IMDNA • Assay Strategy • Feasibility • Design • Proof of Concept

Assay Feasibility & Design

De-Risk the Scientific Question Before Full Assay Development

IMDNA helps research teams determine whether a proposed molecular or protein assay is scientifically and analytically feasible before committing resources to full development. Feasibility work can evaluate the biological target, analyte form, expected abundance, specimen matrix, technology, critical reagents, controls, workflow constraints, multiplex potential, and preliminary analytical behavior.

Programs can support qPCR/RT-qPCR, ELISA, multiplex bead-based immunoassays, multiparameter flow cytometry, and cell-based functional assays, as well as integrated biomarker strategies that connect nucleic-acid, soluble-protein, cellular-phenotype, and functional-response measurements. The objective is not to declare an assay “validated” at the feasibility stage, but to generate enough evidence to make an informed go, modify, split, or stop decision and define the most defensible development path.

Question → analyte → matrix → technology → prototype → feasibility evidence → development decision.
Scientific Fit

Is the Analyte Appropriate?

Evaluate whether DNA, RNA, protein, antibody, antigen, soluble biomarker, or another measurable endpoint actually answers the research question.

Technical Fit

Can It Be Measured Reliably?

Assess expected abundance, specificity, dynamic range, matrix effects, reagent availability, and platform constraints.

Workflow Fit

Will the Assay Work in the Intended Matrix?

Evaluate specimen collection, processing, stability, extraction, dilution, interference, sample volume, and throughput.

Prototype

Proof-of-Concept Testing

Build and challenge an initial assay configuration before committing to extensive optimization or validation.

Decision

Define the Development Path

Advance, redesign, change technology, split a multiplex, change matrix, or discontinue low-value approaches based on evidence.

What “Assay Feasibility” Means Scientifically

The NIH/NCATS Assay Guidance Manual describes assay development as an iterative process in which the assay format, reagents, sensitivity, dynamic range, stability, artifacts, interference, instrumentation, and performance statistics are considered in relation to the intended purpose. Feasibility therefore sits before formal validation: it is the structured process of determining whether the proposed biology and analytical system can realistically support the intended measurement.

Biological Feasibility

Is the proposed analyte mechanistically connected to the research question? Is it present in the selected tissue or biofluid? Is the analyte expected to change on the timescale, in the population, or under the experimental conditions being studied?

Analytical Feasibility

Can the analyte be measured with sufficient specificity, sensitivity, range, precision, and signal-to-background using the proposed technology and available reagents?

Matrix Feasibility

Will the intended specimen support the measurement? Matrix constituents can inhibit PCR, alter antibody binding, affect recovery, change apparent concentration, or destabilize the analyte.

Operational Feasibility

Can the workflow meet practical requirements for sample volume, turnaround, multiplexing, instrumentation, operator complexity, reagent stability, throughput, cost, and transfer to the intended laboratory environment?

Core Questions Addressed During Feasibility & Design

A well-designed feasibility study converts an idea into explicit technical questions that can be answered experimentally.

What Is the Intended Research Use?

Define exactly what decision, comparison, biological mechanism, or research endpoint the assay is expected to support.

What Is the True Analyte?

Clarify whether the relevant measurement is genomic DNA, RNA, splice variant, fusion transcript, protein, active enzyme, antigen, antibody, cytokine, or another molecular form.

Where Is the Analyte Measurable?

Evaluate tissue, whole blood, plasma, serum, PBMCs, saliva, urine, swab, FFPE, cell supernatant, bone marrow, environmental matrix, or another specimen.

What Abundance Range Is Expected?

Estimate whether endogenous concentrations are likely to fall within a usable quantitative or detection range and whether diseased/treated samples may differ substantially from controls.

How Specific Must the Assay Be?

Consider paralogs, isoforms, homologous organisms, related variants, cross-reactive proteins, heterophilic antibodies, or other potential analytical confounders.

Which Technology Fits the Biology?

Select qPCR/RT-qPCR for targeted nucleic acids, ELISA for focused proteins, or multiplex immunoassay for multianalyte soluble-protein research when appropriate.

