Multiplex antibiotic susceptibility testing of urinary tract infections using an electrochemical lab-on-a-chip.

Urinary tract infections (UTIs) represent the most prevalent type of outpatient infection, with significant adverse health and economic burdens. Current culture-based antibiotic susceptibility testing can take up to 72 h resulting in ineffective prescription of broad-spectrum antibiotics, poor clinical outcomes and development of further antibiotic resistance. We report an electrochemical lab-on-a-chip (LOC) for testing samples against seven clinically-relevant antibiotics.

Genetic identification of three CITES-listed sharks using a paper-based Lab-on-a-Chip (LOC).

Threatened shark species are caught in large numbers by artisanal and commercial fisheries and traded globally. Monitoring both which shark species are caught and sold in fisheries, and the export of CITES-restricted products, are essential in reducing illegal fishing. Current methods for species identification rely on visual examination by experts or DNA barcoding techniques requiring specialist laboratory facilities and trained personnel.

Rapid antibiotic susceptibility testing using resazurin bulk modified screen-printed electrochemical sensing platforms.

Urinary tract infections (UTIs) are one of the most common types of bacterial infection. UTIs can be associated with multidrug resistant bacteria and current methods of determining an effective antibiotic for UTIs can take up to 48 hours, which increases the chances of a negative prognosis for the patient. In this paper we report for the first time, the fabrication of resazurin bulk modified screen-printed macroelectrodes (R-SPEs) demonstrating them to be effective platforms for the electrochemical detection of antibiotic susceptibility in complicated UTIs.

Non-thermal plasma-based inactivation of bacteria in water using a microfluidic reactor.

Failure of conventional water treatment systems may lead to the contamination of water sources, which can cause outbreaks of waterborne healthcare associated infections. Advanced oxidation processing by non-thermal plasma has the potential to treat water without the addition of chemicals. Antibiotic resistant Pseudomonas aeruginosa and Escherichia coli were chosen to investigate the use of non-thermal plasma generated in a microfluidic reactor to disinfect bacteria contaminated water.

On-site genetic analysis for species identification using lab-on-a-chip.

This paper presents a microfluidic device capable of performing genetic analysis on dung samples to identify White Rhinoceros (). The development of a microfluidic device, which can be used in the field, offers a portable and cost-effective solution for DNA analysis and species identification to aid conservation efforts. Optimization of the DNA extraction processes produced equivalent yields compared to conventional kit-based methods within just 5 minutes.

Ten golden rules for reforestation to optimize carbon sequestration, biodiversity recovery and livelihood benefits.

Urgent solutions to global climate change are needed. Ambitious tree-planting initiatives, many already underway, aim to sequester enormous quantities of carbon to partly compensate for anthropogenic CO emissions, which are a major cause of rising global temperatures. However, tree planting that is poorly planned and executed could actually increase CO emissions and have long-term, deleterious impacts on biodiversity, landscapes and livelihoods.

Are concentrations of pollutants in sharks, rays and skates (Elasmobranchii) a cause for concern? A systematic review.

This review represents a comprehensive analysis on pollutants in elasmobranchs including meta-analysis on the most studied pollutants: mercury, cadmium, PCBs and DDTs, in muscle and liver tissue. Elasmobranchs are particularly vulnerable to pollutant exposure which may pose a risk to the organism as well as humans that consume elasmobranch products. The highest concentrations of pollutants were found in sharks occupying top trophic levels (Carcharhiniformes and Lamniformes).

Investigating cat predation as the cause of bat wing tears using forensic DNA analysis.

Cat predation upon bat species has been reported to have significant effects on bat populations in both rural and urban areas. The majority of research in this area has focussed on observational data from bat rehabilitators documenting injuries, and cat owners, when domestic cats present prey. However, this has the potential to underestimate the number of bats killed or injured by cats.

Characterizing wing tears in common pipistrelles (): investigating tear distribution, wing strength, and possible causes.

Bats have large, thin wings that are particularly susceptible to tearing. Anatomical specializations, such as fiber reinforcement, strengthen the wing and increase its resistance to puncture, and an extensive vasculature system across the wing also promotes healing. We investigated whether tear positioning is associated with anatomy in common pipistrelles ().

Application of Microfluidic Methodology for the Analysis of DNA.

Over the past 20 years, many of the developments and potential applications of microfluidic methodology have incorporated nucleic acid processes which have, in their own right, undergone a number of innovative changes [...

The preparation of microfluidic architecture with monolithic materials using a dual porous silica structure.

A microfluidic device (MD) has been developed which features a porous silica (PS) monolithic disk synthesized from tetramethyl orthosilicate, incorporated into the device post-fabrication and sealed in place with a second PS monolithic layer, synthesized from potassium silicate. This dual porous silica (DPS) structure provides a pathway for sample introduction to the MD and offers an ideal platform for solid phase extraction (SPE) methodologies which can be rapidly and efficiently integrated into a chip-based format. All silica disk manufacture and functionalization was carried out in batch to provide a readily scalable method of production.

