custom miRNA mimic synthesis • custom antagomir synthesis • anti‑miR inhibitor CDMO

Custom miRNA Mimic & Antagomir (anti‑miR) Synthesis Services

High‑performance custom miRNA mimic (agomir) and anti-miR synthesis with LNA, 2′ modifications, PS backbones, conjugation, labeling, purification, and LC-MS QC from discovery to preclinical.

Agomir duplex + strand bias support anti‑miR: PS + 2′ + LNA options Conjugations: cholesterol / GalNAc / PEG Labels: FAM/Cy dyes • biotin

Overview

MicroRNAs (miRNAs) are ~22-nt regulatory RNAs that direct the RNA-induced silencing complex (RISC) to partially complementary target sequences, resulting in translational repression and mRNA destabilization1,2. Synthetic miRNA tools enable precise modulation of gene networks: miRNA mimics (agomirs) restore or amplify endogenous miRNA function (gain-of-function), while antagomirs (anti‑miRs) selectively inhibit native miRNAs to induce controlled loss-of-function effects.

Because these modalities operate through distinct mechanistic pathways, their engineering strategies differ fundamentally. Mimics are optimized to promote efficient guide strand Ago loading while minimizing passenger strand activity to ensure accurate RISC engagement. In contrast, anti‑miRs are engineered for high binding affinity, nuclease resistance, and functional durability to effectively compete with abundant, protein-associated miRNAs in complex biological systems.

At Bio-Synthesis, we serve as a technical partner for high-performance custom miRNA mimic (agomir) duplex synthesis and antagomir / anti‑miR inhibitor manufacturing. Our platform supports advanced chemistries including LNA, 2′-O-Me, 2′-F, 2′-MOE, and phosphorothioate (PS) backbone configurations, along with delivery-focused conjugations (cholesterol, GalNAc, PEG) and labeling options (FAM/Cy dyes, biotin). Integrated purification strategies and analytical validation (HPLC, LC-MS, COA) enable seamless progression from discovery through preclinical development.

At a glance
Agomir
Duplex mimic

Guide loading + passenger suppression

Antagomir
Inhibitor

High affinity • nuclease resistance

Chemistry
2′ + LNA + PS

Stability, affinity, immune profile

QC
Orthogonal

HPLC + LC‑MS + COA

Deliverables

RNase‑free lyophilized oligos (or solution), optional duplex annealing, and documentation (COA + chromatography + MS) aligned to program stage.

Related RNA therapeutics CDMO platforms

For duplex RNA modalities, see siRNA manufacturing. For antisense programs, explore ASO manufacturing. For delivery strategies, see receptor‑targeted oligonucleotide conjugation and oligo‑lipid conjugation.

Typical miRNA Use Cases

GainRescue
Replacement biology

Restore a downregulated miRNA and observe target repression and phenotype rescue.

LossValidate
Inhibition studies

Block an oncomiR or pathway‑driving miRNA to de‑repress targets and test causality.

ScreenDose
Phenotypic screening

Dose‑response and kinetics profiling across chemistries for robust, interpretable hits.

In vivoDelivery
Preclinical POC

Stabilized anti‑miRs with conjugation/formulation for tissue‑directed inhibition.

How miRNA Mimics and Antagomirs Work

Mimics (agomirs) aim to reproduce native miRNA loading and targeting, while inhibitors (antagomirs/anti‑miRs) bind the mature miRNA and block function. Chemistry and positional choices tune the balance between potency, specificity, durability, and developability.

1Deliver
Cellular entry

Transfection, nanoparticles, or conjugation‑enabled uptake (design‑dependent).

2Engage
Target engagement

Mimic: Ago loading of guide strand. anti‑miR: antisense binding to mature miRNA.

3Shift
Functional outcome

Mimic: target repression. anti‑miR: de‑repression (loss of miRNA activity).

Diagram: How miRNA Mimics & Antagomirs Work
How miRNA mimics (agomirs) and antagomirs (anti‑miR inhibitors) work: mimic duplex loads into RISC for target repression; antagomir binds endogenous miRNA to block activity and de-repress targets.
Mechanism clarity
For mimics, strand bias and passenger suppression drive interpretability. For anti‑miRs, affinity and nuclease resistance are the dominant constraints, then delivery choices tune exposure and durability.

