MATERIALS CHEMISTRY AND PHYSICS, cilt.259, 2021 (SCI-Expanded)
Halloysite nanotubes (HNTs) clay were modified with alkyl halides, bromoethane (BrE), bromodecane (BrD), and bromooctadecane (BrOD), respectively. The FT-IR spectra of modified HNTs demonstrated an increase in the intensity of aliphatic -CH2 peaks at 2920 and 2850 cm(-1) proportional to the number of C atoms in the modifying agent confirming the success of chemical modification with corresponding alkyl halides. Surface charge of NaOH treated HNTs, -65.7 +/- 5.1 mV was increased to -37.1 +/- 2.4, -40.6 +/- 5.3, and -44.7 +/- 1.9 mV, respectively upon chemical modification with BrE, BrD, and BrOD. The Surface area of the HNT clays, 43.2 +/- 1.3 m(2)/g was also increased to 59.8 +/- 2.7, 56.9 +/- 2.1, and 47.9 +/- 1.7 m(2)/g for BrE, BrD, and BrOD modified HNT clays, respectively. Base-activated HNT clays at 1 mg/mL concentration found to be nonhemolytic with 3.5 +/- 1.2% hemolysis ratio, whereas HNT-BrOD clays were slightly exceeded hemolytic safety level with 6.6 +/- 0.2% hemolysis induction. Base-activated HNT and HNT-BrOD clays were found to show antithrombogenic character with more than 100% blood clotting indexes,107.6 +/- 1.8, and 106.5 +/- 1.9%, respectively. Cytotoxicity studies of HNTs on L929 fibroblast cells revealed that HNTs in 12.5-200 mu g/mL concentration range were shown dose-dependent cell viability, and above 50% cell viability was maintained at 200 mu g/mL in all forms of HNT based clays administered.