Agar Gel - In this approach, the medium (consisting of a suitable salt solution, serum, chick embryo extract or a mixture of certain amino acids and vitamins) is gelled with 1 % agar. This method avoids immersion of explants into the medium and permits the use of defined media.

Generally, explants need to be subcultured on fresh agar gels every 5-7 days. The agar gels are generally kept in embryological watchglasses and sealed with paraffin wax. The explants can be examined using a stereoscopic microscope. This method has been used to study many developmental aspects of normal organs as well as of tumours.