A January 13, 2023 news item on phys.org announces research into genetically engineering bacteria so they produce melanin nanoparticles, i.e., biosynthetic melanin nanoparticles, Note: Links have been removed,
Photothermal therapy (PTT) has attracted considerable attention for the treatment of tumors because it is minimally invasive and has spatiotemporal selectivity.
Melanin is a kind of multifunctional pigment found widely in mammals, plants and microbes, with great prospects as a PTT agent for cancer treatment. Unfortunately, commercially available melanin is mainly obtained by chemical synthesis or extraction from sepia, which hinders its large-scale production and causes some potential safety hazards.
Recently, a research team led by Prof. Yan Fei from the Shenzhen Institute of Advanced Technology (SIAT) of the Chinese Academy of Sciences, together with Prof. Lin Jing from Shenzhen University and Prof. Xu Xiaohong from Guangdong Medical University, heterologously expressed a tyrosinase gene in Escherichia coli to synthesize melanin nanoparticles under mild and environmentally friendly conditions.
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Caption: Schematic illustration of biosynthetic melanin nanoparticles for photoacoustic imaging-guided photothermal therapy. Credit: SIAT [Shenzhen Institute of Advanced Technology]
The biosynthetic melanin nanoparticles exhibited excellent biocompatibility, good stability, and negligible toxicity. “They had strong absorption in the near-infrared region and higher photothermal conversion efficiency (48.9%) than chemically synthesized melanin-like polydopamine nanoparticles under an 808-nm laser irradiation,” said Prof. YAN.
The researchers further evaluated the photoacoustic imaging performance and antitumor efficacy of biosynthetic melanin nanoparticles. The results showed that the biosynthetic melanin nanoparticles had excellent photoacoustic imaging performance and could be used for photoacoustic imaging-guided photothermal therapy in vivo.
“Our study provided an alternative approach to synthesize PTT agents with broad application potential in the diagnosis and treatment of cancer,” said Prof. YAN.
They’re not calling this synthetic biology but I’ m pretty sure that altering a virus gene so the virus can spin gold (Rumpelstiltskin anyone?) qualifies. From an August 24, 2018 news item on ScienceDaily,
The race is on to find manufacturing techniques capable of arranging molecular and nanoscale objects with precision.
Engineers at the University of California, Riverside, have altered a virus to arrange gold atoms into spheroids measuring a few nanometers in diameter. The finding could make production of some electronic components cheaper, easier, and faster.
“Nature has been assembling complex, highly organized nanostructures for millennia with precision and specificity far superior to the most advanced technological approaches,” said Elaine Haberer, a professor of electrical and computer engineering in UCR’s Marlan and Rosemary Bourns College of Engineering and senior author of the paper describing the breakthrough. “By understanding and harnessing these capabilities, this extraordinary nanoscale precision can be used to tailor and build highly advanced materials with previously unattainable performance.”
Viruses exist in a multitude of shapes and contain a wide range of receptors that bind to molecules. Genetically modifying the receptors to bind to ions of metals used in electronics causes these ions to “stick” to the virus, creating an object of the same size and shape. This procedure has been used to produce nanostructures used in battery electrodes, supercapacitors, sensors, biomedical tools, photocatalytic materials, and photovoltaics.
The virus’ natural shape has limited the range of possible metal shapes. Most viruses can change volume under different scenarios, but resist the dramatic alterations to their basic architecture that would permit other forms.
The M13 bacteriophage, however, is more flexible. Bacteriophages are a type of virus that infects bacteria, in this case, gram-negative bacteria, such as Escherichia coli, which is ubiquitous in the digestive tracts of humans and animals. M13 bacteriophages genetically modified to bind with gold are usually used to form long, golden nanowires.
Studies of the infection process of the M13 bacteriophage have shown the virus can be converted to a spheroid upon interaction with water and chloroform. Yet, until now, the M13 spheroid has been completely unexplored as a nanomaterial template.
Haberer’s group added a gold ion solution to M13 spheroids, creating gold nanobeads that are spiky and hollow.
“The novelty of our work lies in the optimization and demonstration of a viral template, which overcomes the geometric constraints associated with most other viruses,” Haberer said. “We used a simple conversion process to make the M13 virus synthesize inorganic spherical nanoshells tens of nanometers in diameter, as well as nanowires nearly 1 micron in length.”
The researchers are using the gold nanobeads to remove pollutants from wastewater through enhanced photocatalytic behavior.
The work enhances the utility of the M13 bacteriophage as a scaffold for nanomaterial synthesis. The researchers believe the M13 bacteriophage template transformation scheme described in the paper can be extended to related bacteriophages.
Happily, I’m getting more nanotechnology (for the most part) information from Japan. Given Japan’s prominence in this field of endeavour I’ve long felt FrogHeart has not adequately represented Japanese contributions. Now that I’m receiving English language translations, I hope to better address the situation.
