Preparation of Janus‐type superparamagnetic iron oxide nanoparticles modified with functionalized PCL / PHEMA via photopolymerization for dual drug delivery

Synthesis and performance analysis of novel SiO2 Janus nanoparticles for enhancing gas foam injection in oil reservoirs

Gas foam injection offers a viable solution to challenges faced in oil reservoirs, yet ensuring optimal foamability and stability remains a pivotal hurdle in practical field operations. This study presents a novel synthesis procedure to create silica (SiO2) Janus nanoparticles (JNPs) and examines their potential to enhance gas foam stability for enhanced oil recovery (EOR) applications. Two variations of SiO2 JNPs were synthesized via a masking procedure, employing oleic acid and ascorbic acid within a Pickering emulsion, marking a pioneering approach. These nanoparticles underwent comprehensive analysis for a deeper understanding. The investigation sought to unravel the mechanisms behind these JNPs' performance in the foam injection process, probing various operational parameters such as JNP type, concentration, and gas medium (air, CO2, and CH4) impact on surface tension reduction, foamability, and stability through static tests. Results uncovered remarkable efficiency in SiO2-oleic acid JNPs, showcasing a substantial edge in reducing surface tension compared to bare SiO2 nanoparticles. Specifically, at a concentration of 15,000 ppm, SiO2-oleic acid JNPs demonstrated a 25 mN/m greater reduction in surface tension than bare SiO2 within a CH4 medium. Notably, while the gas type had limited influence on surface tension under standard pressure, the synthesized JNPs showed superior foam stabilization in air compared to CO2 and CH4 environments. SiO2-oleic JNPs exhibited outstanding foamability, stabilizing 80% of the foam generator cell's height and remaining stable for 122 min during the EOR process. Conversely, ascorbic acid-SiO2-oleic acid JNPs displayed elevated foamability but reduced stability compared to SiO2-oleic acid JNPs. Despite achieving full height in the foam generator cell, stability was limited to 26 min in the CO2 medium.

Magnetite-based Janus nanoparticles, their synthesis and biomedical applications

The advent of Janus nanoparticles has been a great breakthrough in the emerging field of nanomaterials. Janus nanoparticles refer to a single structure with two distinct chemical functions on either side. Owing to their asymmetric structures, they can be utilized in a variety of applications where monomorphic particles are insufficient. In the last decade, a wide variety of materials have been employed to fabricate Janus nanoparticles, and due to the great advantages of magnetite (Iron-oxide) NPs, they have been considered as one of the best candidates. With the main benefit of magnetic controlling, magnetite Janus nanoparticles fulfill great promises, especially in biomedical areas such as bioimaging, cancer therapies, theranostics, and biosensing. The intrinsic characteristics of magnetite Janus nanoparticles (MJNPs) even hold great potential in magnetite Janus forms of micro-/nanomotors. Despite the great interest and potential in magnetic Janus NPs, the need for a comprehensive review on MJNPs with a concentration on magnetite NPs has been overlooked. Herein, we present recent advancements in the magnetite-based Janus nanoparticles in the flourishing field of biomedicine. First, the synthesis and fabrication methods of Janus nanoparticles are discussed. Then we will delve into their intriguing biomedical applications, with a separate section for magnetite Janus micro-/nanomotors in biomedicine. And finally, the challenges and future outlook are provided. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Diagnostic Tools > Diagnostic Nanodevices Diagnostic Tools > In Vitro Nanoparticle-Based Sensing.

Utilization of synthesized silane-based silica Janus nanoparticles to improve foam stability applicable in oil production: static study

This study investigated the effect of silane-based silica (SiO2) Janus nanoparticles (JNPs) on stabilizing the foam generated by different types of gases. Two types of SiO2 JNPs were synthesized through surface modification using HMDS and APTS silane compounds. Static analyses were conducted to examine the impact of different concentrations of the synthesized nanoparticles in various atmospheres (air, CO2, and CH4) on surface tension, foamability, and foam stability. The results indicated that the synthesized SiO2 JNPs and bare SiO2 nanoparticles exhibited nearly the same ability to reduce surface tension at ambient temperature and pressure. Both of these nanoparticles reduced the surface tension from 71 to 58-59 mN m-1 at 15,000 ppm and 25 °C. While bare SiO2 nanoparticles exhibited no foamability, the synthesis of SiO2 JNPs significantly enhanced their ability to generate and stabilize gas foam. The foamability of HMDS-SiO2 JNPs started at a higher concentration than APTS-SiO2 JNPs (6000 ppm compared to 4000 ppm, respectively). The type of gas atmosphere played a crucial role in the efficiency of the synthesized JNPs. In a CH4 medium, the foamability of synthesized JNPs was superior to that in air and CO2. At a concentration of 1500 ppm in a CH4 medium, HMDS-SiO2 and APTS-SiO2 JNPs could stabilize the generated foam for 36 and 12 min, respectively. Due to the very low dissolution of CO2 gas in water at ambient pressure, the potential of synthesized JNPs decreased in this medium. Finally, it was found that HMDS-SiO2 JNPs exhibited better foamability and foam stability in all gas mediums compared to APTS-SiO2 JNPs for use in oil reservoirs. Also, the optimal performance of these JNPs was observed at a concentration of 15,000 ppm in a methane gas medium.