In a typical TLC experiment, the radioactivity is detected at two points: after TLC it is analyzed by autoradiography, to locate radioactive spots. These spots are then scraped off of the plate and counted to provide quantitative information. Each of these steps can be enhanced using the following protocols.

Autoradiography and LSC with TLC Plates

Autoradiography (Fluorography)

After the plate has been developed, spray twice with National Diagnostics' Autofluor and allow the plate to dry. This impregnates the plate with phosphors, which will convert the b emissions to more readily detectable photons. Autofluor enhances the speed and sensitivity of detection when the plate is placed on film. Follow this link for details on autoradiography procedures.

Liquid scintillation counting of scraped TLC silica

Option 1: Suspend the silica powder in 10ml of a cocktail that has a gel phase with water, such as National Diagnostics' Ecoscint GL. Shake well, and add 3ml H₂O. Shake until gel forms, and count.

Option 2: Suspend the silica in 10ml of an organic-based (non-emulsion) cocktail such as National Diagnostics' Ecoscint O. Add 0.5-1g finely divided silica thixotrophic agent to form a clear gel in the solution, keeping the TLC particles suspended. Count as usual.

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