Prometheus has been chosen by the scientific community because it consistently delivers high-resolution data that reveals liabilities in drug candidates missed by other technologies. No other system offers simultaneous, multi-parameter characterization throughout the entire run — measuring thermal unfolding, particle sizing, and aggregation — as well as chemical denaturation for a stability profile of unmatched detail.

Prometheus consistently delivers trustworthy, high-resolution stability characterization

Get precise, high-resolution data and reliable results every time
Measuring with precision matters when there are tiny differences between your candidates. Prometheus delivers the kind of stability data you need to clearly see those differences and makes it easier to decide which candidates are best to work with moving forward.

Perform simultaneous measurements with the same samples throughout the entire run
Since you’re doing multi-parameter characterization on the same samples in the same run, you gain a deeper understanding of your molecule’s behavior when correlating your conformational and colloidal stability results.

Choose your throughput, and then choose manual or automated
Be prepared to handle any project that comes your way. Characterizing stability at different checkpoints in your workflow calls for flexible throughput — early development stages require characterizing more candidates than later, during formulation. Choose to run any number of samples from 1 to 48 or 24 at a time. Add automation and do 1536 before having to reload.

Measure label-free under native conditions
Prometheus detects intrinsic fluorescence so you don’t have to introduce dyes and risk interference. It gets better — no need for sample dilution or special buffer conditions means very little or no sample prep. And, have viscous samples? No problem.

Where Prometheus is making a difference


Drug discovery & development

Use every time stability needs to be characterized is monitored to rank molecule candidates

Structural biology

Maximize protein solubility and stability before crystallization to dramatically increase its probability of crystallization

Gene Therapy

Differentiate viral vectors serotypes during development and manufacturing based on their thermal stability profiles

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Biologics discovery & development

Compounds screening before affinity-based single-dose screening

Developability assessment

Pre-formulation and formulation

Production & downstream process development

Comparability studies

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Protein expression & purification

Monitor the stability of recombinant proteins during selection of expression clones and chromatographic isolation and purification


Thermal shift assays

Screen compounds during drug development for shifts in thermal unfolding to eliminate compounds that decrease stability


Monitor stability of recombinant proteins during chromatographic isolation and purification

A system for every one of your needs, present or future

It’s important to take into account your evolving needs for stability characterization and throughput. Choosing fully-featured Prometheus Panta gives you the peace of mind of knowing you’ll be ready for projects that demand simultaneous, multi-parameter characterization. If having a path to automation is what you and your stakeholders have in mind, go with the Prometheus NT.Plex.

Prometheus Panta

Choose Prometheus Panta if you want everything under the sun in stability characterization, including thermal unfolding, particle sizing, chemical denaturation, and aggregation.

Prometheus NT.Plex

Your best bet when you want an easy path to automation. Get thermal unfolding and chemical denaturation with optional backreflection for aggregation evaluation.

Prometheus NT.48

Start here for thermal unfolding and chemical denaturation with optional backreflection for aggregation evaluation.

Automated operation for unattended stability characterization

Prometheus NT.Plex plus NT.Robotic Autosampler

The Prometheus NT.Plex is transformed into a system that increases your throughput with unattended operation with the addition of the NT.Robotic Autosampler. A stand-alone all-inclusive system — with robotic arm, enclosure, computer and monitor. Load up to four 384-well plates with 1,536 samples for hands-free characterization of thermal unfolding and chemical denaturation in a single experiment. Get the optional plate temperature control to keep your samples at 4 to 20 °C while they wait in the queue. And the aggregation detection optics is another upgrade to get you complete stability characterization.

Tackle challenging stability characterizations with multiple technologies in one instrument

Prometheus utilizes a number of technologies to characterize thermal unfolding, particle sizing, and aggregation. Each one tells a different story about their stability, and are used for a variety of applications. But they have one thing in common — they are all label-free.


When is it useful?

What does it do?

For monitoring protein purification or hit screening (thermal shift assay) during biologics formulation, developability, production, and manufacturing

It measures thermal unfolding or chemical denaturation under native conditions and label-free by detecting changes in its intrinsic fluorescence during a thermal ramp or in the presence of a chemical denaturant


When is it useful?

What does it do?

