ONCYTE® AVID Porous Nitrocellulose Film Slides — Colorimetric, Chemiluminescent & Fluorescence Detection

ONCYTE^® porous nitrocellulose film slides are the gold standard substrate for protein microarray applications, trusted by researchers worldwide for their exceptional binding capacity, broad dynamic range, and reproducible performance. Manufactured under ISO 13485-certified quality standards, each ONCYTE^® slide features a microporous nitrocellulose film cast onto a solid substrate — creating a three-dimensional protein capture surface that dramatically outperforms conventional functionalized glass. ONCYTE^® AVID porous nitrocellulose film slides are the most versatile substrate in the ONCYTE^® family — the only nitrocellulose microarray slide fully compatible with colorimetric, chemiluminescent, and fluorescence detection systems in a single formulation. Built on a 12 µm microporous nitrocellulose film cast onto a solid glass substrate, AVID's thick three-dimensional porous architecture delivers an exceptionally large protein capture surface, immobilizing significantly more protein per spot than conventional functionalized glass slides. With a contact angle of 80° — the most hydrophobic surface in the ONCYTE^® line — AVID produces tight, well-defined spots with minimal lateral spreading, making it the substrate of choice for high-density printing of antibodies, antigens, glycoproteins, and complex tissue lysates. Whether your laboratory runs western-blot-style colorimetric detection, chemiluminescent imaging, or fluorescence scanning, ONCYTE^® AVID delivers consistent, high-sensitivity performance without requiring a substrate change between platforms.

Why ONCYTE^® Film Slides?

ONCYTE^® porous nitrocellulose film slides deliver three core performance advantages that set them apart from conventional microarray substrates:

High Protein Binding Capacity — The microporous three-dimensional architecture of ONCYTE^® nitrocellulose film creates a vastly expanded available surface area compared to flat functionalized glass slides. This translates directly into more protein captured per spot, stronger signal output, and greater assay sensitivity — particularly important for low-abundance target detection in complex biological samples such as cell lysates and serum.

Fluorescence Signal Amplification via the Tyndall Effect — When excitation light strikes the porous nitrocellulose surface, tiny voids within the film scatter incident photons back onto fluorophores — effectively increasing the probability of excitation and amplifying fluorescence signal without additional reagents or amplification steps. The result is a higher signal-to-noise ratio and a lower detection limit than non-porous substrates can achieve.

Broad Dynamic Range and Low Detection Limit — ONCYTE^® film slides deliver 5 to 7+ orders of magnitude of fluorescence dynamic range depending on formulation, enabling accurate quantification across a wide spectrum of protein concentrations in a single experiment. This broad dynamic range makes ONCYTE^® slides exceptionally well-suited for quantitative applications such as RPPA, biomarker validation, and dose-response profiling.

ONCYTE^®AVID — Colorimetric & Chemiluminescence Detection

ONCYTE^® AVID porous nitrocellulose film slides are engineered for researchers who demand maximum protein binding capacity with versatile detection compatibility. Cast as a 12 µm microporous nitrocellulose film on a solid substrate, AVID's thick porous architecture delivers an exceptionally large available surface area — capturing and retaining significantly more protein per spot than conventional functionalized glass slides. With a contact angle of 80°, AVID's highly hydrophobic surface promotes tight, well-defined spot morphology, making it ideal for high-density microarray printing. Spanning a 5–6 log dynamic range, ONCYTE^® AVID is uniquely compatible with colorimetric, chemiluminescent, and fluorescent detection systems — making it the most versatile substrate in the ONCYTE^® family and the preferred choice for antigen and antibody binding assays, cell and tissue lysate arrays, glycoprotein profiling, and peptide binding applications where detection flexibility is as important as binding performance.

How to Choose the Right ONCYTE^® Film Slide

Applications

Primary Applications

• Antigen-capture microarrays: high-density immobilization of purified antigens for antibody screening and serology assays
• Antibody binding arrays: capture antibody panels from complex matrices including serum, plasma, and cell lysate with minimal background
• Tissue and cell lysate microarrays: spot complex protein mixtures directly onto AVID's high-capacity porous surface for expression profiling
• Glycoprotein microarrays: immobilize glycoproteins and lectins for binding interaction studies across sample panels
• Peptide binding assays: print overlapping peptide libraries for epitope mapping and antibody specificity screening
• Multi-platform detection workflows: the only ONCYTE® variant compatible with colorimetric, chemiluminescent, and fluorescence detection in the same experiment

Detection Methods Supported

• Colorimetric detection: compatible with standard chromogenic substrates and western blot reagents
• Chemiluminescent detection: compatible with HRP-conjugated secondary antibodies and ECL substrates
• Fluorescent detection: compatible with all major fluorescence scanners and labeled secondary antibodies

Technical Resources

Everything you need to get started with ONCYTE^® film slides — from product selection to advanced protocols:

Product Documentation

• ONCYTE^® Product Offering — AVID, NOVA, and SuperNOVA overview (PDF)
• ONCYTE^® Flyer and Selection Guide (PDF)
• User Guide — ONCYTE^® Protein Microarrays (PDF)

Protocols

• SYPRO Ruby Staining of ONCYTE^® Porous Nitrocellulose Film Slides
• Fast Green Staining of ONCYTE^® Porous Nitrocellulose Film Slides with Near-IR Detection

Frequently Asked Questions

Why choose AVID over NOVA or SuperNOVA for fluorescence detection?
AVID is the right choice when your laboratory uses multiple detection platforms or when you need colorimetric or chemiluminescent detection compatibility. If you are running exclusively fluorescence-based assays and do not need multi-method flexibility, NOVA offers a slightly thinner 7 µm film that provides equivalent sensitivity with more controlled wetting behavior. AVID's 12 µm film and 80° contact angle deliver the highest hydrophobicity in the ONCYTE^® family, making it ideal for very high-density printing where spot containment is critical.

