January 08, 2026 – [New Castle, Delaware] Lab Bioreagents announces the upcoming launch of its aptamer-based platform designed to expand binding reagent options for biomarker assay development. The platform leverages SELEX (Systematic Evolution of Ligands by Exponential Enrichment) technology to identify high-affinity nucleic acid aptamer for biomarker targets.

Antibodies have long been used as detection reagents in biomarker assays; however, for a subset of biomarkers, generating high-quality antibodies remains challenging or impractical due to low immunogenicity, small molecular size, high sequence conservation, or pronounced structural flexibility. As a result, antibodies developed for these targets often exhibit low affinity or cross-reactivity, leading to reduced assay sensitivity and specificity.

Aptamers—short, single-stranded nucleic acids first introduced in the early 1990s—offer an alternative approach. Produced entirely in vitro, aptamers fold into defined three-dimensional structures and recognize target molecules through hydrogen bonding and structural complementarity. Unlike antibodies, aptamer selection does not rely on immune responses, enabling access to targets that are traditionally challenging for antibody development.


1.      Will aptamers fit all biomarker assays?

No. Aptamers are not universal replacements for antibodies. They are superior to anti-ID antibodies in specific scenarios, including:

a)      Non-immunogenic or weakly immunogenic biomarkers, where antibody generation is inefficient

b)     Small molecules or small proteins with limited binding surfaces

c)      Conformation-specific measurements, such as detecting pathological protein states while sparing normal forms

2.      Are aptamers stable in bioassays, especially in blood matrices?

Yes, when properly designed.

a)       Typical biomarker assays run 4–8 hours, during which aptamers are generally stable.

b)       Aptamers are highly stable in CSF-based assays and in diluted blood matrices (minimum required dilution ≥3).

c)       Chemical modifications such as 2′-O-methyl or 2′-fluoro substitutions on pyrimidines can significantly enhance nuclease resistance, making aptamers stable across a wide range of biological matrices.

3.      Which bioanalytical platforms are compatible with aptamers?

Aptamers are highly versatile and compatible with multiple detection platforms:

    Biotin-conjugated aptamers

      Streptavidin–HRP

      Streptavidin–Sulfo-Tag

      Fluorescent dyes

      Readout platforms: SpectraMax, MSD

    DNA-labeled aptamers

      Signal amplification and readout by qPCR

4.      How do aptamers compare with anti-ID antibodies as binding reagents?

Feature

Aptamers

Antibodies

Binding origin

In vitro selection (SELEX)

In vivo immune response

Target size range

Small molecules to proteins

Primarily proteins

Low-immunogenic targets

Excellent

Often difficult

Conformation-specific binding

Strong

Limited

Batch-to-batch consistency

Very high (chemical synthesis)

Variable (biological production)

Lot replacement risk

Low

Low to high (mAb vs pAb)

Chemical modification

Easy and precise

More complex

Stability (thermal, pH)

Moderate to high

High

Sandwich assay compatibility

Target-dependent

Well established

Regulatory familiarity

Growing

Very high

5.      What assay sensitivity can aptamers achieve?

In applications where aptamers are well suited, they can often achieve ~10× higher sensitivity than anti-ID antibodies.

    Typical sensitivity range:

      Low pg/mL to several hundred fg/mL, depending on assay design and signal amplification strategy.

6.      Do aptamers perform consistently across different batches?

Yes. Aptamers are chemically synthesized, resulting in excellent batch-to-batch consistency and minimal lot variability.

7.      What is the timeline for aptamer reagents?

a)       Pre-developed aptamers: shipped within a few days

b)       Customized aptamers (e.g., signal conjugation, stability modification): 4–10 weeks

c)       De novo aptamer screening for new biomarkers: 2–4 months