For screening recombinant proteins expressed from different constructs, biologics formulation screening, sample optimization for biophysical assays, and characterization of self-interactions

It detects molecule aggregates to determine the size of proteins over a wide concentration range


When is it useful?

What does it do?

Anytime you’re looking at aggregates larger than 12.5 nm radius

It determines aggregation status by measuring light intensity loss due to scattering

Parameters that characterize protein stability and particle sizing

Do you wonder what attributes are used the most when looking at protein stability? These are the parameters researchers look at when characterizing the propensity of proteins to unfold and aggregate in response to binding events, self-interactions, temperature changes, or the presence of certain chemicals.

Thermal Stability

The unfolding transition temperature is the point at which 50% of the protein is unfolded. Proteins with a higher Tm are more stable because a greater input of energy is required to reach the unfolding transition. Because Tm is an accurate and established metric for assessing protein stability, it’s an essential parameter to determine.

The detectable temperature at which a protein begins to unfold. Particularly in temperature-sensitive situations, it’s important to understand when a protein will denature and lose its activity.


Prometheus does it best when it comes to characterizing protein unfolding. In both thermal and chemical denaturation studies, even the most subtle unfolding events are easily seen that other traditional systems simply can’t detect. Best of all, results are not compromised by aggregates in solution. Get higher quality results and gain the ability to make better decisions.


Prometheus offers precise, high-resolution results in protein denaturation studies


Prometheus monitors the intrinsic fluorescence signal of proteins as a measure of their folding state. Fluorescence intensity at a single wavelength (350 or 330 nm) or the F350/330 ratio are plotted against increasing temperature or concentrations of a chemical denaturant to determine the Tm or Cm of a protein.

Chemical denaturation

The concentration of a denaturant that causes 50% of proteins to unfold addresses the relationship between chemical denaturants and proteins. This parameter is useful when studying chemical effects, or when protein stability is tested using denaturants.

The Gibbs free energy of protein unfolding, is a thermodynamic measure of the likelihood a folding event may occur. For a given event, proteins with more negative ΔG are more likely to fold. ΔG also relates protein folding to changes in enthalpy and temperature. Changes in the Gibbs free energy are measured with ΔΔG, which shows the relative stability of a protein at various concentrations.

Particle sizing

The hydrodynamic radius tells how large or small a protein is in a solvated state, making it a biologically relevant parameter since it considers the protein size in the context of its environment. Monitoring the rH is a simple way to identify the oligomeric state of a protein in a preparation and can be implemented during production to identify relevant fractions of purified protein or to check batch to batch consistency of formulations.

The polydispersity index represents the distribution of size populations within a given sample. The numerical value of PDI ranges from 0.0 (for a perfectly uniform sample with respect to the particle size) to 1.0 (for a highly polydisperse sample with multiple particle size populations)

The diffusion interaction parameter (kD) identifies the onset of protein unfolding and its impact on colloidal stability. Positive kD values are a sign of repulsive intermolecular interactions, while negative values indicate attraction. It can be utilized to compare different protein formulations, and use it to select more stable biomolecules.
The diffusion constant at concentration = 0 (D0) is determined from the kD analysis and represents the theoretical diffusion constant at concentration = 0.



Compare size distribution, mean rH, and PDI to identify optimal buffer conditions for your sample and assess sample homogeneity before performing other time-consuming biophysical assays


This is the temperature at which proteins exhibit a tendency to aggregate. Typically, the onset of aggregation correlates with the unfolding of proteins and can be a useful parameter for comparing colloidal stability.


Being confident in what to do next is key to doing great research. The formulation development group at Boehringer Ingelheim realized that having accurate, precise, and high-quality data for both thermal unfolding and aggregation is key to better predicting stability, developability, and longer-term storage of their antibody candidates.

Prometheus provides comprehensive results for any type of proteins — small or large molecules, biologics, enzymes, antibodies, ADCs, and membrane proteins — and is especially good at screening buffer influences or testing formulation and storage conditions. Make better decisions based on more complete stability results.


Prometheus provides comprehensive stability results


Conformational stability doesn’t always correlate with colloidal stability. Here, the lowest pH destabilizes the mAb, yet reduces its propensity to aggregate. Conversely, the highest pH stabilizes the mAb but causes an increase in the level of aggregation. Therefore, selecting a pH between the two extremes may be the better formulation compromise to use.

