The table below shows the cleaning and regeneration steps required for each of the qEV columns.
For the best cleaning of your qEV columns, we now recommend:
- qEVoriginal: 10 mL 0.5 M NaOH followed by 20 mL buffer.
- qEV2: 100 mL buffer, followed by 2 mL 0.5 M NaOH, followed by 100 mL buffer.
- qEV10: 140 mL buffer, followed by 5 mL 0.5 M NaOH, followed by 140 mL buffer.
20% Ethanol can also be used to store columns, however if a concentrated electrolyte such as 2x PBS is used, flush the column with DI water before introducing 20% ethanol otherwise salt will precipitate out inside the column and render the column unusable.
Single use is advisable where the vesicle fractions are to be analysed using PCR or RT-PCR.
Degassed buffers will help avoid air bubbles forming in the gel bed. A small number of air bubbles will have minimal effect on the column performance.
It is recommended to use a buffer with an ionic strength of 0.15 M or greater to avoid any unwanted ionic interactions between the solute molecule and the matrix.
To avoid clogging of column filters, it is recommended to filter or low-speed centrifuge the biological sample to remove large particulate matter.
If the flow rate doesn't improve after NaOH cleaning procedure, wash with surfactant (e.g. Triton X-100). If the flow rate still doesn't improve, the column is probably irreversibly blocked and should be discarded.