This morning (March 26, 2015), there were two news releases from Kawasaki INnovation Gateway at SKYFRONT (KING SKYFRONT), Coastal Area International Strategy Office, Kawasaki City, Japan in my mailbox. Before getting on to the news releases, here’s a little about the city of Kawasaki and about its innovation gateway. From the Kawasaki, Kanagawa entry in Wikipedia (Note: Links have been removed),
Kawasaki (川崎市 Kawasaki-shi?) is a city in Kanagawa Prefecture, Japan, located between Tokyo and Yokohama. It is the 9th most populated city in Japan and one of the main cities forming the Greater Tokyo Area and Keihin Industrial Area.
Kawasaki occupies a belt of land stretching about 30 kilometres (19 mi) along the south bank of the Tama River, which divides it from Tokyo. The eastern end of the belt, centered on JR Kawasaki Station, is flat and largely consists of industrial zones and densely built working-class housing, the Western end mountainous and more suburban. The coastline of Tokyo Bay is occupied by vast heavy industrial complexes built on reclaimed land.
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There is a 2014 video about Kawasaki’s innovation gateway, which despite its 14 mins. 39 secs. running time I am embedding here. (Caution: They highlight their animal testing facility at some length.)
Now on to the two news releases. The first concerns research on gold nanoparticles that was published in 2014. From a March 26, 2015 Kawasaki INnovation Gateway news release,
Gold nanoparticles size up to cancer treatment
Incorporating gold nanoparticles helps optimise treatment carrier size and stability to improve delivery of cancer treatment to cells.
Treatments that attack cancer cells through the targeted silencing of cancer genes could be developed using small interfering RNA molecules (siRNA). However delivering the siRNA into the cells intact is a challenge as it is readily degraded by enzymes in the blood and small enough to be eliminated from the blood stream by kidney filtration. Now Kazunori Kataoka at the University of Tokyo and colleagues at Tokyo Institute of Technology have designed a protective treatment delivery vehicle with optimum stability and size for delivering siRNA to cells.
The researchers formed a polymer complex with a single siRNA molecule. The siRNA-loaded complex was then bonded to a 20 nm gold nanoparticle, which thanks to advances in synthesis techniques can be produced with a reliably low size distribution. The resulting nanoarchitecture had the optimum overall size – small enough to infiltrate cells while large enough to accumulate.
In an assay containing heparin – a biological anti-coagulant with a high negative charge density – the complex was found to release the siRNA due to electrostatic interactions. However when the gold nanoparticle was incorporated the complex remained stable. Instead, release of the siRNA from the complex with the gold nanoparticle could be triggered once inside the cell by the presence of glutathione, which is present in high concentrations in intracellular fluid. The glutathione bonded with the gold nanoparticles and the complex, detaching them from each other and leaving the siRNA prone to release.
The researchers further tested their carrier in a subcutaneous tumour model. The authors concluded that the complex bonded to the gold nanoparticle “enabled the efficient tumor accumulation of siRNA and significant in vivo gene silencing effect in the tumor, demonstrating the potential for siRNA-based cancer therapies.”
The news release provides links to the March 2015 newsletter which highlights this research and to the specific article and video,
The second March 26, 2015 Kawasaki INnovation Gateway news release concerns a DNA chip and food-borne pathogens,
Rapid and efficient DNA chip technology for testing 14 major types of food borne pathogens
Conventional methods for testing food-borne pathogens is based on the cultivation of pathogens, a process that is complicated and time consuming. So there is demand for alternative methods to test for food-borne pathogens that are simpler, quick and applicable to a wide range of potential applications.
Now Toshiba Ltd and Kawasaki City Institute for Public Health have collaborated in the development of a rapid and efficient automatic abbreviated DNA detection technology that can test for 14 major types of food borne pathogens. The so called ‘DNA chip card’ employs electrochemical DNA chips and overcomes the complicated procedures associated with genetic testing of conventional methods. The ‘DNA chip card’ is expected to find applications in hygiene management in food manufacture, pharmaceuticals, and cosmetics.
Details
The so-called automatic abbreviated DNA detection technology ‘DNA chip card’ was developed by Toshiba Ltd and in a collaboration with Kawasaki City Institute for Public Health, used to simultaneously detect 14 different types of food-borne pathogens in less than 90 minutes. The detection sensitivity depends on the target pathogen and has a range of 1E+01~05 cfu/mL.
Notably, such tests would usually take 4-5 days using conventional methods based on pathogen cultivation. Furthermore, in contrast to conventional DNA protocols that require high levels of skill and expertise, the ‘DNA chip card’ only requires the operator to inject nucleic acid, thereby making the procedure easier to use and without specialized operating skills.
