Pengembangan Sensor Kimia Berbasis Kertas untuk Penentuan Kadar Flavonoid Total Ekstrak Daun Jambu Biji - Mochammad Amrun Hidayat; Husnatul Ayniah; Indah Yulia Ningsih; Tanfidz Alishlah; Bambang Kuswandi (ALCHEMY Jurnal Penelitian Kimia, 2025)
Sensor kimia berbasis kertas adalah piranti analisis yang menggunakan membran berpori berupa kertas untuk imobilisasi reagen kimia dan deteksi analit pada sampel volume kecil (μL – nL). Sensor kimia flavonoid total dikembangkan dengan cara melakukan ko-imobilisasi larutan aluminium klorida (AlCl3), natrium nitrit (NaNO2), dan natrium hidroksida (NaOH) pada kertas menggunakan teknik adsorpsi. Penambahan larutan kuersetin dapat mengubah warna sensor dari putih menjadi kuning yang kemudian dapat ditangkap dan dikuantifikasi dengan program ImageJ, yang dikenal sebagai teknik skanometri. Karakterisasi analitik seperti linearitas, Limit of Detection (LOD), Limit of Quantification (LOQ), presisi dan akurasi sensor dilakukan dengan menggunakan standar kuersetin. Hasil penentuan kadar flavonoid total sampel daun jambu biji menggunakan metode sensor kimia-skanometri menunjukkan kesesuaian dengan metode spektrofotometri, sehingga memiliki potensi sebagai metode alternatif untuk penentuan kadar flavonoid total.Development of Paper-Based Chemical Sensor for Determining The Total Flavonoid Content in Guava Leaf Extract. Paper-based chemical sensors are analytical devices that utilize porous paper membranes for reagent immobilization and analyte detection in small sample volumes (μL – nL). The total flavonoid chemical sensor was developed by co-immobilizing aluminum chloride (AlCl3), sodium nitrite (NaNO2), and sodium hydroxide (NaOH) solutions onto paper by using the adsorption technique. The introduction of a quercetin solution changed the sensor's color from white to yellow, which subsequently can be captured and quantified using the ImageJ program, known as the scanometric technique. The sensor's analytical characteristics, such as linearity, limit of detection (LOD), limit of quantification (LOQ), precision, and accuracy, were evaluated using a quercetin standard. The results of determining the total flavonoid content of guava leaf samples using the chemical sensor-scanometric method showed agreement with the spectrophotometric method, indicating its potential as an alternative method for determining total flavonoid content.