| dc.description.abstract | ABSTRAK
NABILA PUTRI APRILIA. Pengembangan Metode Penentuan Kadar Total Fosfat
dengan Reduksi Asam Askorbat secara Spektrofotometer Sinar Tampak. Dibimbing
oleh SRI MULIJANI dan EVITA RAHMAWATI.
Fosfat merupakan salah satu parameter penting dalam penilaian kualitas air,
karena konsentrasinya yang tinggi dapat menyebabkan eutrofikasi dan kerusakan
ekosistem perairan. Penelitian ini bertujuan mengembangkan dan memvalidasi
metode spektrofotometer untuk mengukur fosfat total dalam air sungai dengan
menggunakan reduksi asam askorbat. Penelitian ini memodifikasi waktu destruksi
dengan memperpanjangnya menjadi 45 menit, menggantikan waktu standar 30
menit, serta menambah volume reagen campuran amonium molibdat-asam askorbat
dari 2 mL menjadi 2,5 mL. Validasi metode dilakukan sesuai dengan standar SNI
6989.31:2021 dengan menguji tujuh parameter validasi. Hasil validasi yang
diperoleh menghasilkan kurva kalibrasi linear dengan R² =0,995 pada rentang 0,1
1,3 mg/L, MDL 0,0525 mg/L, LOQ 0,167 mg/L, presisi ketertiruan 1,325%, presisi
keterulangan 1,212% dan %Recovery CRM 97,68%-102,32%. Ketahanan metode
diuji pada dua spektrofotometer berbeda menunjukkan hasil konsisten.
Kata kunci: destruksi, fosfat, reduksi asam askorbat, spektrofotometri, validasi
metode | |
| dc.description.abstract | ABSTRACT
NABILA PUTRI APRILIA. Development of a Method for Determining Total
Phosphate Content by Ascorbic Acid Reduction using Visible Light
Spectrophotometer. Supervised by SRI MULIJANI and EVITA RAHMAWATI .
Phosphate is an important parameter in water quality assessment, as its high
concentration can cause eutrophication and damage aquatic ecosystems. This study
aims developed and validated a spectrophotometric method for measuring total
phosphate in river water using ascorbic acid reduction. The study modified the
digestion time by extending it to 45 minutes, replacing the standard tine of 30
minutes, and increased the volume of the ammonium molybdate-ascorbic acid
reagent mixture from 2.0 mL to 2.5 mL. Method validation was conducted
according to the SNI 6989.31:2021 standard by testing seven validation parameters.
The validation results produced a linear calibration curve with an R² = 0.995 over
the range of 0.1–1.3 mg/L, a method detection limit (MDL) of 0.0525 mg/L, a limit
of quantitation (LOQ) of 0.167 mg/L, intermediate precision of 1.325%,
repeatability of 1.212%, and CRM recovery between 97.68% and 102.32%. The
method’s ruggedness was tested on two different spectrophotometers and
demonstrated consistent results.
Keywords: ascorbic acid reduction, method validation, river water,
spectrophotometry, total phosphate | |
