Hi Ashwani,

You can prepare two different solutions of sodium alginate and calcium chloride separately in DI water. To prepare the microparticles take the sodium alginate solution in the capillary(it will be normal aqueous soln.) and pour it slowly into the calcium chloride solution. It will get crosslinked immediately and forms the microparticles.

Thank you

Thank you, Ms. Nandini and Mr. Michael for your valuable suggestions. I shall follow your procedure and come back to you.

Thanks again

What Ms. Nandini told was, how to prepare sodium alginate gel using calcium chloride, but your suggestion will address my problem.

Thank you, Mr. Michael

In general, chelating agents can be used to dissolve ionically crosslinked polymers such as alginate by scavenging the divalent calcium ions.

you will need to sequester the Ca2+ to delay the set.  There a several ways this can be accomplished.  You should read: "Release of bovine serum albumin from a hydrogel-cored biodegradable polymer fiber"

Authors

B. B. Crow,

Hi Ashwani, 

Give try to use 10 - 100 mM citrate with pH>5 (pH below 5 can result in formation alginic acid gel). I have got a good experience with 50 mM sodium citrate solution with pH 7.4. In any case dissolving anything what has plugged a microfluidic channel may take good deal of time.

Jan

read Jay Palmer good answer

You may possibly want to check also the following somewhat related discussions: https://www.researchgate.net/post/Does_change_in_pH_of_sodium_alginate_affect_final_encapsulated_cell_viability https://www.researchgate.net/post/How_can_I_make_alginate_disks_that_I_can_put_into_a_24-well_plate/1

About predicting the pH of CaCl2 aq. solutions ― cf. my posts at: https://www.researchgate.net/post/How-to-increase-pH-for-a-solution-without-making-a-chemical-reaction-with-CaCl2

You can use EDTA

Jan Víteček

Is this method effective in blocking PDMS channels with gel and does it not cause a problem for PDMC walls?