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Microdroplet reactors mimic living systems to study non-equilibrium reactions like those in living organisms

“Living systems are achieved by complex chemical reaction dynamics far from equilibrium, such as gene expression networks, signalling networks, metabolic circuits and neural networks,” explain Masahiro Takinoue at Tokyo Institute of Technology and his colleagues. The researchers now demonstrate that their microdroplet system can offer the control over chemical fluxes needed to keep this kind of reaction far from equilibrium.
Accordng to the original paper entitled ”Pulse-density modulation control of chemical oscillation far from equilibrium in a droplet open-reactor system”, published on Nature Communications  (DOI: 10.1038/ncomms10212), Takinoue and his colleagues used a microfluidic system containing a droplet of water in oil with electrodes either side as the chemical reaction site. They then passed a train of water-in-oil droplets past the reactor droplet. As each droplet passed the reactor droplet, applying an a.c. voltage across the electrodes led to fusion, allowing chemical exchange. The shear force of the droplet train then caused fission, leaving the reactor droplet self-contained until voltage-induced fusion with the following droplet.
The research team mathematically modelled how by switching the a.c. voltage on and off they could control the fusion/fission timing, and hence the chemical flux and reaction dynamics. As a model system, they then produced a microdroplet system of bromite (BrO3-), sulphite (SO32-) and ferrocyanide (Fe(CN)64-). The pH in the droplet oscillates as hydrogen cations are produced and consumed through autocatalytic reactions. Using pH-sensitive fluorescent molecules, the researchers could monitor these reaction dynamics and incorporate feedback.
“Complicated microfluidic components, such as valves and mixers, are unnecessary,” point out the researchers, as the a.c. voltage pulse-modulated reactor provides chemical flux control. In addition the fast fusion response to the applied electric field allows a range of waveforms of the droplet train density to be studied, including sinusoidal, square and saw tooth. As a result it could provide a powerful tool for studying synthetic biology to understand life, as well as bio-inspired self-controlling and dynamic systems.

Potential applications
Among other applications, the system may provide a complex reaction system for research in synthetic biology such as artificial DNA circuits, and gene circuits, metabolic systems and microchemostat-like reactors. Researchers also highlight that the a.c. voltage pulse-density modulation used to control the microdroplet reactor system is compatible with control theory for dynamical systems in general. In addition it may have applications in computational intelligence, which is a set of methods inspired by nature that are designed to tackle real-world problems intractable to traditional mathematical approaches. It is also an ideal platform for developing software-wetware technologies.

Source: Tokyo Institute of Technology
Press release


Scientists synthesize nanoparticles that can deliver tumor suppressors to damaged livers

UT Southwestern Medical Center chemists have successfully used synthetic nanoparticles to deliver tumor-suppressing therapies to diseased livers with cancer, an important hurdle scientists have been struggling to conquer.
Late-stage liver cancer is a major challenge for therapeutic intervention. Drugs that show promise in healthy functioning livers can cause devastating toxicity in cirrhotic livers with cancer, the researchers explained. 
UT Southwestern scientists crafted synthetic “dendrimer” nanoparticles that are able to provide the tumor-suppressing effect without further damaging the liver or neighboring tissue. The findings appear in the journal, Proceedings of the National Academy of Sciences.
“We have synthesized highly effective dendrimer carriers that can deliver drugs to tumor cells without adverse side effects, even when the cancerous liver is consumed by the disease,” said Dr. Daniel Siegwart, Assistant Professor of Biochemistry and with the Harold C. Simmons Comprehensive Cancer Center. “We found that efficacy required a combination of a small RNA drug that can suppress cancer growth and the carrier, thereby solving a critical issue in treating aggressive liver cancer and providing a guide for future drug development.”
The recent failure of five phase III human clinical trials of small-molecule drugs to treat hepatocellular carcinoma – the most common form of liver cancer – prompted the authors to develop non-toxic carriers and explore “miRNA” therapies as a promising alternative. MicroRNAs (miRNAs) are short nucleic acids that can function as natural tumor suppressors, but require delivery strategies to transport these large, anionic drugs into cells. To date, no existing carrier has been able to provide effective delivery to late-stage liver cancer without amplified toxicity, which negates the desired effect.
To address this problem, UTSW scientists chemically synthesized more than 1,500 different types of nanoparticles, which allowed discovery of lead compounds that could function in the heavily compromised cancerous liver. Synthetic, man-made nanoscale compounds called dendrimers provided an opportunity to screen different combinations of chemical groups, physical properties, and molecular size, Dr. Siegwart said. This approach led to the identification of dendrimers to deliver miRNA to late-stage liver tumors with low liver toxicity.
The study, conducted in genetic mouse models with a highly aggressive form of liver cancer, demonstrated that the miRNA nanoparticles inhibited tumor growth and dramatically extended survival.



