We would like to thank the support of Shenzhen Science and Technology Program (Grant No. KQTD20190929172447117).

CAUTION: Carefully check the properties and toxicities of the chemicals described here for the appropriate chemical handling of the relevant material as per the material safety data sheets (MSDS). Some of the chemicals used are detrimental to health, and special care must be taken. Avoid inhalation and contact with skin of these materials. Please wear the proper PPE during the whole process.
1. Preparation of feeds for continuous flow protocol
<ol>
	<li>Purchase BF3&#183;Et2O with a concentration of 8.1 mmol/mL. Label the glass bottle with 2.5 kg of BF3&#183;Et2O as Feed A.</li>
	<li>Prepare a solution of substrate 1 as Feed B. Add 12.7 L of tetrahydrofuran (THF) to a clean 50 L vessel with a mechanical stirrer. Start the stirrer at 150 rpm, and then add 2-Methylpyridin-3-amine (0.5 kg) carefully to the above vessel. Visually check for complete dissolution. Then stop the stirrer and transfer the solution into a container and label as Feed A. 
	NOTE: Ensure that the water content on the Karl Fischer (KF) reaction of THF is below 0.5% w/w. The water content influences the generation of by-products, such as hydrolyzed OH Imp-1; therefore, anhydrous THF was used. If the water content of the reaction mixture is over 1%, the by-product percentage will increase up to 5%. THF with a &#60;0.5% water content is a normal standard, not strictly for the anhydrous THF standard.</li>
	<li>Prepare a solution of tert-butyl nitrite as Feed C. Add 10.7 L of THF to a clean 50 L vessel with a mechanical stirrer. Start the stirrer with moderate rpm and add tert-butyl nitrite (0.53 kg) to the above vessel. Stir for 10 min. Then transfer the solution into a container and label as Feed C.</li>
	<li>Label a container with 25 L heptane as Feed D. 
	&#8203;NOTE: Ensure that the water content on the KF reaction of heptane is below 0.5%. There are two roles that heptane plays in this protocol: i) to dilute the diazonium salt slurries, which can slow down the gas stream during the diazonium decomposition process; and ii) to remove nonpolar impurities in the distillation process during the first-time phase separation.</li>
	<li>Label a container with 2 L of THF as Feed E, which will be used as washing solution.</li>
</ol>
2. Continuous flow equipment setup
<ol>
	<li>Prepare two modules of a microflow reactor with 9 mL of internal reaction volume, one dynamic mixing tube reactor with 500 mL of internal reaction volume, one constant flow pump with a PTFE pump head, and three constant flow pumps with a 316 L pump head.</li>
	<li>Assemble the equipment according to the process flow sheet shown in Figure 1. Check the mechanical integrity of all the connections between pumps, pipelines, and flow reactors before use.</li>
	<li>For the pumps, set up the following flow rates: pump A at 23.8 mL/min; pump B at 3.4 mL/min; pump C at 22.8 mL/min; and pump D at 50 mL/min.</li>
	<li>Maintain the temperature regulation by setting the jacket outlet temperature of the premixing and diazonium salt formation zone at -5 &#176;C and the jacket outlet temperature of the thermal decomposition zone at 60 &#176;C.</li>
