MWCNTs

100 mg of 5-fluorouracil was dissolved in 10 mL solution containing ethanol:water (1:9) [25]. Subsequently, 800 mg f-MWCNTs were added to this solution with continuous agitation using an ultra sonicator. Thereafter, the resultant mixture was stirred for 3 h, and the dispersion obtained was filtered using membrane filter paper (0.5 μm, Sigma Aldrich) equipped with vacuum filtration assembly. Finally, the residue was washed using ultra pure water. The final drug loaded f-MWCNTs were dried at 40 °C for 24 h [25]. Dry solid product was then stored until further use, whereas the collected filtrate containing unbound 5-fluorouracil was used for the estimation of 5-fluorouracil loading capacity of MWCNTs by using UV–Vis spectrophotometer. The collected filtrate containing unbound 5-fluorouracil was scanned at 280 nm, is the characteristic absorbance wavelength of 5-fluorouracil. Also calibration curve of 5-fluorouracil was accomplished with the parameter. Finally, obtained results were recorded to estimate the drug loading capacity as per Eq. 1; Tarawneh et al. [26].