Au 2701 uv vis double beam spectrophotometer

A stock of 1 mg/mL of the A. nilotica (L.) leaf extract was prepared using 0.1% ethanol. From this, 100 μL was taken and diluted to 3 mL with methanol. Wave scan analysis was carried out using Systronics AU-2701 UV-Vis double beam spectrophotometer in the wave length ranging from 200 to 800 nm. The peak obtained was compared with that of ethyl gallate. Following this, A. nilotica (L.) leaf extract was dissolved in HPLC grade methanol at a concentration of 1.0 mg/mL, filtered through 0.22 μm filter and subjected to HPLC Schimadzu isocratic system equipped with Luna C18 column. Separation was achieved using acetonitrile/water and the peak obtained was compared with the pure ethyl gallate as standard at 272 nm.
Validation of the presence of ethyl gallate in A. nilotica (L.) leaf extract with different solvents were also done using YOUNGLIN HPLC instrument Acme 9000 with vacuum degasser and mixer. The instrument was equipped with a gradient pump SP930D, a UV/Vis detector UV730D and a Kromasil 100-5C18 column with a length of 250 x 4.6 mm. Data was integrated by the software YOUNGLIN Autochro-3000 chromatograph data system. Separation was achieved by isocratic mobile phase consisting of methanol-acetonitrile-10 mM ammonium acetate containing 0.1% formic acid (10:25:65, v/v/v) with a flow rate of 0.5 mL/min. Peak area of the sample was compared with that of the standard at 291 nm.

FTIR spectroscopy is widely used in recent years for the interaction studies of DNA with natural compounds. A solution of CT-DNA was made with 10 mM Tris-HCl buffer of pH 7.4 and its purity was verified by its absorbance at 260 and 280 nm. Different concentrations of DNA (0.1 to 1 mg mL^-1) were analyzed for its binding capacity with a single concentration of A. nilotica (L.) leaf extract or ethyl gallate [18 (link)].
IRAffinity-1 FTIR spectrophotometer (Shimadzu, Columbia, Maryland, USA) was used for recording the spectra using DTGS detector, Ni-Chrome source and KBr beam splitter. One hundred scans for each sample with 4 cm^-1 resolution were recorded and evaluated using OMNIC software. The interaction of A. nilotica (L.) leaf extract and ethyl gallate with CT-DNA was evaluated by comparing the shift in the spectrum formed individually or as complexes. A UV-Visible spectrum was also recorded by wave scan range from 200 to 800 nm using Systronics AU-2701 UV-Vis double beam spectrophotometer (Gujarat, India).