data. In addition at zero gram substance nobody can really measure...