The Rocket Synergy Evaporator from Genevac is proven to provide fast, unattended operation that significantly improves environmental laboratory productivity. Developed as a result of users’ demands for an evaporator that could quickly process large-volume environmental samples in parallel without supervision, the Rocket Synergy Evaporator can concentrate or dry 18 ASE tubes or up to 6 large-volume 450 ml flasks. This enables the user to focus on other tasks, confident that the Rocket Synergy Evaporator will achieve reproducible evaporation with excellent recovery rates. In addition using Genevac’s proprietary SampleGenie™ technology in conjunction with the Rocket Synergy evaporator enables samples to be concentrated directly into an autosampler or storage vial, eliminating the need for manual sample transfer. To automate transfers from ASE® vials the Genevac Flip-Flop™ system can be used. This elimination of manual transfer steps and the automation of the evaporation / concentration process deliver significantly improved environmental laboratory workflow, better reproducibility of results and maximises sample recovery. To achieve the dual goals of very fast evaporation, with precise temperature control to protect environmental samples, the Rocket Synergy Evaporator uses a patented low temperature drying technology to directly heat the sample flasks. By pulling a vacuum on the samples, solvent(s) boil at a low temperature, which is determined by the pressure. The Rocket Synergy Evaporator is equipped with the advanced performance features, such as automated end point detection, Dri-Pure® anti-bumping technology, and accurate temperature regulation to further protect the integrity of your samples. A two-stage cold trap is built into the Rocket Synergy Evaporator, providing high levels of solvent recovery, even with volatile organic solvents. Under the control of the evaporator, the cold trap automatically drains to ensure that high solvent recovery is maintained, no matter what mix of solvents are being removed. The compact Rocket Synergy Evaporator fits neatly onto a laboratory bench or into a fume hood.


Evaporator systems from Genevac are proven to safely prepare samples containing volatile analytes a wide array of food and beverage applications ranging from testing constituents of beverages and gluten levels in Whisky, to pesticide analysis of fruit and vegetables as well as determining vitamin levels in cereals. Quality and safety testing of food and beverages is an area of considerable importance where accurate analytical results are critical. In common with many other applications, careful sample preparation is critical, especially when the analyte of interest is volatile. Concentration technology in Genevac systems has been developed with leading analytical laboratories worldwide. This, with key technologies like DriPure, ensures that samples are concentrated safely and rapidly. Many leading food and beverage laboratories have standardised on the Genevac EZ-2 and Rocket evaporators, often in conjunction with Samplegenie™ technology, because this delivers automation of sample transfer and gives unparalleled sample recovery and inter-test reproducibility with very low standard deviations. Samplegenie™ is a great aid to concentration because samples can be concentrated directly into the analysis vial. The system detects when the solvent level enters the vial and, once validated, the method will then concentrate the sample to the required level. If a precise volume is required in the vial, then the sample can be over concentrated and then made up to the desired level with pure solvent.


