EV-Guard™ EV Storage Buffer - 1X

Product Description

EV-Guard EV Storage Buffer (EV-Guard) is an innovative solution designed to safeguard extracellular vesicles (EVs) and maintain their biological activities during storage. With its advanced formulation, EV-Guard effectively preserves the integrity and stability of EVs under various storage conditions, including multiple freeze-thaw cycles. Whether stored at 4°C, -20°C, or -80°C, EV-Guard shields EVs from degradation and ensures their optimal performance.

• Ease of Use - Simply resuspend EV pellets in the 1x EV-Guard buffer or add the 10X concentrated EV-Guard buffer directly to the EV fractions from size exclusion column, making it a quick and easy step to preserve your EVs
• Superior Protection – Achieve up to 98% EV conservation, significantly higher than with PBS, even after multiple freeze-thaw cycles, ensuring your EVs are well preserved and retained for your downstream applications
• Preserve Functionality – EVs have better transfection efficiency in EV-Guard than in PBS after multiple freeze-thaw cycles and long-term storage, assuring your EVs remain biologically active and ready to use

How It Works

The buffer is designed in 1X concentrated format to suit the needs for customers who choose to use different EV isolation methods which result in concentrated EV pellets (e.g., by ultracentrifugation, ExoQuick or other precipitation-based methods).
For EV isolation methods which result in EV suspensions (e.g., by SmartSEC or other size exclusion-based methods), EV-Guard EV Storage Buffer - 10X is recommended.

Using the EV-Guard EV storage buffer – 1X

1. Resuspend purified EV pellet in 100 ul - 500 ul of 1X EV-Guard EV Storage Buffer.
2. Optional: Perform a protein quantitation assay (e.g., BCA or Qubit assay) to determine the amount of protein in your sample.
3. Aliquot EV samples into appropriate volumes for storage.

EV-Guard prevents loss of EV particles after multiple freeze-thaw cycles

The size distribution (A) and the percentage of EV conservation (B) were assessed by NTA following multiple freeze-thaw cycles in both EV-Guard buffer and PBS. The data were derived from five independent experiments (n=5), each compared to a single freeze-thaw cycle.

EV-Guard minimizes loss and aggregation of EV particles during long-term storage

EVs from normal human serum were isolated using SBI’s ExoQuick and stored at 4°C for periods of 0, 15, and 30 days. The percentage of EV conservation (A) and EV size distribution (B) were subsequently analyzed using fluorescent nanoparticle tracking analysis (fNTA).

EV-Guard preserves EV functionality and integrity after long-term storage

GFP-loaded EVs were stored in either PBS (columns 1 and 2) or EV-Guard (columns 3 and 4) at -20°C for 1 month before being introduced to HEK293 cells for transfection (Row C). Row A represents the negative control (no GFP EVs), while Row B is the positive control (no storage). After 1 month at -20°C, the number of GFP+ EVs was analyzed using fluorescent NTA (as shown in the box to the right).