Anti-blastocystosis activity of antioxidant coated ZIF-8 combined with mesoporous silicas MCM-41 and KIT-6

Abstract

The biocompatible hybrid Zeolitic imidazolate framework-8 (ZIF-8)/structured silica nanocomposite can be loaded with antioxidants such as curcumin and resveratrol to offer multiple advantages of drug functionalization and structural stability. blastocystosis, an enteric parasite, has various outcomes and its treatment includes drugs which have side effects and do not result in a full cure. We aimed to design novel biocompatible nanocomposites containing natural antioxidant, resveratrol or curcumin and ZIF-8/mesoporous silica. We also assessed their anti-blastocystosis activities as bioactive novel nanocomposites. The nano-silica (MCM-41 and KIT-6) was synthesized using a hydrothermal technique and made composite with ZIF-8 using an ultrasonic technique. The antioxidants, curcumin and resveratrol, were loaded over ZIF-8/MCM-41 and ZIF-8/KIT-6 using a rotary evaporator technique to form novel nanocomposites with bioactive properties. The formulated nanocomposites were characterized. To test their biological activity, suspension of cultured blastocystosis cysts (subtype 3) were exposed to increasing concentrations of nanocomposites and the minimal lethal concentration of each nanocomposite was calculated. The bioactive nanocomposites (ZIF-8/KIT-6, ZIF-8/KIT-6/Resveratrol and ZIF-8/MCM-41/Curcumin) were formulated. Anti-blastocystosis activity of the tested nanocomposites was both dose and time dependent. ZIF-8/KIT-6/Resveratol showed the maximum percentage of growth inhibition (~ 100%) at a concentration of 500 µg/ml after 5 h of exposure. More than 90% of blastocystosis cysts' growth was significantly inhibited at all concentrations of ZIF-8/MCM-41/Curcumin, with different times of exposure, while it occurred only at the highest concentration of ZIF-8/KIT-6 (800 µg/ml). Using cheap, simple, reproducible and scalable techniques, we nano-formulated innovative bioactive nanocomposites, by incorporating the bioactive ZIF-8 (Zn²⁺ with imidazole), structured mesosilica and natural antioxidant compounds, curcumin or resveratrol, to generate multifunctional modalities. These eco-friendly, naturally based, safe, economical, biocompatible, and bioavailable nanocomposites are potential nanotherapeutics. The anti-blastocystosis results of these three nanocomposites indicate their potentially promising innovative and safe use as alternative Blastocystosis therapies.

Figure 1

X-ray diffraction pattern of (a) ZIF-8, (b) Resveratrol, (c) Curcumin, (d) MCM-41/ZIF-8/Curcumin, (e) KIT-6/ZIF-8/Curcumin, (f) MCM-41/ZIF-8/Resveratrol and (g) KIT-6/ZIF-8/Resveratrol nanocomposites.

Figure 2

(A) Nitrogen adsorption isotherm pattern of (a) MCM-41, (b) MCM-41/ZIF-8, (c) KIT-6 and (d) KIT-6/ZIF-8. (B,C) Shows the transmission electron microscope images of KIT-6/ZIF-8 at magnification of 200 nm and 20 nm, respectively.

Figure 3

(A) FTIR spectra of (a) Resveratrol, (b) ZIF-8, (c) MCM-41, (d) MCM-41/ZIF-8/Resveratrol and (e) KIT-6/ZIF-8/Resveratrol nanocomposites. (B) FTIR spectra of (a) Curcumin, (b) MCM-41/ZIF-8/Curcumin and (c) KIT-6/ZIF-8/Curcumin nanocomposites.

Figure 4

Diffuse reflectance spectra of (a) KIT-6/ZIF-8, (b) Resveratrol, (c) Curcumin, (d) MCM-41/ZIF-8/Curcumin, (e) KIT-6/ZIF-8/Curcumin, (f) MCM-41/ZIF-8/Resveratrol and (g) KIT-6/ZIF-8/Resveratrol nanocomposites.

Figure 5

Release profile of antioxidants loaded nanocomposites at 37 °C for 96 h (a) Resveratrol (pH = 5.6), (b) MCM-41/ZIF-8/Resveratrol (pH = 5.6), (c) MCM-41/ZIF-8/Resveratrol (pH = 7.4), (d) KIT-6/ZIF-8/Resveratrol (pH = 5.6), (e) KIT-6/ZIF-8/Resveratrol (pH = 7.4), (f) KIT-6/Curcumin (pH = 5.6), (g) KIT-6/ZIF-8/Curcumin (pH = 5.6) and (h) MCM-41/ZIF-8/Curcumin (pH = 5.6).

Figure 6

Reduction in the percentage of blastocystosis cysts viability after exposure to increasing concentrations of ZIF-8/Kit-6/Resveratrol nanocomposite.

Figure 7

Reduction in the percentage of blastocystosis cysts viability after exposure to increasing concentrations of ZIF-8/MCM-41/Curcumin nanocomposite.

Figure 8

Reduction in the percentage of blastocystosis cysts viability after exposure to increasing concentrations of ZIF-8/KIT-6 nanocomposite.

Figure 9

Trypan blue dye exclusion stained blastocystosis cysts, 400 × magnification. Live blastocystosis cysts (yellow arrows) (control group). Dead blastocystosis cysts (blue arrows). Disintegrated blastocystosis cysts (red arrows).