CBC 432

First point: Shown in the earlier slide regarding the condition for the GC analysis Only condition mentioned in the paper, no variation of conditions for the GC analysis Variation of conditions for GC analysis is important due to that paper mentioned that tweaking conditions such as gas flow rate, temperature of injector, column temperature, type of carrier actually helps in a better resolution of the peaks.

2nd point Stated a LOD value of 5 to 15 ng/ml Known that LOQ value is actually more reliable than LOD Can improve similar in another paper, stated both LOD and LOQ value

3rd point PCB itself is non-polar and their lipophilicity increases with the degree of chlorination Hexane which is non-polar solvent was used as the extraction solvent in the paper reviewed However, there are other non-polar solvent present No comparison of the different non-polar solvent that can be used for extraction nor is it any mention of reason for using hexane On the other hand on another paper, there is a comparison between 3 different solvent used as well as the efficiency of them In that paper, toluene is the best extraction efficiency

Last point Only did spiking levels of 50 and 100 ng/ml No reason given why Feel that probably just chose a spiking level to start with, and probably others can improve on their work