Tag Archives: bacteria

How To Kill Deadly Hospital Bacteria

Scientists at Aston University (UK) have discovered a technique similar to medieval stained glass-making that can completely eradicate the deadliest hospital infections within hours.

Using a so-called bioactive phosphate glass containing small amounts of the metallic element cobalt, the researchers were able to achieve a “complete kill” of the deadly bacterial infections E.coli and Candida albicans (a fungal infection associated with surgery), as well as a near-complete kill of Staphylococcus aureus (the drug-resistant form of which is MRSA).


Lead researcher, Dr Richard Martin of Aston University in Birmingham, said the findings had significant implications, offering the possibility of cheap, antimicrobial implants and coatings to combat the most common sources of infections associated with medical care. Avoiding the need for antibiotics, it is also thought the bioactive glass could be effective against drug-resistantsuperbugs’, helping to tackle the growing problem of antimicrobial resistance (AMR).

According to the European Centre for Disease Prevention and Control (ECDC), over four million people in Europe get a healthcare-associated infection (HAI) every year, and around 37,000 die as a direct result of the infection. In its most recent survey of hospital patients, Public Health England found that 6.4% had a healthcare-associated infection.

In the study, published in the journal ACS Biomaterials, the researchers used a centuries-old technique to make glass laced with trace amounts of cobalt in a furnace heated to over 1,000°C, before rapid cooling to prevent crystallisation. These were then ground down into a fine powder and put into contact with bacteria in petri dishes. The glasses contained varying concentrations of cobalt, providing a controlled release of antimicrobial ions as they dissolved. At the highest concentration, the glass completely eradicated E.coli within just six hours, with a “complete kill” also observed for C.albicans within 24 hours. S.aureus levels were reduced by 99% after 24 hours.

Source: https://www2.aston.ac.uk/

Self-Sterilizing Microneedles

Vaccinations are the world’s frontline defence against infectious diseases yet despite decades of interventions, unsafe injection practices continue to expose billions of people to serious infection and disease.

Now, new technology from the University of South Australia is revolutionising safe vaccination practices through antibacterial, silver-loaded dissolvable microneedle patches, which not only sterilise the injection site to inhibit the growth of bacteria, but also physically dissolve after administration.

These first generation microneedles have the potential to transform the safe administration of transdermal vaccinations and drug delivery”, explains Lead researcher, Professor Krasimir Vasilev .

Injections are one of the most common health care procedures used for vaccinations and curative care around the world,” Prof Vasilev adds. “But up to 40 per cent of injections are given with improperly sterilised syringes and needles, placing millions of people at risk of contracting a range of illnesses or diseases. “Our silver-loaded microneedles have inherently potent antibacterial properties which inhibit the growth of pathogenic bacteria and reduce the chance of infection.”

The UniSA study tested the antibacterial efficacy of silver-loaded microneedles against bacteria associated with common skin infections – Golden staph, staphylococcus epidermis, escherichia coli and pseudomonas aeruginosa – and found that the silver-loaded microneedle patches created a 24-hour bacteria-free zone around the patch administration site, a feature unique to the new technology.

The silver-loaded microneedles comprise an array of 15 x 15 needles each 700 micron in length, which pierce only the top layer of the skin without reaching the underlying nerves, making them 100 per cent painless.

The microneedles are made from a safe, biocompatible and highly water-soluble polymer that completely dissolve within one minute of application, leaving behind no sharp waste.

Source: http://www.unisa.edu.au/

How To ConVert Waste Heat Into Electricity

Thermoelectric materials, capable of transforming heat into electricity, are very promising when converting residual heat into electrical energy, since they allow us to utilize hardly usable or almost lost thermal energy in an efficient way. Researchers at the Institute of Materials Science of Barcelona (ICMAB-CSIC) have created a new thermoelectric material: a paper capable of converting waste heat into electricity. These devices could be used to generate electricity from residual heat to feed sensors in the field of the Internet of Things, Agriculture 4.0 or Industry 4.0.

This device is composed of cellulose, produced in situ in the laboratory by bacteria, with small amounts of a conductor nanomaterial, carbon nanotubes, using a sustainable and environmentally friendly strategy” explains Mariano Campoy-Quiles, researcher at the ICMAB.

“In the near future, they could be used as wearable devices, in medical or sports applications, for example. And if the efficiency of the device was even more optimized, this material could lead to intelligent thermal insulators or to hybrid photovoltaic-thermoelectric power generation systems” predicts Campoy-Quiles. In addition “due to the high flexibility of the cellulose and to the scalability of the process, these devices could be used in applications where the residual heat source has unusual forms or extensive areas, as they could be completely covered with this material” indicates Anna Roig, researcher at the ICMAB.

Since bacterial cellulose can be home made, perhaps we are facing the first step towards a new energy paradigm, where users will be able to make their own electric generators. We are still far away, but this study is a beginning. We have to start somewhere. “Instead of making a material for energy, we cultivate it” explains Mariano Campoy-Quiles, a researcher of this study. “Bacteria, dispersed in an aqueous culture medium containing sugars and carbon nanotubes, produce the nanocellulose fibers that will end up forming the device, in which the carbon nanotubes are embedded” continues Campoy-Quiles.”We obtain a mechanically resistant, flexible and deformable material, thanks to the cellulose fibers, and with a high electrical conductivity, thanks to the carbon nanotubes,” adds Anna Laromaine, researcher at the ICMAB. “The intention is to approach the concept of circular economy, using sustainable materials that are not toxic for the environment, which are used in small amounts, and which can be recycled and reused,“says Roig.

The study has been published in the Energy & Environmental Science journal.

