Tag Archives: Biopharm

Boost Bioprocessing Efficiency by Choosing the Right Gas Mass Flow Controller

We can all agree that our economics and external drivers have changed in the last four weeks. The emergence of COVID-19 has changed the way we work, socialize and think about the world. In Sierra’s 45 year history, we also have not seen such a shift in our flow control industry from a slower-moving mature market to critical demand for instruments. Demand for accurate gas flow control for the fast-moving bioprocessing industry is now at the center of our economics. Scientist are fighting hard to quickly find a vaccine for COVID-19, ventilator manufactures are ramping up production to supply hospitals with this life saving equipment, and R&D labs have never been more valued by our country. Single-use bioreactors to full-scale production bioreactors require stable and repeatable gas supply systems to deliver a precise supply of oxygen to the bioprocess. Stable gas flow control maximizes cell culture yields and lowers bioprocessing costs. Due to the critical nature of the biotechnology industry, it’s essential to select the best bioprocessing mass flow controllers for your bioprocessing solutions.

Choose the Best BioProcessing Mass Flow Controller

Researchers must control the gas flow variables into their experiments to trust the data. Most biopharm mass flow controllers have an accuracy +/- 1.0% of full scale, but few can claim long-term sensor stability. Some thermal mass flow controllers are based on MEMs (Micro-Electro Mechanical Systems) technology utilizing an advanced ultra-stable no-drift CMOS (Complementary Metal Oxide Semiconductor) sensor. MEMS sensors don’t drift over time which can be a huge competitive advantage in bioprocessing OEM applications where long term stability is essential. Sierra’s MEMS bioprocessing MFCs offer a lifetime, no drift sensor warranty to ensure stability which increases bioprocessing efficiency.

Modularity & Flexibility

For OEMs and research manifold systems, the “plug & play” design of some bioparm mass flow controllers make it easy to integrate into a bioreactor design or set up a gas flow control manifold. Modular design allows flow controllers to be stacked into a gas block with a minimal footprint. Inlet and outlet configurations are flexible and can be easily integrated into your instrumentation, like bioreactors. Easy connect power and cabling systems make set up painless and can adapt to specific requirements with both analog and digital options.

Easy Communications

For ease of use, a local display readout that communicates key flow data is important along with the ability to configure via software. Modbus RTU and analog outputs, and industrial ethernet (EtherCat and Profibus) make it more efficient to communicate and integrate with your system.

Fast Delivery

Most flow meter companies have a standard lead time of 4-6 weeks. But there are times you need a flow controller fast. Some MFCs are available online for next day delivery and localized support. Sierra’s online store offers all mass flow meters and controllers for next day shipment. Sierra’s RedySmart MEMS mass flow controller is the ultimate biopharm mass flow controller, offering a lifetime no-drift sensor warranty, modular design, and easy to connect communications. Now more than ever we do “understand flow is tough”. But we CAN solve this together. We can solve any gas flow control challenge you may have with our team of engineers. Watch the video to learn more: RedySmartTM : The Ultimate OEM Mass Flow Controller

Mass Flow Controllers Support Ventilator Testing

Precision Mass Flow Control Validates Ventilator Accuracy

It’s actually a life and death matter, and we take this very seriously. Accurate mass flow control is crucial in the process of validating the accuracy of oxygen flow for mechanical ventilators and respiratory medical equipment. Ventilators are designed to pump oxygen into a patient that is breathing insufficiently or unable to breathe on their own. A ventilator machine moves air into and out of a patient’s lungs to ensure their body receives the oxygen it needs to survive, and hopefully recover from the effects of the COVID-19 virus.1  To make sure patients are getting the exact amount of oxygen needed, in the field ventilators must be meticulously validated to each flow range in order to be effective.

Proven & Accurate Testing for Respiratory Equipment You Can Trust

With over 20 years of proven performance, Sierra is known for providing scientists with precision mass flow control and the ultimate lab research flexibility.  Every Sierra SmartTrak 100 has a wide operating flow range and pressure requirements and is pre-programmed for up to 10 gases that are field selectable. Because of this, Sierra’s SmartTrak is used as a validation standard in order to verify that the ventilators are performing within specification. For ease of use, scientists can easily change set points, flow rates, engineering units on directly on the push-button display or remotely with the Pilot Module. For particularly challenging applications, Sierra’s dedicated engineering team can provide custom engineering solutions to meet precise customer requirements.

