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The diagnosis of dengue infection is still a critical factor determining success in the clinical management and treatment of patients. Here, the development of microfluidic paper-based analytical devices (μPADs) utilizing a sandwich immunoassay on wax patterned paper functionalized with anti-dengue NS1 monoclonal antibodies for point-of-care detection of dengue NS1 (DEN-NS1-PAD) is reported. Various assay conditions, including the length of the channel and diluent, were optimized, and the response detected by the naked eye and digitized images within 20–30 min. The DEN-NS1-PAD was successfully tested in the field for detecting dengue NS1 in buffer, cell culture media, and human serum. The limit of detection (LoD) of the DEN-NS1-PAD obtained with the naked eye, scanner, and a smartphone camera was 200, 46.7, and 74.8 ng mL−1, respectively. The repeatability, reproducibility, and stability of the DEN-NS1-PAD were also evaluated. High true specificity and sensitivity in the serum of pediatric patients were observed. These evaluation results confirm that the DEN-NS1-PAD can potentially be used in point-of-care dengue diagnostics, which can significantly impact on the spreading of mosquito-borne diseases, which are likely to become more prevalent with the effects of global warming.

Rifampicin, isoniazid (INH) dan pirazinamid merupakan Obat Anti Tuberkulosis (OAT) yang tersedia dalam bentuk Fixed Dose Combination (FDC). Sediaan FDC ini lebih praktis dalam penggunaannya sehingga dapat meningkatkan kepatuhan pasien Tuberkulosis (TB) dalam mengkonsumsi obat. Namun pada beberapa penelitian masih ditemukan FDC yang subdosis yang dapat mengakibatkan pengobatan TB menjadi kurang optimal dan meningkatnya risiko resistensi OAT. Tujuan penelitian ini adalah mengembangkan metode analisis baru yaitu Kromatografi Lapis Tipis (KLT)-Densitometri yang memiliki validitas baik sehingga dapat menjadi alternatif metode analisis yang lebih mudah, cepat, murah dan praktis. Validasi metode yang dilakukan meliputi pengukuran linieritas, presisi, akurasi, batas deteksi dan batas kuantitasi. Parameter hasil validasi metode dibandingkan dengan persyaratan yang ada di Association of Official Analytical Chemist (AOAC) dan United States Pharmacopeia (USP) untuk penetapan kadar FDC. Sampel FDC yang mengandung rifampicin, INH dan pirazinamid dapat dipisahkan dengan fase gerak berupa n-heksan: 2-propanol: aseton: amonia: asam format dengan perbandingan 3:3,6:3:0,3:0,1 (v/v/v/v) dan nilai Rf yang diperoleh untuk rifampicin adalah 0,85, INH 0,6 dan pirazinamid 0,7. Hasil penelitian menunjukkan bahwa metode KLT-Densitometri dapat dikembangkan dan semua parameter validasinya memenuhi persyaratan AOAC. Hasil koefisien korelasi (r) rifampicin 0,999, INH 0,999 dan pirazinamida 0,999, perolehan kembali rifampicin 101,00 %, INH 94,36 % dan pirazinamid 95,69 %; nilai % RSD presisi rifampicin 0,55 %, INH 0,96 %, dan pirazinamid 0,98 %; nilai batas deteksi rifampicin 10,91 ppm, INH 10,38 ppm dan pirazinamid 42,14 ppm; nilai batas kuantitasi rifampicin 33,07 ppm, INH 31,45 ppm dan pirazinamid 127,7 ppm. Kadar terukur (mg) rifampicin, INH, dan pirazinamid per tablet adalah 157,37 mg, 75,26 mg dan 400,79 mg yang berarti sesuai dengan standar yang ditetapkan oleh USP. Kata kunci: KLT-Densitometri, rifampicin-INH-pirazinamid, validasi ABSTRACT Rifampicin, isoniazid (INH) and pyrazinamide are anti tuberculosis drugs (ATD) available in fixed dose combination (FDC) form. The FDC is more practical in usage so can improve tuberculosis patient obedience in consuming the drug. However, in some researches, there are still found subdose of FDC. Subdose of FDC that effected in less optimal TB medication and increase risk of ATD resistance. The high TB case in developing countries such as Indonesia require test of FDC drug dose evaluation. Objective of this research was to develop new analytical method, Thin Layer Chromatography (TLC)-densitometry having good validity so it may be easier, faster, cheaper and more practical analytical method alternative. Validation parameters consist of linearity, precision, accuracy, Limit Of Detection (LOD), and Limit Of Quantitation (LOQ). Parameter of method validation results was compared with requirement in Association of Official Analytical Chemist (AOAC) and United States pharmacopeia (USP) for determine active ingredient in sample. FDC sample containing rifampicin, INH and pyrazinamide can be separated with n-hexane: 2-propanol: acetone: ammonia: formic acid with proportion of 3:3.6:3:0.3:0.1 (v/vv/v) as mobile phase and Rf value for rifampicin, INH, and pyrazinamide were 0.85, 0.6, and 0.7, respectively. The results indicated that TLC-densitometry can be developed and all validation parameters complied with AOAC requirements. The correlation coefficient (r) of rifampicin 0.999, INH 0.999 and pyrazinamide 0.999; recovery of rifampicin, INH and pyrazinamide were 101.00 %, 94.36 % and 95.69 %, respectively. In addition, precision, % RSD for rifampicin, INH and pyrazinamide were 0.55 %, 0.96 %, and 0.98 % respectively; LOD for rifampicin, INH and pyrazinamide were 10.91 ppm, 10.38 ppm and 42.14 ppm, respectively; LOQ for rifampicin, INH and pyrazinamide were 33.07 ppm, 31.45 ppm and 127.7 ppm, respectively. Concentration of rifampicin, INH and pyrazinamide in a tablet were 157.37 mg, 75.26 mg and 400.79 mg that comply with USP standard. Keywords: rifampicin-isoniazid-pyrazinamide, TLC-densitometry, validation