In this research, we conducted a systematic evaluation of the synthesis parameters of a multi-responsive core-shell nanocomposite (Fe3O4 nanoparticles coated by poly(N-isopropylacrylamide) (PNIPAM) in the presence of chitosan (CS) (Fe3O4@PNIPAM-CS). Scanning electron microscopy (SEM) was used to follow the size and morphology of the nanocomposite. The functionalization and the coating of Fe3O4 nanoparticles (Nps) were evaluated by the ζ-potential evolution and Fourier Transform infrared spectroscopy (FTIR). The nanocomposite exhibited a collapsed structure when the temperature was driven above the lower critical solution temperature (LCST), determined by dynamic light scattering (DLS). The LCST was successfully shifted from 33 to 39 °C, which opens the possibility of using it in physiological systems. A magnetometry test was performed to confirm the superparamagnetic behavior at room temperature. The obtained systems allow the possibility to control specific properties, such as particle size and morphology. Finally, we performed vincristine sulfate loading and release tests. Mathematical analysis reveals a two-stage structural-relaxation release model beyond the LCST. In contrast, a temperature of 25 °C promotes the diffusional release model. As a result, a more in-depth comprehension of the release kinetics was achieved. The synthesis and study of a magnetic core-shell nanoplatform offer a smart material as an alternative targeted release therapy due to its thermomagnetic properties.

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In the present paper we report a novel synthesis method of silicon quantum dots (SiQDs) using 3-Aminopropyltriethoxysilane (APTES) as silicon precursor and low molecular weight chitosan (CS) as reducing agent. The obtained SiQDs have a hydrodynamic diameter of 2.3 nm, water dispersible, presents blue emission band at 434.5 nm (2.85 eV) with a Commission Internationale de l’Eclairage 1931 (CIE1931) chromaticity coordinates (x = 0.1665, y = 0.1222), the experimental absorbance of the SiQDS was measured and the band gap (Eg) was estimated through PerkinElmer’s method, the obtained value was 3.1 eV and a positive ζ-potential of + 35 mV, resulting in photonics, microelectronics, and biotechnological potential applications.