Effective gene delivery using size dependant nano core-shell in human cervical cancer cell lines by magnetofection

PLOS ONE RESEARCH ARTICLE Effective gene delivery using size dependant nano core-shell in human cervical cancer cell lines by magnetofection Srinivasa Sundara Rajan R.1, Jobin Thomas1,2, Dileep Francis1, Elcey C. Daniel ID1* 1 Biotechnology Research Centre, Kristu Jayanti College (Autonomous), Bengaluru, Karnataka, India, 2 Centre for Nano Bbiotechnology (CNBT), Vellore Institute of Technology, Vellore, Tamil Nadu, India * Abstract a1111111111 a1111111111 a1111111111 a1111111111 a1111111111 OPEN ACCESS Citation: Sundara Rajan R. S, Thomas J, Francis D, Daniel EC (2023) Effective gene delivery using size dependant nano core-shell in human cervical cancer cell lines by magnetofection. PLoS ONE 18(9): e0289731. https://doi.org/10.1371/journal. pone.0289731 Editor: Amitava Mukherjee, VIT University, INDIA Received: November 5, 2022 Biocompatible magnetic nanoparticles are effective for gene delivery in vitro and in vivo transfection. These mediators are mainly used to deliver drugs and genes. It can also be used as probes to diagnose and treat various diseases. Magnetic nanoparticles, primarily iron oxide nanoparticles, are used in various biological applications. However, preparing stable and small-size biocompatible core-shell is crucial in site direct gene delivery. In the present study, superparamagnetic iron oxide nanoparticles were synthesized using the chemical co-precipitation method and were functionalized with starch to attain stable particles. These SPIONs were coated with polyethylenimine to give a net positive charge. The fluorescent plasmid DNA bound to the SPIONs were used as a core shell for gene delivery into the HeLa cells via magnetofection. UV-Visible Spectrophotometry analysis showed a peak at 200 nm, which confirms the presence of FeO nanoparticles. The Scanning Electron Microscopy images revealed the formation of spherical-shaped nanoparticles with an average size of 10 nm. Xray Diffraction also confirmed FeO as a significant constituent element. Vibrating Sample Magnetometry ensures that the nanoparticles are superparamagnetic. Atomic Force Microscopy images show the DNA bound on the surface of the nanoparticles. The gene delivery and transfection efficiency were analyzed by flow cytometry. These nanoparticles could effectively compact the pDNA, allowing efficient gene transfer into the HeLa cell lines. Accepted: July 25, 2023 Published: September 7, 2023 Copyright: © 2023 Sundara Rajan R. et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All relevant data are within the paper. Funding: The author(s) received no specific funding for this work. Competing interests: The authors have declared that no competing interests exist. Introduction The recent development of nonviral transfection agents for gene delivery has given rise to high efficiency. Gene therapy is the latest technique to treat various genetic disorders. Introducing the desired gene, alters defective genes and restores normal metabolism. Magnetic nanoparticles have been used as an efficient carrier in delivering specific therapeutic agents, which are attached or encapsulated within a magnetic nanoparticle. Magnetic nanoparticles composed of an iron oxide core and polymeric shell present an exceptional carrier for gene delivery of nucleic acids. The high magnetic property of the iron oxide core enables the non-invasive administration of magnetic nanoparticles by magnetic fields. The nanoparticle’s surface is responsible for interaction with the drug and host. PLOS ONE | https://doi.org/10.1371/journal.pone.0289731 September 7, 2023 1 / 18 PLOS ONE Gene delivery using size dependant nano core-shell in human cervical cancer cell lines by magnetofection Many methods have been developed for synthesizing iron oxide nanoparticles (NPs), where one can control its shape, stability, biocompatible and monodispersed iron oxide NPs. The most common method includes co-precipitation and thermal decomposition. Other methods include hydrothermal synthesis, microemulsion, and sonochemical synthesis [1]. Co-precipitation is the best method for obtaining Fe3O4 and γ-Fe2O3 [2]. The iron oxide Nanoparticle’s surface has to be functionalized with a suitable stabilizer to prevent agglomeration and to obtain a stable colloidal solution. Surfactants aid in controlling the particle size and stabilizing the colloidal dispersions [1]. Starch, a branched hydrophilic long-chain polymer of D-glucose, is being used as a drug carrier due to its biocompatibility, nontoxicity, and biodegradability [3]. When starch is combined with colloidal particles, the magnetic stability rises to various applications, such as gene delivery, drug delivery, magnetic resonance imaging, and tissue engineering. Due to its neutral free hydroxyl functional groups, it can bind to diverse chemical groups and ions and enhance surface activity [4, 5]. The coating of iron oxide NPs with polymers has recently received more attention. Polymer coating will increase repulsive forces to balance the magnetic and the Van der Waals attractive forces acting on the NPs. Natural polymers like dextran, starch, chitosan, or synthetic polymers like polyethylene glycol (PEG), polymethylmethacrylate (PMMA), and polyethylenimine (PEI) can be utilized, which are biocompatible. Size control, high encapsulation efficiency, and sustained release behaviour of the anticancer drug are shown by biodegradable polymer Nanoparticles [6]. PEI is the most widely used biopolymer agent capable of forming complexes with DNA, condensing them into compact nanoparticles, and protecting DNA against degradation [7]. Based on their high surface charge, PEIs are promising candidates for the delivery of negatively charged nucleic acids. PEI attached to nanoparticle surfaces through covalent and electrostatic interactions achieves the goal [8]. The transfection capability and cytotoxicity effect depend on the molecular weight and structure of PEIs [6]. The “proton sponge effect” is responsible for their high transfection efficiency. This property is thought to lead to buffering inside endosomes. The osmotic swelling and physical rupture of the endosomes are due to the pumping of protons into the endosomes, which helps escape vectors from the degradative lysosomal pathway [9]. A lower concentration of PEI needs to be used to reduce its toxicity for the effective core shell [10]. Magnetofection combines nucleic acid and its vector with magnetic nanoparticles, so they can be drawn and concentrated to the target cells by applying a magnetic field. This technique enhances the efficiency up to several hundred folds and can reduce the process from 4 h to 15 min. This process requires magnetic nanoparticles to be surface functionalized to couple with the gene complexe (...truncated)