	<li>For an equipment safety check and a leak-test, perform the following steps.
	<ol>
		<li>Place the dosing pipelines of pumps A, B, C, and D into the Feed E bottle. Place the discharging pipeline into the waste collecting bottle.</li>
		<li>Start the pumps A, B, C, and D . Regulate the back pressure up to 3 bars, slowly.</li>
		<li>Observe the stability of each pump, and check all the joints, pipelines, and reactors for any solvent leakage.</li>
		<li>Observe the jacket inlet and outlet temperature of each zone and the real-time inlet pressure of each pump and check whether they are within the target ranges.</li>
		<li>Stop the pumps A, B, C, and D after 10 min of steady state equilibrium.</li>
	</ol>
	</li>
</ol>
3. Continuous flow reaction processing
<ol>
	<li>Place dosing pipelines A, B, C, and D into pumps A, B, C, and D, respectively. Place the discharging pipeline into the waste collecting bottle.</li>
	<li>Start pumps A and B simultaneously and record the time. Start pump C after 30 s and pump D after 8 min.</li>
	<li>Place the discharging pipeline into the product collecting vessel after 10 min of steady state equilibrium.</li>
	<li>Observe and record the temperature of each zone and the pressure of each pump.</li>
	<li>Place dosing pipeline B into Feed E at the completion of Feed B pumping.</li>
	<li>Place the discharging pipeline into the waste collecting bottle. Place dosing pipelines A, C, and D into the Feed E bottle.</li>
	<li>Stop pumps A, B, C, and D after 10 min of the washing process.</li>
</ol>
4. Distillation of organic solvents
<ol>
	<li>Adjust the pH value to 1-2 by adding 4 M HCl into the product collecting vessel at 20-30&#160;&#176;C.</li>
	<li>Separate the aqueous layer to an interim vessel. 
	NOTE: After adding 4 M HCl to adjust the pH value, there are two layers in the vessel. The product was acidified in hydrochloride salt form, which can be dissolved in the bottom aqueous layer, while some nonpolar impurities were dissolved in the upper heptane layer.</li>
	<li>Adjust the pH value of the above separated aqueous layer to 9-10 by adding 20% NaOH aqueous at 20-30 &#176;C.</li>
	<li>Add tert-butyl methyl ether (5.4 L) to the above vessel.</li>
	<li>Stir the mixture for 10 min before letting the mixture stand for another 10 min.</li>
	<li>Partition the mixture between the organic layer and the aqueous layer. Collect the organic layer into a container and discharge the aqueous layer into the separator vessel.</li>
	<li>Add ter-butyl methyl ether (4.6 L) to the separator vessel.</li>
	<li>Stir the mixture for 10 min before letting the mixture stand for another 10 min.</li>
	<li>Partition the mixture between the organic layer and the aqueous layer. Keep the organic layer in the separator vessel and collect the aqueous layer in the waste container.</li>
	<li>Add the first part of the separated organic layer into the separator vessel.</li>
	<li>Wash the combined organic phase with 4% citric acid to pH 4-5.</li>
	<li>Partition the above mixture and transfer the organic layer to distillation equipment.</li>
	<li>Distill the organic solvents at 1 atm and 60 &#176;C, and then vacuum distill (25 mmHg) at 60 &#176;C to obtain the product.</li>
</ol>

