Reversible packaging is very desirable for microfluidic chips: it allows changing the chip upper cap when it is damaged, cleaning and reusing the chip bottom substrate. This latter case becomes even more attractive when integrated components are present on the substrate and have required a complex and expensive microfabrication process. The feasibility of poly(dimethylsiloxane) (PDMS)/PDMS and PDMS/glass reversible bonding is demonstrated using the stamping technique. Dimethyl-methylphenylmethoxy siloxane (DMPMS), a type of silicone conformal coating, is used as an adhesive layer between the PDMS channel and the substrate (PDMS or glass). This technique is easy to perform as it only needs spin-coating and thermal curing steps. The bond strength is suitable for high working flow rate/pressure of liquid in the channel (up to 500 μl/min and 200 kPa). The cycle ‘pealing/bonding’ of the cap can be repeated up to five times. In addition, an MTT cell proliferation assay has been performed and suggests the non-cytotoxicity of DMPMS. Thus, the DMPMS-stamping bonding technique opens new perspectives for PDMS biochips where plasma treatment is not possible such as functionalised surfaces.

A fully-integrated frequency-divided tunable filter was newly designed and fabricated using an inductively coupled structure with lumped elements and MEMS fabrication technique. The inductively coupled structure allows for the size of the filter to be reduced, and electro-mechanically switched capacitors were used to obtain the tunability of frequency. When the proposed filter operated without using the switched capacitors, it exhibited insertion and return losses of 2.5 and 8 dB, respectively, in a single, wide passband with a range from 3.5 to 6 GHz. Otherwise, when the proposed filter operated with the use of the switched capacitors and a DC voltage bias of 30 V, a dual passband was formed at frequencies of less than 4.5 GHz and more than 5.5 GHz. Its size/volume was 3.3 × 1.7 × 0.535 (H) mm³.

Hexamethylene-1,3-bis(cetyldimethylammonium bromide) (G_16-6-16) protected low-toxicity ZnSe quantum dots (QDs) were successfully synthesised and used as fluorescence probe to detect proteins such as bovine serum albumin (BSA). This method is simple, fast, selective and sensitive. Surfactant G_16-6-16 can interact with proteins through hydrophobic effect, thus leading to the fluorescence quenching of G_16-6-16 protected ZnSe QDs nanometre material. The fluorescence intensity of G_16-6-16 protected ZnSe QDs was linearly proportional to BSA over a concentration range from 0 to 80 nM with a correlation coefficient of 0.993. The detection limit was 0.04 nM. This method was successfully applied to determine BSA in urine samples which shows the good application value of this nanometre material.

Thermal engineering parameters such as thermal conductivity (TC) can play an important role in developing medical nanofluids with improved stability and better drug release. In this reported work, an engineering perspective is strategised for the development of medical nanofluids containing functionalised single-wall carbon nanotubes and conjugated cisplatin. These nanofluids were developed by two biocompatible phospholipids. For the first time, the change in TC values of this medical nanofluid was investigated. The change in the drug release was examined before and after dialysis with change in pH and temperature, in vitro. It was found that an increase in temperature leads to higher TC and a decrease in pH provides better thermophysical conditions for the drug release. These findings strongly suggest that TC could be an important parameter in the development of medical nanofluids for cancer treatment.

The penetration of cell membrane using atomic force microscope (AFM) is studied. The penetration is monitored by AFM, and the penetration force is measured for three types of cells. The dissipated energy of the cell membrane before and after drug treatment is also calculated and analysed. Experimental results indicate that AFM is an efficient tool for measuring and monitoring the penetration of the cell membrane. Results also show that the penetration force differs significantly from each type of cells, indicating that the penetration force is a potential biomarker of cell membrane to distinguish different types of cells. Moreover, the dissipated energy of cell membrane is studied to be a biomarker to indicate the condition of the cell membrane. After the cell membrane is treated with dimethyl sulfoxide, the dissipated energy of cell membrane decreases.

