Cefotaxime Stock Solution 400 mg/mL: Preparation & Usage FAQ

Cefotaxime Stock Solution (400 mg/mL) is a ready-to-use aqueous antibiotic preparation designed to streamline selection and decontamination steps in plant transformation, tissue culture, and other research workflows.

SKU

C1529774

Concentration

400 mg/mL

Solvent

Water (aqueous solution)

Form

Ready-to-use liquid stock solution

Primary Application

Plant tissue culture, Agrobacterium elimination, antibiotic selection

Antibiotic Class

Third-generation cephalosporin (beta-lactam)

What Is Cefotaxime Stock Solution (400 mg/mL)?

Cefotaxime Stock Solution (400 mg/mL) is a pre-formulated, aqueous antibiotic reagent supplied at a high concentration for convenient use in research laboratories. Cefotaxime is a third-generation cephalosporin that inhibits bacterial cell-wall synthesis by binding to penicillin-binding proteins (PBPs), leading to bacterial lysis and death.

The 400 mg/mL concentration is specifically chosen to allow researchers to prepare working solutions at commonly required final concentrations (typically 100–500 µg/mL) through simple dilution, minimizing preparation time and reducing the risk of weighing errors associated with handling antibiotic powders.

Aladdin Scientific supplies this solution under SKU C1529774, formulated in water to ensure compatibility with most aqueous culture media and buffers used in plant biology and microbiology research.

Storage, Stability, and Handling

To maintain potency, Cefotaxime Stock Solution should be stored at −20 °C when not in use. Repeated freeze-thaw cycles degrade beta-lactam antibiotics and should be avoided; it is recommended to aliquot the stock solution into single-use volumes upon receipt.

Once thawed, working aliquots may be stored at 4 °C for short periods (typically up to one week); however, researchers should verify stability under their specific conditions. The aqueous formulation does not require organic solvents such as DMSO or ethanol, which simplifies handling and reduces cytotoxicity concerns when added to sensitive cell or plant cultures.

Always handle antibiotic solutions using aseptic technique to prevent contamination of the stock. Discard any aliquots that show visible particulates, color change, or signs of microbial growth.

How to Prepare Working Solutions

Preparing a working solution from the 400 mg/mL stock is straightforward. Determine the required final concentration for your experiment, then apply the dilution formula: C1 × V1 = C2 × V2.

Example: To prepare 100 mL of a 250 µg/mL working solution, add 62.5 µL of the 400 mg/mL stock to sterile water or medium to a final volume of 100 mL. Filter-sterilize (0.22 µm membrane) if the solution has not been aseptically handled throughout. For heat-sensitive media such as plant tissue culture agar, allow the autoclaved medium to cool to approximately 50–55 °C before adding the cefotaxime working solution to avoid antibiotic degradation.

Typical working concentrations used in plant transformation and Agrobacterium elimination range from 100 to 500 µg/mL, though the optimal concentration should be determined empirically for each experimental system.

Applications in Plant Transformation and Tissue Culture

Cefotaxime is widely used in Agrobacterium tumefaciens-mediated plant transformation protocols. After co-cultivation of plant explants with Agrobacterium, cefotaxime is included in the selection and regeneration media to eliminate residual Agrobacterium cells, which would otherwise overgrow and kill the plant tissue.

Because cefotaxime is a bactericidal agent effective against gram-negative organisms including Agrobacterium species, it is preferred over antibiotics such as carbenicillin or timentin in certain species where phytotoxicity from those alternatives is a concern. However, researchers should be aware that cefotaxime itself has been reported to affect plant regeneration in some species at high concentrations; empirical dose optimization is advised.

Beyond Agrobacterium elimination, cefotaxime may also be employed as a general antibacterial supplement in tissue culture media to prevent bacterial contamination originating from explant surfaces or laboratory environment.

Quality, Regulatory Notes, and Ordering Information

Aladdin Scientific's Cefotaxime Stock Solution (400 mg/mL) is intended for research use only (RUO) and is not approved for human or veterinary therapeutic use. Researchers should consult applicable institutional biosafety and chemical hygiene policies before use.

The product is available under SKU C1529774. For bulk quantities, custom concentrations, or specific lot documentation requests (Certificate of Analysis, Safety Data Sheet), please contact Aladdin Scientific customer service or your regional distributor.

When ordering, ensure that cold-chain shipping is requested to maintain product integrity during transit, as aqueous antibiotic solutions may degrade if exposed to elevated temperatures for prolonged periods.

Frequently asked questions

What solvent is used in Cefotaxime Stock Solution (400 mg/mL)?

The solution is formulated in water (aqueous solution), with no organic solvents such as DMSO or ethanol. This makes it directly compatible with most aqueous culture media and minimizes cytotoxicity concerns in sensitive biological systems.

How should I store Cefotaxime Stock Solution to maintain its potency?

Store the stock solution at −20 °C in single-use aliquots to avoid repeated freeze-thaw cycles, which degrade beta-lactam antibiotics. Thawed aliquots can be kept at 4 °C for up to approximately one week; discard any aliquot showing particulates, discoloration, or microbial growth.

What are typical working concentrations of cefotaxime in plant transformation experiments?

Working concentrations typically range from 100 to 500 µg/mL for Agrobacterium elimination during plant tissue culture and transformation. However, the optimal concentration is species- and protocol-dependent and should be determined empirically, as very high concentrations may exhibit phytotoxic effects in some plant species.

Can cefotaxime be added directly to hot agar medium after autoclaving?

No. Cefotaxime is heat-sensitive, and adding it to hot agar will cause rapid degradation and loss of antibiotic activity. Always allow autoclaved agar medium to cool to approximately 50–55 °C before adding the cefotaxime working solution, and mix gently to ensure homogeneity before pouring plates.

Is Cefotaxime Stock Solution (400 mg/mL) approved for therapeutic use?

No. This product is intended strictly for research use only (RUO) and is not approved or intended for human or veterinary therapeutic, diagnostic, or clinical use. Researchers must comply with all applicable institutional and regulatory requirements when handling this reagent.

References

1. Nauerby B, Billing K, Wyndaele R. Influence of the antibiotic timentin on plant regeneration compared to cefotaxime and carbenicillin in concentrations suitable for elimination of Agrobacterium tumefaciens. Plant Science. 1997.
2. Olhoft PM, Somers DA. L-Cysteine increases Agrobacterium-mediated T-DNA delivery into soybean cotyledonary-node cells. Plant Cell Reports. 2001.
3. Aladdin Scientific. Product Data: Cefotaxime Stock Solution (400 mg/mL), SKU C1529774. Aladdin Scientific internal product documentation.

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.