Caltag Medsystems is a UK-based company that specializes in providing high-quality life science products, including antibodies, assays, recombinant proteins, biological samples, and molecular tools. They partner with trusted suppliers, such as Cloud-Clone Corp and KactusBio Inc, to offer a wide range of products for research and diagnostic needs. The company prides itself on its expert support, straightforward ordering process, and UK-based customer service team. Caltag Medsystems is ISO 13485 accredited and holds all necessary ethical documentation, ensuring the quality and integrity of its products and services. They cater to researchers in academia, pharma, and biotech across the UK and Ireland, providing products and services that support scientific discovery and innovation.

Simplifying scientific sourcing since 2001.

Caltag Medsystems Ltd was founded in February 2001 by Dr Tim Almond, beginning operations with a base in Silverstone, UK. Built on the commitment to supporting life science research through high-quality reagents and responsive service, we quickly grew into a trusted partner for researchers across the UK and Ireland.

In 2009, Caltag Medsystems relocated to our current site in Buckingham, to allow for laboratory facilities & the launch of our manufacturing division, Cytomark, which produces specialist reagents for flow cytometry, including the cell stabilisation reagent TransFix®. This marked an exciting new phase, combining scientific expertise in both sourcing and manufacturing under one roof.

Our company continued to strengthen, achieving our first ISO 13485 certification in 2013 and securing FDA clearance in 2017 for the Transfix/EDTA Vacuum Blood Collection Tube (TVT-03-50-US) for in vitro diagnostic use in the United States. In 2018, Caltag was awarded a Human Tissue Authority (HTA) license, enabling the storage of human tissue products in our liquid nitrogen tanks. This means we can maintain the temperature-sensitive integrity of these products whilst we process orders for dispatch.

Most recently, in 2025, Caltag Medsystems and Cytomark were fully unified under the Caltag name in a company-wide restructure to become an employee-owned trust, as well as subsequent rebranding. This transition reflects our continued focus on simplicity and delivering a seamless experience for our customers.

Today, Caltag continues to support scientists across academia, biotech, and pharma by offering globally sourced & trusted reagents and expert guidance from a genuinely approachable team.

With Caltag, source hard-to-find reagents, standard tools and custom services — all in one place. Our portfolio includes a wide range of RUO, GMP and IVD products spanning immunology, cell biology and molecular applications. As a trusted partner of universities and biotech leaders across the UK, with 20+ years of experience, we understand the importance of reliable service and expert support.

Antibodies
Primary Antibodies
Secondary Antibody
Isotype Controls
All Antibodies
Assays and Kits
ELISA Kits
CLIA Kits
Cell Based Assays
Enzymatic Activity Assay Kits
PCR Kits
Protein Extraction, Isolation, and Purification Kits
Biochemical Assay Kits
Flow Cytometry Kits
All Assays and Kits
Biological Samples
Primary Cells
Cell Lines
Isolated Blood, Tissue and Bone Marrow Samples
iPSC Derived Cells
Skin
Cell Culture Media
All Biological Samples
DNA and RNA
Transfection Tools
Clones, Plasmids and Vectors
Genome Editing Tools (CRISPR and TALEN)
RNA and RNA Arrays
DNA and DNA Arrays
Transduction Tools
All DNA and RNA
Proteins, Peptides and other Macromolecules
MHC Tetramers
Recombinant Proteins
Peptides
All Proteins, Peptides and other Macromolecules
Biochemicals, Buffers and Chemical Substrates
Inhibitors and Activators
Compound Libraries
Lysis Buffers
Other Biochemicals
All Biochemicals, Buffers and Chemical Substrates
Labware and Consumables