Figure 6
From: Pre-analytical challenges from adsorptive losses associated with thiamine analysis
Filter retention of 100 nM thiamine in deionized water following passage of (a) 200 mL through 0.2 µm 47 mm polyamide, cellulose nitrate (CN), polyethersulfone (PES), and nylon filters. Water only containing no thiamine was used as a negative control through CN and PES membranes. (b) 200 mL through glass fiber (GF/F and GF/C), and 0.4 μm polycarbonate, 0.45 μm CN, and 0.45 μm cellulose acetate membranes. The results are after vortexing filters in 2 mL alkaline potassium ferricyanide to convert filter-retained thiamine to thiochrome followed by fluorescence detection at λex = 360/40 nm, λem = 450/50 nm. Error bars represent one standard deviation of triplicate thiochrome determinations of the membrane extract.
