Abstract

Abcam is proud to offer a comprehensive portfolio of high‑quality primary antibodies trusted by researchers worldwide, including an extensive range of rabbit recombinant monoclonal antibodies. Consistent with historical industry practices, these products were routinely shipped in thermal packaging containing ice packs. Abcam is committed to sustainability and reducing our environmental impact, whilst prioritizing product quality and customer experience. To evaluate the suitability of our flagship rabbit recombinant monoclonal antibodies for ambient shipping, we conducted a structured stability study. The results demonstrate that these antibodies maintain their performance when shipped at ambient temperature, supporting ambient distribution as a reliable, convenient, and more sustainable shipping method that preserves product quality while reducing environmental impact.

Introduction

Abcam is committed to delivering high quality products using convenient, reliable and sustainable practices. As part of this commitment, we have evaluated opportunities to improve our shipping practices and transition from cold chain shipment to ambient temperature shipping for our recombinant primary antibodies.
Ambient shipping provides several meaningful benefits for customers. It eliminates concerns about melted ice packs on receipt and offers greater flexibility in how and when orders are delivered, as products maintain their integrity without temperature-controlled packaging. This shift also reduces the amount of packaging customers need to unpack and dispose of, creating a cleaner and more convenient experience upon delivery.
In addition to benefiting customers, ambient shipping supports more sustainable research workflows by reducing dependence on polystyrene containers, ice packs, and other non‑recyclable cold‑chain materials, and by lowering overall package weight, which in turn decreases transport‑related CO₂ emissions.
Before making any changes to our shipping strategy, it is essential to confirm that product performance remains uncompromised. This study rigorously evaluated the stability of recombinant rabbit monoclonal antibodies by stress‑testing them under conditions that exceed the temperature fluctuations expected during ambient shipping and by maintaining these conditions for an extended seven‑day period. The findings demonstrate that these products remain stable and high-performing, enabling us to update our shipping practices while continuing to support researchers with reliable, high-quality reagents in a more convenient and sustainable way.

Scope of this study

This study focused on nearly 10,000 of Abcam’s rabbit recombinant primary monoclonal antibodies formulated in our standard buffer. Conjugated primary antibodies, as well as BSA and azide free products were not included.

Materials and methods

To support the transition from cold chain to ambient shipping, we conducted a stability study using a statistically representative selection of our recombinant rabbit monoclonal catalog products. These antibodies were subjected to storage at different temperatures and subsequently evaluated for performance using application testing.
To ensure the study reflected the diversity of Abcam’s recombinant rabbit monoclonal antibody portfolio, we used an AQL Level I statistical sampling approach to determine the minimum number of products required. AQL (Acceptable Quality Level) frameworks are widely used in QC to draw representative samples from large populations without exhaustive testing.
Using this method, we identified 80 antibodies from a pool of nearly 10,000 standard‑formulation, unconjugated antibodies, providing a robust representation of the wider portfolio. These 80 antibodies covered a broad range of targets and manufacturing dates. All were supplied in our standard formulation buffer and had been stored at –20 °C prior to testing, consistent with typical product handling and storage.
Each antibody was aliquoted into multiple 100 µL vials and incubated for seven days at 4 °C, 22 °C and 37 °C. These temperatures were chosen to reflect relevant shipping scenarios: 4 °C as a cold‑chain control equivalent to blue‑ice conditions, 22 °C as a standard ambient shipping temperature, and 37 °C as a high‑temperature stress condition that antibodies may encounter briefly during transit. Following incubation, all samples were evaluated using Western Blot (WB) as a primary validation method and/or immunohistochemistry on paraffin‑embedded sections (IHC‑P), employing the same validated methodologies used in routine product qualification and quality control.

Overall performance expectation

Each tested antibody must demonstrate equivalent functional performance to the control antibody stored at +4 °C to be considered a pass. For Western Blot, the signal intensity and banding patterns were analyzed. For IHC-P, the staining intensity and tissue-specific localization were assessed. In total, 66 of the antibodies were tested in WB, 2 were tested in IHC-P and 12 antibodies were tested in both applications.

