Apoptotic Induction by Biosynthesized Gold Nanoparticles Using <i>Phormidesmis communis</i> Strain AB_11_10 against Osteosarcoma Cancer

Phormidesmis communis strain AB_11_10 was isolated and identified using microscopy and 16s rRNA sequencing, and its phytochemical constituents were determined using liquid chromatography-quadrupole time-of-flight mass spectrometry. The isolate had a segmented filamentous shape with a blue-green color. Many biomolecules, including organic compounds, amino acids, and fatty acids, were detected. P. communis strain AB_11_10 was used to synthesize gold nanoparticles (Ph-AuNPs) by adjusting the optimum reaction conditions. The concentration, algal/precursor ratio, temperature, reaction time, and pH significantly influenced the synthesis of the Ph-AuNPs. Mixing 1 mL of 0.5 mM of HAuCl4 with 1 mL of algal extract and exposing the mixture to 100 °C for 30 min at pH 5.6 were the optimum conditions for the biosynthesis of Ph-AuNPs at a wavelength of 524.5 nm. The Ph-AuNPs were characterized using TEM, SEM, EDX, and mapping Zeta sizer and FTIR. The Ph-AuNPs had quasi-spherical to triangular shapes with an average diameter of 9.6 ± 4.3 nm. Ph-AuNPs composed of 76.10 ± 3.14% of Au and trace amounts of carbon and oxygen were detected, indicating that the P. communis strain AB_11_10 successfully synthesized Ph-AuNPs. The hydrodynamic diameter of the Ph-AuNPs was 28.5 nm, and their potential charge was −17.7 mV. O-H, N-H, C=C, N-O, C-H, and C-O were coated onto the surfaces of the Ph-AuNPs. These groups correspond to algal phytochemicals, which may have been the main reducing and stabilizing substances during the Ph-AuNP synthesis. The therapeutic activity of the Ph-AuNPs against osteosarcoma cancers was examined in MG-63 and SAOS-2 cell lines, while their biocompatibility was tested against Vero cell lines using a sulforhodamine B assay. The Ph-AuNPs had potent antitumor activity against the MG-63 and SAOS-2 cells, with a low toxicity toward Vero cells. Flow cytometry and cell cycle arrest analyses revealed that the Ph-AuNPs enhanced the apoptotic pathway and arrested the cell cycle in the MG-63 and SAOS-2 cells. P. communis strain AB_11_10 provides a new source to synthesize small, stable, and biocompatible AuNPs that act as apoptotic enhancers in osteosarcoma

Hydrophilic and hydrophobic materials and their applications

Wettability of a material’s surface plays a significant role in how fluids interact with such surfaces. Wetting behaviour is universal but can vary depending on the chemical nature of the solid and liquid phases. Plants and animals adapt to their environment through having evolved special properties. These properties are such as hydrophilic and hydrophobic. Hydrophilic surface has a strong affinity to water and spreading of water on such surface is preferred. The degree of hydrophilicity of the substance can be measured by measuring the contact angle between the liquid and solid phases. Hydrophobic materials are known as non-polar materials with a low affinity to water, which makes them water repelling. A contact angle of less than 90° indicates hydrophilic interaction where as an angle greater than 90° indicates a hydrophobic interaction. More recently, superwetting such as superhydrophilicity has been receiving an increased focus in literature due to its potential significance. Superhydrophilic surface has a contact angle of less than 5°. The fabrication of hydrophilic materials can be carried out in two main ways: depositing molecules on surfaces or modification of surface chemistry. Both methods have been successful historically in achieving their intended purposes. Hydrophobic and superhydrophobic materials can be produced with many fabrication methods such as layer-by-layer assembly, laser process, the solution-immersion method, sol-gen techniques, chemical etching and Hummer’s method. The applications of such an important property are significant. For example, hydrophilic surfaces can be used in anti-fogging applications, biomedical, filtration, heat pipes, and many others. Hydrophobic and superhydrophobic materials have been successfully applied in many sectors, such as: (I) the removal of petroleum from aqueous solutions, (II) applied to plastic, ceramics and mesh to contribute to the oil removal from aqueous solutions, (III) hydrophobic layers have a strong self-cleaning effect on plastics, heat pipes, metals, textiles, glass, paints and electronics, (IV) hydrophobic layers improve the anti-freezing behaviour of heat pipes which prevents unwanted build-up and (V) they function as a water and dust protecting coat on electronics The presence of this property is historic but there is still a huge potential for development for its applications in many sectors such as water treatment, heat transfer applications, biomedical devices, and many more