The heart of the SmartTrak 100 mass flow controller is a platinum-wound capillary sensor that directly measures thermal mass flow. Sierra’s patented laminar flow element eliminates non-uniformities and conditions the flow in the capillary sensor into stable laminar behavior where mass flow measurement occurs.

Key SmartTrak 100 Features

  • All clean gases including toxics and corrosives
  • Accuracy – Standard: +1.0% of full scale, High Accuracy – Up to +0.5% of full scale
  • Repeatability – +0.2% of full-scale
  • Multi-Gas – Preprogrammed for up to 10 gases – Field selectable
  • Flow Range – 0 to up to 1,000 slpm
  • Local/remote display and pushbutton interface
  • Buy Online-Fast Next Day delivery

Learn how Sierra’s mass flow controllers are used to accelerate Bioprocessing from Pilot to Full-Scale Production.



  1. Sonas Home Health Care, June 28, 2018,  “What is a Mechanical Ventilator?” https://www.sonashomehealth.com/medical-ventilator/ .

Why Mass Flow Controllers are Replacing VA Meters in Bioreactors

Upgrading to A Gas Mass Flow Controller Provides Greater Reliability for your Bioreactor

When it comes to efficient bioreactor performance, precision mass flow control gas is critical. It is essential that bioreactor manufacturers have reliable, repeatable, and flexible gas supply systems for their bioreactors.  Due to the ever-evolving demands and critical and complex nature in the bio-industry, VA meters commonly used in this application are no longer suitable and bioreactor manufacturers are now turning towards mass flow controllers to strengthen their process.

Bioreactor Application Challenges

Reliable and stable control of the supply of oxygen to the bioreactor is a complex process. The metabolism of the microorganisms is dependent on the dissolved oxygen concentration, so that a precise gas flow control is critical. Therefore, the oxygen concentration must be lowered or increased as required (mixture of N2 or O2).

Another important variable is the pH value. For microbial bioprocesses this is done with the addition of liquid acids and alkalis. For cell cultures, on the other hand, one uses only liquid alkalis. The liquid acid can damage the cells so you use CO2 instead of liquid acid. There are many different bioreactor processes and each has its specific reason to use and control gasses, but they all require precision gas flow control for optimal metabolism of micro-organism which is essential to vaccine testing and development.

VA Meters No Longer A Viable Solution

Traditionally bioreactor manufacturers use VA meters in their bioprocesses.  However, with changing bioreactor technology several major factors are impacting how a mass flow controller in a bioreactor must work eliminating VA meters as a viable option.
  • Miniaturized  design  for  custom  OEM  devices
  • Automated features for higher performance processes
  • Preventing contamination events caused by bioreactors
First, bioreactors are becoming smaller. Miniaturized stirred tank bioreactors are cost-effective solutions for biotechnology industries that require rapid process developments for smaller-scale experimentations. These bioreactors provide a cost-effective approach that requires consistent, accurate gas flow measurements that can adapt automatically to changing pressures and temperatures.
Secondly, technology is becoming more automated. Bioreactors have high-performance needs as the equipment requires components that can offer repeatability through automation. Relying on manual adjustments impacts productivity as well as increases process costs.
Another major factor regards bacteria contamination from bioreactors. In cleanroom environments, contamination events can create lost batches  in cultures,  lost production time,  compliance issues,  and increased decontamination costs. Using materials that are less prone to contamination or corrosion lowers the risks of a contamination event from occurring.
The legacy design of a VA meter has simply not kept up with the changing technologies that have become available for bioreactors. Manual VA meter controls cannot handle the rapid processes that are needed in the industry while also maintaining reliability and accuracy. High-performance processes will require more automated solutions — ones which the present VA meter cannot provide.
In addition, a VA meter does not come with an output signal and they are not suitable for automatization of your process.  VA meters are extremely sensitive to changes in pressure and temperatures, and a small change in these parameters creates a relatively big error in the indicated mass flow.  This uncertainty creates non-repeatability in your process. Mass flow controllers measure true mass, independent of pressure and temperature, constantly providing an accurate gas mass flow control.

Rock Solid Mass Flow Control Improves Bioreactor Performance

Sierra’s proven line of mass flow controllers for bioprocessing meets the rigorous demands of the bioprocess industry and supports scientists and manufacturers. RedySmart mass flow controllers provide critical gas flow control systems for bioreactors to scale vaccines from lab to pilot to full-scale production.
As we know, bioreactors require precision mass flow control of the gases used to feed the biomass and to ensure proper mixing and distribution. This ensures healthy fermentation.