What researchers look for when selecting an instrument to characterize stability

Characterizing a candidate molecule’s stability with an instrument that has high specificity, high sensitivity, a broad limit of detection, is very accurate as well as very precise, and produces high resolution data makes a huge difference. It allows you to identify or anticipate structural liabilities that render your molecule non-manufacturable. It also helps to minimize costly mistakes like progressing a candidate that will ultimately not make it to the clinic.

With Prometheus, never doubt the quality of your measurements and move forward with confidence knowing your decisions are derived from the highest quality data.


High level of specificity
Distinguishes the signal of your biologic from the signal of the buffer or matrix

High level of sensitivity
Identifies samples and domains with subtle signals

Broad limit of detection
Measures samples at both clinically and developmentally relevant concentrations, including both high and low concentrations

Reports true Tms

Provides reliable results that consistently return the same value with little error consistent and reliable results with small standard deviations or errors that do not vary from day-to-day

High resolution
Detects multiple unfolding events discriminates domains with similar Tms

Discover how Prometheus’s specificity, sensitivity, accuracy, precision, and limit of detection made a difference in biologics stability characterization

Predict biologics developability profiles through early-stage screening.

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Perform comparability studies to validate that changes to manufacturing processes or sites don’t affect the drug product.

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Facilitate and validate engineered stability enhancements. Correlate these with optimization the biologic’s behavior in storage and accelerated degradation assays.

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Software that gives you clear and actionable results


Wondering how long it will take your team to learn to operate a new instrument and to use its software can trigger stress and a feeling of uncertainty. Not if your instrument is a Prometheus. No matter which model you choose, learning how to use it will be effortless with step-by-step guidance through each experiment, the automatic analysis of your data, and much more.


   Panta Control

Because Prometheus Panta measures more parameters simultaneously, Panta Control software is built with more functionality and intuitive user experience. Get automatic determination of the parameters you care about the most. When you decide to measure multiple parameters, queue them in your preferred order for flexibility that adapts to your schedule.

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Precisely determine at which temperature 50% of your protein unfolds (Tm) and when aggregation begins (Tagg) with PR.ThermControl. Since assay setup is 3 steps only and there’s few experimental parameters to set, you’ll be off and generating data quicker than you imagine. Results are automatically generated and color coded so you can easily visualize the results.

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Use PR.ChemControl when you want to evaluate the chemical stability of a protein. It only takes 40 seconds to get data on the energetics of folding (ΔG) and the denaturant concentration at which 50% of the protein is unfolded (Cm). It’s great for getting quick answers on chemical treatments or conditions that influence protein unfolding and stability.




Are you searching for more details on the rates of unfolding and refolding? Maybe you’re finding a need to run more advanced thermal profiles such as isothermal measurements or a thermal cycling. You’ll want to have PR.TimeControl. Your ability to customize thermal treatment assay conditions is one of the best reasons to use it. Feel free to choose between isothermal measurements, incremental temperature cycling or temperature stepping for those advanced protein stability measurements you’ve always wanted to do.


PR.Stability Analysis

If making more precise conclusions about the stability of your proteins is your ultimate goal then there’s no better way to do that than with PR.Stability Analysis software. Use it to quickly visualize and identify any key trends by sorting, filtering or plotting data as you need. Choose to merge replicates or compare runs. Then conveniently export your results in ready-made formats for bookkeeping, presentation or publication.

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21 CFR part 11

Prometheus PR.ThermControl and PR.AutoThermControl software support 21 CFR Part 11 compliance for regulated environments. These 21 CFR Part 11 compliant software provide electronic signatures, audit trail with record of all activities, and user permissions and access management.

Get consistency with high performance consumables

You don’t have to worry about a long list of consumables to run your stability assays . All you’ll need is capillaries — but not just any capillaries, because only high quality consumable will deliver consistent results. Prometheus capillaries are manufactured using the same stringent protocols used for diagnostic-grade capillaries to ensure the best results. They come as individual capillaries for manual loading of up to 48 samples. Or in chips – each with 24 capillaries – for your Prometheus Panta and PR.Plex.


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