Analytical methods such as liquid chromatography or mass spectroscopy use chloroacetonitrile as an eluent
NCG samples were dissolved in eluent
solution and passed though a 0.45 um filter before injecting into chromatograph.
The mobile phase was as follows: 0.5% formic acid in Milli-Q[R] Water 95% (eluent
A) and 0.5% phosphoric acid in acetonitrile 90% and 9.5% Milli-Q[R] Water (eluent
In order to choose the most effective eluent
for quantitative stripping of retained ions from the modified disk after extraction of 5 [micro]g [Cu.sup.2+] and [Cd.sup.2+] from 100 mL sample (in the presence of 6 mg ligand in buffer solution pH=8), the ions were stripped with 5 mL of different inorganic solutions such as HCl, C[H.sub.3]COOH, HN[O.sub.3] and HN[O.sub.3] in methanol at different concentrations were used.
- A combination new column with hydroxide eluents
does not require different eluents
(gradient system), but can perform separation with a single eluent
(isocratic system) within 30 minutes.
Filtered and the filtrate washed with saturated sodium chloride solution three times, dry the organic with over anhydrous sodium sulfate overnight, filtered again, evaporated to dryness the filtrate and silica gel column chromatography (silica gel, 200-300 mesh; eluent
, petroleum ether/acetic acid acetate = 20 : 1) to get a white solid powder 0.523 g, yield 78.2%.
Choosing the right column, flow rate, eluent
compositions, and gradient profile can be a difficult process if done from scratch.
Then the fluoroquinolone was eluted with the eluent
, collected into 50 mL distillation flask, and evaporated to dryness at 45[degrees]C under reduced pressure.
A solution of methanol and 0.01 M ammonium acetate buffer (1 : 99 v/v) was used as the eluent
. The elution rate was 0.9 ml/min, and the product was detected spectrophotometrically at 250 nm.
Users can achieve up to six months of autonomous operation by using an online analysis system with integrated eluent
Developing suitable chromatographic conditions can take weeks or even months, especially if extensive column and eluent
optimization are required.