[en] Labelled compound of CTMP that are used for bone seeking radiopharmaceuticals must have to fulfill the standard requirements, such as have high radiochemical purity. CTMP compounds was in house synthesized from cyclam and formaldehyde in an acidic condition (conc. HCl) using Mannich methods. Impurities in CTMP product are the residue of cyclam, phosphoric acid, formaldehyde and hydrochloric acid. Formaldehyde and hydrochloride acid in the aqueous form is easily removed through the rinse process in the synthesis, while cyclam in the solid phase could be mix with CTMP. Therefore the impurities of cyclam in ^99mTc-CTMP must be determined. With nuclear technique, the determination of cyclam could be assessed simultaneously with labelled of CTMP with technetium-99m. Separation of ^99mTc-CTMP and ^99mTc-cyclam in solution was conducted with radio-electrophoresis method simultaneously. The radiochemical purity for both radiolabelled compound was determined by paper chromatography. The purity of radiolabelled ^99mTc-CTMP from cyclam was determined using electrophoresis method. The result show that the amount of cyclam in CTMP can be determined simultaneously using nuclear techniques with the labeling of ^99mTc-CTMP. Electrophoresis method can separated ^99mTc-cyclam, ^99mTc-CTMP, ^99mTcO4 and ^99mTc-reduced with limit quantitation of cyclam until 0,4% w/w. (author)