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Custom RNA Imaging Probes

Custom RNA imaging probes for transcript localization, single-molecule detection, live-cell imaging, multiplex RNA visualization and spatial biology research. Bio-Synthesis manufactures fluorescently labeled RNA probes, molecular beacons, smFISH probe sets, barcoded imaging probes and custom RNA visualization oligonucleotides.

RNA Localization Fluorescent Probes Molecular Beacons Spatial Biology

What Are RNA Imaging Probes?

RNA imaging probes are oligonucleotide-based detection reagents designed to visualize RNA molecules within cells, tissues, organoids and biological samples.

Unlike conventional RNA sequencing methods that measure transcript abundance after extraction, RNA imaging techniques preserve spatial information and reveal where transcripts are located within their native biological environment.

RNA imaging probes can be used for single-transcript detection, RNA localization studies, multiplex gene-expression analysis, live-cell RNA tracking and spatial transcriptomics workflows. Depending on the application, probe architectures may incorporate fluorescent dyes, molecular beacons, barcode sequences, amplification domains, quencher systems or specialized chemical modifications.

Bio-Synthesis manufactures custom RNA imaging probes with fluorescent labeling, barcode integration, probe pools, conjugation chemistry and custom oligonucleotide design support.

FL

Fluorescent Signal

Probe hybridization creates visible fluorescent signal for transcript localization and imaging.

RNA

Targeted Detection

Custom sequences hybridize to specific RNA targets, isoforms or transcript panels.

Mx

Multiplex Ready

Barcoded and readout-based architectures support multiplex RNA visualization.

RNA Probe Animation: Single-Strand Probe Entry → Target RNA Binding → Fluorescence
target RNA inside cellsingle-strand probe enteringfluorescent bound probe

RNA Imaging Technology Options

RNA imaging is broader than spatial transcriptomics. It includes direct RNA FISH, smFISH, molecular beacons, MERFISH, seqFISH and custom barcoded imaging workflows.

Select an RNA imaging technology

smFISH — multiple fluorescent probes bind one transcript to visualize single RNA molecules.

RNA localization
low-medium
direct fluorescence

Advantages

High sensitivity, direct detection and strong transcript localization.

Best Fit

Single-gene validation, RNA localization and mechanistic imaging studies.

Probe Format

Multiple fluorescent oligos tiled along one RNA transcript.

Molecular Beacons — stem-loop probes that fluoresce when opened by target binding.

signal-on detection
dye + quencher
fluorescence ON

Advantages

Low background, target-triggered signal and high specificity.

Best Fit

Dynamic RNA monitoring, live-cell studies and signal-on hybridization assays.

Probe Format

Hairpin probe with fluorophore and quencher that separates upon target binding.

MERFISH — barcoded RNA imaging with encoding and readout probe sets.

high multiplex
encoding + readout
spatial transcriptomics

Advantages

Very high multiplexing, error-robust barcodes and spatial gene-expression mapping.

Best Fit

Cell atlas studies, tumor microenvironment mapping and large gene panels.

Probe Format

Encoding probes carry barcode readout sequences decoded through imaging rounds.

seqFISH — sequential hybridization cycles identify RNA targets through combinatorial readout.

sequential panels
readout cycles
spatial expression

Advantages

High multiplex capacity and flexible panel design.

Best Fit

Spatial gene-expression profiling and multiplex RNA imaging.

Probe Format

Sequential readout probes produce transcript-specific fluorescence patterns.

RNA Imaging Probe Formats

Probe architecture can be simple or highly engineered depending on whether the goal is direct detection, signal-on hybridization, multiplex barcoding or amplified readout.

Select a probe format

Direct Fluorescent Probes — terminal or internal dyes produce signal after hybridization.

FAM / Cy / Alexa / ATTO
RNA FISH
low-medium
brightness

Common Dyes

FAM, HEX, TAMRA, ROX, Cy3, Cy5, Alexa Fluor, ATTO and NIR dye options.

Label Position

5′, 3′ or internal dye placement can be considered depending on design.

Applications

RNA FISH, smFISH, localization studies and fluorescent readout probes.

Molecular Beacon Format — probe is dark when closed and fluorescent when target-bound.

dye + quencher
signal-on
low background
stem + loop

Quenchers

BHQ, Dabcyl, Iowa Black and other dark quenchers can be evaluated.

Stem-Loop Design

Stem stability and target-binding loop determine background and signal response.

Applications

RNA detection, live-cell studies and real-time hybridization monitoring.

Barcoded RNA Imaging Probes — add barcode and readout domains for multiplex imaging.

MERFISH / seqFISH
encoding + readout
orthogonality
cross-readout

Readout Domains

Secondary probes bind barcode sequences during imaging cycles.

Encoding Probes

Target-binding probes carry transcript identity information.

Applications

Spatial transcriptomics, high-plex RNA imaging and custom gene panels.

