Lc 20a hplc instrument

The sennoside A, sennoside B and emodin constituents in RRs were determined using RP-HPLC. The HPLC system consisted of a HPLC unit (LC-20A HPLC instrument, Shimadzu Co., Japan) and reversed-phase Shiseido CAPCELL PAK C18 UG120S column (5 μm, 4.6 mm I.D. × 25 cm) was used for sennoside A detection and Biochoff chromatography column (ProntoSIL 250 × 4.6 mm) for sennoside B and emodin detection. For sennoside A detection, the mobile phase consisted of acetonitrile and 1.25 % acetic acid at a flow rate of 0.6 mL/min, with elution of 80 % acetic acid v/v at a flow rate of 1 mL/min at 30 °C. For sennoside B detection, the mobile phase consisted of acetonitrile and 0.05 M phosphoric acid at a flow rate of 1 mL/min, with gradient elution of 80 % phosphoric acid v/v at a flow rate of 1 mL/min at 40 °C. For emodin detection, the mobile phase consisted of methanol and 1 % phosphoric acid at a flow rate of 1 mL/min, with elution of 15 % phosphoric acid v/v at a flow rate of 1 mL/min at 40 °C. The injection volume was 10 μL.

Most of the characterizations and analyses were conducted at the Central Laboratory for Microanalysis and Nanotechnology, Minia University, Egypt. The α-HNPs and Azr@α-HNPs were characterized via several instrumental analysis tools starting with the use of the digital balance of 5 digits [CX 265] (Citizen, India), and Eppendorf Centrifuge [5425] (Life science, Germany). FT-IR analysis was recorded on [Nicolet iS10 FT-IR spectrometer] (Thermo Fisher, USA) in a wavenumber range of 4000–400 cm⁻¹ using an ATR module. The morphology of the α-HNPs and Azr@α-HNPs were investigated using scanning electron microscopy [SEM; JSM IT 200] (JEOL, Japan) and transmission electron microscopy [TEM; JEM-100C XII)] (JEOL, Japan), pH-meter [SevenMulti] (Mettler Toledo, Switzerland). Azr quantitative analysis was determined using the LC-20A HPLC instrument with the PDA (Shimadzu, Japan). The method was performed on the reversed-phase column ODS-3 (250 mm × 4.6 mm × 5 μm) (Thermo Scientific, USA).

The growth curves of the R. toruloides strains were determined by measuring the cell density at 600 nm using a Genesys 20 spectrophotometer (Thermo Fischer Scientific Inc., USA). The dry cell weight (DCW) was determined by the previously described method [5 ]. The concentrations of glucose and ethanol were monitored by a LC-20A HPLC instrument (Shimadzu Inc., Japan) equipped with a RID detector as previously reported [15 (link)].