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None of the authors within this protocol have any competing financial interests or conflicts of interest.

A continuous flow protocol of the Balz-Schiemann reaction has been successfully performed through a combination of a micro-channel flow reactor and a dynamically mixed flow reactor. This strategy features several advantages compared with the batch process: (i) it is safer with controlled diazonium salt formation; (ii) it is more amenable to a higher reaction temperature, 10 &#176;C versus -20 &#176;C; and (iii) it is more efficient without isolation of the diazonium intermediate, two steps in one continuous process. Spec...

The Balz&#8722;Schiemann reaction is a classic method for replacing the diazonium group with fluorine by heating ArN2+BF4&#8722; without a solvent1,2. The reaction can be applied to a wide variety of aryl amine substrates, making it a generally applicable approach to synthesize aryl amines, which are frequently utilized for advanced intermediates in pharmaceutical or fine chemical industries2,3. Unfortunately, harsh reaction conditions are often employed in the Balz-Schiemann reaction, and the reaction generates potentially explosive aryldiazonium salts4,5,6,7,8. Other challenges associated with the Balz-Schiemann reaction are the formation of side products during the thermal decomposition process and its modest yield. In order to minimize the side product formation, thermal dediazotization can be performed in nonpolar solvents or using neat diazonium salts9,10, which means the aryldizanium salts should be isolated. However, the diazotization of aromatic amines is generally exothermic and fast, which is a risk associated with the isolation of the explosive diazonium salt, especially in large-scale production.
In recent years, continuous flow synthesis technologies have helped to overcome the safety issues associated with the Balz-Schiemann reactions11,12. Although there are some examples of diazotization of aromatic amines using continuous microreactors for deamination at positions para to aryl-chlorides, 5-azodyes, and chlorosulfonylation, these contributions were only reported on a laboratory scale13,14,15,16,17. Yu and co-workers developed a continuous kilo-scale process for the synthesis of aryl fluorides18. They have shown that the improved heat and mass transfer of a flow system would benefit both the diazotization process and the fluorination process. However, they used two separate continuous flow reactors; therefore, the diazotization and thermal decomposition processes were investigated separately. A further contribution was published by Buchwald and co-workers19, where they presented a hypothesis that if the product formation was proceeding through the SN2Ar or SN1 mechanism, then the yield may be improved by increasing the concentration of the fluoride source. They developed a flow-to-continuous stirred tank reactor (CSTR) hybrid process in which the diazonium salts were generated and consumed in a continuous and controlled manner. However, the heat and mass transfer efficiency of a CSTR is not good enough as a tube flow reactor, and a large CSTR cannot be expected to be used with explosive diazonium salts in large-scale production. Subsequently, Naber and co-workers developed a fully continuous flow process to synthesize 2-fluoroadenine from 2,6-diaminopurine20. They found that the exothermic Balz-Schiemann reaction was easier to control in a continuous flow manner and that the tubing dimensions of the flow reactor would influence the heat transfer and temperature control aspects - a tube reactor with large dimensions shows a positive improvement. However, the tube reactor&#39;s scaled-up effect will be notable, and the poor solubility of the polar aryl diazonium salt in organic solvents is troublesome for static tube reactors, which face a blockage risk. Even though remarkable progress has been established, there are still some problems associated with large-scale Balz-Schiemann reactions. Thus, the development of an improved protocol that would provide rapid and scalable access to aryl-fluorides is still significant.
The challenges associated with large-scale Balz&#8722;Schiemann reaction processing include the following:(i)the thermal instability of an accumulated diazonium intermediate over a short time period21; (ii) the long processing times; and (iii) the non-uniform heating or the presence of water in the diazonium fluoroborate, leading to uncontrollable thermal decomposition and increased by-product formation22,23. Additionally (iv) in some flow processing modes, an isolation of the diazonium intermediate is still required due to its low solubility14, which is then fed into a uncontrolled rate decomposition reaction. The risk of handling a large quantity of in-line diazonium salt cannot be avoided. Thus, there is significant benefit in developing a continuous flow strategy to solve the abovementioned problems and avoid both the accumulation and the isolation of the unstable diazonium species.
In order to establish an inherently safer production of chemicals in pharmaceuticals, our group has focused on multi-step continuous flow technology. In this work, we apply this technology to the Balz&#8722;Schiemann synthesis on a kilogram scale in a way that eliminates the isolation of aryl diazonium salts, while facilitating efficient fluorination.

<table><tbody><tr><td>2-Methylpyridin-3-amine</td><td>Raffles Pharmatech Co. Ltd</td><td>C2021236-SM5-H221538-008</td><td>HPLC: &gt;98%, Water by KF &amp;le;0.5%</td></tr><tr><td>316L piston constant flow pump</td><td>Oushisheng (Beijing) Technology Co.,Ltd</td><td>DP-S200</td><td></td></tr><tr><td>BF3.Et2O</td><td>Whmall.com</td><td>B802217</td><td></td></tr><tr><td>Citric acid</td><td>Titan Technology Co., Ltd</td><td>G83162G</td><td></td></tr><tr><td>con.HCl</td><td>Foshang Xilong Huagong</td><td>1270110101601M&amp;nbsp;&amp;nbsp;</td><td></td></tr><tr><td>Dynamically mixed flow reactor</td><td>Autichem Ltd</td><td>DM500</td><td>316L reator with 500 mL of internal volume</td></tr><tr><td>Heptane</td><td>Shenzhen Huachang</td><td>HCH606</td><td>Water by KF &amp;le;0.5%</td></tr><tr><td>Micro flow reactor</td><td>Corning Reactor Technology Co.,Ltd</td><td>G1 Galss AFR</td><td>Glass module with 9 mL of internal volume</td></tr><tr><td>PTFE piston constant flow pump</td><td>Sanotac China</td><td>MPF1002C</td><td></td></tr><tr><td>Sodium hydroxide</td><td>Foshang Xilong Huagong</td><td>1010310101700</td><td></td></tr><tr><td>tert-Butyl methyl ether</td><td>Titan Technology Co., Ltd</td><td>01153694</td><td></td></tr><tr><td>tert-Butyl nitrite</td><td>Whmall.com</td><td>XS22030900060</td><td></td></tr><tr><td>Tetrahydrofuran</td><td>Titan Technology Co., Ltd</td><td>1152930</td><td>Water by KF &amp;le;0.5%</td></tr></tbody></table>

