Table 4: Regression parameters of analysed vitamins. Regression parameters (regression equation [±SD of slope and intercept] and regression coefficient) and detection limits (signal-to-noise ratio = 5 and injection volume = 3 μL).

VitaminLimit of detection [ ng μL−1 ] at given UV (λ, [ nm ] )Regression lineRegression coefficient

C0.5 ng μL−1 (230 nm) 𝑦 = 0 . 6 5 7 ( ± 0 . 0 0 3 ) 𝑥 + 1 2 7 . 1 ( ± 0 . 0 0 2 ) 𝑅 2 = 0 . 9 9 4
B11 ng μL−1 (270 nm) 𝑦 = 8 . 7 8 9 ( ± 0 . 0 0 2 ) 𝑥 + 1 6 . 3 1 ( ± 0 . 0 0 4 ) 𝑅 2 = 0 . 9 9 6
B20.5 ng μL−1 (265 nm) 𝑦 = 3 0 1 . 7 ( ± 0 . 0 0 5 ) 𝑥 + 4 6 7 . 3 ( ± 0 . 0 0 2 ) 𝑅 2 = 0 . 9 9 6
B51 ng μL−1 (266 nm) 𝑦 = 1 . 0 5 2 ( ± 0 . 0 0 8 ) 𝑥 + 6 6 . 4 3 ( ± 0 . 0 0 3 ) 𝑅 2 = 0 . 9 7 9
B6 (PLP)0.5 ng μL−1 (257 nm) 𝑦 = 7 . 4 5 1 ( ± 0 . 0 0 3 ) 𝑥 + 1 2 . 8 1 ( ± 0 . 0 0 4 ) 𝑅 2 = 0 . 9 9 7
B91 ng μL−1 (280 nm) 𝑦 = 2 4 6 . 1 ( ± 0 . 0 0 2 ) 𝑥 + 5 4 . 3 1 ( ± 0 . 0 0 5 ) 𝑅 2 = 0 . 9 9 9
B122 ng μL−1 (230 nm) 𝑦 = 1 3 2 . 9 ( ± 0 . 0 0 7 ) 𝑥 + 2 0 9 . 6 ( ± 0 . 0 0 8 ) 𝑅 2 = 0 . 9 9 5