Amplified Imaging Probes — probe systems designed for stronger signal or low-abundance transcripts.

low abundance
amplification domains
sensitivity
background

Amplification Elements

Architecture can include handles or domains that support signal amplification systems.

Low-Abundance Targets

Probe density, readout strategy and amplification may improve visibility.

Controls

Background controls and specificity checks are important for amplified systems.

RNA Imaging Probe Modifications Bio-Synthesis Can Support

Bio-Synthesis supports a wide range of fluorescent dyes, quenchers, haptens, spacers, conjugation handles and custom modified oligonucleotide designs for RNA imaging workflows.

Fluorescent Dyes

FAM, HEX, TET, TAMRA, ROX, Cy3, Cy5, Cy5.5, Cy7, Alexa Fluor, ATTO, NIR and specialty imaging dyes.

Quenchers

BHQ-1, BHQ-2, BHQ-3, Iowa Black, Dabcyl and custom quencher strategies for beacon probes.

Haptens & Handles

Biotin, DIG, DNP, amino, thiol, azide, alkyne and other conjugation handles.

Internal Labels & Spacers

Internal amino-dT, internal fluorophores, PEG spacers, HEG, TEG and flexible linker options.

Modification Class Examples Typical RNA Imaging Use
Fluorophores FAM, Cy3, Cy5, Alexa Fluor, ATTO, NIR dyes Direct RNA imaging, smFISH, readout probes, multiplex panels.
Quenchers BHQ, Dabcyl, Iowa Black Molecular beacons and signal-on RNA detection probes.
Haptens Biotin, DIG, DNP Indirect detection and signal amplification strategies.
Conjugation Handles Amino, thiol, azide, alkyne Custom dye attachment, surface coupling and specialized reagent development.
Spacers TEG, HEG, Spacer 9, Spacer 18 Reduce steric hindrance and improve readout accessibility.
Affinity / Stability 2′-OMe, 2′-F, LNA/BNA/ENA, PS Specialized designs requiring enhanced binding or nuclease resistance.

Need a dye not listed? Review the full fluorescent labeling options here: Fluorescent-Labeled Oligonucleotides.

Applications for RNA Imaging Probes

Loc

RNA Localization

Map transcript location within cells, tissues, organoids or subcellular compartments.

Live

Live-Cell Imaging

Use signal-on or specialized probe formats for dynamic RNA monitoring workflows.

Neuro

Neuroscience

Visualize neuronal transcripts, cell-type markers and region-specific RNA patterns.

Onc

Oncology

Study tumor biomarkers, microenvironment patterns and spatial RNA signatures.

ST

Spatial Transcriptomics

Support MERFISH, seqFISH and other barcoded spatial RNA imaging workflows.

Bio

Biomarker Validation

Validate RNA-seq or single-cell findings using targeted fluorescent RNA probes.

RNA Imaging Probe Design Considerations

RNA imaging probe performance depends on target accessibility, fluorophore selection, signal-to-background ratio, multiplex design and sample type.

Select a design topic

Fluorophore Selection — match dye brightness, excitation and emission to the imaging platform.

FAM / Cy / Alexa / ATTO
brightness
bleed-through
label confirmation

Channel Planning

Choose dyes around laser lines, filter sets, detector sensitivity and autofluorescence.

Dye Stability

Consider photostability for long imaging sessions or repeated imaging cycles.

Label Position

Terminal or internal dye placement should be matched to probe architecture.

Signal-to-Background Optimization — reduce nonspecific signal and improve contrast.

quenchers
no-probe / mismatch
autofluorescence
contrast

Probe Specificity

Sequence design and hybridization conditions affect background signal.

Quencher Systems

Molecular beacons use dye/quencher proximity to stay dark until target binding.

Controls

No-probe, scrambled, mismatch and positive-control probes help evaluate specificity.

Multiplex Strategy — plan barcodes, readouts and fluorescent channels before synthesis.

MERFISH / seqFISH
barcodes
cross-talk
orthogonality

Barcode Domains

Readout sequences should be orthogonal and compatible across imaging cycles.

Spectral Panel

Minimize bleed-through between fluorophores and readout channels.

Panel Complexity

Larger panels require careful design review and sequence management.

Sample Type — probe design should account for RNA accessibility and preparation conditions.

cells / tissue / FFPE
RNA quality
accessibility
controls

Fixed Cells

Often suitable for smFISH, RNA localization and targeted imaging.

Tissue Sections

May require attention to penetration, background and autofluorescence.

FFPE

RNA fragmentation and fixation effects can influence probe design and target choice.

Custom RNA Imaging Probe Workflow

01

Target Selection

Define transcript, isoform, marker panel or pathway genes.

02

Probe Architecture

Select smFISH, beacon, barcode, readout or amplification strategy.

03

Labeling Strategy

Choose fluorophores, quenchers, haptens, spacers or handles.

