In molecular biology, biotechnology, and diagnostics, microplates may seem like a simple consumable. Yet, these small, multi-well plates have a big influence on the accuracy, reproducibility, and quality of experimental results. Beyond just holding samples, they’re essential tools that bridge biology, chemistry, and technology.

Interesting facts and studies of note

While many researchers treat microplates as interchangeable, recent studies have revealed just how much their physical and chemical properties affect data quality:

• Surface variability impacts assay results.
  A 2017 study, “Variability in Microplate Surface Properties and Its Impact on ELISA”, found that differences in surface roughness and wettability across microplates—and even between wells in the same plate—can cause measurable variation in assay performance. The authors noted that surface treatment methods, such as γ-irradiation, influenced protein binding and detection reproducibility. 

• Microplates influence reproducibility in screening assays.
  The Assay Guidance Manual highlights that “microplates are a critical yet often overlooked component for enabling robust, reproducible biological assays.” The authors found that even small manufacturing changes between production lots can affect signal strength, assay sensitivity, and variability.

• Material choice affects detection performance.
  An application note by Molecular Devices demonstrated that polystyrene, commonly used for optical clarity, can exhibit significant background absorbance in the UV range. Alternative materials such as cyclic olefin copolymer (COC) or quartz glass provide lower background and higher precision in absorbance assays. 

• High-density plates amplify small inconsistencies.
  As laboratories move from 96- to 384- or 1536-well formats, minor geometric inconsistencies—such as uneven well depth or surface coating—can multiply across thousands of wells, leading to systemic bias in large-scale screening campaigns.

These findings reinforce a key insight: microplates are not neutral platforms—they’re active components that can determine whether your data is reliable or misleading.

Implications for your lab or purchasing decisions

Given their impact on assay performance, procurement teams and lab managers should treat microplate selection with the same diligence as choosing reagents or instruments. Here are practical takeaways to ensure consistent, high-quality results:

1. Evaluate microplates during assay development.
   Test multiple plate types or surface treatments early in assay design. Small pilot runs help identify differences in signal-to-noise ratio, background variation, or “edge effects” before scaling up to full experiments.
2. Ask suppliers for technical and quality documentation.
   Reliable manufacturers should provide detailed datasheets on plate materials, surface treatments, lot traceability, and recommended applications. This information supports regulatory compliance and simplifies internal validation.
3. Validate each new lot internally.
   Lot-to-lot variability can occur even within the same product line. Establish acceptance criteria (e.g., background signal limits, CV thresholds) and run quick qualification assays when new lots arrive.
4. Match the plate to your detection method.
• Use black plates for fluorescence to minimize crosstalk.
• Choose white plates for luminescence to maximize reflected light.
• Opt for clear-bottom plates when microscopy or imaging is required.
• For UV or absorbance assays, select low-background materials like COC or quartz.
5. Consider automation and workflow integration.
   In high-throughput or regulated environments, verify that plate dimensions, skirts, and sealing options are compatible with your pipetting robots, washers, and readers. Minor mismatches can disrupt workflow and introduce variability.
6. Don’t underestimate the cost of variation.
   While a premium plate might cost more upfront, it can save significant time and resources by preventing assay failures or inconsistent results. As Assay Guidance Manual experts note, “the choice of microplate should rarely, if ever, be sacrificed due to cost.”

“Microplates are a critical yet often overlooked component for enabling robust, reproducible biological assays.”
— Douglas S. Auld et al., Assay Guidance Manual

In summary

Microplates may not get much attention in the lab, but their quality and consistency directly shape the reliability of your results. Understanding their materials, coatings, and manufacturing differences can help you select the right plate for each application—ensuring reproducibility, accuracy, and long-term confidence in your data.

At ProLab Supply, we provide microplates and labware designed to meet the standards of modern biotechnology and diagnostic research. Explore our selection of microplates to find options optimized for your workflow and assay type.

Sources:

• Auld D.S., Coassin P.A., Coussens N., et al. “Microplate Selection and Recommended Practices in High-throughput Screening and Quantitative Biology.” Assay Guidance Manual (2020). NCBI Bookshelf
• C. Blenner et al. “Variability in Microplate Surface Properties and Its Impact on ELISA.” J Appl Lab Med, 2(5): 687–698 (2017). PubMed
• Molecular Devices. “Effects of Microplate Materials on UV Absorbance Measurements.” Molecular Devices
• “Choosing the Right Microplate for Assay Success.” Biomat Applications & Techniques. biomat.it