In Vitro Cytotoxicity Assays

Identifying potential toxicity at early research stages allows to optimize new compounds development.

Cell-based assays with high flexibility.
time optimisation
Full cell functionality after transportation.
Validation data available and high-quality control standards.


Advancing cell toxicity evaluation with ready-to-use cell-based plates.

CacoReady 96 Transwell


Measure and stratify the cellular toxicity of your new molecular entity by evaluating TEER resistance and LY Paracellular Flux.

CacoReady 96 Multiwell


A simple colorimetric method to screen compound cytotoxicity.

cover application notes

Say goodbye to outdated colorimetric assays!

Our new application notes on CacoReady plates will show you how to accurately predict and stratify intestinal compound toxicity evaluating the TEER value and the LY paracellular flux, two relevant indicators of the cell barrier integrity.


Ensure the safety of your new molecule

healthy gut
LEAKY GUT - ReadyCell

Drug-induced gastrointestinal reactions are one of the main causes of post-market drug withdrawal. These adverse effects can potentially be predicted by in vitro assays, since these side effects, like diarrhea, correlate with intestinal barrier dysfunction. In this regard, the most commonly used models for intestinal drug studies in pharmaceutical research consist of human intestinal epithelial cells, such as the colon adenocarcinoma cell line Caco-2.

There is a growing interest in using in vitro cytotoxicity tests instead of in vivo test systems to assess the cell viability of new molecular entities. This approach offers several advantages like reducing the need for animal testing, lowering costs, and speeding up the development and availability of these molecules. Although we should be cautious when comparing results from in vitro and in vivo tests due to their complexity, it is often observed that short-term cytotoxicity tests show positive responses that align well with short-term in vivo implantation tests.


Cell toxicity testing and stratification in transwell plates



Frequently Asked Questions

What are the differences between transwell, no-transwell and individual transwell?

Caco-2 cells seeded on transwell inserts allow them to differentiate and polarise with an apical and basal surface which is mandatory to establish their barrier function. The Transwell system let using cell barrier disruption as an indicator of compounds’ toxicity. Transwells can be either integrated or singles, the latter recommended for assays requiring individual mobility at different time periods or measurements.

The non-Transwell format contains differentiated but not polarised Caco-2 cells. Late-stage indicators through colourimetric tests are used to measure the adverse effects of tested compounds.

For an effective cytotoxicity assay protocol, as well as a permeability assay protocol, it’s crucial to consider the choice of well system carefully.

What do the current regulations establish on the basis of cell toxicity tests?
According to the European and the American Regulatory Agencies (EMA and FDA), acute toxicity studies are recommended for pharmaceuticals intended for human use.
Which are the main reference compounds for CacoReady and what are the differences between them?
The reference compounds used in these tests are Nadolol, Quinidine, Verapamil, and Gemfibrozil, described as diarrhea-causing side effects with a known grade of toxicity incidence (moderate to high). Nadolol is used as their non-toxic counterpart.
Is it possible to add a testing service to the order?
As a general rule, we act as a supplier and do not provide testing services. Nonetheless, feel free to contact us if you wish to test our plates externally. We can direct you to our partners who can assist you in conducting the assay effectively. Additionally, in certain situations, we are open to collaborating to try out new applications of interest to both of us.
Which reagents are suitable for cell viability assays using non-transwell plates?
ReadyCell recommends using AlamarBlue, and MTT or WST assays to test compounds’ cytotoxicity in the CacoReady plates. The former employs resazurin as an indicator of cell viability and can be measured using colorimetric or fluorescence detection. MTT and WST are colorimetric cell-based assays that use tetrazolium salts reduction to quantify the number of viable cells. These agents have been extensively used and proven to be compatible with our plates, ensuring accurate and reliable results.
Is the quality control data specific for each kit?
Yes, we provide a concrete quality control for each batch so the customer can have a reference for the kit before and after shipment.
Does ReadyCell shipping medium affect cell lines?

No, ReadyCell’s Shipping Medium consists of a semi-solid culture system specifically designed to preserve cells at room temperature (15-25ºC). This medium maintains a suitable physicochemical environment, keeping adequate moisture conditions for cellular homeostasis and forming a protective cushion that protects cell integrity and functionality during long-distance shipments up to seven days.

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