Evaluation of cytotoxicity, biophysics and biomechanics of cells treated with functionalized hybrid nanomaterials

Abstract

Hybrids consisting of carboxylated, single-walled carbon nanotube (c-SWNT)-silver nanoparticles (AgNPs)-DNA-poly vinyl alcohol (PVA) are synthesized via sequential functionalization to mimic the theragnostic (therapy and diagnosis) system. Carboxylation of SWNT has minimized the metal impurities with plenty of -COOH groups to produce hybrid (c-SWNT-AgNPs). The hybrid is further wrapped with DNA (hybrid-DNA) and encapsulated with PVA as hybrid composite (HC). Materials were tested against human alveolar epithelial cells (A549), mouse fibroblasts cells (NIH3T3) and human bone marrow stromal cells (HS-5). The composition-sensitive physico-chemical interactions, biophysics and biomechanics of materials-treated cells are evaluated. The cell viability was improved for HC, hybrid-PVA and c-SWNT when compared with SWNT and hybrid. SWNT and hybrid showed cell viability less than 60% at high dose (40 mg ml 21 ) and hybrid-PVA and HC retained 80% or more cell viability. The treatment of hybrid nanomaterials considerably changed cell morphology and intercellular interaction with respect to the composition of materials. Peculiarly, PVA-coated hybrid was found to minimize the growth of invadopodia of A549 cells, which is responsible for the proliferation of cancer cells. Surface roughness of cells increased after treatment with hybrid, where cytoplasmic regions specifically showed higher roughness. Nanoindentation results suggest that changes in biomechanics occurred owing to possible internalization of the hybrid. The changes in force spectra of treated cells indicated a possible greater interaction between the cells and hybrid with distinct stiffness and demonstrated the surface adherence and internalization of hybrid on or inside the cells.

Cardiomyoblast (H9c2) Differentiation on Tunable Extracellular Matrix Microenvironment

“…21 Briefly, the combined inverted optical stage helped precise lateral positioning of the AFM tip over the region of interest in target materials. The scan size was adjusted to 100 · 100 mm 2 to accommodate typical surface features while maintaining a high resolution.…”

A critical review of nanohybrids: synthesis, applications and environmental implications

“…[197] Similarly a stiffness increase attributable to fullerene encapsulation inside CNTs may also have physical interaction mediated toxicological consequences (Fig. 4g).…”

Investigation of cellular responses upon interaction with silver nanoparticles

“…12,28 Briefly, cells were cultured on Thermanox coverslips placed in a 12-well culture plate at a density of 2×10 5 cells per well in respective media at 37°C in a humidified atmosphere containing 5% CO 2 . Cells were allowed to attach overnight and before the addition of fresh media.…”

“…12,17,18 Recent reports underscore the important role of AFM in biomedical studies including the mechanical properties of stem cells involved in lineage specification, 19,20 mechanics-based cancer diagnosis, 21 investigation of bacterial resistance to antibiotics, 22 detection of aging cartilage and osteoarthritis, 23 stem cell differentiation by matrix elasticity, 24 molecular-molecular interaction, 25 and protein-cell adhesion. 26 Hence, the application of AFM to the study of interfaces has begun to reveal the interaction between cells and NPs at picoNewton (pN) sensitivity and high accuracy.…”

“…9 The forces that drive nano and biological systems could explore their ability of sensing, adhesion, and targeted protein binding by appropriate integration of cytotoxicity. 12,13 Thus, evaluating their mechanism of action at the nanoscale level, as well as the interactions that occur at the interface of biological systems and NPs will facilitate their successful transition into multiple biomedical applications. 10 While several studies have reported the mechanisms that underlie NP-dependent cytotoxicity, 14,15 the understanding of the biophysical and biomechanical properties of cells after NPs treatment seems to be limited.…”