Agomir vs Antagomir: Design Strategy Comparison

Use this table as a practical decision guide when selecting format, chemistry depth, and controls.

Dimension miRNA Mimic (Agomir) Antagomir (anti‑miR)
Format Duplex (guide + passenger) Single‑stranded antisense
Biology Gain‑of‑function (restore/enhance miRNA activity) Loss‑of‑function (inhibit endogenous miRNA)
Primary constraint Ago loading + strand selection; passenger suppression High affinity vs abundant miRISC; nuclease resistance
Typical chemistry Selective 2′ mods (often passenger/ends), optional limited PS; optional 5′ phosphate PS backbone, 2′‑OMe/2′‑F/2′‑MOE, LNA blocks, end protection
Common artifacts Passenger off‑targets; seed‑driven off‑targets at high doses Non‑specific protein binding (high PS); delivery‑driven toxicity/confounds
Best for Replacement biology, pathway activation Target validation, durable inhibition, in vivo proof‑of‑concept

Custom miRNA Mimic & anti‑miR Synthesis Services

We manufacture custom miRNA mimic oligonucleotides with flexible chemistry patterns and scalable production workflows.

MimicDuplex
Custom miRNA mimic duplex synthesis

Agomir duplex design support (strand bias, passenger suppression), optional duplex annealing and verification.

Inhibitoranti‑miR
Custom antagomir / anti‑miR inhibitor synthesis

High‑affinity inhibitor builds including LNA anti‑miR synthesis, 2′ chemistries, and end protection.

BackbonePS
Phosphorothioate (PS) antagomir manufacturing

PO/PS mixing strategies to balance stability, affinity, exposure, and specificity (program‑dependent).

ConjugationDelivery
Conjugated anti‑miR synthesis

Cholesterol‑conjugated antagomirs and GalNAc‑anti‑miRs for tissue‑strategy workflows; PEG and lipid variants on request.

LabelsAssays
Fluorescent labeled miRNA mimics & inhibitors

FAM/Cy3/Cy5 and biotin options for uptake tracking, imaging, and pull‑down assays.

QCCOA
Purification + analytical validation

HPLC/PAGE options, LC‑MS confirmation (as applicable), OD260, and documentation packages (COA + traces).

Fast feasibility review (recommended)

Send the miRNA ID/species, format (mimic vs anti‑miR), in vitro vs in vivo intent, preferred chemistry (LNA/2′/PS), conjugation/label needs, purification level, QC package, and target scale.

Common Chemical Modifications

Chemical optimization is central to stability, affinity, specificity, immune profile, and delivery compatibility. Mimics often use selective patterns to preserve Ago loading; anti‑miRs often use heavier stabilization for potency and durability.

Engineering layer Examples supported What it enables Notes
Sugar (2′) modifications 2′‑O‑Me, 2′‑F, 2′‑O‑MOE, LNA Affinity tuning, nuclease resistance, immune profile tuning LNA commonly used in anti‑miRs for steep affinity gains; patterning matters
Backbone linkages PS, mixed PO/PS Serum stability, exposure tuning via protein binding Balance PS content vs specificity; program‑dependent optimization
End protection Terminal caps, inverted bases (e.g., inverted dT), blocking groups Reduced exonuclease degradation Common in inhibitor designs
Conjugations Cholesterol, GalNAc, PEG, lipid variants Distribution, uptake, exposure and durability tuning Choose with route and tissue strategy
Labels FAM, Cy3, Cy5, biotin, quencher pairs Uptake tracking, imaging, pull‑down assays Available on mimics or inhibitors (design‑dependent)
Common high‑performance anti‑miR pattern (illustrative)

Many in vivo inhibitor workflows emphasize PS backbone + 2′ chemistries and/or LNA blocks, then tune distribution with conjugation or formulation. The optimal pattern is tissue/route‑dependent.

