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Mono-dispersed mesoporous hollow carbon (MHC) nanospheres with comparable structures have been designed as nanocarriers for the delivery of vancomycin (Van) to inhibit bacterial growth. It is demonstrated that MHC materials possess a Van loading capacity of 861 mg g−1, much higher than that of any Van nanocarrier in previous reports. By comparing the drug loading, release and antibacterial performance of MHC nanospheres with controllable structures, it is shown that MHC with a pore size of 5.8 nm and a wall thickness of 25 nm exhibits compromising storage–release behaviour and achieves extended bactericidal activity of Van towards E. coli and S. epidermidis compared to free Van and other MHC nanocarriers. This study provides new knowledge about the rational design of carbon based nanocarriers to enhance the therapeutic efficacy of antibiotics.

Significant growing on environmental awareness has led researchers to study the surface functionalisation of cellulose nanofiber using natural renewable resources. This study aims to improve the percentage swelling of microfibrillated cellulose (MFC) of cocoa pod husks, crops-by product with Ƴ- methacryloxypropyltrimethoxysilane (MPS). Investigation on the effect of cocoa pod husk (CPH) microfibrillated cellulose (MFC-CPH) amount, MPS amount, MPS concentration and the reaction time to the percentage of swelling property of MFC-CPH treated with MPS was carried out. Composition amount of CPH -MFC, MPS, MPS concentration and the reaction time were varied from range of 0.5-6 gram, 1-9 mL, 5-15 w/w % and 2-24 hours respectively. Based on evaluation of percentage swelling obtained, it showed that the surface hydrophobicity of MFC-CPH treated with MPS could be increased due to the chemical bonds interaction that formed during silane treatment. The lowest percentage swelling of treated MFC-CPH-MPS is 14.96 % and the highest is 94.87 %. The untreated and treated MFC-CPH were then observed using fourier transform infrared (FT-IR) and field emission scanning electron microscopy (FESEM) for any change of structural and morphology. FT-IR results shows that there is reduction of OH groups in cellulose and addition of Si groups after silane treatment. There is also a change on the surface of MFC-CPH fibers after silane treatment as MFC-CPH fibers surface become rough due to deposited of MPS on MFC-CPH fibers.

The delivery of bactericidal proteins into biofilms is challenging. Hollow mesoporous silica nanoparticles with large cone-shaped pores were synthesized to deliver antimicrobial proteins into biofilms and showed enhanced antimicrobial activities.

Engineered magnetic iron oxide nanoparticles with surprisingly high antimicrobial activity and excellent safety profiles to mammalian cell lines have been developed. Hematite hollow nanospheres (HNSs) are prepared by a facile hard templating method; reduction of hematite HNSs by H-2 leads to magnetite HNSs. The antimicrobial activity of magnetite HNSs towards Gram negative (Escherichia coli) and Gram positive (Staphylococcus epidermidis) bacteria is evaluated against hematite HNSs and conventional magnetite (C-magnetite; diameter

Nature's creations with spiky topological features typically exhibit intriguing surface adhesive properties. From micrometer-sized pollen grains that can easily stick to hairy insects for pollination to nanoscale virus particles that are highly infectious toward host cells, multivalent interactions are formed taking advantage of rough surfaces. Herein, this nature-inspired concept is employed to develop novel drug delivery nanocarriers for antimicrobial applications. A facile new approach is developed to fabricate silica nanopollens (mesoporous silica nanospheres with rough surfaces), which show enhanced adhesion toward bacteria surfaces compared to their counterparts with smooth surfaces. Lysozyme, a natural antimicrobial enzyme, is loaded into silica nanopollens and shows sustained release behavior, potent antimicrobial activity, and long-term total bacterial inhibition up to 3 days toward Escherichia coli. The potent antibacterial activity of lysozyme-loaded silica nanopollens is further demonstrated ex vivo by using a small-intestine infection model. Our strategy provides a novel pathway in the rational design of nanocarriers for efficient drug delivery.

The abuse of antibiotics has led to the emergence of antibiotic resistant bacteria and high threats to human health. The search for safe and effective alternatives to traditional antibiotics is growing worldwide. In this article, we report the synthesis of large pore dendritic mesoporous silica nanoparticles (DMSNs) with controllable particle sizes and investigate the relationship between the particle size of DMSNs and their antibacterial enzyme delivery performance. The choice of dual-functional perfluorocarbon anions with both low surface tension and interaction with cationic surfactants enables the synthesis of DMSNs with tunable particle size and pore size. After loading with lysozyme, a naturally occurring antimicrobial enzyme, DMSNs with a large pore size of 22.4 nm and a small particle size of 79 nm show significantly better antibacterial activity compared to either DMSNs with a larger particle size (160 nm) or MSNs with a smaller pore size (2.4 nm) while the other parameter is similar. The optimized DMSNs loaded with lysozyme exhibit total inhibition towards Escherichia coli (E. coli) throughout five days. Our study provides new insights into the controllable synthesis of nano-carriers for antimicrobial protein delivery applications.

This study aims to investigate the effect of tin (Sn) and magnesium (Mg) on the sintering response of sintered Al. Although this topic has been extensively reported, details on the combined effect of Sn and Mg that function as sintering additives are still limited. The current study discusses the effect of the combined use of Sn and Mg to assist aluminium (Al) in liquid phase sintering via the powder metallurgy technique. The results demonstrated that the densities of sintered Al increased from 2.5397 to 2.575 g/cm3 as the Sn content increased from 1.5 to 2.5 wt. % respectively. Accordingly, the physical characteristics of sintered Al were transformed from black to silver, which confirmed the reduction in the oxygen content (oxide layer reduction) from 0.58 to 0.44 wt. % respectively. Additionally, the microstructure of the resultant sintered Al demonstrated that effective wetting by Sn addition was obtained at its maximum content of 2.5 wt. % with a greater micro pores reduction and better metallurgical bonding between Al particles. Therefore, the introduction of different Sn content, along with Mg element, was found to further improve the sintering response of the resultant sintered Al that consequently improved its densities and physical characteristics.