Can Critical Reagents Be Obtained?

Assess primer/probe designability, antibody specificity, recombinant standards, calibrators, control materials, reference samples, and lot continuity.

What Are the Likely Interferences?

Identify PCR inhibition, extraction loss, matrix binding, proteolysis, hemolysis, lipemia, heterophilic effects, cross-talk, nonspecific signal, or competing targets.

Can the Assay Be Multiplexed?

Evaluate target abundance differences, spectral channels, oligonucleotide interactions, shared chemistry, assay ranges, antibody cross-reactivity, and matrix compatibility.

What Controls Are Needed?

Map each major failure mode to a control: extraction/process, inhibition, no-template, no-RT, positive, negative, calibrator, endogenous, exogenous, or QC materials.

What Performance Is Actually Needed?

Set preliminary expectations for specificity, sensitivity, range, precision, robustness, recovery, parallelism, or other characteristics according to intended use.

What Would Make the Concept Nonviable?

Define failure criteria before testing so that the feasibility study can support a real decision rather than becoming open-ended optimization.

Technology-Specific Feasibility Strategy

The feasibility questions are different for nucleic-acid assays and ligand-binding assays. The platform should follow the analyte—not the other way around.

qPCR / RT-qPCR Feasibility

Key questions: Can a specific amplicon be designed? Is the target sufficiently conserved or unique? Is RNA quality adequate? Will the expected target abundance fall within the useful range?

  • Sequence and transcript-definition review
  • Primer/probe designability and in-silico specificity
  • Singleplex proof of concept
  • Amplification efficiency and dynamic-range screening
  • Matrix inhibition and extraction feasibility
  • Preliminary LOD/LLOQ where relevant
  • Reference-gene feasibility for expression studies
  • Multiplex compatibility assessment

Scientific basis: MIQE 2.0 and ISO 20395 emphasize assay design, specificity, efficiency, dynamic range, controls, detection/quantification limits, normalization, and robustness as core qPCR performance considerations.

ELISA Feasibility

Key questions: Is the protein detectable in the intended matrix? Are suitable capture/detection reagents available? Does endogenous analyte behave similarly to the calibrator?

  • Antibody-pair and epitope strategy
  • Expected endogenous concentration range
  • Calibration material suitability
  • Matrix effect and dilution feasibility
  • Signal-to-background assessment
  • Selectivity and specificity screening
  • Parallelism / dilution-behavior assessment
  • Preliminary precision and stability

Scientific basis: fit-for-purpose biomarker literature emphasizes matching method-development rigor to intended use and evaluating matrix behavior before relying on an assay for study decisions.

Multiplex Bead-Based Immunoassay Feasibility

Key questions: Can all analytes be measured in one sample dilution and matrix without losing meaningful sensitivity or range?

  • Analyte-by-analyte quantitative-range review
  • Minimum required dilution
  • Matrix effect and parallelism
  • Cross-reactivity and cross-talk
  • High/low abundance compatibility
  • QC material and calibrator strategy
  • Reagent lot and vendor continuity
  • Decision whether some analytes belong in singleplex

Scientific basis: multiplex LBA guidance specifically recommends feasibility testing in the intended matrix and recognizes that one assay condition may not be optimal for every analyte in a multiplex.

Flow Cytometry Feasibility

Key questions: Are the cellular populations, surface or intracellular markers, activation states, and functional phenotypes measurable reproducibly in the intended specimen and instrument configuration?

  • Cell population and biological phenotype definition
  • Marker and fluorochrome selection
  • Panel architecture and spectral compatibility
  • Antibody clone and reagent assessment
  • Sample processing, viability, fixation and permeabilization
  • Compensation / unmixing and control strategy
  • Gating strategy and data-analysis reproducibility
  • Rare-event, sensitivity and precision feasibility
  • Instrument configuration and transfer considerations

Scientific basis: MIFlowCyt defines minimum information needed to interpret flow-cytometry experiments, while ICSH/ICCS guidance addresses intended use, specimen and processing conditions, analytical sensitivity/specificity, imprecision, and other performance considerations for cell-based fluorescence assays.