Design add‑ons
Chemistry screens • positional patterns • control sets • label/conjugation selection

Preclinical Manufacturing & Documentation (CDMO‑Style)

We execute miRNA programs with CDMO-level chemistry control, scalable manufacturing workflows, and documentation aligned to progression from discovery through preclinical development.

ScaleRepro
Scalable production

Synthesis and purification workflows that can transition from mg to larger preclinical quantities (program‑dependent).

DocsTrace
Documentation packs

COA, analytical traces, and batch summaries; additional documentation can be aligned to your development stage.

RiskControl
Stage‑aligned QC

Orthogonal analytics and optional tests (endotoxin/bioburden, stability) selected based on route, model, and regulatory pathway intent.

Manufacturing, Purification & Analytical Validation

miRNA tools introduce chemistry‑ and format‑driven CQAs such as duplex integrity (mimics), modification completeness, and close‑running impurity profiles. Our workflow supports program progression with scalable execution and documentation.

PurificationResolve
Purity strategy

Desalt / cartridge / HPLC / PAGE options aligned to length, chemistry, and downstream use.

AnalyticsConfirm
Orthogonal confirmation

HPLC purity profiling + LC‑MS identity confirmation (as applicable), plus OD260 quantitation.

DuplexOption
Mimic annealing

Optional duplex annealing and confirmation support for miRNA mimics (design‑dependent).

Typical deliverables

COA (as applicable), chromatography traces, MS spectra/confirmation (as applicable), and batch summary aligned to project stage. Optional testing can be added based on requirements (e.g., endotoxin/bioburden, stability assessments).

Experimental Applications

miRNA mimics and inhibitors are used across functional biology, target validation, pathway modulation, and preclinical proof‑of‑concept—especially when paired with controls and orthogonal readouts.

DiscoveryMoA
Functional validation

Gain/loss perturbations, reporter assays, pathway readouts, and target confirmation.

ScreenDose
Phenotypic screening

Chemistry panels and dose‑response sets to prioritize robust, interpretable phenotypes.

In vivoPOC
Preclinical inhibition

Stabilized anti‑miRs with conjugation/formulation to tune exposure and durability.

Controls that improve interpretability

Scrambled negative controls, seed‑mutant controls, passenger controls (mimics), multiple independent designs, and dose‑ranging help separate on‑target miRNA biology from chemistry‑ or delivery‑driven artifacts.

Ultra‑Technical Brief: Designing miRNA Tools That Scale

The highest‑impact technical levers are: (i) Ago loading and strand selection (mimics), (ii) seed‑driven specificity and off‑target control, and (iii) affinity + exposure constraints for anti‑miRs. Use this section as a checklist for building robust, scale‑aligned designs.

1) Strand bias & passenger suppression (mimics

Engineer duplex asymmetry to favor guide loading, and suppress passenger activity with mismatches and/or heavier passenger modifications. Over‑stabilizing the guide can reduce productive Ago loading—optimize the minimum chemistry needed for stability and performance.

2) Seed specificity (nt 2–8) dominates target spectrum

Seed pairing drives much of the regulatory network. Use seed‑mutant controls and multiple independent designs, and consider transcriptome‑level validation (RNA‑seq + motif enrichment) when phenotypes are complex or surprising.

3) anti‑miR potency is often affinity‑limited

anti‑miRs must compete with abundant, protein‑associated miRNAs. LNA blocks and 2′ chemistry patterns increase affinity; PS content increases stability and exposure, but excessive PS can increase non‑specific binding. Optimize affinity first, then tune distribution/durability via backbone/conjugation/formulation.

4) Kinetics matter

Sampling windows can shift with chemistry and delivery. Profile early vs late timepoints, and use dose‑response series rather than single‑dose conclusions. Plan for durability when interpreting in vivo inhibitor effects.

Recommended validation checklist

Uptake confirmation • dose‑response • on‑target engagement (reporter + endogenous targets) • independent designs • robust controls.

FAQ

What is the difference between antagomir and anti‑miR?

They are often used interchangeably. “Antagomir” frequently implies a heavily stabilized inhibitor (e.g., PS + 2′ chemistry ± LNA and sometimes a conjugation) intended for durable inhibition.