a scalable balz-schiemann reaction protocol in a continuous flow reactor

The demand for aromatic fluorides is steadily increasing in the pharmaceutical and fine chemical industries. The Balz-Schiemann reaction is a straightforward strategy for preparing aryl fluorides from aryl amines, via the preparation and conversion of diazonium tetrafluoroborate intermediates. However, significant safety risks exist in handling the aryl diazonium salts when scaling up. In order to minimize the hazard, we present a continuous flow protocol that has been successfully performed at a kilogram scale that eliminates the isolation of aryl diazonium salts while facilitating efficient fluorination. The diazotization process was performed at 10 &#176;C with a residence time of 10 min, followed by a fluorination process at 60 &#176;C with a residence time of 5.4 s with about 70% yield. The reaction time has been dramatically reduced by introducing this multi-step continuous flow system.

The model reaction is shown in Figure 2. 2-Methylpyridin-3-amine (compound 1 in Figure 2) was chosen as the starting material to prepare 2-methylpyridin-3-fluoride (compound 3 in Figure 2) via the Balz-Schiemann reaction. The experimental parameters were systematically investigated by varying reaction temperature and residence time. Feed A is 0.35 M 2-methylpyridin-3-amine in THF. Feed B is pure BF3&#183;Et2...

Watch this Scientific Journal Video about A Scalable Balz-Schiemann Reaction Protocol in a Continuous Flow Reactor at JoVE.com

A Scalable Balz-Schiemann Reaction Protocol in a Continuous Flow Reactor

A detailed scalable continuous flow protocol is presented to synthesize an aryl fluoride from an aryl amine through the Balz-Schiemann reaction.

The demand for aromatic fluorides is steadily increasing in the pharmaceutical and fine chemical industries. The Balz-Schiemann reaction is a ...

a-scalable-balz-schiemann-reaction-protocol-continuous-flow

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2.9K Views.  Shenzhen Hwagen Pharmaceutical Co., Ltd. Ons protocol is een eenvoudige strategie voor het bereiden van arylfluoride uit arylamine op een continue stroom manier. Het is veilig, controleerbaar en efficiënt. Deze maatregel zou inzicht kunnen geven in de fijnchemie en de farmaceutische industrie, waardoor een veilig en betrouwbaar proces zou kunnen ontstaan.Wees voorzichtig en attent om deze techniek uit te voeren. Lees eerst alle stappen en zoek de details van het werken uit voordat u deze techniek probeert. Om de Balz-Schiema...

Video: A Scalable Balz-Schiemann Reaction Protocol in a Continuous Flow Reactor

Real-time Monitoring of Reactions Performed Using Continuous-flow Processing: The Preparation of 3-Acetylcoumarin as an Example

By using inline monitoring, it is possible to optimize reactions performed using continuous-flow processing in a simple and rapid way. It is also possible to ensure consistent product quality over time using this technique. We here show how to interface a commercially available flow unit with a Raman spectrometer. The Raman flow cell is placed after the back-pressure regulator, meaning that it can be operated at atmospheric pressure. In addition, the fact that the product stream passes through a length of tubing before entering the flow cell means that the material is at RT. It is important that the spectra are acquired under isothermal conditions since Raman signal intensity is temperature dependent. Having assembled the apparatus, we then show how to monitor a chemical reaction, the piperidine-catalyzed synthesis of 3-acetylcoumarin from salicylaldehyde and ethyl acetoacetate being used as an example. The reaction can be performed over a range of flow rates and temperatures, the in-situ monitoring tool being used to optimize conditions simply and easily.

