Dear all, chains architecture influences to a great deal the spatiale arrengement and close packing. Presence of net charges, stiffness of the main backbone, and bulky side groups, all contribute to affect particle size and shape. In addition to structural parameters, preparation techniques of nanoparticles also influence the size and shape. It is generally agreed that anti-solvent previpitation technique is the most simple and efficient technique to produce nanoparticles with average size ~200nm with good size distribution. My Regards

Hi Antonio,

The short answer to your question is, the size of the polymer depends on both its polymer properties as well as the extraction process.

To be specific on your polymer of interest, the size of alginate (as it is usually extracted in the anionic form) molecules is heavily dependent on the extraction method and you can find several extraction methods in literature. You mention that you'll be using the same extraction method for the different seaweed samples. I would expect that you'll see significant differences in the size of alginate molecules from one source to another if the seaweed samples are different enough. Alginate is a linear polymer and therefore branching is not a factor that determines these changes in the molecular weight. From my reading and research experience with alginate, two monomers (d-mannuronic and l-guluronic acids) that make alginate molecules are bound differently creating homopolymeric M-M, and G-G regions in the polymer network. I believe that this organization plays a major role in determining the molecular weight of the polymer. I have seen the d-mannuronate content in alginate changing in range from 35-65 % for alginates extracted from different sources. The hydroxyl (or the carboxyl) content does not change regardless of the monomer ratio as both the monomers have the same number of functional groups (two -OH and one carboxyl group per monomer). Even though the functional groups are the same, when it comes to solubility, you'll see significant differences due to their molecular weight and monomer ratio.

I hope this answered some of the questions you had related to alginate.

Dear all, chains architecture influences to a great deal the spatiale arrengement and close packing. Presence of net charges, stiffness of the main backbone, and bulky side groups, all contribute to affect particle size and shape. In addition to structural parameters, preparation techniques of nanoparticles also influence the size and shape. It is generally agreed that anti-solvent previpitation technique is the most simple and efficient technique to produce nanoparticles with average size ~200nm with good size distribution. My Regards

Hi;

The chemical structure of the polymer, the molecular weight, the polymolecularity index, the rigidity and the configuration of the chains, the lateral groups present along the chains as well as the mode of synthesis are all parameters influencing the shape and size of the polymer particles.

With my best regards

Both matter. In some way, one can imagine that for smaller particles the properties matter more, whereas for larger particles the process may be the main influence on size. But it all depends. In the extreme situation of micelles, the size is very directly related to for example chain length of the 'monomer' forming the micelle.

Dear Antonio Alves

I think yes the physiochemical properties of the polymer play a role in the size of particles. Form my experience, I used tow type of alginate from different sources they give me different beads hardness or size because different in M and G contents as well as the length of each block. These properties change the viscosity of the alginate solution or the surface tension that lead to change in the particles properties.

previous studies:

Chapter Physicochemical Characterisation of Alginate from Malaysian ...

Article Alginate lyase: Review of major sources and classification, ...