Cell-Based Assay Feasibility

Key questions: Does the cellular model reproduce the biological mechanism of interest, and can the treatment-induced or stimulus-induced response be measured with adequate dynamic range, reproducibility, and biological relevance?

  • Cell line, primary-cell, PBMC or other model selection
  • Cell identity, viability and culture-condition assessment
  • Stimulus, treatment, dose and time-course design
  • Viability, proliferation and cytotoxicity endpoints
  • Apoptosis and cell-death measurements
  • Immune activation and functional-response assays
  • Reporter, signaling or phenotypic endpoints
  • Positive, negative and vehicle control strategy
  • Plate uniformity, signal window and reproducibility
  • Orthogonal confirmation by flow cytometry, qPCR or protein assays when scientifically appropriate

Scientific basis: the NIH/NCATS Assay Guidance Manual includes dedicated guidance for in-vitro cell-based assays, including viability, cytotoxicity, apoptosis, signaling, image-based assays, cellular models, assay artifacts, plate effects, and reproducibility.

Feasibility Design Inputs

Good assay design begins with information. The stronger the inputs, the faster weak concepts can be eliminated and viable approaches can move into formal development.

Biological QuestionWhat mechanism, biomarker, pathway, pathogen, treatment effect, or comparison should the assay interrogate?
Analyte DefinitionExact sequence, isoform, protein form, activation state, antigen, antibody class, or molecular species
Specimen / MatrixTissue, blood, plasma, serum, saliva, urine, swab, FFPE, cell culture, environmental material, or other matrix
Expected AbundanceKnown or estimated concentration, copy number, expression range, prevalence, or biological variability
ComparatorControl vs disease, treated vs untreated, time point, dose, responder group, reference material, or orthogonal method
TechnologyqPCR, RT-qPCR, ELISA, multiplex bead immunoassay, flow cytometry, cell-based assay, or a scientifically justified combination
Critical ReagentsPrimers, probes, antibodies, antigens, standards, calibrators, controls, extraction chemistry, and master mix
Instrument PlatformOptical channels, plate format, reader compatibility, sensitivity, software, throughput, and workflow constraints
ControlsControls mapped to contamination, extraction failure, inhibition, RT failure, matrix interference, calibration, or other risks
Performance NeedQualitative detection, relative change, quantitative range, low-copy sensitivity, precision, or screening-level performance
Sample AvailabilityNumber, type, volume, biological diversity, positive/negative representation, and access to representative materials
Transfer RequirementsFuture laboratory, instrument, operator, reagent format, throughput, manufacturing, or scale-up needs

Feasibility Is Not Full Validation

This distinction is essential. Feasibility generates evidence that a design is worth developing. Validation establishes, with a defined study plan and acceptance criteria, that a method performs adequately for its intended use.

StagePrimary QuestionTypical Evidence
Concept ReviewDoes the proposed analyte and technology make biological sense?Literature, sequence/protein biology, expected abundance, sample availability, known limitations.
FeasibilityCan the concept generate a usable analytical signal in the intended matrix?Prototype data, specificity screen, range/sensitivity estimate, matrix behavior, reagent feasibility, preliminary precision.
OptimizationCan performance be improved and stabilized?Concentration titration, buffer/chemistry changes, cycling or incubation optimization, multiplex balancing, control refinement.
Analytical ValidationDoes the finalized method meet predefined performance requirements?Structured studies of specificity/selectivity, range, precision, sensitivity, robustness, matrix effects, stability, controls, and other intended-use parameters.
Biological VerificationDoes the assay behave meaningfully in representative biological samples?Independent samples, appropriate comparator groups, longitudinal materials, orthogonal measurements, or biological replication.
Technology TransferCan another laboratory or workflow reproduce the method?Transfer protocol, SOP, training, instrument verification, QC materials, predefined comparison criteria.

