Performance of environmentally friendly silica nanoparticles-enhanced drilling mud from sugarcane bagasse

Silica/Annona muricata nano-hybrid: Synthesis and anticancer activity against breast cancer

Biogenically derived silica nanoparticles may serve as a well-defined target vehicle for drug delivery and have a wide range of applications in biomedicine. Silica nanoparticles are an excellent candidate as drug carriers due to their mesoporous structure, high drug loading capacity, low toxicity, environmental friendliness and low economic synthesis procedures. In this study, nano structured silica was extracted from sugarcane bagasse through an alkali leaching extraction and conjugated with A. muricata extract overcoming its poor solubility and improving its bioavailability within the host system. The Silica Nanoparticles (SNP) and Annona muricata conjugated Silica Nanoparticles (AM/SNP) were characterized using SEM, FTIR, TGA, EDAX, XRD and zeta potential. The AM/SNP was subjected to kinetic release studies and exhibited a sustained release of 64 % over the course of 12 h in contrast to extract, indicating the slow release of the drug under synthetic conditions. A. muricata pose a high affinity against tumor cells as an anti-cancer agent, and the potential of binding was testified using in-silico virtual screening against breast cancer receptors with lead acetogenins with Annomuricin (-7.4 kcal/mol) and Gigantecin (-7.4 kcal/mol) exhibiting a high binding affinity against ER and HER2+ receptors respectively. The AM/SNP conjugate exhibited high cytotoxicity against the MCF-7 breast cancer cell line with an IC50 value of 33.43 μg, indicating high potency of the conjugate at low concentrations, facilitating low systemic toxicity on administration.

Synergetic Effects of Graphene Nanoplatelets/Tapioca Starch on Water-Based Drilling Muds: Enhancements in Rheological and Filtration Characteristics

Several borehole problems are encountered during drilling a well due to improper mud design. These problems are directly associated with the rheological and filtration properties of the fluid used during drilling. Thus, it is important to investigate the mud rheological and filtration characteristics of water-based drilling muds (WBMs). Several materials have been examined but due to the higher temperature conditions of wells, such materials have degraded and lost their primary functions. In this research, an attempt was made to prepare a water-based mud by utilizing graphene nano platelets (GNP) in addition to the native tapioca starch at different ratios. The combined effect of starch and graphene nano platelets has been investigated in terms of mud’s rheological and filtration parameters, including its plastic viscosity (PV), yield point (YP), fluid loss volume (FLV) and filtercake thickness (FCT). The morphological changes in the filtercake have also been observed using Field Emission Scanning Electron Microscope (FESEM) micrographs. Plastic viscosity was increased from 18–35 cP, 22–31 cP and 21–28 cP for 68 °F, 250 °F and 300 °F, respectively. The yield point was also enhanced from 22–37 lb/100ft², 26–41 lb/100ft² and 24–31 lb/100ft² at the studied range. The fluid loss was dramatically reduced from 14.5–6.5 mL, 17.3–7.5 mL and 36–9.5 mL at 68 °F, 250 °F and 300 °F respectively. Similarly, filtercake thickness was also reduced which was further illustrated by filtercake morphology.

A Novel Amphoteric Polymer as a Rheology Enhancer and Fluid-Loss Control Agent for Water-Based Drilling Muds at Elevated Temperatures

Exploring deep and ultradeep wells has rapidly become more significant to meet the global demand for oil and gas. The study of rheological and filtration-loss properties is essential to designing drilling muds and determining their performance under operational conditions. Rheological and filtration-loss properties of drilling muds were found to have a negative impact when exposed to elevated temperatures in the wells. In this study, an amphoteric polymer (abbreviated to PEX) was synthesized and characterized using a combination of analyses: FTIR, SEM, 13CNMR, and TGA. The synthesized PEX was used as an additive in water-based drilling muds to improve rheological properties and reduce fluid loss at elevated temperatures (180-220 °C). The experimental results demonstrated that inclusion of an optimal concentration of PEX (0.3 wt %) into the drilling mud formulation increased the rheological properties by 62.3% and decreased the filtration loss by 63.5% at an aging temperature of 180 °C. Moreover, PEX was found to perform superbly compared to polyanionic cellulose (PAC-LV) and polyacrylamide (PAM), the widely used drilling mud additives. PEX not only improved the rheological properties and reduced the filtration loss behavior but also bolstered the thermostability of the drilling mud formulation. It was concluded that the rigidity and amphoteric nature of PEX accounted for the exceptional performance and temperature resistance for PEX-drilling mud formulations. Succinctly, PEX exhibits admirable properties in smart drilling mud formulations for drilling operations under high-temperature geothermal conditions. Moreover, in terms of rheological models, the Herschel-Bulkley model adequately described the rheological properties of all the studied drilling mud formulations.