Recent advances in materials science: a reinforced approach toward challenges against COVID-19.

With the recent COVID-19 pandemic, medical professionals and scientists have encountered an unprecedented trouble to make the latest technological solutions to work. Despite of abundant tools available as well as initiated for diagnosis and treatment, researchers in the healthcare systems were in backfoot to provide concrete answers to the demanding challenge of SARS-CoV-2. It has incited global collaborative efforts in every field from economic, social, and political to dedicated science to confront the growing demand toward solution to this outbreak. Field of materials science has been in the frontline to the current scenario to provide major diagnostic tools, antiviral materials, safety materials, and various therapeutic means such as, antiviral drug design, drug delivery, and vaccination. In the present article, we emphasized the role of materials science to the development of PPE kits such as protecting suits, gloves, and masks as well as disinfection of the surfaces/surroundings. In addition, contribution of materials science towards manufacturing diagnostic devices such as microfluidics, immunosensors as well as biomaterials with a point of care analysis has also been discussed. Further, the efficacy of nanoparticles and scaffolds for antiviral drug delivery and micro-physiological systems as well as materials derived from human tissues for extracorporeal membrane oxygenation (ECMO) devices have been elaborated towards therapeutic applications.

Improved antibacterial and cellular response of electrets and piezobioceramics.

The bacterial contamination in implants has been recognized as one of the key issues in orthopedics. In this article, a new technique of electrical polarization of various non-piezoelectric and piezoelectric biocompatible ceramics has been explored to develop antibacterial implants. Optimally processed hydroxyapatite (HA), BaTiO3 (BT), CaTiO3 (CT), Na0.5K0.5NbO3 (NKN) and their composites have been used as model biomaterials to verify the concept. The phase evolution analyses and microstructural characterizations were performed for sintered samples. The samples were polarized at polarizing voltage and temperature of 20 kV and 500°C, respectively, for 30 min. The hydrophilicity of polarized surfaces was examined using deionized water and culture media. The polarization induced in-vitro antibacterial study was performed for both, gram positive and gram negative bacteria. The viability of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacteria reduces significantly on the polarized surfaces. In addition, the influence of polarization on antibacterial response has been explored via various mechanisms such as development of reactive oxygen species (ROS), catalase activity and lipoperoxidation. Furthermore, the cellular response of polarized surfaces was also examined using SaOS2 and MG-63 cells. The viability of SaOS2 and MG-63 cells was observed to increase significantly on negatively polarized surfaces. Overall, the surface treatment enhances the antibacterial response of HA, NKN, BT, CT and their composites surfaces with positive influence on cellular response.

Effect of pre-existing diseases on COVID-19 infection and role of new sensors and biomaterials for its detection and treatment.

The entire world is suffering from a new type of viral disease, occurred by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The present article briefly discussed the genome sequencing and interaction of host cells with SARS-CoV-2. The influence of pre-existing diseases such as diabetes, heart disease and age of the patients on COVID-19 infection is reviewed. The possible treatments of SARS-CoV-2 including antiviral drugs, Chinese traditional treatment and plasma therapy are elaborately discussed. The proper vaccine for COVID-19 is not available till date. However, the trials of pre-existing antiviral vaccines such as, chloroquine/hydroxychloroquine, remdesivir, ritonavir and lopinavir and their consequences are briefly presented. Further, the importance of new materials and devices for the detection and treatment of COVID-19 has also been reviewed. The polymerase chain reaction (PCR)-based, and non-PCR based devices are used for the detection of COVID-19 infection. The non-PCR based devices provide rapid results as compared to PCR based devices.

Electro-mechanical and Polarization-Induced Antibacterial Response of 45S5 Bioglass-Sodium Potassium Niobate Piezoelectric Ceramic Composites.

Besides the excellent osteoconductivity and biocompatibility of 45S5 bioglass (BG), poor mechanical and electrical properties as well as susceptibility toward bacterial adhesion limit its widespread clinical applications. In this context, the present study investigates the effect of addition of piezoelectric sodium potassium niobate (Na0.5K0.5NbO3; NKN) on mechanical, dielectric, and antibacterial response of BG. BG-xNKN (x = 0, 10, 20, and 30 vol%) composites were synthesized at 800 °C for 30 min. The phase analyses using spectral techniques revealed the formation of the composite without any reaction between BG and piezoelectric ceramic NKN. The dielectric and electrical measurements were performed over a wide range of temperature (30-500 °C) and frequency (1 Hz-1 MHz) which suggests that space charge and dipolar polarizations are the dominant polarization mechanisms. The complex impedance analyses suggest that the average activation energies for grain and grain boundary resistances for BG-xNKN (x = 10, 20, and 30 vol%) composites are 0.59, 0.87, 0.94 and 0.76, 0.93, 1.06 eV, respectively. The issue of bacterial infection has been addressed by electrical polarization of the developed composite samples, at 20 kV for 30 min. Statistical analyses reveal that the viability of Gram-positive (S. aureus) and Gram-negative (E. coli) bacterial cells has been reduced significantly on positively and negatively charged BG-NKN composite samples, respectively. The qualitative analyses using the Kirby-Bauer test supports the above findings. Nitro blue tetrazolium and lipid peroxide assays were performed to understand the mechanism of such antibacterial response, which suggested that the combined effect of NKN addition and polarization significantly enhances the superoxide production, which kills the bacterial cells. Overall, incorporation of NKN in BG enhances the mechanical, electrical, and dielectric properties as well as improves the antibacterial response of polarized BG-xNKN composites.

Combined effect of surface polarization and ZnO addition on antibacterial and cellular response of Hydroxyapatite-ZnO composites.

Bacterial infection is among the serious concerns in orthopaedic during/after surgery. Here, we demonstrate a novel technique to induce the antibacterial response in biomaterial substrates via surface polarization. In the present work, hydroxyapatite, HA-xZnO (x = 3.0, 4.5 and 7.5 wt. %) composites were processed by solid state sintering route at 1250 °C for 2 h. After phase evolution analyses, the detailed dielectric and electrical measurements were performed over a wide range of temperature (30-500 °C) and frequency (1 Hz-1 MHz). The impedance spectroscopic analyses suggest the activation energies for grains and grain boundaries for HA and HA-3 wt.% ZnO are (1.36, 1.44 eV), and (1.18, 1.98 eV), respectively. The sintered samples were polarized under polarizing temperature and voltage of 500 °C and 20 kV, respectively. The viability of Escherichia Coli (E. Coli) and Staphylococcus Aureus (S. Aureus) bacteria is observed to reduce significantly for polarized HA-x ZnO (x = 4.5 and 7.5 wt. %) composites as compared to their respective counterparts. On the other hand, polarization supports the proliferation of SaOS2 cells. Overall, the combination of surface polarization and optimal ZnO addition in HA has been demonstrated to significantly improve the antibacterial as well as osteoblast-like SaOS2 cellular response.