Simultaneous determination of theobromine (THEOB), theophylline (THEOP) and caffeine (CAF) in commercially available food products using UPLC technique

The aim of the current investigation to estimate the amount of theobromine (THEOB), theophylline (THEOP) and caffeine (CAF) concurrently using ultra performance liquid chromatography with photo diode array detector (UPLC-PDA) in ultrasound assisted extract of commercially available food products. The commercially available products are categorized in three different groups including teas, coffees and chocolates. The UPLC approach is rapid, precise, highly sensitive and cost effective for the concurrent assessment of THEOB, THEOP and CAF in ultrasound assisted extract of commercially available food products. The mobile phase comprises a mixture of water and ACN (90:10, v/v) for the concurrent assessment of THEOB, THEOP and CAF in ultrasound assisted extract of commercially available food products. The current approach operated on a linear scale range of 6.66-33.3 ng mL^-1, 3.33-33.3 ng mL^-1 and 3.33 - 33.3 ng mL^-1, respectively, for THEOB, THEOP and CAF at 272.5 nm wavelength. The LOD for THEOB, THEOP and CAF were assessed to be 1.10 ± 0.001, 0.75 ± 0.000 and 0.48 ± 0.002 ng mL^-1, respectively by applying the present approach. The LOQ for THEOB, THEOP and CAF were assessed to be 3.35 ± 0.009, 2.29 ± 0.001 and 1.47 ± 0.001 ng mL^-1, respectively by applying the present approach. These findings confirmed that the current UPLC approach is highly sensitive, accurate, precise and robust for the concurrent assessment of THEOB, THEOP and CAF in ultrasound assisted extract of commercially available food products. Antioxidant activity of different teas, coffees, chocolates as well as standard THEOB, THEO and CAF were determined by DPPH method.