Smart Design

Combining superior physics, high reliability, and unparalleled flexibility, RedySmart stands apart from competitive offerings.  The RedySmart thermal mass flow meters & controllers are MEMS-based (Micro-Electro Mechanical System) technology. RedySmart thermal mass flow devices contain no moving parts and are unaffected by upstream temperature and pressure fluctuations, resulting in exceptional accuracy and repeatability.  The RedySmart offers a true OEM mass flow control solution with its modular design, cabling system, easy integration into a gas mixing block, and a wide array of digital communications options (Modbus included with no additional charge).  In addition, they are completely automated.

These design capabilities allow for smaller custom sizes that can accommodate different bioreactor sizes, including the miniaturized stirred bioreactors that are becoming the present industry trends.

Maximum Production Stability

RedySmart comes with an ultra-stable no-drift Complementary Metal Oxide Semiconductor (CMOS) sensor to assure maximum production stability required by bioprocessing OEMs. Sierra also offers a lifetime no-drift sensor warranty on the sensor. This feature provides greater production stability for bioprocessing OEMS where long term stability is key. If drift occurs, the sensor will be replaced or repaired free of charge.

Sierra also offers modular customization for bioreactor OEM designs. Many bioreactors will be manufactured to meet the specific needs of the process application. The bioreactors may require standard gases such as O2, N2 or air as well as non-toxic and non-corrosive gases. One RedySmart controller can handle up to 10 gases for just one device. Engineers can obtain flow ranges from 0 to 500 slpm (nlpm) and pressures of 3 – 160 psia (0.2 -11 bara). In addition, our gas flow controllers also handle gas and ambient temperatures ranging from 32 -122°F (0 – 50°C).

RedySmart Advantage

  • Ultimate OEM MFC-modular, compact footprint, connect power cable & communication system
  • MEMS sensor stability- Lifetime no-drift sensor warranty
  • Direct mass flow with thermal technology- no temp or pressure compensation
  • Precision electromagnetic valve control
  • Competitive OEM pricing- Cost-effective solutions
  • Built-in display-mass flow, totalizer, units, set point
  • Human & Systems Interface-local display readout, configure in field
  • Fast Set Point Control- response times as fast as +/-80ms
  • Response time: Meter (GSM): ± 80ms(3); Controller (GSC): ± 500ms(3)

Improved Accuracy

Accurate processes that can be repeated is essential for an automated, high performance bioreactor mass flow controller. Our Sierra  RedySmart MEBS-based mass flow controller offers a standard accuracy of +/- 1.0% of full scale and a high accuracy of up to ± 0.3% of full scale ±0.5% of reading. The controller also offers repeatability of +/- 0.2% of full scale. These higher accuracy ratings are due to our real gas calibration technologies for a wider range of gases.

With Sierra’s RedySmart bioreactor mass flow controller, engineers can replace their old VA meters when requiring more stability, accuracy and performance in their flow measurements. The automated features and components offer long term stability and higher performance at more cost-effective prices.

How Do MEMS Mass Flow Controllers Work?

Not All MFC Sensor Technology is Created Equal

Mass flow controllers offer precision gas flow control to many critical industries including biopharm, semicon, food & beverage, manufacturing, and R&D. As the technology demands increase in these sectors, so does the demand for precision gas flow control systems. The more accurate and repeatable the gas flow control the better the yield, the higher the product quality and the lower the cost in wasted materials.

So what mass flow control technology offers the highest accuracy and repeatability over time? MEMS (Micro-Electro Mechanical Systems) sensors offer the most stable and accurate gas flow control in the industry. Mass flow controllers and meters based on MEMS technology don’t drift like other technologies, offering OEMs and bioprocessing applications a mass flow controller that is accurate over the lifetime of the device-no yearly recalibration or process shutdown necessary.

How does MEMS technology work to ensure a “no-drift” mass flow controller?

MEMS Principle of Operation

MEMS technology utilizes an advanced, ultra-stable, no-drift CMOS (Complementary Metal Oxide Semiconductor) sensor. The CMOS sensor houses both the electronic circuits and mechanical elements on a silicon chip, similar to the process used for integrated circuits.