Can I use standard western blot blocking buffers with ONCYTE^® AVID?
Yes — ONCYTE^® AVID is the only ONCYTE^® variant for which standard western blot blocking buffers such as 1–5% non-fat milk in PBS or TBS are routinely recommended. This is because AVID supports colorimetric and chemiluminescent detection, where protein-based blocking buffers are standard practice. For fluorescence detection on AVID, switch to a fluorescence-optimized blocking buffer such as SuperG™ to minimize background autofluorescence from milk proteins.

What is the optimal protein concentration for printing on ONCYTE^® AVID?
For purified proteins and antibodies, a printing concentration of 0.1–1.0 mg/ml is recommended. The upper end of this range is appropriate for antibodies and glycoproteins. For complex lysates, titration across a concentration series (typically 0.1–2.0 mg/ml total protein) is recommended to identify the linear detection range for your targets.

Is ONCYTE^® AVID compatible with automated microarray printers?
Yes. ONCYTE^® AVID is compatible with all major contact and non-contact microarray printing platforms, including pin-based arrayers, piezoelectric dispensers, and inkjet printing systems. Printing should be performed at 50–55% relative humidity to prevent sample evaporation. No pre-treatment or activation of the slide surface is required prior to printing.

Can I use ONCYTE® AVID for RPPA (reverse-phase protein array) applications?
ONCYTE^® AVID can support RPPA workflows, however ONCYTE^® SuperNOVA is strongly preferred for RPPA applications due to its 7+ log dynamic range — significantly wider than AVID's 5–6 log range. For samples spanning a very wide concentration range, SuperNOVA will deliver more accurate quantification across the full dilution series. AVID is the better choice for RPPA experiments where colorimetric or chemiluminescent detection is required.

How does the Tyndall effect improve performance on ONCYTE^® AVID?
The Tyndall effect occurs when excitation light passes through the microporous nitrocellulose film and scatters off the tiny voids within the porous matrix. These scattered photons are reflected back toward the bound fluorophores, effectively increasing the probability of excitation and amplifying fluorescence signal without any additional reagents or amplification steps. On ONCYTE^® AVID, this results in a higher signal-to-noise ratio and a lower limit of detection compared to non-porous glass substrates — even when using the same antibody concentrations and detection reagents.

What protein concentrations should I print on ONCYTE^® Film Slides?
For purified proteins, a concentration of 0.05–1 mg/ml is optimal for most applications. The upper end of this range is recommended for antibodies. Concentration optimization may be required for specific proteins or complex mixtures such as cell lysates.

Does printing need to be performed at low temperature?
No. Printing may be performed at room temperature as long as humidity is maintained at approximately 50–55% to prevent sample evaporation during the spotting process.

Can my protein sample contain urea?
Yes. Samples containing urea are routinely printed on ONCYTE^® Film Slides without performance impact. ONCYTE^® slides are chemically resistant to reagents commonly used in cell analysis assays, including up to 50% formamide. Note that acetone, ethanol, and methanol are not recommended — isopropanol and butanol are suitable substitutes. DMSO concentration should not exceed 5% as higher concentrations may negatively affect nitrocellulose integrity.

Can I use standard western blot blocking buffers?
The optimal blocking buffer depends on your detection method. Colorimetric and chemiluminescent detection workflows are compatible with standard western blot blocking buffers such as PBS or TBS containing 1–5% non-fat milk. For fluorescent detection, protein-based blocking buffers can introduce background fluorescence — SuperG™ Protein Array Blocking Buffer has been specifically optimized for fluorescent microarray assays and delivers a high signal-to-noise ratio with minimal background.

What detection systems are compatible with ONCYTE^® Film Slides?
ONCYTE^® Film Slides are compatible with virtually all detection systems, including isotopic, chemiluminescent, chromogenic, and fluorescent detection. AVID offers the broadest detection compatibility across all four variants.

How should I store printed and non-printed ONCYTE^® slides?
Non-printed slides should be stored at room temperature in their original packaging. Printed slides may be stored at 4°C for short-term storage or at -20°C for long-term storage. An overnight incubation at 4°C after printing is recommended to maximize protein binding before use.

What controls should I include in my microarray experiment?
IgG pre-labeled with a fluorophore should be spotted on every array to confirm proper protein binding. Buffer-only spots enable background subtraction, and secondary antibody-only stained slides serve as negative controls. Spotted replicates for each protein are strongly recommended to ensure statistical confidence in your results.

Can ONCYTE^® Film Slides be stripped and re-used?
No. Re-use of ONCYTE^® Film Slides is not advisable. Each slide is designed for single-use to ensure consistent, reproducible results.