A Structured Feasibility Study

The NIH Assay Guidance Manual describes assay development and validation as a cycle. IMDNA applies the same principle to research assay feasibility: define the question, identify the major risks, test them efficiently, and use the evidence to determine the next development step.

PhaseFeasibility ActivityDecision Enabled
1. Intended-use definitionClarify analyte, specimen, biological comparison, expected output, and how the data will be used.Prevents development of an assay that technically works but does not answer the research question.
2. Scientific landscape reviewEvaluate published biology, sequence/protein structure, target abundance, known interferences, existing methods, and evidence gaps.Identify high-risk assumptions before reagent spend.
3. Technology selectionChoose molecular, soluble-protein, flow-cytometric, or cell-based functional platform according to the analyte, biological question, and required performance.Avoid forcing an analyte onto an unsuitable technology.
4. Critical reagent assessmentReview primer/probe designability, antibody pairs, standards, controls, reference materials, extraction reagents, and instrument compatibility.Determine whether the basic assay architecture is buildable.
5. Prototype developmentBuild the smallest useful assay capable of testing the critical scientific assumptions.Generate early evidence without over-investing in optimization.
6. Matrix challengeTest representative biological matrix, dilution behavior, inhibition, extraction recovery, nonspecific signal, and stability.Determine whether buffer-only performance translates to real samples.
7. Preliminary performance characterizationEstimate specificity/selectivity, sensitivity, quantitative range, precision, signal-to-background, and robustness parameters relevant to the method.Determine whether the prototype has enough performance margin to justify development.
8. Feasibility decisionSummarize technical risks, evidence, unresolved questions, and recommended path.Go forward, redesign, change matrix, change technology, split multiplex, narrow claims, or stop.

Feasibility Decision Framework

A feasibility study is most useful when it ends with a decision rather than a collection of preliminary experiments.

GOCore biological and analytical assumptions are supported. Advance to structured optimization and analytical validation.
MODIFYThe concept is viable, but target design, reagents, dilution, matrix handling, controls, or assay conditions need redesign.
SPLIT / CHANGE PLATFORMA multiplex should be divided, or the analyte is better measured by a different technology or biological layer.
STOP / REFRAMEThe analyte is not measurable with adequate performance, does not answer the research question, or requires resources disproportionate to the intended use.

Scientifically Responsible Feasibility Interpretation

Early proof-of-concept data are valuable, but they should not be interpreted as evidence of a fully validated method.

  • A detectable signal in buffer does not establish assay performance in the intended biological matrix.
  • A single positive sample does not establish sensitivity, specificity, biological generalizability, or clinical utility.
  • Low background does not establish selectivity if relevant interferents, cross-reactants, homologous targets, or matrix components have not been challenged.
  • Apparent linearity over a small range does not establish a validated quantitative range.
  • A commercial reagent or kit is not automatically fit for a new matrix, population, analyte concentration range, or intended research use.
  • Successful singleplex performance does not establish multiplex feasibility.
  • Feasibility acceptance criteria should be defined according to the research objective and should not be presented as universal diagnostic thresholds.

Why This Matters

Many assay-development failures originate from an incorrect assumption made before optimization: the wrong analyte, wrong specimen, inadequate reagent specificity, unrealistic sensitivity requirement, incompatible multiplex ranges, or an assay format that does not reflect the biology.

Therefore: feasibility is a scientific de-risking stage—not a shortened validation study.

From Assay Concept to Development-Ready Design

A structured feasibility program converts an idea into a technically justified assay-development plan.

Research Question
Analyte Definition
Matrix Assessment
Technology Selection
Prototype Design
Feasibility Testing
Go / Modify Decision
Development Plan

Feasibility Deliverables

The exact package is tailored to the project, but the goal is to leave the feasibility phase with a clear evidence-based path forward.

Scientific Feasibility Summary

Target biology, analyte rationale, intended use, relevant literature, assumptions, and major scientific risks.

Assay Architecture

Recommended technology, target configuration, matrix, workflow, controls, calibration strategy, and instrument requirements.