Do you offer custom miRNA mimic synthesis (agomir duplexes)?

Yes. We provide custom miRNA mimic duplex synthesis with options for strand bias engineering, passenger suppression, optional duplex annealing, and purification/QC aligned to your study stage.

Do you provide LNA anti‑miR synthesis?

Yes. We support LNA‑modified anti‑miR inhibitor synthesis (positional block patterns on request) and can combine LNA with 2′ chemistries and PS backbone strategies for potency and durability.

Can you synthesize phosphorothioate (PS) antagomirs?

Yes. We manufacture PS antagomirs and mixed PO/PS designs to tune stability/exposure while managing specificity (program‑dependent optimization).

Do you offer cholesterol‑conjugated antagomirs or GalNAc anti‑miRs?

Yes. We support cholesterol‑conjugated antagomirs and GalNAc‑anti‑miR synthesis (design‑ and route‑dependent). We can also discuss PEG or lipid variants depending on delivery strategy.

Which 2′ modifications do you support for miRNA mimics and inhibitors?

Common options include 2′‑O‑Me2′‑F, and 2′‑O‑MOE. Mimics often use selective patterns to preserve Ago loading; inhibitors often use heavier stabilization for affinity and durability.

What information do you need for a quote?

miRNA ID/species, format (mimic vs inhibitor), intended use (in vitro/in vivo), desired chemistries (LNA/2′/PS), conjugations/labels, purification, QC package, and target scale.

What purification is recommended for custom miRNA oligos?

For reproducibility, HPLC is commonly chosen. PAGE can be used for demanding separations. Early screening may use simpler purification depending on goals and budget.

What QC and analytics are included?

Typical QC includes HPLC purity profiling, LC‑MS identity confirmation (as applicable), and OD260 quantitation with COA. Optional testing (e.g., endotoxin/bioburden, duplex verification, stability) can be added by stage.

How do I reduce off‑target effects in miRNA mimic experiments?

Use dose‑response, seed‑mutant controls, and independent designs. For mimics, suppress passenger loading via sequence/chemistry. Consider transcriptome‑level validation when phenotypes are complex.

Talk to a Scientist

Share your target miRNA and intended use (mimic vs inhibitor), chemistry preferences (2′/LNA/PS), any conjugation/label needs, purification level, QC/documentation requirements, and scale target. We’ll align design, synthesis, purification, and analytics to your stage.

Client‑designed sequences Confidential inputs Chemistry & pattern screens Scale‑aligned execution
What to include in your request
  • Target miRNA (ID + species) and format (agomir vs anti‑miR)
  • Chemistry pattern intent (2′‑OMe/2′‑F/2′‑MOE/LNA, PS level)
  • Conjugation/labels (cholesterol, GalNAc, PEG, FAM/Cy, biotin)
  • Purification (HPLC/PAGE) + QC package (HPLC/LC‑MS/OD260, COA)

Recommended Reading

Selected publications relevant to folate receptor targeting, ligand conjugation, and oligonucleotide delivery chemistry.

  1. Bartel DP. MicroRNAs: genomics, biogenesis, mechanism, and function. Cell. 2004;116(2):281–297.
  2. Jonas S, Izaurralde E. Towards a molecular understanding of microRNA-mediated gene silencing. Nat Rev Genet. 2015;16:421–433.
  3. Ha M, Kim VN. Regulation of microRNA biogenesis. Nat Rev Mol Cell Biol. 2014;15:509–524.
  4. Krützfeldt J et al. Silencing of microRNAs in vivo with ‘antagomirs’. Nature. 2005;438:685–689.
  5. van Rooij E, Kauppinen S. Development of microRNA therapeutics. EMBO Mol Med. 2014;6:851–864.
  6. Rupaimoole R, Slack FJ. MicroRNA therapeutics: towards a new era for the management of cancer. Nat Rev Drug Discov. 2017;16:203–222.

Why Choose Bio-Synthesis

Trusted by biotech leaders worldwide for over 45+ years of delivering high quality, fast and scalable synthetic biology solutions.