Results

All 80 antibodies demonstrated performance consistent with the +4 °C controls across 92 total assessments, with no evidence of product degradation or functional defect. This consistency provides strong reassurance that the antibodies maintain their expected functionality under the conditions tested and will perform as intended when used in standard laboratory workflows.
The figures below showcase three representative cases, providing side‑by‑side WB and IHC‑P data that exemplify the stable and reliable performance observed throughout the study’s full panel of antibodies.

Figure 1: Anti-CD14 antibody [SP192] [ab183322]

ab183322 was stored for 1 week at +4 °C, +22 °C, and +37 °C prior to analysis. In the WB image, band intensity remains consistent across all tested temperatures. The IHC‑P panel likewise shows comparable staining intensity and localization, indicating that antibody performance is stable under these conditions.

^{ab183322at 1:100 dilution}

^{Sample:Paraffin-embedded human tonsil tissue}

^{Heat mediated antigen retrieval was performed with Citrate buffer (pH 6.0, Epitope Retrieval Solution 1) for 10 mins. The section was incubated with ab183322 for 10 mins at room temperature. Followed by a ready to use Rabbit specific IHC polymer detection kit HRP/DAB (ab209101). Counterstained with Hematoxylin. The immunostaining was performed on a Leica Biosystems BOND® RX instrument.}

Figure 2: Anti-BMP4 antibody [EPR6211] [ab124715]

ab124715 was stored for 1 week at +4 °C, +22 °C, and +37 °C prior to analysis. In the WB image, band intensity remains consistent across all tested temperatures. The IHC‑P panel likewise shows comparable staining intensity and localization, indicating that antibody performance is stable under these conditions.

^{ab124715at 1:400 dilution}

^{Sample:Paraffin-embedded human kidney tissue}

^{Heat mediated antigen retrieval with Tris-EDTA buffer (pH 9.0, epitope retrieval solution 2) for 20 mins. The section was incubated with ab124715 for 30 mins at room temperature, followed by a ready to use Rabbit specific IHC polymer detection kit HRP/DAB (ab209101). Counterstained with Hematoxylin. The immunostaining was performed on a Leica Biosystems BOND® RX instrument.}

Figure 3: Anti-Sarcomeric Alpha Actinin antibody [EP2529Y]  [ab68167]

ab68167 was stored for 1 week at +4 °C, +22 °C, and +37 °C prior to analysis. In the WB image, band intensity remains consistent across all tested temperatures. The IHC‑P panel likewise shows comparable staining intensity and localization, indicating that antibody performance is stable under these conditions.

^{ab68167at 1:300 dilution}

^{Sample:Paraffin-embedded human skeletal muscle tissue}

^{Heat mediated antigen retrieval with Tris-EDTA buffer (pH 9.0, epitope retrieval solution 2) for 20 mins. The section was incubated with ab68167 for 30 mins at room temperature, followed by a ready to use Rabbit specific IHC polymer detection kit HRP/DAB (ab209101). Counterstained with Hematoxylin. The immunostaining was performed on a Leica Biosystems BOND® RX instrument.}

Discussion

In this study, antibodies were rigorously evaluated under elevated temperatures to model a range of shipping environments, including those encountered in warmer regions. Products maintained excellent stability when held at 22 °C and 37 °C for seven days. Importantly, all products continued to deliver comparable results to the controls upon application testing and functioned as intended. As ambient shipping will only be implemented under conditions where expected temperature exposures remain well within the validated study range, these findings provide strong assurance that antibody performance will be maintained during ambient distribution.

Conclusion

This study provides robust evidence that our recombinant antibodies in standard buffer remain stable and functional under ambient shipping conditions. In line with Abcam’s commitment to rigorous quality assurance, we have taken a careful, data‑driven approach before implementing changes that could impact our customers. Our findings reinforce that ambient shipping delivers the same high‑quality, reliable antibodies our customers expect, while offering a more convenient and sustainable experience for the scientific community.