Page 16 - CS03_Hudz

 The principle of aluminum chloride colorimetric

method is that aluminum chloride forms complexes

with flavons and flavonols wherein it reacts with the

C-4 ketogroup and either the C-3 hydroxyl group of

the ring C, and/or C-5, C-7 hydroxyl group.

 Such flavonols as galangin, morin, kaemferol, rutin,

quercetin, quercitrin and myrecetin have absorption

maximum at 415-440 nm while the absorption

maximum of complexes formed by chrysin and

apigenin were at 395 nm and 385 nm, respectively.

Another flavon had the maximum absorption of

complex with Al at 415 nm.

 Our study confirms these data: сomplex of quercetin

with aluminum chloride had the maximum absorption

at 423.8-427.2 nm in differential spectra in the range

of quercetin concentrations of 2.08-32.2 mg/L

(figures 5 and 6).