Lc2695

The analysis of P. harmala alkaloids was performed, according to our previously reported method,^{16 (link)} by RP-HPLC using a Waters LC 2695 coupled to
a Waters 996 diode array detector (DAD). A 100 × 4.6 mm² id, 5 μm, XTerra MS-C18 column (Agilent Technologies) was
used for analysis. Chromatographic conditions were water supplemented
with triethylamine (pH 8.6) (A) and acetonitrile (B). The gradient
was programmed from 0% B (100% A) to 20% B in 4 min, then 30% B at
9 min, 50% B at 14 min, and finally to 60% B at 16 min. The separation
was followed by a 2 min washing procedure with 100% B and a reequilibration
period of 4 min. Flow rate: 1 mL/min, column temperature: 25 °C,
injection volume: 20 μL, and absorbance detection: 320 nm. Under
these conditions, the elution order was peganine, harmol, and harmaline.
These peaks were compared to standard harmine, and the isolated alkaloids
were peganine, harmol, and harmine when injected individually on HPLC
(Figure 1). The isolated
ones were annotated by their mass and UV spectra (Figures S1 and S2). Calibration curves were constructed for
peganine, harmol, and harmine to be used in the measurement of encapsulation
efficiency and in vitro release studies.