Real-time monitoring allows for fast optimization of reactions performed using continuous-flow processing. Here the preparation of 3-acetylcoumarin is used as an example. The apparatus for performing in-situ Raman monitoring is described, as are the steps required to optimize the reaction.

By using inline monitoring, it is possible to optimize reactions performed using continuous-flow processing in a simple and rapid way. It is also possible ...

Millifluidics for Chemical Synthesis and Time-resolved Mechanistic Studies

Procedures utilizing millifluidic devices for chemical synthesis and time-resolved mechanistic studies are described by taking three examples. In the first, synthesis of ultra-small copper nanoclusters is described. The second example provides their utility for investigating time resolved kinetics of chemical reactions by analyzing gold nanoparticle formation using in situ X-ray absorption spectroscopy. The final example demonstrates continuous flow catalysis of reactions inside millifluidic channel coated with nanostructured catalyst.

Millifluidic devices are utilized for controlled synthesis of nanomaterials, time-resolved analysis of reaction mechanisms and continuous flow catalysis.

Procedures utilizing millifluidic devices for chemical synthesis and time-resolved mechanistic studies are described by taking three examples. In the ...

Bioengineering

Optimization of the Ugi Reaction Using Parallel Synthesis and Automated Liquid Handling

The optimization of a Ugi reaction involving the mixing of furfurylamine, benzaldehyde, boc-glycine and t-butylisocyanide is described. Triplicate runs of 48 parallel experiments are reported, varying concentration, solvent and the excess of some of the reagents. The isolation of the product was achieved by a simple filtration and wash procedure. The highest yield obtained was 66% from 0.4 M methanol with 1.2 eq. of imine. This is significantly above the 49% yield obtained from the initial reaction under equimolar concentration at 0.4 M in methanol. Methanol solutions with reagent concentrations of 0.4M or 0.2M gave superior yields while all solvent systems at 0.07M performed poorly. At 0.2M, methanol and ethanol/methanol (60/40) mixtures were statistically equally good while THF/methanol (60/40) was poor and acetonitrile/methanol (60/40) was intermediate. Good reproducibility of the precipitate yields was obtained in these replicate experiments, allowing for subtle interaction effects to be positively identified.

The Ugi reaction has proved to be a convenient way to quickly create diverse libraries of compounds. It involves the reaction of an amine, an aldehyde, a carboxylic acid and an isonitrile typically in methanol at room temperature. In this video, we utilize a 48-slot Mettler-Toledo MiniBlock equipped with filtration tubes and a Mettler-Toledo MiniMapper automated liquid handler was used to deliver the reagents and solvent. The parameters of interest were the concentration, the solvent composition and the excess of some of the reagents.

The optimization of a Ugi reaction involving the mixing of furfurylamine, benzaldehyde, boc-glycine and t-butylisocyanide is described.  Triplicate runs ...

Biology

Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid

Continuous flow technology has been identified as instrumental for its environmental and economic advantages leveraging superior mixing, heat transfer and cost savings through the &#34;scaling out&#34; strategy as opposed to the traditional &#34;scaling up&#34;. Herein, we report the reaction of diphenyldiazomethane with p-nitrobenzoic acid in both batch and flow modes. To effectively transfer the reaction from batch to flow mode, it is essential to first conduct the reaction in batch. As a consequence, the reaction of diphenyldiazomethane was first studied in batch as a function of temperature, reaction time, and concentration to obtain kinetic information and process parameters. The glass flow reactor set-up is described and combines two types of reaction modules with &#34;mixing&#34; and &#34;linear&#34; microstructures. Finally, the reaction of diphenyldiazomethane with p-nitrobenzoic acid was successfully conducted in the flow reactor, with up to 95% conversion of the diphenyldiazomethane in 11 min. This proof of concept reaction aims to provide insight for scientists to consider flow technology&#39;s competitiveness, sustainability, and versatility in their research.

Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid

Flow chemistry carries environmental and economic advantages by leveraging superior mixing, heat transfer and cost benefits. Herein, we provide a blueprint to transfer chemical processes from batch to flow mode. The reaction of diphenyldiazomethane (DDM) with p-nitrobenzoic acid, conducted in batch and flow, was chosen for proof of concept.

