Bone cement has found extensive usage in joint arthroplasty over the last 50 years; still, the development of bone cement with essential properties such as high fatigue resistance, lower exothermic temperature, and bioactivity has been an unsolved problem. In our present work, we have addressed all of the mentioned shortcomings of bone cement by reinforcing it with graphene (GR), graphene oxide (GO), and surface-modified amino graphene (AG) fillers. These nanocomposites have shown hypsochromic shifts, suggesting strong interactions between the filler material and the polymer matrix. AG-based nanohybrids have shown greater osteointegration and lower cytotoxicity compared to other nanohybrids as well as pristine bone cement. They have also reduced oxidative stress on cells, resulting in calcification within 20 days of the implantation of nanohybrids into the rabbits. They have significantly reduced the exothermic curing temperature to body temperature and increased the setting time to facilitate practitioners, suggesting that reaction temperature and settling time can be dynamically controlled by varying the concentration of the filler. Thermal stability and enhanced mechanical properties have been achieved in nanohybrids vis-à-vis pure bone cement. Thus, this newly developed nanocomposite can create natural bonding with bone tissues for improved bioactivity, longer sustainability, and better strength in the prosthesis.

Nowadays necessities for the green synthesis of nanoparticles are enlarged because of its neutral toxicity and eco-friendly advantages. In this present study, we have explored the rapid biosynthesis of AgNPs at room temperature by the fresh leaf aqueous extract of Anacardium occidentale. Aqueous extracts were prepared at different temperatures 60, 80 and 100°C. Formation of silver nanoparticles (AgNPs) was confirmed by surface plasmon resonance (SPR) peak observed around 400-420 nm in UV-Visible spectra. Among the extracts prepared, 80°C extract showed good shift in UV-Visible spectrum during Cr(VI) detection and a good linear relationship was found between the absorbance ratio (A 510 /A 400 ) against 100 mM-1 lM concentration of Cr(VI). Cr(VI) was confirmed by the red shift of SPR position from 400 to 510 nm. Detection limit of our prepared probe is 1 lM and this simple technique exhibiting high selectivity to Cr(VI) over other tested heavy metal ions. Finally, efficient 80°C extract synthesized AgNPs were characterized by XRD, SEM and TEM. XRD characterization confirmed its face centered cubic structure and confirmed that the prepared AgNPs are crystalline in nature. TEM and SEM characterization results revealed that the AgNPs are in spherical nature. The size of AgNPs was found to be 40-60 nm.

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Biodegradable poly(lactic acid) (PLA) is widely used to fabricate 3D scaffolds for tissue regeneration. However, PLA lacks cell adhering functional moieties, which limit its successful application in tissue engineering. Herein, we have tailored the cell adhesive properties of star shaped poly(d,l-lactide) (ss-PDLLA) by grafting gelatin to their 4 arms. Grafting of gelatin on PDLLA backbone was confirmed by H NMR and FTIR. The synthesized star shaped poly(d,l-lactide)-b-gelatin (ss-pLG) exhibited enhanced wettability and protein adsorption. The modification also facilitated better cell adhesion and proliferation on their respective polymer coated 2D substrates, compared to their respective unmodified ss-PDLLA. Further, 3D scaffolds were fabricated from gelatin grafted and unmodified polymers. The fabricated scaffolds were shown to be cytocompatible to 3T3-L1 cells and hemocompatible to red blood cells (RBCs). Cell proliferation was increased up to 2.5-fold in ss-pLG scaffolds compared to ss-PDLLA scaffolds. Furthermore, a significant increase in cell number reveals a high degree of infiltration of cells into the scaffolds, forming a viable and healthy 3D interconnected cell community. In addition to that, burst release of docetaxal (DTX) was observed from ss-pLG scaffolds. Hence, this new system of grafting polymers followed by fabricating 3D scaffolds could be utilized as a successful approach in a variety of applications where cell-containing depots are used.

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