VALIDASI METODE DESTRUKSI BASAH TERTUTUP (Hotplate dan Microwave) DAN PENENTUAN KADAR LOGAM TIMBAL (Pb) DALAM KONDISIONER SECARA SPEKTROMETRI SERAPAN ATOM (SSA)

Abstract

Telah dilakukan penelitian tentang validasi metode destruksi basah tertutup (hotplate dan microwave) dan penentuan kadar logam timbal dalam kondisioner secara spektrometri serapan atom (SSA). Langkah-langkah penelitian: 1) validasi metode destruksi (hotplate dan microwave) menggunakan standar Pb(NO3)2. Validasi metode destruksi berdasarkan empat parameter uji yaitu linearitas, presisi, akurasi, LOD/LOQ; 2) uji statistik menggunakan spss serta t-test pada validasi metode destruksi; 3) destruksi sampel kondisioner menggunakan metode destruksi tervalidasi; 4) penentuan kadar logam timbal dalam kondisioner dengan SSA. Hasil menunjukkan bahwa dari kurva kalibrasi didapatkan hasil linearitas logam Pb sebesar 0,9984. Validasi metode destruksi hotplate memiliki nilai %RSD 1,70% sedangkan microwave memiliki nilai %RSD 4,21% sehingga kedua metode tersebut memiliki presisi yang baik karena nilai %RSD < 10,19, nilai recovery pada hotplate 93,31% dan microwave 91,43% sehingga kedua metode tersebut memiliki akurasi yang baik karena memenuhi syarat %recovery yaitu 70-115%. Nilai LOD diperoleh sebesar 1,056 ppm dan nilai LOQ diperoleh sebesar 3,520 ppm. Berdasarkan uji t-test, diperoleh metode destruksi basah tertutup terbaik yaitu motode destruksi hotplate. Kadar rata-rata timbal yang diperoleh dari sampel A sebesar 3,104 mg/L. Hasil tersebut menunjukkan sampel A masih memenuhi syarat standar batas kadar logam timbal pada kosmetik yaitu < 20 ppm. A research of the validation of closed wet destruction methods (hotplate and microwave) and determination of lead metal content in a conditioner by atomic absorption spectrometry (AAS) has been done. Stages of this research were: 1) validation of destruction methods (hotplate and microwave) using Pb(NO3)2 standard. Validation of destruction method based on four test parameters including linearity, precision, accuracy, and LOD/LOQ; 2) statistical test using spss and t-test on validation of destruction method; 3) destruction of sample conditioner using validated destruction method; 4) determination of lead metal content in conditioner with AAS. The results showed that from calibration curve, the linearity of lead metal was 0.9984. The hotplate method validation had a value of RSD 1.70% while the microwave method has a value of RSD 4,21% so both methods had good precision because a value of RSD < 10.19%, value recovery on hotplate was 93.31% and microwave was 91.43% so both methods have good accuracy because it met the percentage of recovery requirement that was 70-115%. LOD value obtained was 1.056 ppm and LOQ value obtained was 3.520 ppm. Based on the t-test, the optimal closed wet destruction method was the hotplate destruction method. The average of lead content obtained from sample A was 3.104 mg/L. The results showed that sample A still met the standard limit of lead metal content in cosmetic that was < 20 ppm.