Critical Reagent Plan

Primer/probe, antibody, antigen, standard, calibrator, control, extraction, buffer, or master-mix requirements.

Proof-of-Concept Data

Prototype assay results addressing the most important technical risks identified at project initiation.

Preliminary Performance Profile

Early estimates of specificity/selectivity, useful range, sensitivity, precision, matrix behavior, or multiplex compatibility as appropriate.

Risk Register

Known limitations, unresolved technical questions, sample constraints, reagent risks, interference risks, and mitigation options.

Go / Modify / Stop Recommendation

A documented feasibility conclusion tied to the intended research use.

Development Plan

Recommended optimization experiments, analytical validation parameters, biological verification strategy, and transfer requirements.

Documentation Package

Project-specific design notes, experimental records, preliminary SOP elements, data summaries, and development recommendations.

Assay Feasibility & Design Services

IMDNA can support feasibility from an early biological concept or enter a project after a preliminary assay has already been attempted. The work can focus on one critical risk or provide a complete pre-development assessment.

Biological target assessment
Literature & sequence review
Analyte / specimen selection
Technology selection
Primer & probe feasibility
Antibody / immunoassay feasibility
Multiplex feasibility assessment
Matrix / interference studies
Control architecture
Proof-of-concept experiments
Preliminary performance studies
Risk assessment & mitigation
Go / modify / stop recommendation
Development & validation roadmap

Why Researchers Work with IMDNA

Biology Before TechnologySelect the platform only after defining what molecular form actually answers the research question.
Multi-Platform PerspectiveCompare qPCR/RT-qPCR, ELISA, multiplex immunoassay, flow cytometry, and cell-based functional approaches instead of forcing every project into one technology.
Early Risk ReductionChallenge the highest-risk assumptions before full optimization, validation, or scale-up.
Fit-for-Purpose DesignMatch analytical rigor to how the research data will actually be used.
Development ContinuityMove successful feasibility programs directly into assay optimization, analytical validation, reagent configuration, and technology transfer.

