Cytotoxicity of Formulated Graphene and Its Natural Rubber Nanocomposite Thin Film in Human Vaginal Epithelial Cells: An Influence of Noncovalent Interaction

Abstract

Graphene family materials (GFMs) are extensively explored for various biomedical applications due to their unique physical properties. The prime challenge is to establish a conclusive safety profile of these nanomaterials and their respective products or devices. Formulating GFMs with appropriate ingredients (e.g., surfactant/compatibilizer) will help to disperse them homogeneously (i.e., within the polymer matrix in the case of polymer–graphene nanocomposites) and aid in good interfacial interaction to achieve the desired properties. However, no cytotoxicity report is available on the effects of the additives on graphene and its incorporated materials. Here, we report in vitro cytotoxicity of formulated FLG (FLG-C), i.e., a mixture of FLG, melamine, and sodium poly­(naphthalene sulfonate) (SPS), along with natural rubber (NR) latex and FLG-C-included NR latex nanocomposite (FLG-C-NR) thin films on human vaginal epithelial (HVE) cells. FLG-C shows reduced cellular proliferation (∼55%) only at a longer exposure time (72 h) even at a low concentration (50 μg/mL). It also displays significant down- and upregulation in mitochondrial membrane potential (MMP) and reactive oxygen species (ROS), respectively, whereas no changes are observed in lactate dehydrogenase (LDH), propidium iodide (PI), uptake, and cell cycle analysis at 48 h. In vitro experiments on NR latex and FLG-C-NR latex thin films demonstrate that the incorporation of FLG-C does not compromise the biocompatibility of the NR latex. Further substantiation from the in vivo experiments on the thin films recommends that FLG-C could be suitable to prepare a range of biocompatible rubber latex nanocomposites-based products, viz., next-generation condoms (male and female), surgical gloves, catheters, vaginal rings, bladder–rectum spacer balloon, etc.

Design of a New Coating Agent Based on Graphene Oxide and Antimicrobial/Spermicidal Peptide (Sarcotoxin Pd) for Condom Coating: New Strategy for Prevention of Unplanned Pregnancy and Sexually Transmitted Infections

“…Graphene condoms are thinner than regular condoms. Due to the high strength of the graphene layer, it is possible to design a thinner condom [34,35]. This point causes the heat to be better directed, and couples experience more sexual pleasure in addition to ensuring pregnancy prevention.…”

“…In our study, covalent interaction was used. Sukumar et al [34] showed that the functionalization of graphene with the right ingredients (e.g., surfactant/compatibilizer) could increase its dispersion and aid in good interfacial interaction to achieve the desired properties. This point is not excluded from using graphene in the design of condoms.…”

Graphene in rubber formulations: a comprehensive review and performance optimization insights

“…The biocompatibility test reveals that the nanocomposite with undiluted graphene causes acute toxicity to the cell, whereas the nanocomposite with diluted graphene has no toxic effects. 78 This might be due to the reduction in direct contact with the cell in the low graphene-loading nanocomposite. The skin irritation and sensitization test show no significant damage indicating that the graphene nanocomposite can be used for healthcare products such as a catheters, condoms, and gloves.…”

Graphene and water-based elastomer nanocomposites – a review

“…In addition, recent cytotoxicity study (conducted via both in vitro and in vivo) on G-WBEC utilising FLG/Natural rubber (FLG-C-NR) nanocomposite revealed that graphene incorporation within the NR matrix do not compromise its biocompatibility, as no sign of toxicity, nor skin irritation were observed for up to 48 hours exposure [188]. However, majority of the available literature results suggests that graphene toxicity (as well as its susceptible environmental effects) is largely attributable to the overall nature of the surface chemistry (functionalised sites, especially the reactive oxygen species dominant in the derivatives such as GO), particle size, number of layers, concentration of the graphene material [189], [190] and the processing techniques employed in the graphene production [180].…”