A flow of approx. 1 mL/min is a good choice. Try to maintain always the cartridge with liquid (do not dry) because this can reduce recovery (unless you use specially designed cartridges as Oasis from Waters)

Hi Rahul,

It really depends on the solid phase extraction material that you are using.  What is it?

Best

Hediye

Hi Madam,

Its polar components......

What is that you are extracting and with what sorbent. Is it in a glass or stainless tube. What solvent do you intend to use. 

Hi sir,

WQe using commercial Waters Sep-Pack SPE c18 cartridge 500 mg , we are eluting sample in methanol and dissolving and loading in water.

Hi Rahul,

1) Condition the cartridge: wash it with distilled deionized water (DDW)first follow by any other conditioning recommendation by the manufacturer.

2) Leave it in  DDW for full hydration at least 3 hours, no more than 24 h is needed.

3) Adjust your flow rate with DDW (1 ml/min is fine to start)

4) add your sample at this flow rate

5) wash again with DDW (assuming analyte(s) of interest were retained (2 times the volume capacity of the cartridge 

6) elute with Methanol and collect your sample (monitor elution to determine minimum volume required)

I hope this help,

Wilber

Hi Rahul,

Regardless of what you want to do, I suggest you make a factorial design to optimize the conditions. You can use as engineering factors: the solid phase, the solvents, the volume eluents and elution time.

New conditions/experimental may require a good optimization and validation.

Dear Sir. Regarding your issue about the Solid Phase Extraction understanding. Solid phase extraction (SPE) is an increasingly useful sample preparation technique. With SPE, many of the problems associated with liquid/liquid extraction can be prevented, such as incomplete phase separations, less-than-quantitative recoveries, use of expensive, breakable specialty glassware, and disposal of large quantities of organic solvents. SPE is more efficient than liquid/liquid extraction, yields quantitative extractions that are easy to perform, is rapid, and can be automated. Solvent use and lab time are reduced. SPE is used most often to prepare liquid samples and extract semivolatile or nonvolatile analytes, but also can be used with solids that are pre-extracted into solvents. SPE products are excellent for sample extraction, concentration, and cleanup. They are available in a wide variety of chemistries, adsorbents, and sizes. Selecting the most suitable product for each application and sample is important. For more details the following below links may help you in your analysis:

http://www.sigmaaldrich.com/Graphics/Supelco/objects/4600/4538.pdf

Thanks

Thanks a lot  Isam Eldin Hussein Elgailani sir, Wilber menendez sanchez sir for gr8 support.........thanks to all for your valuable guidance.