Examples of pathogens associated with food poisoning that were tested with the “DNA chip card”
Enterohemorrhagic Escherichia coli
Salmonella
Campylobacter
Vibrio parahaemolyticus
Shigella
Staphylococcus aureus
Enterotoxigenic Escherichia coli
Enteroaggregative Escherichia coli
Enteropathogenic Escherichia coli
Clostridium perfringens
Bacillus cereus
Yersinia
Listeria
Vibrio cholerae
I think 14 is the highest number of tests I’ve seen for one of these chips. This chip is quite an achievement.
One final bit from the news release about the DNA chip provides a brief description of the gateway and something they call King SkyFront,
About KING SKYFRONT
The Kawasaki INnovation Gateway (KING) SKYFRONT is the flagship science and technology innovation hub of Kawasaki City. KING SKYFRONT is a 40 hectare area located in the Tonomachi area of the Keihin Industrial Region that spans Tokyo and Kanagawa Prefecture and Tokyo International Airport (also often referred to as Haneda Airport).
KING SKYFRONT was launched in 2013 as a base for scholars, industrialists and government administrators to work together to devise real life solutions to global issues in the life sciences and environment.
I find this emphasis on the city interesting. It seems that cities are becoming increasingly important and active where science research and development are concerned. Europe seems to have adopted a biannual event wherein a city is declared a European City of Science in conjunction with the EuroScience Open Forum (ESOF) conferences. The first such city was Dublin in 2012 (I believe the Irish came up with the concept themselves) and was later adopted by Copenhagen for 2014. The latest city to embrace the banner will be Manchester in 2016.
I had never, ever expected to mention mixed martial arts (MMA) here but that’s one of the delightful aspects of writing about nanotechnology; you never know where it will take you. A March 9, 2015 news item on Azonano describes the wound situation for athletes and a new product,
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As an MMA Champion athlete, Rich Franklin knows all too well about germs and how easily they spread. During training he dealt with them on a regular basis, but it wasn’t until the first time he had staph, did he realize these infections could cost him a victory. Now, working in a global setting, Franklin trains in locations around the world which leaves him exposed to a plethora of bacteria and fungi. So he teamed up with American Biotech Labs (ABL) to develop Armor Gel, nano silver-based, wound dressing gel that can stay active on the skin for up to seventy-two hours (3 days). Using patented nano silver technology, Armor Gel has been scientifically tested to reduce the levels of bacteria and other pathogens, while forming a protective barrier “armor” over the wound. By shielding the body from external bacterial, the body’s natural healing process can be expedited. Its use is recommended by doctors, trainers, coaches, and athletes alike.
A March 6, 2015 ABL news release on BusinessWire, which originated the news item, provides a little more detail about Armor Gel,
Engineered for today’s modern athletes, Armor Gel is safe, nontoxic and provides a personal first line of defense. Already proven to reduce the levels of MRSA, VRE, pseudomonas aeruginosa, E. coli, A. niger and Candida albicans, Armor Gel is formulated using a unique and patented 24 SilverSol Technology®.
American Biotech Labs (ABL) was started in 2002 as a nano silver biotech company with the goal of creating a more stable and powerful silver technology for consumer products. …
I am providing a link to the product website (neither the link nor this post are endorsements), you can find out more about Armor Gel here.
Armor Gel was announced previously in a Sept. 16, 2014 ABL news release on PR Newswire, At the time no mention was made of Rich Franklin, their MMA athlete,
American Biotech Labs, LLC, is pleased to announce the availability of three new silver hydrogel wound-dressing products. The new products will allow American Biotech Labs (ABL) to market in the wound-care market focusing on ultimate sports and fitness, spa and health, and animal markets.
The new over-the-counter (OTC) products will have wound-dressing claims for minor cuts, lacerations, abrasions, 1st and 2nd degree burns, and skin irritations. The products also have pathogen-inhibiting barrier claims against pathogens, such as Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, MRSA and VRE, as well as fungi, such as Candida albicans and Aspergillus niger. These new gels can provide a barrier that will help protect wounds for 24 to 72 hours.
The new products will be found under the names of Armor Gel™ (for the ultimate sports and fitness market), ASAP OTC™ (for the spa and health markets), and ASAP Pet Shield® (for the animal market).
Along with the release of these new products, ABL has formed a strategic alliance with Stuart Evey, founder and former chairman of ESPN, and Gary Bernstein, marketing executive and professional photographer and film maker. ABL will utilize these talented individuals to help introduce these revolutionary new products to high-profile organizations in sports, pet stores, fashion and beauty, medical, and direct-marketing areas, etc.
Said Keith Moeller, ABL Director, “We are very grateful to the numerous top scientists, labs and universities that have helped move this amazing, patented, silver technology forward. We believe that these products have the ability to impact the future of wound management worldwide.”
Note: Any statements released by American Biotech Labs, LLC that are forward looking are made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Editors and investors are cautioned that forward looking statements invoke risk and uncertainties that may affect the company’s business prospects and performance.
