A breakthrough in process analytical technology for production of nanoparticles, biopharmaceuticals and polymers.

Real-Time Multi-Angle Light Scattering

ultraDAWN measures multi-angle light scattering and reports the results – weight-average molecular weight Mw and rms radius Rg – in real time. With RT-MALS, critical quality attributes (CQAs) can be monitored directly, for rapid feedback on product and process quality.

Benefits of RT-MALS

  • Accelerate process development and scale-up
  • Increase yield, reduce overall time until lot release
  • Maintain product quality with confidence

Where MALS and PAT meet

The ultraDAWN is a unique member of the DAWN family of MALS instruments. Instead of residing in the analytical lab like Wyatt’s other MALS instruments, it is adapted to pilot plants and production environments. OBSERVER software is used to calculate and report molar mass and size, 30 times per minute, as opposed to ASTRA’s post-separation, detailed off-line analysis and reporting.

PAT instrumentation is well-known and typically monitors process parameters such as pH, temperature, pressure and feedstock, which are tied indirectly to product properties and quality. UltraDAWN revolutionizes process development with its continuous, direct measurements of actual product properties.


With an intelligent user interface indicating molar mass and size alongside system health diagnostics, photodetectors at eighteen scattering angles plus one more to measure light transmitted through the flow cell, the ultraDAWN provides a solution for:

  • Real-time monitoring of Mw from 103 to 109 g/mol and Rg from 10 to 250 nm. For molar mass analysis, the current version of OBSERVER™ software requires fixed analyte concentration and solvent composition
  • Immediate detection of particulate contamination
  • Triggering process endpoints or critical alarms

Process integration options

  • In-line or on-line configuration
  • Process or slipstream flow rates from 0.1 mL/min to 5 mL/min
  • Integration with production control software via OPC

Real-Time Operation

In-line - For continuous processes that take place at flows below 5 mL/min, such as microfluidic drug encapsulation or chromatographic purification steps, in-line RT-MALS provides the shortest feedback loop while the ultraDAWN samples the entire process stream.

On-line - When processing takes place within a fixed volume such as a homogenizer, or when the process flow is greater than 5 mL/min, a bypass stream is diverted from the manufacturing process to the ultraDAWN. RT-MALS data are produced in near-real-time.

At-line / Off-line - For detailed analysis, products can be characterized by techniques such as SEC-MALS or FFF-MALS. These provide complete, high-resolution distributions of molar mass and size, though not in real time. A standard DAWN® MALS instrument is employed along with an SEC system or an Eclipse™ field-flow fractionation system.

ultradawn, in-line monitoring, on-line monitoring



A PAT strategy that incorporates ultraDAWN for RT-MALS sees reduced development time and fewer samples sent to off-line analytical labs. With real-time CQA analysis, process margins can be optimized and attribute drifts detected immediately, reducing discarded product and increasing yield.

RT-MALS in Lab R&D

RT-MALS can be implemented early in process development – at pilot plant scales and even smaller, such as regular production of small batches of material for R&D use. Experience with lab-scale RT-MALS paves the way for effective implementation on the production floor.

RT-MALS in Scale-up from Lab to Manufacturing

Scaling up often means re-developing the process, requiring off-line analysis of numerous samples collected from intermediate and final steps. RT-MALS greatly accelerates scale-up: it provides real-time feedback, indicating the effect of method tweaks on CQAs, while simultaneously reducing effort and the number of samples analyzed off-line.

Unlike complex at-line PAT devices, ultraDAWN can simply be left in the process flow upon completion of scale up, for continuous or periodic monitoring of the final process.

RT-MALS on the Manufacturing Floor

ultraDAWN and OBSERVER software are simple, robust technologies that may be employed in different ways during serial production. During initial stages, technicians can visually monitor molar mass and size, intervening in the process as needed. With increasing confidence in the capabilities and reliability of RT-MALS, engineers may implement fully-automated process control using OBSERVER’s configurable triggers. In both cases, all data can be reviewed post-production to determine if any deviations were encountered.

Case Study 1:

End-point determination of a polysaccharide depolymerization process

Background - Molar mass plays an important role in the solubility, potency, and stability of polysaccharide-based vaccines. The production process includes a critical depolymerization step to reduce the polysaccharide’s initial weight-average molar mass, Mw, from over 1800 kDa down to less than 350 kDa.

Current methods to monitor molar mass during polysaccharide production employ off-line SEC-MALS analysis, during which a single run can take up to 30 minutes. With a typical depolymerization time of about 90 minutes, off-line analytics cannot provide timely feedback on reaching the endpoint. RT-MALS fills this need and ensures that the process ends as soon as the endpoint criterion is achieved.

Implementation - A polysaccharide solution was depolymerized by ultrasonication at 20 kHz. Molar mass was monitored online, in near-real-time, by continuously pumping a small fraction of solution from the reactor through the ultraDAWN. OBSERVER software was configured to send a trigger to stop the sonication if Mw < 350 kDa, as determined by the release specifications.

