STUDI PENENTUAN KADAR Cu, MG, MN, ZN DALAM TABLET MULTIVITAMIN-MINERAL SECARA SPEKTROFOTOMETRI SERAPAN ATOM

STUDI PENENTUAN KADAR Cu, MG, MN, ZN DALAM TABLET MULTIVITAMIN-MINERAL SECARA SPEKTROFOTOMETRI SERAPAN ATOM

ABSTRAK Telah dilakukan penelitian tentang penentuan kadar Ca. Mg, Mn, Zn dalam contoh tiruan tablet multivitaminmineraldengan- metoda SSA. Penelitian ini perlu dilakukan karena penentuan kadar Cu, Mg, Mn, Zn dalam contoh tablet tersebut belum banyak diteliti. Padahal, homopnitas logam-logam tersebut (karena kadarnya kecil, yaitu 0,1%) dapat digunakan sebagai salah satu indikator kesempurnaan proses produksi tablet yang bersangkutan. Penelitian ini bertujuan mengetahui pengaruh Ca (75ag-250mg) dan Fe (45mg-82mg) yang terdapat dalam campuran Cu (1 mg), Mg (6 mg), Mn (1 mg), Zn (1,5 mg) terkadap hasil recovery keempat logam tersebut dan mendapatkan cara mengatasi pengar,uh yang ditimbulkan oleh Ca dan Fe contoh, tersebut. Diteliti juga pengaruh cara penyiapan yaitu cara pengabuan kering, cara pengarangan *spat dan cara pelarutan langsung dalam 0,5 N HC1, tarhadap hasil recovery keempat logam tersebut. Hasil penelitian ini menunjukkan bahwa jika diguanakankurva standar logam analit (tunggal), recovery Cu, Ma. Mn, Zn di dalam campuran keempat logam tersebut adalah berturut-turut 101,92%, 101,14%, 91,65%, dan 97.88%. Jika digunakan kurva standar logam campuran, yang dibuat berdasarkan larutan standar yang mengandung viii

ix campuraan garam-garam Cu-Mg-Mn-Zn, maka recovery Cu, Mg, `. Zn (dalam campurannya bersama Ca dan Fe) adalah : Cu (18.85Z- 102,36%), Zn (100,18%-101,49%), Mg (114,09%- 1 15.93X), Mn (115,01%-117,08%). Pengaruh Ca dan Fe terhadap recovery Mg dan Mn tersebut ternyata dapat diatasi dangan penambahan sejumlah tertentu LaC1 3. Recovery Cu, Mn, Zn dalam contoh tiruan tablet tidak dipengaruhi oleh ketiga cara penyiapan contoh yang d iteliti. Tetapi, recovery -Mg dengan cara pelarutan langsung dalam 0,5N HC1 (105,89%) lebih rendah daripada recovery Mg dengan eara pengabuan kering (109,47%) maupun dengan cara pengarangan cepat (107,54%). Jadi, penyiapan contoh untuk analisa Cu, Mg, Mn, Zn dalam tiruan tablet multivitamin-mineral sebaiknya dilakukan dengan cara pengarangan cepat. Sedang kurva kalibrasi yang digunakan pada analisa Cu, Mg, Mn, Zn terse but sebaiknya dibuat berdasarkan larutan-larutan standar yang mengandung campuran logam Cu-Mg-Mn-Zn. Khusus untuk analisamn dan Mg sebaiknya ke dalam larutan contoh ma upun larutan standar yang digunakan ditambahkan larutan LaCl 3 masing-masing 24.10-3 M dan (2.10-3 M - 6.10-3 M). Penentuan kadar logam-logam tersebut dalam tablet asli nasih memerlukan penelitian lebih lanjut.

ABSTRACT The determination of Cu, Mg, Mn, Zn in a mixture isolating multivitamin-mineral tablets was investidated. those This experiment was done since the analysis of elements in multivitamin-mineral tablet is not well documented in the literature. Whereas, the degree Of homogeneity of these elements in the tablets (because Of the smallness of their concentrations, i.e. about O.1Z) may be used as one indicator for the correctness of the tablet production process. The aim of this experiment was to know the- influonce of Ca (75mg-250mg) and Fe (45mg-82mg) present in a fixture (1.5mg) containing Cu (1mg), Mg (6mg), Mn (1mg), Zn on the recovery of these foul elements and how to overcome the influences of Ca and Fe. The influence of Ca and fe procedures of sample preparation (dry ashing, rapid ashing and acid extraction procedures) on the detoraination of Cu, Mg, Mn, Zn has also been examined. The results indicate that, by using single-metal standard curves, the percentage recoveries of Cu, Mg, Oh. and Zn in their mixture were respectively 101,92, 101.14, 91,65 and 97,88. By using a mixed-metal standard curve based on standard solutions containing a mixture of Cu, Mg, Mn, Zn is was found that the percentage recoveries of Cu, x

xi mg, Mn, Zn in the presence of Ca and Fe were in the range of 98,85-102,36 for Cu, 100,18-101,49 for Zn, 114,09-115,93 for Mg and 115,01-117,08 for Mn. The interferences caused by Ca and Fe on the recovery of Mg and Mn were overcome by the addition of lanthanum chloride (LaC1 3 ). The recoveries of Cu, Mn, Zn in the simulation mixture were not influenced by the three sample preparation procedures mentioned. But if-the acid extraction procedure was used, the Mg recovery was lower than if either the dry ashing or the rapid ashing procedures were employed. It may be concluded that the preferred sample preparation procedure for the determination of Cu, Mg, Mn, Zn in the simulation mixture was the rapid ashing procedure. Further, the mixed-metal standard curves based on standard solutions containing a mixture of Cu, Mg, Mn and Zn should be used as calibration curves in the analyses of these four elements. Especially for the analyses of Mg and Mn certain concentrations of lanthanum chloride solutions should be added both to the sample and to the mixed-metal standard solutions, i.e. in the range of 2.10-3 M - 6.10-3 M for Mg and 24.10-3 M for Mn. The determination of these elements in original tablet samples has still to be investigated further.