We have developed a novel spray gelation-based method to synthesize a new series of magnetically responsive hydrogel nanoparticles for biomedical and drug delivery applications. The method is based on the production of hydrogel nanoparticles from sprayed polymeric microdroplets obtained by an air-jet nebulization process that is immediately followed by gelation in a crosslinking fluid. Oligoguluronate (G-blocks) was prepared through the partial acid hydrolysis of sodium alginate. PEG-grafted chitosan was also synthesized and characterized (FTIR, EA, and DSC). Then, magnetically responsive hydrogel nanoparticles based on alginate and alginate/G-blocks were synthesized via aerosolization followed by either ionotropic gelation or both ionotropic and polyelectrolyte complexation using CaCl₂ or PEG-g-chitosan/CaCl₂ as crosslinking agents, respectively. Particle size and dynamic swelling were determined using dynamic light scattering (DLS) and microscopy. Surface morphology of the nanoparticles was examined using SEM. The distribution of magnetic cores within the hydrogels nanoparticles was also examined using TEM. In addition, the iron and calcium contents of the particles were estimated using EDS. Spherical magnetic hydrogel nanoparticles with average particle size of 811 ± 162 to 941 ± 2 nm were obtained. This study showed that the developed method is promising for the manufacture of hydrogel nanoparticles, and it represents a relatively simple and potential low-cost system.

中文翻译：

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通过用于生物医学和药物输送应用的新型气溶胶辅助方法制备的智能磁响应水凝胶纳米颗粒。

我们开发了一种新的基于喷雾凝胶化的方法来合成一系列新的磁响应水凝胶纳米粒子，用于生物医学和药物递送应用。该方法基于从喷气式雾化过程获得的喷雾聚合物微滴生产水凝胶纳米粒子，然后立即在交联流体中凝胶化。Oligoguroronate (G-blocks) 是通过海藻酸钠的部分酸水解制备的。还合成并表征了 PEG 接枝的壳聚糖（FTIR、EA 和 DSC）。然后，基于海藻酸盐和海藻酸盐/G-blocks 的磁响应水凝胶纳米粒子通过气雾化合成，然后使用 CaCl ₂或 PEG-g-壳聚糖/CaCl进行离子型凝胶化或离子型和聚电解质复合₂分别作为交联剂。使用动态光散射 (DLS) 和显微镜确定粒度和动态溶胀。使用SEM检查纳米颗粒的表面形态。还使用 TEM 检查了水凝胶纳米粒子内磁芯的分布。此外，颗粒的铁和钙含量是使用 EDS 估计的。获得了平均粒径为 811 ± 162 至 941 ± 2 nm 的球形磁性水凝胶纳米粒子。该研究表明，所开发的方法有望用于制造水凝胶纳米粒子，并且它代表了一种相对简单且潜在的低成本系统。