Source: http://icmab.es/

Nanorobots Deliver Drugs Directly To Diseased Tissue

Scientists at EPFL and ETH Zurich in Switzerland have developed tiny elastic robots that can change shape depending on their surroundings. Modeled after bacteria and fully biocompatible, these robots optimize their movements so as to get to hard-to-reach areas of the human body. They stand to revolutionize targeted drug delivery.

One day we may be able to ingest tiny robots that deliver drugs directly to diseased tissue, thanks to research being carried out at EPFL and ETH Zurich.


The robots are modeled after bacteria and fully biocompatible© 2019 EPFL/ ETHZ

The group of scientists – led by Selman Sakar at EPFL and Bradley Nelson at ETH Zurich – drew inspiration from bacteria to design smart, biocompatible microrobots that are highly flexible. Because these devices are able to swim through fluids and modify their shape when needed, they can pass through narrow blood vessels and intricate systems without compromising on speed or maneuverability. They are made of hydrogel nanocomposites that contain magnetic nanoparticles allowing them to be controlled via an electromagnetic field.

In an article appearing in Science Advances, the scientists describe the method they have developed for “programming the robot’s shape so that it can easily travel through fluids that are dense, viscous or moving at rapid speeds. When we think of robots, we generally think of bulky machines equipped with complex systems of electronics, sensors, batteries and actuators. But on a microscopic scale, robots are entirely different.

Fabricating miniaturized robots presents a host of challenges, which the scientists addressed using an origami-based folding method. Their novel locomotion strategy employs embodied intelligence, which is an alternative to the classical computation paradigm that is performed by embedded electronic systems.Our robots have a special composition and structure that allow them to adapt to the characteristics of the fluid they are moving through. For instance, if they encounter a change in viscosity or osmotic concentration, they modify their shape to maintain their speed and maneuverability without losing control of the direction of motion,” says Sakar.

These deformations can be “programmed” in advance so as to maximize performance without the use of cumbersome sensors or actuators. The robots can be either controlled using an electromagnetic field or left to navigate on their own through cavities by utilizing fluid flow. Either way, they will automatically morph into the most efficient shape.

Source: https://actu.epfl.ch/

Genetic Codes Mapping Of 3,000 Dangerous Bacteria

Scientists seeking new ways to fight drug-resistant superbugs have mapped the genomes of more than 3,000 bacteria, including samples of a bug taken from Alexander Fleming’s nose and a dysentery-causing strain from a World War One soldier. The DNA of deadly strains of plague, dysentery and cholera were also decoded in what the researchers said was an effort to better understand some of the world’s most dangerous diseases and develop new ways to fight them. The samples from Fleming – the British scientist credited with discovering the first antibiotic, penicillin, in 1928 – were among more than 5,500 bugs at Britain’s National Collection of Type Cultures (NCTC) one of the world’s largest collections of clinically relevant bacteria. The first bacteria to be deposited in the NCTC was a strain of dysentery-causing Shigella flexneri that was isolated in 1915 from a soldier in the trenches of World War One.

“Knowing very accurately what bacteria looked like before and during the introduction of antibiotics and vaccines, and comparing them to current strains, … shows us how they have responded to these treatments,” said Julian Parkhill of Britain’s Wellcome Sanger Institute who co-led the research. “This in turn helps us develop new antibiotics and vaccines.”

Specialists estimate that around 70 percent of bacteria are already resistant to at least one antibiotic that is commonly used to treat them. This has made the evolution of “superbugs” that can evade one or multiple drugs one of the biggest threats facing medicine today. Among the most serious risks are tuberculosis – which infects more than 10.4 million people a year and killed 1.7 million in 2016 alone – and gonorrhea, a sexually transmitted disease that infects 78 million people a year and which the World Health Organization says is becoming almost untreatable.

Source: https://www.reuters.com/

Nanorobots Clear Bacteria From Blood

Engineers at the University of California San Diego have developed tiny ultrasound-powered robots that can swim through blood, removing harmful bacteria along with the toxins they produce. These proof-of-concept nanorobots could one day offer a safe and efficient way to detoxify and decontaminate biological fluids.

Researchers built the nanorobots by coating gold nanowires with a hybrid of platelet and red blood cell membranes. This hybrid cell membrane coating allows the nanorobots to perform the tasks of two different cells at once—platelets, which bind pathogens like MRSA bacteria (an antibiotic-resistant strain of Staphylococcus aureus), and red blood cells, which absorb and neutralize the toxins produced by these bacteria. The gold body of the nanorobots responds to ultrasound, which gives them the ability to swim around rapidly without chemical fuel. This mobility helps the nanorobots efficiently mix with their targets (bacteria and toxins) in blood and speed up detoxification.

The work, published May 30 in Science Robotics, combines technologies pioneered by Joseph Wang and Liangfang Zhang, professors in the Department of NanoEngineering at the UC San Diego Jacobs School of Engineering. Wang’s team developed the ultrasound-powered nanorobots, and Zhang’s team invented the technology to coat nanoparticles in natural cell membranes.

SEM image of a MRSA bacterium attached to a hybrid cell membrane coated nanorobot

By integrating natural cell coatings onto synthetic nanomachines, we can impart new capabilities on tiny robots such as removal of pathogens and toxins from the body and from other matrices,” said Wang. “This is a proof-of-concept platform for diverse therapeutic and biodetoxification applications.”

The idea is to create multifunctional nanorobots that can perform as many different tasks at once,” adds co-first author Berta Esteban-Fernández de Ávila, a postdoctoral scholar in Wang’s research group at UC San Diego. “Combining platelet and red blood cell membranes into each nanorobot coating is synergistic—platelets target bacteria, while red blood cells target and neutralize the toxins those bacteria produce.

Source: http://jacobsschool.ucsd.edu/