Scientific Foundation & Authoritative / Methodological References

  1. NIH / NCATS — Assay Guidance Manual. The Assay Guidance Manual is a continuously maintained NIH/NCATS resource for scientists developing robust biological assays. It addresses assay-format selection, reagents, sensitivity, dynamic range, signal stability, artifacts and interference, instrumentation, optimization, statistical performance, validation, and assay transfer. Its central principle is that an assay should be demonstrated to be acceptable for its intended purpose.
    NCBI Bookshelf — Assay Guidance Manual
    PubMed record
  2. Bustin SA, Ruijter JM, van den Hoff MJB, et al. — MIQE 2.0. MIQE 2.0: Revision of the Minimum Information for Publication of Quantitative Real-Time PCR Experiments Guidelines. Clinical Chemistry. 2025;71(6):634–651. Provides the current framework for qPCR/RT-qPCR sample handling, assay design, specificity, efficiency, controls, normalization, dynamic range, detection/quantification limits, analysis, and reporting.
    Clinical Chemistry — MIQE 2.0
  3. ISO 20395:2019. Biotechnology — Requirements for evaluating the performance of quantification methods for nucleic acid target sequences — qPCR and dPCR. ISO 20395 provides generic requirements for nucleic-acid quantification method performance, including PCR assay design, in-silico/in-vitro specificity, controls, precision, linearity, detection and quantification limits, trueness, robustness, normalization, traceability, and measurement uncertainty. The 2019 edition remains the published standard while a revision is in development.
    Official ISO 20395:2019 page
  4. Lee JW, Devanarayan V, Barrett YC, et al. Fit-for-purpose method development and validation for successful biomarker measurement. Pharmaceutical Research. 2006;23(2):312–328. This influential biomarker-method paper proposes an iterative fit-for-purpose approach in which the degree of method development and validation is matched to the intended use of the data.
    PubMed publication
  5. Jani D, Allinson J, Berisha F, et al. Recommendations for Use and Fit-for-Purpose Validation of Biomarker Multiplex Ligand Binding Assays in Drug Development. AAPS Journal. 2016;18(1):1–14. The paper specifically recommends feasibility evaluation of multiplex assays in the intended matrix and discusses quantitative range, sensitivity, minimum required dilution, cross-talk, matrix effects, parallelism, stability, reagent lots, and analyte-specific compromises.
    PubMed publication
  6. Tu J, Bennett P. Parallelism experiments to evaluate matrix effects, selectivity and sensitivity in ligand-binding assay method development: pros and cons. Bioanalysis. 2017;9(14):1107–1122. Supports use of dilutional parallelism during endogenous ligand-binding assay development to investigate matrix effects, selectivity, minimum required dilution, endogenous concentrations, and effective sensitivity.
    PubMed publication
  7. FDA / ICH M10 — Bioanalytical Method Validation and Study Sample Analysis. M10 states that the purpose of bioanalytical validation is to demonstrate that a method is suitable for its intended purpose and provides detailed recommendations for regulated drug bioanalysis. Its principles are informative for understanding analytical validation, but an RUO feasibility study should not be represented as M10 validation unless the method and study are actually developed within the applicable regulated context.
    FDA / ICH M10 guidance
  8. Lee JA, Spidlen J, Boyce K, et al. — MIFlowCyt. MIFlowCyt: the minimum information about a Flow Cytometry Experiment. Cytometry Part A. 2008;73(10):926–930. Establishes minimum reporting information for specimens, reagents, instrument configuration, and data processing so flow-cytometry experiments can be interpreted and reproduced.
    PubMed publication
  9. Wood B, Jevremovic D, Béné MC, et al.; ICSH/ICCS Working Group. Validation of cell-based fluorescence assays: practice guidelines from the ICSH and ICCS — Part V: assay performance criteria. Cytometry B Clinical Cytometry. 2013;84(5):315–323. Discusses validation strategies and performance criteria for qualitative and quasi-quantitative cell-based flow-cytometric assays, including imprecision, sensitivity, and specificity.
    PubMed publication
  10. NIH / NCATS Assay Guidance Manual — In Vitro Cell Based Assays. This dedicated section covers cell viability, cytotoxicity, apoptosis, cellular signaling, high-content and image-based assays, primary and iPSC-derived cellular models, and other cell-based assay-development approaches relevant to feasibility and proof-of-concept work.
    NCBI Bookshelf — In Vitro Cell Based Assays
Scope of these references: The NIH/NCATS Assay Guidance Manual supports the general assay-development, feasibility, optimization, artifact/interference, validation, and transfer framework. MIQE 2.0 and ISO 20395 support qPCR/RT-qPCR analytical design and performance concepts. Lee et al., Jani et al., and Tu & Bennett support fit-for-purpose biomarker, ELISA/ligand-binding, matrix, parallelism, and multiplex feasibility concepts. MIFlowCyt and ICSH/ICCS guidance support flow-cytometry experimental documentation and cell-based fluorescence assay performance concepts. The NIH/NCATS cell-based assay resources support design of functional cellular assays, viability/cytotoxicity endpoints, signaling assays, and reproducibility considerations. ICH M10 is included only as a regulated bioanalytical reference and is not presented as the governing standard for IMDNA RUO feasibility studies. These sources do not imply endorsement of IMDNA and do not establish any IMDNA assay as diagnostic, prognostic, predictive, or clinically validated.

Determine Whether Your Assay Concept Is Ready for Development

Whether your project begins with a biomarker hypothesis, pathogen target, gene-expression signature, mutation, fusion transcript, cytokine panel, protein biomarker, new sample type, multiplex concept, or partially developed assay, IMDNA can evaluate the scientific and analytical feasibility and define a practical development path around the intended research use.

Discuss Your Assay Feasibility & Design Project with IMDNA
For Research Use Only (RUO). Not for use in diagnostic procedures. Feasibility studies are exploratory/pre-development activities and do not by themselves establish analytical validation, clinical performance, or regulatory suitability.