Shimadzu, one of the world leaders in analytical instrumentation, has released its GCMS-QP2020 high-end single quadrupole gas chromatograph mass spectrometer. With excellent performance and smart operability, the instrument satisfies a wide range of needs for single quadrupole GC-MS systems. The GCMS-QP2020 achieves the highest sensitivity in its class and enables high-speed performance for many applications. The new turbomolecular pump with improved exhaust efficiency provides higher accuracy in analysis, even when hydrogen or nitrogen in addition to helium is applied as the carrier gas. The GCMS-QP2020 also features a function enabling switching of ionization modes without stopping the mass spectrometer as well as ultra-fast scan performance, which allows the use of various analytical conditions. The GCMS-QP2020 with Shimadzu's many specialized databases and application software enables configura¬tions tailored to a multitude of applications and purposes. The GCMS-QP2020 provides not only high-sensitivity and high-speed performance, but can also be used for a wide range of applications with enhanced, specialized databases designed for specific purposes, including the testing/inspection of food, pharmaceutical, chemical as well as the environmental applications. Beyond the GCMS-QP2020, Shimadzu offers the entry model GCMS-QP2010 SE and the flagship GCMS-TQ8040 triple quadrupole model to satisfy all types of laboratory requirements.


JPK Instruments, a world-leading manufacturer of nanoanalytic instrumentation for research in life sciences and soft matter, reports on the breadth of research applications where their NanoWizard® AFM system is being used in the Smart Interfaces in Environmental Nanotechnology Group under the leadership of Associate Professor, Rosa M Espinosa-Marzal. Dr Rosa M Espinosa-Marzal is an Associate Professor in the Department of Civil & Environmental Engineering at the University of Illinois at Urbana-Champaign. The goal of her research is to design innovative systems and improved materials that can solve environmental problems of our society by applying fundamentals of surface and colloidal science, materials chemistry, and nanotechnology. The central theme of her research group, Smart Interfaces in Environmental Nanotechnology (SIEN), is to design, synthesize, characterize and develop a fundamental understanding of bioinspired materials and of (bio) interfaces, also under nanoconfinement. Atomic force microscopy, AFM, is a vital tool for these studies.


Corning Incorporated has announced that it has completed the previously announced acquisition of Gerresheimer AG’s pharmaceutical glass tubing business and formed an equity venture with Gerresheimer to accelerate Corning innovations in the pharmaceutical packaging market. With operations in Vineland, New Jersey and Pisa, Italy, the acquisition positions Corning as a leading worldwide supplier of glass pharmaceutical tubing. Corning and Gerresheimer have also entered into a 10-year supply agreement for borosilicate tubing. Concurrent with the acquisition, the equity venture will commence operations. “We are pleased to complete these transactions, which create a strong, long-term relationship with Gerresheimer, an established market leader” said Eric S. Musser, executive vice president, Corning Technologies & International. “We anticipate a number of synergies with our global glass operations and existing Life Sciences business”. “We think this is a tremendous opportunity to expand in a growing market with evolving needs for glass” remarked Wendell P. Weeks, chairman, chief executive officer and president. “We are applying our unparalleled glass science capability and precision-forming platform to solve difficult challenges related to pharmaceutical glass, and to create value for our long-time pharmaceutical and biotech customers. Leveraging multiple capabilities where we are already a leader characterizes the strategic and capital allocation framework that we recently shared with investors”.


The company is announcing the expansion of its Purification and Analytical Units to enable synthesis of 30 000 high quality screening library compounds monthly. Such expansion represents the largest development to date of its library synthesis capabilities. Following the year-to-year increasing demand on synthesis of screening libraries from its genuine building blocks, Enamine has added to its Purification Unit 10 brand-new Agilent 1260 preparative HPLC. The new range of instruments allows a much higher separation throughput. The Enamine Purification Unit is equipped now with 14 HPLC chromatographs and can produce over 30 000 samples per month, meeting requirements of its most demanding clients. Valuable aliphatic, Fsp3-rich compounds can, from now on, be systematically supplied according to the industry highest quality standards and within the shortest possible time frame. Besides this investment and to support advances in compound synthesis, Enamine’s Analytical Unit has been upgraded in parallel with new LCMS adding to current 5 devices. The Unit occupies an area of around 650 sq. meters employing 30 highly skilled analytical chemists and performing up to 10000 analyses per day.


Continuous biopharmaceutical manufacturing linking Upstream and Downstream processes can lead to significant productivity improvements and key technologies for implementing such continuous processes have to be synchronized. ChromaCon has presented its Contichrom ®CUBE systems where these modular units can be linked to allow a fully continuous downstream train under a single synchronized process control. A Contichrom ®CUBE module were displayed at the Fraunhofer Institut.