Recent researches revealed that phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) plays an important role in the development of drug resistance, reducing the anti-tumour activity of cytotoxic drugs, such as docetaxel (DTX). The aim of this reported work has been to evaluate DTX and the PI3K/Akt inhibitor perifosine co-loaded Fol/R₇ (folate/R₇) nanoparticles (NPs) for enhancing anti-cancer activity. The NPs were evaluated by size, zeta potential and morphology. Then cell viability, cellular uptake and apoptosis were performed in MCF-7 and MCF-7/Adr cells. The PI3K/Akt inhibition effect was assessed by western blotting. Compared with other experimental groups, DTX and perifosine loaded Fol/R₇ NPs displayed the highest cytotoxicity, cell uptake and early apoptosis in MCF-7/Adr cells. Furthermore, the PI3K/Akt inhibition effect was enhanced by the Fol/R₇ NPs compared with the free drug group. The DTX and perifosine co-loaded Fol/R₇ NPs could be a potential, safe and efficient option for enhancing anti-cancer activity.

A silicon-on-insulator (SOI)-based microelectromechanical system solid propellant thruster array is presented. The micronozzle layer and microigniter layer of the array are formed on both surfaces of the SOI wafer, respectively. The layout design rules can properly distribute the heat produced by the microigniter below the solid propellant inside the chamber. Test results show that the highest temperature of the microigniter is located under the propellant. When one unit in the array is ignited by a DC voltage of 7.9 V, other units around it are not ignited. Moreover, the ignition resistors can work again, which means that the array can be used repeatedly when the solid propellant is refilled.

Short carbon fibre and silicon carbide (SiC) co-reinforced graphite matrix composites were prepared with natural flaky graphite as raw materials by low temperature hot pressing at 1900°C. The flexural strength in the direction perpendicular to the graphite layers reached 221 MPa for carbon fibre of 5 vol% and SiC of 30 vol%, which was an improvement of 275% compared with pure graphite materials. The composites improved the bend strength of the block obviously, while maintaining the thermal conductivity of 220 W/m K in the direction perpendicular to the hot pressing. The new process has the advantages of being a non-pitch binder process which avoids the high temperature graphitisation operation.

A graphene sheet (GS) synthetised from natural graphite powder was doped in titanium dioxide (TiO₂) through the sol–gel method to improve the photocatalytic activity and magnetic γ-Fe₂O₃/SiO₂ particles were added subsequently to improve recycling and reduce the waste of the catalyst. The morphology, microstructure, absorption spectrum and magnetic property of the γ-Fe₂O₃/SiO₂/GSs/TiO₂ composites were characterised via X-ray diffraction, transmission electron microscopy, diffuse-reflectance spectra and a vibrating sample magnetometer, respectively. The result revealed that (i) the nanocrystalline structure of γ-Fe₂O₃/SiO₂/GSs/TiO₂ composites is nearly unchanged compared with pure P25 nanoparticles; (ii) there was a redshift in the absorption edge of the photocatalyst composite; (iii) the photocatalyst composites displayed good superparamagnetism which was in favour of the reclamation of the catalyst; (iv) the adsorption and visible light photocatalytic activity of the composite is enhanced greatly on decomposition of methylene blue and (v) the photocatalysts maintained high photocatalytic activity after being reused several times.

A simple fabrication process for single-layer nanowire gratings (SLNGs) is proposed. On the basis of this process, an SLNG polariser with a 1.3 × 1.3 mm area of grating patterns and a 100 nm linewidth was successfully fabricated. First, the nanograting patterns were transferred from a metal master stamp to a soft IPS mould using the hot embossing process and the nanograting patterns on the IPS mould were transferred to the imprint resist layer by UV nanoimprint process subsequently; then, after a residual resist removal process, an aluminium layer was thermally evaporated on the substrate to form a bilayer nanowire grating structure; and finally, SLNGs were fabricated by an oxygen plasma ashing process. The inspection results show good consistency in the whole grating patterns area. The experimental result demonstrates that the proposed simple process can be adaptable to fabrications of high-density and large-area nanometal patterns.