## 4 Conclusions  
The release behavior, morphology, and size distribution of thermosensitive PNIPAM/magnetite nanoparticles can be controlled by the process parameters, such as polymer solution concentration or nanoprecipitation temperature. Process control over nanoparticle features is important when developing nanoparticles for targeted applications. The hybrid nanoparticles are distributed more uniformly when they are prepared at temperatures around and above the LCST (34-38 \({}^{\circ}\)C) due to the volume shrinkage and water molecules expulsion. The doxorubicin release behavior correlates with the nanoparticles' size distribution when polymer concentration is the main control parameter. Furthermore, the thermosensitive approach influences both nanoparticle features and release behavior when  
Figure 8: Fluorescence microscopy images of untreated MCF7 cells and MCF7 cells treated with pristine and DOX-loaded PNIPAM/magnetite NPs for 24 h and stained with phalloidin-FITC (green fluorescence—actin filaments) and DAPI (blue fluorescence—cells nuclei).  
nanoprecipitation temperature is the main control parameter. The biological assessment revealed that doxorubicin-loaded nanoparticles displayed a significant activity over MCF7 cell viability and cytoskeleton organization, while pristine nanoparticles displayed good biocompatibility with these cells. The nanoparticle size and release behavior play a vital role in anti-cancer activity. The reduced size increases the cancer cells' uptake potential, while the release behavior contributes to doxorubicin accumulation inside cancer cells. In conclusion, the characteristics of the nanoparticles can be optimized through the nanoprecipitation parameters to develop these nanocarriers for cancer management. The results revealed that the PNIPAM/magnetic drug-loaded systems can be used for a future study that includes radiation therapy potential. The uptake potential within MCF7 cancer cells is relevant for a complex biological assessment where a dual approach can be presented: anti-cancer chemotherapy and magnetic hyperthermia as synergistic effect.  
Conceptualization, C.Z., I-C.R. and B.G.; methodology, I-C.R., B.G. and C.Z.; validation, I-C.R., B.G. and C.Z.; formal analysis, A.-C.I.M. and I-C.R.; investigation, I-C.R., A.-C.I.M., A.H., B.G. and E.T.; writing--original draft preparation, A.-C.I.M. and I-C.R.; writing--review and editing, C.Z., B.G. and H.I.; supervision, C.Z. and H.I.; funding acquisition, I-C.R. All authors have read and agreed to the published version of the manuscript.  
This work was supported by a grant of the Ministry of Research, Innovation and Digitization, CNCS-UEFISCDI, project number PN-III-P1-1.1-PD-2021-0478, within PNCDI III.  
The data presented in this study are available on request from the corresponding author.  
This work has been supported by the European Social Fund from the Sectoral Operational Programme Human Capital 2014-2020 through the Financial Agreement with the title \"Training of PhD students and postdoctoral researchers in order to acquire applied research skills-SMART\", Contract no. 13530/16.06.2022-SMIS code: 153734. DLS was possible due to European Regional Development Fund through Competitiveness Operational Program 2014-2020, priority axis 1, Project No. P.36_611, MyMSMS code 107066, Innovative Technologies for Materials Quality Assurance in Health, Energy and Environmental-Center for Innovative Manufacturing Solutions of Smart Biomaterials and Biomedical Surfaces-INOVABIOMED.  
The authors declare no conflict of interest. The funders had no role in the design of this study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.