Effect of Surface Functionality of Silica Nanoparticles on Cellular Uptake and Cytotoxicity

Abstract

Mesoporous silica nanoparticles (MCM-41) with different surface chemistry were used as carrier system to study its influence on drug delivery and anticancer activity of curcumin (CUR). CUR was encapsulated in pristine MCM-41 (hydrophilic and negatively charged), amino functionalized MCM-41 (MCM-41-NH2 which is hydrophilic and positively charged), and methyl functionalized MCM-41 (MCM-41-CH3 which is hydrophobic and negatively charged) and evaluated for in vitro release and cell cytotoxicity in human squamous cell carcinoma cell line (SCC25). Various techniques were employed to evaluate the performance of these materials on cellular uptake and anticancer activity in the SCC25 cell line. Both positively and negatively charged surfaces demonstrated enhanced drug release and anticancer activity compared to pure CUR. Positively charged nanoparticles showed higher cell uptake compared to negatively charged nanoparticles owing to its electrostatic interaction with cells. However, hydrophobic surface modified nanoparticles (MCM-41-CH3) showed no improvement in drug release and anticancer activity due to its poor wetting effect. Cell cycle analysis and cell apoptosis studies revealed different pathway mechanisms followed by the positively and negatively charged nanoparticles but exhibiting similar anticancer activity in SCC25 cells.

pH-controlled Release System for Curcumin based on Functionalized Dendritic Mesoporous Silica Nanoparticles

“…It can be concluded, that Cur had been completely converted to a non-crystalline state. This is consistent with the previous studies [36,46,48]. It was shown that non-crystalline form of the drug placed in mesoporous silica can present increased solubility [45].…”

“…Cur exhibited several peaks, one at 806 cm -1 due to γ(CH) of aromatic and skeletal CCH [57], a band of peaks was observed in region (1000-1300 cm -1 ) which can be attributed to the symmetric and asymmetric configurations of C-O-C chains, peak at 1436 cm -1 was attributed to CH2 bending, while peak at 1502 cm -1 due to C=O and C=C vibration, peak at 1626 cm -1 C=O stretching, peak at 2840 cm -1 was assigned to C-H stretching of methyl group, peak at 3014 cm -1 was due to C-H stretching of aromatic ring, and peak at 3507 cm -1 was attributed to free -OH group vibration [36].…”

“…It was reported that the silica nanoparticles functionalized with aminopropyl groups are suitable for regulated and controlled release of Cur. It could be attributed to relatively slight hydrophobicity owing to the aminopropyl chain of APTES, leading to slower influx of liquid media into the pores, finally delaying the dissolution of Cur [36]. In addition, APTES would impart some steric hindrance inhibiting the release of Cur from mesopores of nanoparticles [72].…”

“…As curcumin is a promising pro-drug, a few studies have been reported recently on curcumin delivery based on MSNs. Their aim was to enhance the cytotoxicity of curcumin and exploit the effect of surface functionality on cellular uptake and anticancer activity when utilizing the MCM-41 type [35,36], as well as curcumin-loaded guanidine for combating breast cancer using KIT-6 silica type [37] and controlled release of curcumin from hollow silica material [38,39]. However, to the best of our knowledge no reports on utilization of KCC-1 silica type in delivery of curcumin as model anticancer natural pro-drugs yet reported, and also no comparative study to analyze the differences between the KCC-1 material and commonly used MCM-41 type in controlled release of the small molecule drugs has been carried out.…”

Glycyrrhetinic acid-functionalized mesoporous silica nanoparticles as hepatocellular carcinoma-targeted drug carrier

“…25 The mixture was stirred for 24 h at 30°C. The synthesized MSN-NH 2 was collected by centrifugation, washed six times with ethanol, and vacuum dried at 60.0°C for 24 h.…”