Multifunctional surface functionalized magnetic iron oxide nanoparticles for biomedical applications: A review

Magnetic iron oxide nanoparticle-based multifunctional platforms have been explored extensively in biomedical applications. Modifications and integrations of IONPs with different entities viz. organic polymer, doping with inorganic materials, loading with drug, fluorescent dye, or antibodies make them appropriate for their application in broad spectrum of biomedical fields. This review presents and summarizes the fabrication strategies of multifunctional magnetic nanoparticles based on the modification and surface functionalization of MNP. Multifunctional IONPs based recent advances covering a wide array of applications like biosensing and pathogen detection, magnetic resonance imaging (MRI) and biomarker tracking, magnetofection and gene therapy, hyperthermia and chemotherapy, drug delivery and targeted cell killing, bioimaging and therapeutics, stem cell detection and therapy, tissue engineering and organ transplant, nano-vaccines and immune system activation, microbe targeting and destruction, and COVID19 management are also covered.

pH-responsive glycine functionalized magnetic iron oxide nanoparticles for SARS-CoV-2 RNA extraction from clinical sample.

The recent outbreak of the novel corona virus disease 2019 (COVID-19) has been made a serious global impact due to its high infectivity and severe symptoms. The Severe Acute Respiratory Syndrome (SARS-CoV-2) RNA extraction is considered as one of the most important steps in COVID-19 detection. Several commercially available kits and techniques are currently being used for specific extraction of SARS-CoV-2 RNA. However, such methods are time consuming and expensive due to the requirement of trained labors, and several chemical reagents. To overcome the mentioned limitations, magnetic RNA adsorption methodology of glycine functionalized iron oxide nanoparticles (GNPs) was established. It showed an efficient potential in SARS-CoV-2 RNA extraction due to pH responsive nature of GNPs. The highly magnetic pH responsive GNPs were synthesized by one-pot co-precipitation method. Random morphology and average 20 nm size of GNPs were denoted by Transmission Electron Microscopy (TEM). X-ray diffractometer (XRD) showed the crystalline magnetite nature. Fourier transform infrared spectroscopy (FT-IR) and UV-visible spectrometry confirmed the presence of glycine on the surface of magnetic nanoparticles. Furthermore, the magnetic nature and thermal properties of GNPs were examined by vibrating sample magnetometer (VSM) and thermo-gravimetric analysis (TGA), respectively. In this study, glycine performed the role of RNA adsorbent. The adsorption of RNA onto the surface of GNPs was achieved in acidic medium (pH 6). In contrary, the elution of RNA from the surface of GNPs was achieved in basic medium (pH 8). The purity of obtained RNA was analyzed by UV-visible spectrometry. Further, the obtained RNA was examined for the presence of SARS-CoV-2 specific Envelope (E), RNA dependent RNA polymerase (RDRP) and Nucleocapsid (N) genes using an RT-PCR analysis. It showed the sudden rise in amount of these genes after 25 cycles of RT-PCR and hence indicated the efficient RNA extraction by GNPs. Agarose gel electrophoresis was used for validation of the quantity and quality of RNA extracted from SARS-CoV-2 patient's sample. The reusability studies of GNPs were performed by monitoring the repeated use of GNPs for SARS-CoV-2 RNA extraction. This method possesses potential role in the field of disease diagnosis. The extraction results of RNA from SARS-CoV-2 patient's sample indicated that the GNPs have an outstanding property over the current existing extraction protocols. It leads to the new advancements in extraction and detection of RNA. Graphical Abstract: Graphical abstract of the pH responsive SARS-CoV-2 RNA extraction by using glycine functionalized magnetic iron oxide nanoparticles (GNPs) which were prepared by modified cost effective one pot chemical synthesis method. Prepared GNPs were characterized by XRD, FT-IR and UV-Visible spectrometry, Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). Glycine present on the surface of nanoparticles (NPs) played an important role in pH responsive RNA extraction procedure. When nanoparticles added in acidic (pH < 7) medium, glycine gained positive surface charge hence overall surface charge of NPs became positive. Thereby SARS-CoV-2 RNA adsorption/binding occurred on the surface of GNP. Later, the RNA-GNP complex was separated by an external magnet. Separated complex was added in basic (pH > 7) medium to elute RNA from GNP. This phenomenon occurred due to surface negative charge of glycine that caused charge repulsion with RNA. Eluted RNA was examined qualitatively and quantitatively by RT-PCR, nanodrop technique and agarose gel electrophoresis. Results were compared with kit based extracted RNA. Supplementary Information: The online version contains supplementary material available at 10.1007/s10853-022-07464-6.

In silico molecular docking analysis for repurposing therapeutics against multiple proteins from SARS-CoV-2.

SARS-CoV-2 has devastated the world with its rapid spread and fatality. The researchers across the globe are struggling hard to search a drug to treat this infection. Understanding the time constraint, the best approach is to study clinically approved drugs for control of this deadly pandemic of COVID 19. The repurposing of such drugs can be supported with the study of molecular interactions to enhance the possibility of application. The present work is a molecular docking study of proteins responsible for viral propagation namely 3Clpro, Nsp10/16, Spike protein, SARS protein receptor binding domain, Nsp 9 viral single strand binding protein and viral helicase. The protein through virus enters the host cell-human angiotensin-converting enzyme 2 (ACE2) receptor, is also used as a target for molecular docking. The docking was done with most discussed drugs for SARS-CoV-2 like Ritonavir, Lopinavir, Remdesivir, Chloroquine, Hydroxychloroquine (HCQ), routine antiviral drugs like Oseltamivir and Ribavirin. In addition, small molecules with anti-inflammatory actions like Mycophenolic acid (MPA), Pemirolast, Isoniazid and Eriodictyol were also tested. The generated data confirms the potential of Ritonavir, Lopinavir and Remdesivir as a therapeutic candidate against SARS-CoV-2. It is observed that Eriodictyol binds to almost all selected target proteins with good binding energy, suggesting its importance in treatment of COVID 19. Molecular interactions of Ritonavir, Lopinavir and Remdesivir against SARS-CoV-2 proteins enhanced their potential as a candidate drug for treatment of COVID-19. Eriodictyol had emerged as a new repurposing drug that can be used in COVID-19.