Keloids are skin disorders or benign tumours that are due to abnormal wound healing in the binding tissue after trauma, inflammation, surgical wounds, or burns. Low activity radioisotopes have shown to be effective in curing or eliminating keloids on the skin. One of these radioisotopes is phosphorus-32 (32 P), a beta (β-) emitter with a half-life of 14.3 days. This radioisotope can also be developed for the treatment of keloid and skin tumours. Currently, the keloid is treated by conventional methods where a filter paper which has been wetted with 32 P in form of its sodium phosphate directly applied on the area of the keloid. However, this method is considered inefficient and less secure. The purpose of this research is to obtain technology for preparing of 32 P-labeled skin patch which is expected to be which will not decompose easily. The first step of this research is to produce 32 P-labeled chromic phosphate (Cr 32 PO 4) colloids, a precursor of skin patch, through condensation which involves oxidation-reduction reaction. In this step, Cr (VI) is reduced to Cr (III) to form Cr 32 PO 4 with a particle size of <1 μm. These particles (Cr 32 PO 4) are expected to evenly distributed when mixed with silicon to form skin patch. The reaction gave a yield of 97,8%. The results of characterization show that the prepared Cr 32 PO 4 colloids have a particle size of > 1μm. Further study needs to be performed in due time in order to have Cr 32 PO 4 colloids with suitable particle size.