Bioactive Hybrids Containing Artificial Cell Membranes and Phyto-Gold-Silver Chloride Bio-Nanoparticles

Abstract

This research targets the need for eco-friendly strategies in the synthesis of bioactive materials, addressing the importance of valorization of vegetal waste. This study focuses on developing biohybrids containing biomimetic lipid vesicles and phytosynthesized gold-silver chloride nanoparticles (AuAgCl NPs) derived from Achillea millefolium L. extract. By leveraging the natural antioxidant and antimicrobial properties of the plant, the research proposes a sustainable approach to creating materials with potential biomedical applications. The biomimetic membranes were loaded with chlorophyll a, a natural spectral marker. Three types of bioactive materials (biohybrids) were developed by varying the lipid vesicle/AuAgCl NP ratio. Optical (UV-Vis, fluorescence emission, FTIR), structural (XRD), elemental (EDX, XPS), and morphological (TEM) studies were performed to characterize the bio-developed materials. The hydrophobic/hydrophilic characteristics of the samples were investigated by measuring the water contact angle, and their size was estimated by DLS and TEM. Zeta potential measurements were used to evaluate the physical stability of phyto-developed particles. Antioxidant properties of phyto-particles were investigated through the chemiluminescence technique. The obtained biomaterials exhibited high antioxidant activity and antiproliferative activity against HT-29 and B-16 cancer cells. Therapeutic index values were calculated for each biohybrid. Additionally, the bio-prepared hybrids revealed biocidal action against Staphylococcus aureus and Enterococcus faecalis. The phyto-developed biomaterials are promising in biomedical applications, particularly as adjuvants in cancer therapy.

Keywords: Achillea millefolium L.; antioxidant activity; antimicrobial properties; antiproliferative activity; gold–silver chloride nanoparticles; phytosynthesis.

Figure 1

Optical characterization of Achillea-derived samples. (a) UV-Vis absorption spectra of yarrow-derived AuAgClNPs and the biohybrids (the spectra were normalized at their characteristic peak). (b) Fluorescence emission spectra of chlorophyll-containing samples (λ_excitation = 430 nm). The lipid vesicles are in the same concentrations as in the biohybrids. (c) Comparative presentation of FTIR spectra of the obtained samples.

Figure 2

XRD patterns of the obtained samples. The diffraction peaks are marked using the symbols: ∗ (magenta) for Au; • (red) for AgCl; ◈ (blue) for NaCl.

Figure 3

CTEM images (a,d,g), HRTEM images (b,e,h), and EDX spectra (c,f,i) obtained on the investigated samples.

Figure 4

XPS spectra of the AuAgClNP sample: (a) survey spectrum; (b) Ag3s and K2s spectrum; (c) Cl2s spectrum; (d) Au4f spectrum.

Figure 5

The wetting properties of Achillea-derived samples.

Figure 6

Antioxidant activity of the obtained samples estimated using the chemiluminescence technique.

Figure 7

The in vitro antimicrobial activity of developed samples, expressed as diameters of the growth inhibition zone (IGZ, mm) evaluated by the agar well diffusion method.

Figure 8

Cell viability curves recorded for all samples: (A)—Lipo, (B)—Extract, (C)—AuAgClNPs, (D)—L1, (E)—L2, (F)—L3, following 24 h of treatment for the three cell lines: L929, B16, and HT-29.

Figure 9

Morphological evaluation by the SEM of L929 cells grown in different conditions for 24 h: (A) control cells and cells treated with liposomes, (B) the extract, (C) AuAgClNPs, (D) L1, (E) L2, (F) and L3 (G). The scale bar is 4 µm.

Figure 10

Schematic representation of the phyto-design of biohybrids containing yarrow-derived AuAgClNPs. The figure was created with Chemix (https://chemix.org/, accessed on 27 September 2024), PowerPoint (Windows 10 version), and Paint 3D (Windows 10 version), & Office 365.