Aplikasi Carbon nanotube (CNT) dalam metode pengobatan kanker dapat dilakukankarena menghasilkan selektivitas dan efektivitas targeting obat yang tinggi.Fungsionalisasi CNT diperlukan untuk memperbaiki dispersibilitas, solubilitas, dantoksisitas CNT. Fungsionalisasi dilakukan secara kovalen dengan oksidasi asam yangterdiri dari campuran HNO3 dan H2SO4 dengan penambahan asam klorida (HCl).Variasi yang dilakukan adalah konsentrasi HCl 6M, 8M, 10M, dan 12M pada suhu sonikasiC. CP-f dikarakterisasi dengan uji dispersi, Fourier Infrared TransformationSpectroscopy (FTIR), Thermal Gravimetry Analysis (TGA), UV-Vis Spectroscopy,Electron Miscroscopy-Energy Dispersive Spectroscopy (SEM-EDS), dan Brine ShrimpLethality Test (BSLT). Hasil penelitian menunjukkan bahwa CP-f dengan penambahanHCl 10M (CPf-3) menghasilkan persen solubilitas tertinggi 11,46% dan suspensi dispersiyang paling stabil pada hari ke-51. Disamping dari peningkatan dispersibilitas dansolubilitas, morfologi sampel CPf-3 membentuk beberapa aglomerat yang mengarahkanpada kemunculan sifat dengan nilai LC50 355,62 ppm Carbon nanotube application in cancer treatment methods is selected due to its highselectivity and effectivity in drugs targeting delivery. Functionalization is needed toimprove dispersibility, solubility, and toxicity of CNT. CNT is treated covalently byoxidation which consist of HNO3 and H2SO4 with the addition of HCl. Variation isperformed in HCl concentration of 6M, 8M, 10M, and 12M at sonication temperature of The addition of HCl in certain molarity increase the purity and dispersion timeon functionalized CNT (CP-f). CP-f were characterized through dispersion test, FourierInfrared Transformation Spectroscopy (FTIR), UV-Vis Spectroscopy, ThermalGravimetry Analysis (TGA), Electron Miscroscopy-Energy Dispersive Spectroscopy(SEM-EDS), and Brine Shrimp Lethality Test (BSLT)The study resulted that CP-f withHCl 10M addition (CPf-3) produce the highest solubility for 11.46% and the most stabledispersion suspension in 51 days. Besides, CPf-3 morphology shows some agglomerateswhich indicate to toxicity with LC50 of 355,62 ppm |