04

Synthesis

Manufacture custom oligos, probe pools or labeled probe sets.

05

QC

Support analytical testing, concentration, documentation and custom packaging.

06

Imaging Use

Apply probes in RNA FISH, live-cell, spatial or multiplex imaging workflows.

FAQ

Can Bio-Synthesis manufacture custom barcoded RNA imaging probes?
Yes. Bio-Synthesis supports barcoded probe designs, readout domains, encoding probes and custom oligonucleotide architectures for multiplex RNA imaging workflows.
Can probes include quenchers or internal labels?
Yes. Options may include quenchers, internal fluorophores, amino-dT, haptens, spacers and other custom modifications depending on design and feasibility.
What probe chemistry is best for multiplex imaging?
Multiplex imaging typically requires careful fluorophore selection, orthogonal barcode/readout design, low cross-reactivity and channel compatibility. Bio-Synthesis can help evaluate dye, barcode and modification options.
Can RNA imaging probes be used in live cells?
Some probe formats, such as molecular beacons or specialized signal-on probes, may be suitable for live-cell RNA monitoring depending on delivery, stability, target accessibility and experimental conditions.
Which fluorescent dyes are available?
Bio-Synthesis supports a wide range of fluorophores including FAM, HEX, TET, TAMRA, ROX, Cy dyes, Alexa Fluor dyes, ATTO dyes, NIR dyes and specialty imaging fluorophores.
What is the difference between RNA imaging and spatial transcriptomics?
RNA imaging is a broad category that includes RNA localization, smFISH, molecular beacons, live-cell imaging and multiplex RNA visualization. Spatial transcriptomics is a subset focused on spatially resolved gene-expression profiling.
What is the difference between smFISH and molecular beacons?
smFISH typically uses multiple fluorescent probes that directly bind one RNA transcript, while molecular beacons are stem-loop probes that fluoresce only when opened by target binding.
What are RNA imaging probes?
 RNA imaging probes are oligonucleotide-based reagents designed to visualize RNA molecules in cells, tissues, organoids or biological samples while preserving spatial information.

Information Helpful for an RNA Imaging Probe Quote

Target
gene, isoform, transcript
Format
smFISH, beacon, barcode
Dyes
FAM, Cy, Alexa, ATTO
Modifications
quencher, spacer, hapten
Sample
cells, tissue, FFPE
QC
HPLC, MS, CoA

Need help designing fluorescent RNA imaging probes?

Share your RNA target, species, probe format, fluorescent dye preferences, quencher or modification requirements, sample type, imaging platform, scale, purification and QC needs. Bio-Synthesis can help translate your RNA imaging goal into a manufacturable oligonucleotide probe strategy.
FL

Fluorescent Labels

Broad dye portfolio, NIR dyes, internal labels and multiplex-compatible readout probes.

FAM Cy5 Alexa
RNA

Probe Architecture

smFISH, molecular beacons, barcoded probes, readout probes and custom RNA imaging formats.

smFISH Beacon MERFISH

Quality Systems & Manufacturing Support

RNA imaging probe programs require controlled synthesis, labeling, purification, analytical QC, sequence handling and delivery documentation.

QMS

ISO-Supported Oligonucleotide Manufacturing Platform

Bio-Synthesis supports custom RNA imaging probes, fluorescent labels, quenchers, barcoded probe pools, conjugation chemistry, purification, analytical QC, documentation and project-specific packaging.

ISO 9001:2015 Quality management system
ISO 13485:2016 Medical-device quality framework
Analytical QC HPLC/UPLC, MS where compatible, OD260, CoA and traces
Custom Programs RNA FISH, smFISH, molecular beacon, MERFISH and seqFISH support

RNA Imaging Literature & Technical Background

  1. Raj A, van den Bogaard P, Rifkin SA, van Oudenaarden A, Tyagi S. Imaging individual mRNA molecules using multiple singly labeled probes. Nature Methods. 2008.
  2. Tyagi S, Kramer FR. Molecular beacons: probes that fluoresce upon hybridization. Nature Biotechnology. 1996.
  3. Femino AM, Fay FS, Fogarty K, Singer RH. Visualization of single RNA transcripts in situ. Science. 1998.
  4. Chen KH, Boettiger AN, Moffitt JR, Wang S, Zhuang X. Spatially resolved, highly multiplexed RNA profiling in single cells. Science. 2015.
  5. Eng CL, Lawson M, Zhu Q, et al. Transcriptome-scale super-resolved imaging in tissues by RNA seqFISH+. Nature. 2019.
  6. Crosetto N, Bienko M, van Oudenaarden A. Spatially resolved transcriptomics and beyond. Nature Reviews Genetics. 2015.

Technical note: Final RNA imaging probe design should be evaluated within the target transcript, sample preparation, imaging platform, dye channels, probe architecture and experimental objective.

Why Choose Bio-Synthesis

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