Continuous flow technology has been identified as instrumental for its environmental and economic advantages leveraging superior mixing, heat transfer and ...

Utilization of Stop-flow Micro-tubing Reactors for the Development of Organic Transformations

A new reaction screening technology for organic synthesis was recently demonstrated by combining elements from both continuous micro-flow and conventional batch reactors, coined stop-flow micro-tubing (SFMT) reactors. In SFMT, chemical reactions that require high pressure can be screened in parallel through a safer and convenient way. Cross-contamination, which is a common problem in reaction screening for continuous flow reactors, is avoided in SFMT. Moreover, the commercially available light-permeable micro-tubing can be incorporated into SFMT, serving as an excellent choice for light-mediated reactions due to a more effective uniform light exposure, compared to batch reactors. Overall, the SFMT reactor system is similar to continuous flow reactors and more superior than batch reactors for reactions that incorporate gas reagents and/or require light-illumination, which enables a simple but highly efficient reaction screening system. Furthermore, any successfully developed reaction in the SFMT reactor system can be conveniently translated to continuous-flow synthesis for large scale production.

A protocol for organic reaction screening using stop-flow micro-tubing (SFMT) reactors employing gaseous reactants and/or visible-light mediated reactions is presented.

A new reaction screening technology for organic synthesis was recently demonstrated by combining elements from both continuous micro-flow and conventional ...

Nutrient Regulation by Continuous Feeding for Large-scale Expansion of Mammalian Cells in Spheroids

In this demonstration, spheroids formed from the &#946;-TC6 insulinoma cell line were cultured as a model of manufacturing a mammalian islet cell product to demonstrate how regulating nutrient levels can improve cell yields. In previous studies, bioreactors facilitated increased culture volumes over static cultures, but no increase in cell yields were observed. Limitations in key nutrients such as glucose, which were consumed between batch feedings, can lead to limitations in cell expansion. Large fluctuations in glucose levels were observed, despite the increase in glucose concentrations in the media. The use of continuous feeding systems eliminated fluctuations in glucose levels, and improved cell growth rates when compared with batch fed static and SSB culture methods. Additional increases in growth rates were observed by adjusting the feed rate based on calculated nutrient consumption, which allowed the maintenance of physiological glucose over three weeks in culture. This method can also be adapted for other cell types.

Nutrient regulation using continuous growth adjusted feeding improves growth rates of mammalian cell spheroids compared to intermittent batch feeding for cultures in stirred suspension bioreactors. This study demonstrates the methods required for establishing simple adjusted rate fed cultures.

In this demonstration, spheroids formed from the &#946;-TC6 insulinoma cell line were cultured as a model of manufacturing a mammalian islet cell product ...

Generic Protocol for Optimization of Heterologous Protein Production Using Automated Microbioreactor Technology

A core business in industrial biotechnology using microbial production cell factories is the iterative process of strain engineering and optimization of bioprocess conditions. One important aspect is the improvement of cultivation medium to provide an optimal environment for microbial formation of the product of interest. It is well accepted that the media composition can dramatically influence overall bioprocess performance. Nutrition medium optimization is known to improve recombinant protein production with microbial systems and thus, this is a rewarding step in bioprocess development. However, very often standard media recipes are taken from literature, since tailor-made design of the cultivation medium is a tedious task that demands microbioreactor technology for sufficient cultivation throughput, fast product analytics, as well as support by lab robotics to enable reliability in liquid handling steps. Furthermore, advanced mathematical methods are required for rationally analyzing measurement data and efficiently designing parallel experiments such as to achieve optimal information content.
The generic nature of the presented protocol allows for easy adaption to different lab equipment, other expression hosts, and target proteins of interest, as well as further bioprocess parameters. Moreover, other optimization objectives like protein production rate, specific yield, or product quality can be chosen to fit the scope of other optimization studies. The applied Kriging Toolbox (KriKit) is a general tool for Design of Experiments (DOE) that contributes to improved holistic bioprocess optimization. It also supports multi-objective optimization which can be important in optimizing both upstream and downstream processes.

