Alginate nanohydrogels prepared by emulsification-diffusion method

Abstract

This study reports the preparation and characterization of nanohydrogels by using sodium alginate as a model material. Alginate nanohydrogels (ANH) were prepared by emulsification-diffusion method in a w/o system with 1,2-diacyl-sn-glycero-3-phosphocholin as the lipophilic surfactant. The effects of the alginate to surfactant ratio and the remaining water contents on the mean particle size and swellability of ANHs were investigated in terms of the concentration, agitation speed, and agitation time. The feasibility of using nanohydrogels and their controllability were proved by the water the absorbency of ANHs during a 7-day evaluation by dynamic light scattering. In this work, the mean particle sizes of ANHs could be controlled from 49.2 nm (measured in ethanol phase) to 1.9 μm (measured in water phase, after 7 days of water absorption).

Controlled release of BMP-2 from alginate nanohydrogels enhanced osteogenic differentiation of human bone marrow stromal cells

“…In the case of the ANH, to ensure the sufficient diffusion of water and the solidification of nanoparticles, the emulsion was left at room temperature for 3 days. 28 On the other hand, in the case of the BMP-2@ANH, proteins may be readily diffused out of the nanohydrogels for 3 days. To minimize the loss of BMP-2, the emulsion was left only for 10 min, which led to insufficient diffusion of water, aggregation, and accordingly, larger particles size.…”

“…The preparation of BMP-2@ANH were based on the modified emulsificationdiffusion method described in the previous paper. 28 Briefly, 0.1 g of sodium alginate (Junsei Chemical, Japan) and 4×10 -6 g of BMP-2 (Peprotech, USA) were dissolved in 20 mL of water. This aqueous solution was saturated with equivalent amount of chloroform (Duksan Pure Chemical, Korea) with 1,2-diacyl-sn-glycero-3-phosphocholin (Cholin II) (Sigma, USA) to reach the state of thermodynamic equilibrium.…”

Near-infrared polyfluorene encapsulated in poly(ε-caprolactone) nanoparticles with remarkable large Stokes shift

“…Chloroform (water solubility 0.809 g/100 mL at 20 C, dielectric constant 4.8) was used instead to dissolve the NIR dye and PCL yielded a blue transparent mixture. 26 Firstly, the partially watersoluble chloroform was saturated with DI water ensuring an initial thermodynamic equilibrium of both liquids which can avoid mass-transfer during the process. 27 The reaction began aer the addition of surfactant dissolved in chloroformsaturated water into water-saturated chloroform containing a mixture of PCL and NIR dye under ultrasonic treatment.…”

Fabrication and Characterization of Starch Nanohydrogels via Reverse Emulsification and Internal Gelation

“…These results are in alignment with those of Lee et al, who reported that the sizes of alginate nanohydrogels obtained by TEM observation were much smaller. 40 XRD. The XRD patterns of nanohydrogels prepared with different retrogradation times are shown in Figure 5.…”