Result - RT-MALS demonstrably tracked reduction of the polysaccharide’s Mw and triggered reaction shutdown once it fell below 350 kDa. SEC-MALS analysis of the final product confirmed the desired CQA value. Multiple off-line analyses were eliminated, the time spent by the drug substance in this portion of the process was cut by 25%, and total person hours spent in this part of the process was reduced by at least 50%.

ultradawn, real-time molar mass determination, molar mass measurement, molar mass analysis, molecular weight measurement, molar mass characterization, OBSERVER


Case Study 2:

In-line monitoring of liposome size

Background - In liposome and lipid nanoparticle (LNP) drug-delivery applications, particle size is a CQA that impacts bioaccessibility, retention time and biodistribution. Microfluidization is a common method for large-scale production of liposomes within a well-defined size range. The resulting particle size is dependent on a number of process parameters, such as chamber pressure and temperature, which can drift over the course of time.

Current on-line and off-line control methods do not sample the entire lot, and only provide average sizes, potentially hiding pockets of out-of-spec material. RT-MALS ensures batch consistency by in-line monitoring size of the entire batch; the collection stream can be diverted to waste if the particle size falls out of specification.

Implementation - Crude liposome solution containing heterogeneous liposomes with sizes from 150 nm to 800 nm was passed through a microfluidizer. The internal chamber pressure was initially held at 8,000 psig, then changed to 11,000 psig after 25 minutes to simulate an undesirable drift in the manufacturing process. Upon exiting the chamber, the solution passed through the ultraDAWN RT-MALS instrument. OBSERVER was programmed to trigger a diversion of the exit stream if particle size deviated by 2 nm from the nominal CQA value.

Result - Liposome Rg was observed to be 50 nm, constant to within 0.5%, as long as the chamber pressure was maintained at 8,000 psig. The size decreased when the internal chamber pressure was increased to 11,000 psig. OBSERVER successfully triggered diversion of the process stream when the size decreased below 48 nm. Using the standard procedure of final QC testing alone, the entire batch would have been discarded; with RT-MALS-based monitoring and control, only about half the batch was discarded and the rest, which was collected, met specification. In addition, flagging the issue led to re-calibration of the chamber prior to running the next batch, avoiding further losses.

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The case studies are for illustrative purposes only and based on a theorized use case for ultraDAWN. They do not represent specific customer experiments, results or conclusions.


OBSERVER software provides an intuitive display for setting up and monitoring RT-MALS. Run data can be saved and viewed within OBSERVER or exported to a spreadsheet.

OBSERVER, molar mass determination, molar mass measurement, molar mass analysis, molecular weight measurement, molar mass characterization

   Molar Mass Range 1 kDa to 1 GDa1
   Molecular Size Range (Rg) 10 to 250 nm1
   Data Acquisition Range 30 measurements/min
   Accuracy 5%2
   Repeatability 2%
   Solvent Compatibility All-solvent compatible (aqueous and organic). Wetted materials are 316 stainless steel, fused silica and Kalrez.
   Maximum Flow Rate 5 mL/min @ 1 cP3
   Maximum Viscosity 30 cP
   MALS Detectors High-gain, high dynamic range photodiodes at 18 detection angles.
   Analog Inputs 4 differential analog inputs with 24 bit resolution. Input range -10 V to +10 V
   Analog Outputs 2 analog outputs from user selectable measurements channels -10 V to +10 V
   Other Inputs/Outputs Alarm in, Alarm out/retransmit
   Computer Interface  Ethernet
   Front Panel Display 257 mm, 24-bit color, high-resolution touch screen for instrument control, signals and diagnostics. May be used with gloves.
Dimensions 58 cm (L) x 36 cm (W) x 26 cm (H)

1Depending on dn/dc, the sample concentration and process conditions, this is typical.

2Assuming sample and ambient temperature are at calibration temperature, typically 21 °C. Accuracy margin increases to 6% when ambient temperature deviates by 5 °C from calibration temperature, and to 7.5% when sample temperature deviates by -5/+7 °C from calibration temperature.

3Maximum flow rate decreases with viscosity.

Host PC requirements may be found in Computer Requirements.

Specifications subject to change without notice.

Other MALS Instruments

 dawn, molar mass determination, molar mass measurement, molar mass analysis, molecular weight measurement, molar mass characterization

DAWN® - The most sensitive MALS detector available, anywhere. Incorporates detectors at 18 angles to determine molar masses from 200 Da to 1 GDa and radii from 10 – 500 nm.

  • Standard option: ambient temperature
  • Heated/cooled option: -15°C to +150°C
  • High-temperature option: ambient to +210°C

The DAWN offers special options to handle fluorescent samples: fluorescence-blocking filters and an infrared, 785 nm laser.

miniDAWN® - Second only to the DAWN in sensitivity. Incorporates detectors at 3 angles to determine molar masses from 200 Da to 10 MDa and radii from 10 – 50 nm. Ambient only.

microDAWN™ - The first MALS detector for UHPLC, with interdetector dispersion as low as 1.5 µL. Incorporates detectors at 3 angles to determine molar masses from 200 Da to 20 MDa and radii from 10 – 50 nm. Ambient only.