This manuscript describes a generic approach for tailor-made design of microbial cultivation media. This is enabled by an iterative workflow combining Kriging-based experimental design and microbioreactor technology for sufficient cultivation throughput, which is supported by lab robotics to increase reliability and speed in liquid handling media preparation.

A core business in industrial biotechnology using microbial production cell factories is the iterative process of strain engineering and optimization of ...

Synthesis and Discovery of Phosphonate-Based MOFs: A Solvothermal Approach

Discovery and Synthesis Optimization of Isoreticular Al(III) Phosphonate-Based Metal-Organic Framework Compounds Using High-Throughput Methods

High-throughput (HT) methods are an important tool for the fast and efficient screening of synthesis parameters and the discovery of new materials. This manuscript describes the synthesis of metal-organic frameworks (MOFs) from solution using an HT reactor system, resulting in the discovery of various phosphonate-based MOFs of the composition [Al2H12-x(PMP)3]Clx&#8729;6H2O (H4PMP = N,N &#39;-piperazine bis(methylenephosphonic acid)) for x = 4, 6, denoted as Al-CAU-60-xHCl, containing trivalent aluminum ions. This was accomplished under solvothermal reaction conditions by systematically screening the impact of the molar ratio of the linker to the metal and the pH of the reaction mixture on the product formation. The protocol for the HT investigation includes six steps: a) synthesis planning (DOE = design of&#160;experiment) within the HT methodology, b) dosing and working with in-house developed HT reactors, c) solvothermal synthesis, d) synthesis workup using in-house developed filtration blocks, e) characterization by HT powder X-ray diffraction, and f) evaluation of the data. The HT methodology was first used to study the influence of acidity on the product formation, leading to the discovery of Al-CAU-60&#8729;xHCl (x = 4 or 6).

Author Spotlight: Accelerating Discovery in Microporous Material Chemistry 

The targeted synthesis of new metal-organic frameworks (MOFs) is difficult, and their discovery depends on the knowledge and creativity of the chemist. High-throughput methods allow complex synthetic parameter fields to be explored quickly and efficiently, accelerating the process of finding crystalline compounds and identifying synthetic and structural trends.

High-throughput (HT) methods are an important tool for the fast and efficient screening of synthesis parameters and the discovery of new materials. This ...

Process Optimization using High Throughput Automated Micro-Bioreactors in Chinese Hamster Ovary Cell Cultivation

Optimization of bioprocesses to increase the yield of desired products is of importance in the biopharmaceutical industry. This can be achieved by strain selection and by developing bioprocess parameters. Shake flasks have been used for this purpose. They, however, lack the capability to control the process parameters such as pH and dissolved oxygen (DO). This limitation can be overcome with the help of an automated micro-bioreactor. These bioreactors mimic cultivation at a larger scale. One of the major advantages of this system is the integration of the Design of Experiment (DOE) in the software. This integration enables establishing a design where multiple process parameters can be varied simultaneously. The critical process parameters and optimum bioprocess conditions can be analyzed within the software. The focus of the work presented here is to introduce the user to the steps involved in process design in the software and incorporation of the DOE within the cultivation run.

Here, we present a detailed procedure to run a Design of Experiment in an automated micro-bioreactor followed by cell harvest and protein quantification using a Protein A column.

Optimization of bioprocesses to increase the yield of desired products is of importance in the biopharmaceutical industry. This can be achieved by strain ...

Batch and Continuous Bioreactors

Bioreactors are used to grow organisms in large volumes, thereby enabling the production of mass quantities of the target product. These reactors can be batch reactors, which contain all of the components needed for cell growth, or continuous reactors, which have inlet and outlet ports allowing for the addition of fresh growth media and the removal of cell waste.
This video presents batch and continuous reactors&#160;and demonstrates the use of bioreactors to grow bacteria in the laboratory. Finally, this video considers how these reactors are used in the bioengineering field to produce products such as protein therapeutics or even beer.

Principles and Applications of Batch and Continuous Bioreactors

Bioreactors are used to grow organisms in large volumes, thereby enabling the production of mass quantities of the target product. These reactors can be ...

A Scalable Balz-Schiemann Reaction Protocol in a Continuous Flow Reactor

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