## 1 Introduction
The majority of these efforts have been directed towards improving HNT dispersion within a polymer, polymer/nanoclay composite compatibility, and functionalizing the HNT surface [28; 29]. [PERSON] et al. (2012), for example, modified hydroxyl groups on the HNT surface to carboxylic acids to show the potential of these hydroxyl groups [30]. The HNT surface has been successfully altered with a variety of organosilanes. [PERSON] et al. (2006) functionalized the HNT surface with \(\gamma\)-aminopropyltriethoxysilane and then polypropylene chains were grafted onto the HNT surface with a resultant increase in mechanical properties compared with polypropylene alone or polypropylene/unmodified HNTs [31]. HNTs were successfully modified with different functionalized organosilanes, and interestingly, the analysis indicated that HNT dispersion in poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) led to various structures depending on the clay organomodifier [32]. The authors concluded that the mechanical properties of HNT/PHBV composites could be altered with the final composition dependent on the clay organomodifier [32]. Furthermore, silane-functionalized HNTs have been developed for many applications in polymer matrices, such as epoxy resin [33], polypropylene [31], natural rubber [34], and ethylene-propylene-diene rubber [35]. In contrast, the area of chemical modification of HNTs via covalent bonding for drug delivery applications is an area that has seen only a few studies using bioactive molecules [36]. In one study, modification of the inner surface using phosphonic acid was reported to produce an increase in drug loading capacity [24]. Another study used molecules grafted onto the surface to create sulfur bridges as a means of glutathione selectivity in addition to pH sensitivity demonstrating an efficient chemotherapeutic delivery system [37]. Here, we describe the synthesis of a bi-functionalized HNT with two different molecules covalently bound to the outer HNT surface. In contrast to healthy cells, tumor cells overexpress specific receptors and tumor-associated surface antigens [38]. Among these, the folate receptor (FR) is overexpressed by a wide range of tumors such as ovary, kidney, colon, breast, and lung cancers [39; 40; 41]. Polic acid (FA), an oxidized form of folate, can bind to the membrane-anchored FRs and increase cellular uptake, which makes it a specific ligand to target FR-overexpressing tumor cells. The addition of FA to the surface of the HNTs will allow for selective targeting of tumors [39; 40]. Furthermore, the addition of fluorescein isothiocyanate (FITC) to the surface creates a method by which the effectiveness of the targeted system can be determined via in vivo imaging [16]. Additionally, this study describes a washing process for the HNTs, post modification, that is not reported in similar studies [24; 33; 37; 42; 43; 44; 45]. The resulting modified HNTs were characterized via FTIR, 13C[H1]CPMAS NMR, and UV-Vis spectroscopy. As a proof of concept, bi-functionalized HNTs (bHNTs) were assessed for cytotoxicity and evaluated for their ability to be internalized by murine colon cancer cells through fluorescent microscopy.