Home / microfluidic application note / Setup: droplet and digital microfluidics / How to handle monodisperse alginate droplets & beads production with microfluidics
Microfluidics application note

How does microfluidics alginate beads production work?

Alginate particles generation microfluidics
Highly monodispersed alginate beads with size in the 50µm range. Experiment results by Elveflow team.

Introduction to alginate beads production

Hydrogel-based delivery systems are finding more and more applications, from encapsulation, protection, to the release of bioactive agents in many fields such as pharmaceutical, supplements, food industries, for cell/bacteria/microbes culture & implantation, and cell-based genes in biological research.

Advantages of using alginate beads

Hydrogel beads fabricated from biopolymers are particularly suitable for the encapsulation of biological thanks to their biocompability and because they often involve mild preparation conditions that do not alter biological properties.

Amongst those, anionic polysaccharide alginate beads offer particular advantages as they can be easily formed or degraded, and also provide a non-toxic microenvironment (cellular/microbial growth) and are highly affordable.

Generally, alginate microgels are prepared by either the external diffusion or internal release of a crosslinking agent into or among dispersed aqueous alginate droplets.

In addition, the size and shape of the beads are often critically controlled, since for many uses the beads have to be monodisperse in size and spherical in shape.

Many applications can be performed using alginates, such as:

Batch method for alginate beads production

A common method to generate alginate beads is by extruding an alginate mixture into a calcium solution. However, this method has major limitations as the generated beads are very large in size (>500µm), are non-spherical and have a very poor reproducibility.

Alginate beads production using microfluidics

Monodisperse alginate droplets
Highly monodispersed alginate droplets, size in the 50µm range. Experiment results by  the Elveflow team.

This application note will show you how highly monodispersed alginate beads can be easily generated by microfluidics droplet generation, following the consecutive steps:

We will first start by preparing an Alginate/EDTA-Calcium solution. Then microdroplets of this solution will be generated using a microfluidic system. Finally, a calcium compound will be released into the droplet by a pH modifying agent (Acetic acid), and will crosslink with the alginate to generate Ca-Alginate beads. Several experimental conditions have been tested to achieve highly monodispersed droplet with sizes within the 50µm range. Other beads size are achievable with a similar setup.

If you want to know more, feel free to contact our team of experts!

Alginate beads production: list of components

Tip: everything you need is included in our alginate bead generation pack

06 MFS Standard flow rate sensor ELVEFLOW MICROFLUIDICS
03 MFP Inline pressure sensor ELVEFLOW MICROFLUIDICS
Microfluidic Reservoir for 15 mL Falcon Tube – S with tubing

Alginate beads production: materials

Hardware:

Chemicals:

  • Alginate (low viscosity)
  • Calcium-EDTA
  • Acetic acid
  • HFE7500 oil with 2% surfactant
  • Droplet breaking solution

Alginate beads production: Step by step method

Step 1: Solutions preparation

Alginate beads generation, solution preparation

Tank 1: Alginate & Calcium EDTA

Mix 2% w/w alginate/water solution and add 0.5M Calcium-EDTA into the mix.

Vial 1: Acetic acid solution

Prepare Acetic acid solution. Depending on needed gelation time use up to 2% acetic acid for immediate gelation and below 0.2% for slow gelation (not recommended to use below 0.05%).

Step 2: Generation of Alginate/EDTA-Calcium droplets

Microfluidic setup used to generate highly monodispersed droplet with size in the 50 µm range.

Microfluidic setup to generate alginate droplets with a microfluidic chip

Step 3: Adding acetic acid for Ca2+ ions release leadind to Ca-alginate crosslinking and beads formation

Acetic acid ixing with alginate droplets

Add the acetic acid solution, and mix to let the acid better access the droplets.

Acetic acid will react with the calcium carbonate to release calcium ions. Through crosslinking reaction with the alginate, the calcium ions will produce Ca-alginate microspheres

alginate beads generation sketch

 

Step 4: Adding emulsion breaker to release beads from droplets

Once the gelation finished, droplets should be broken using droplet/emulsion breaking solution.

Droplet breaking solution will remove the surfactant from the droplets to release the alginate beads.

Microfluidic alginate beads

User guide alginate beads production book

User guide alginate beads production

    Add your email adress to receive the user guide

    Want to run a similar experiment? Feel free to contact us at: contact@elveflow.com
    Elveflow team at work

      How can we help you?




      We will answer within 24 hours

      By filling in your info you accept that we use your data.

      Contact
      How can we help you?
      Quoteor technical request Job application Job
      application
      Collaboration or partnerships Collaborations
      or partnerships
      Customer support Customer
      support
      Others questions Other

        Get a quote




        We will answer within 24 hours

        By filling in your info you accept that we use your data.

        Contacting for
        a job application?
        We are happy that you are interested in Elveflow. You can apply to our open jobs or send us your open application on WelcomeToTheJungle. Over here!

          Collaborations




          We will answer within 24 hours

          By filling in your info you accept that we use your data.

            Need customer support?







            I hereby agree that Elveflow uses my personal data

            We will answer within 24 hours

              How can we help you?




              We will answer within 24 hours

              By filling in your info you accept that we use your data.