Direct modification of HLNPs using GTMA: A dispersion of HL60NP (10 mL. particle concentration 1 g L -1 ), was reacted at pH 12 (1 M NaOH) with 40 μl of GTMA for 2 hours at 80 °C. The reacted particles were dialyzed in deionized water for 24 hr. The dialyzed product was in the form of a precipitate that could be redispersed by increasing or decreasing the pH.