Combining Electro-Osmotic Flow and FTA Paper for DNA Analysis on Microfluidic Devices.

FTA paper can be used to protect a variety of biological samples prior to analysis, facilitating ease-of-transport to laboratories or long-term archive storage. The use of FTA paper as a solid phase eradicates the need to elute the nucleic acids from the matrix prior to DNA amplification, enabling both DNA purification and polymerase chain reaction (PCR)-based DNA amplification to be performed in a single chamber on the microfluidic device. A disc of FTA paper, containing a biological sample, was placed within the microfluidic device on top of wax-encapsulated DNA amplification reagents.

Sex identification of ancient DNA samples using a microfluidic device.

Ancient DNA is the name given to the degraded, fragmented, and chemically damaged biomolecules that can be recovered from archaeological remains of plants, animals, and humans. Where ancient human DNA has survived at archaeological sites, it can give valuable information and is especially useful for its potential to identify kinship, population affinities, pathogens, and biological sex. Here, we describe the operation of a microfluidic device for the sex identification of ancient DNA samples using an efficient sample handling process.

Integrated RNA extraction and RT-PCR for semi-quantitative gene expression studies on a microfluidic device.

This paper describes the development of a microfluidic methodology, using RNA extraction and reverse transcription PCR, for investigating expression levels of cytochrome P450 genes. Cytochrome P450 enzymes are involved in the metabolism of xenobiotics, including many commonly prescribed drugs, therefore information on their expression is useful in both pharmaceutical and clinical settings. RNA extraction, from rat liver tissue or primary rat hepatocytes, was performed using a silica-based solid-phase extraction technique.

Development of a real-world direct interface for integrated DNA extraction and amplification in a microfluidic device.

Integrated DNA extraction and amplification have been carried out in a microfluidic device using electro-osmotic pumping (EOP) for fluidic control. All the necessary reagents for performing both DNA extraction and polymerase chain reaction (PCR) amplification were pre-loaded into the microfluidic device following encapsulation in agarose gel. Buccal cells were collected using OmniSwabs [Whatman™, UK] and manually added to a chaotropic binding/lysis solution pre-loaded into the microfluidic device.

Rapid PCR amplification using a microfluidic device with integrated microwave heating and air impingement cooling.

A microwave heating system is described for performing polymerase chain reaction (PCR) in a microfluidic device. The heating system, in combination with air impingement cooling, provided rapid thermal cycling with heating and cooling rates of up to 65 degrees C s(-1) and minimal over- or under-shoot (+/-0.1 degrees C) when reaching target temperatures.

Simple practical approach for sample loading prior to DNA extraction using a silica monolith in a microfluidic device.

A novel DNA loading methodology is presented for performing DNA extraction on a microfluidic system. DNA in a chaotropic salt solution was manually loaded onto a silica monolith orthogonal to the subsequent flow of wash and elution solutions. DNA was successfully extracted from buccal swabs using electro-osmotic pumping (EOP) coupled with in situ reagents contained within a 1.

The use of carrier RNA to enhance DNA extraction from microfluidic-based silica monoliths.

DNA extraction was carried out on silica-based monoliths within a microfluidic device. Solid-phase DNA extraction methodology was applied in which the DNA binds to silica in the presence of a chaotropic salt, such as guanidine hydrochloride, and is eluted in a low ionic strength solution, such as water. The addition of poly-A carrier RNA to the chaotropic salt solution resulted in a marked increase in the effective amount of DNA that could be recovered (25ng) compared to the absence of RNA (5ng) using the silica-based monolith.

Development of a bi-functional silica monolith for electro-osmotic pumping and DNA clean-up/extraction using gel-supported reagents in a microfluidic device.

A silica monolith used to support both electro-osmotic pumping (EOP) and the extraction/elution of DNA coupled with gel-supported reagents is described. The benefits of the combined EOP extraction/elution system were illustrated by combining DNA extraction and gene amplification using the polymerase chain reaction (PCR) process. All the reagents necessary for both processes were supported within pre-loaded gels that allow the reagents to be stored at 4 degrees C for up to four weeks in the microfluidic device.

Comparison of the effects of sterilisation techniques on subsequent DNA profiling.

It is important that contamination from extraneous DNA should be minimised on items used at crime scenes and when dealing with exhibits within the laboratory. Four sterilisation techniques (UV, gamma and beta radiation and ethylene oxide treatment) were examined for their potential to degrade contaminating DNA to such an extent that subsequent DNA profiling was impossible. This work indicated that the most successful technique to reduce DNA contamination was ethylene oxide treatment.