Sierra’s RedySmart MFC – MEMS Sensor at 50x Amplification view

MEMS technology is based on the thermal principle of operation. MEMS sensors consist of two or three temperature sensors and a heater. Through vapor deposition, an extremely small molecular layer is deposited on a thin membrane. MEMS-based mass flow controllers have a bypass that pushes a defined percentage of the total gas flow through the sensor. The bore of the sensor is fairly large, so that the pressure drop is relatively low. In the presence of flow, the MEMS chip introduces heat into the medium with a constant heating output. The two temperature sensors are arranged symmetrically before and after the heating element to detect a shift in the temperature profile towards the downstream sensor of the heating element. If there is no flow, both sensing elements measure the same temperature. Because the sensor is part of the MEMS electronic circuit, the measured signal is immediately digitized giving direct mass flow readings.

Why Mass Flow is Critical

Measuring mass flow is important since most processes are more directly related to mass flow rather than to volumetric flow. For respiration, fermentation or any chemical process, it is that number of oxygen molecules that are critical, mass not volume that is critical. Unlike turbine meters, ultrasonic, pressure differential, pitot tubes and many other devices, thermal flow meters measure mass flow. Direct mass flow meters are unaffected by fluctuations in both temperature and pressure which make them inherently more accurate than volumetric technologies.

Benefits of MEMS Mass Flow Controllers

The biggest advantage of the MEMs sensor is that there is no (measurable) drift. Drift is a slow shift of the zero and the measured value at a given flow. Drift affects the accuracy. MEMS sensors are also compatible with its electromagnetic (EM) environment and don’t emit levels of EM energy that cause electromagnetic interference (EMI) distorting the signal. This along with the fact that the sensors are free of mechanical and thermal stress enables a no drift sensor and long-term device accuracy.

Mass flow controllers based on MEMs technology do not have a linear output, so they must be calibrated with the actual gas that is being used in the application. The output is a complex curve that can only be accurately curve-fit with a spline or a polynomial. And every sensor construction varies, so there is no repeatability from sensor to sensor. That means that every flow meter and controller needs to be calibrated individually on actual gas which increases their accuracy.

MEMS sensors are also very fast with a 50 msec response time with virtually no warm-up time. The instrument does not need the zero to be adjusted on regular basis. A MEMS sensor is also a lot more sensitive and due to that a turndown of 1000 : 1 is obtainable.

Benefits of MEMS Sensors

  • No-drift sensor-Long term stability over a long period of use
  • Wide turndown of 100:1. (Higher possible)
  • Less sensitive to pollution due to big ID sensor
  • Excellent temperature coefficient
  • High accuracy due to real gas calibration
  • Low-pressure drop (2.5 mbar at low flow)
  • Built-in flexibility
  • Low power consumption

RedySmart Mass Flow Controller with Lifetime No-Drift Sensor Warranty

Sierra’s RedySmart thermal mass flow meters & mass controllers are based on MEMS-based (Micro-Electro Mechanical System) technology to complement our SmartTrak® capillary-based mass flow meters & gas controllers. RedySmart thermal mass flow devices contain no moving parts and are unaffected by upstream temperature and pressure fluctuations, resulting in exceptional accuracy and repeatability.

RedySmart Proven & Stable Mass Flow Controllers offer OEMS:

  • Lifetime no-drift sensor warranty – if drift occurs, instrument will be repaired or replaced free of charge
  • High Accuracy up to ± 0.3% of full scale ±0.5% of reading
  • Repeatability of +/- 0.2% of full scale
  • Air, N2, O2 are standard. Other non-toxic, non-corrosive gases available upon request.
  • Custom and compact gas mixing blocks
  • MEMS (Micro-Electro Mechanical Systems) with ultra-stable no-drift CMOS (Complementary Metal Oxide Semiconductor) sensor
  • Ideal for OEM Applications-optimized for BioPharm/Burner Control
  • Modular-customize to needs. An easy-connect communication and power cable system has been designed for ultimate flexibility

Learn more about MEMS Sensor technology and RedySmart products.

Discover how MEMS sensor technology is providing edge to accelerate bioprocessing from pilot to production.

How Do Biopharm Mass Flow Controllers Optimize Bioreactor Performance?

Our new bioreactor application tech note is worth the download. The new tech note focuses on how digital mass flow controllers optimize bioreactor performance and replace manual variable area (VA meters) with an integrated valve to control the gases in their bioprocesses to yield greater results.

As you know, in today’s climate it is a race against time to create viable vaccines from pilot to scalable vaccine production to fight infectious diseases. In the biopharma world, the efficiency and productivity of bioreactor technology becomes a critical path to this vaccine development.

Learn how MFCs optimize bioreactor performance and check our four tips for selecting the perfect biopharma mass flow controller by downloading the “How Digital Mass Flow Controllers Optimize Bioreactor Performance” application tech note.