## 1 Introduction  
Nanotechnology is a rapidly expanding branch of technology that holds enormous potential for the chemical [1], medicinal [2], engineering [3], and food-processing industries [4]. This rapid development of nanotechnologies suggests that nanoscale production will soon be used in almost every area of science and technology. Metal oxide NPs have attracted a great deal of interest in a variety of disciplines, including biological [5], industrial [6], optical [7], catalytic [8], pharmaceutical [9], and healthcare applications [10] due to their exceptional surface area and nanoscale size properties. It is speculated that the widespread use of these metal oxide nanoparticles may expose people to their possibly dangerous environment. Because of the potential for cell membrane leakage caused by their toxicity, more environmentally friendly synthesis routes must be developed. Eco-friendly, sustainable materials, including plant extracts, bacteria, fungi, and enzymes, have several advantages in terms of eco-friendliness and compatibility for biomedical applications, as risky chemicals are not required for the production of ZnO NPs. ZnO nanoparticles are an important class of metal oxide nanoparticles exhibiting exciting biological and photocatalytic properties due to their small size and enhanced surface chemical reactivity [11]. However, the majority of conventional techniques for producing ZnO NPs are based on wet chemical route options, which demand the use of numerous hazardous chemicals during laborious, prolonged multistep processes that result in the production of vast quantities of hazardous byproducts and dangerous chemical waste [12]. In recent years, the use of more sustainable green techniques for preparation has been a catalyst for replacing harmful traditional chemicals with more environmentally friendly extracts from various natural materials, such as plants, fungi, bacteria, and algae, to prepare ZnO NPs; These NPs have demonstrated comparable and even higher activities compared to conventional ones. For instance, _Eucalyptus_[13], _Pholmis_[14], _pomegranate_[15], _Syzygium cumini_[16], and _Ziziphus_[17] have been used as plant part extracts for the green biosynthesis of ZnO NPs, with plant extracts utilized as capping agents and stabilizers to both maintain the generated nanoparticles' stability and prevent their aggregation [18]. ZnO-NPs produced using green methods are safe for the environment and have also been used for biomedical purposes due to their antioxidant, antibacterial, and anticancer properties [19; 20]. Selecting the appropriate plant source to prepare the extracts is a crucial step to obtaining ZnO NPs with the correct physicochemical properties, since phenolic chemicals in plant extracts play a crucial role in nanoparticle formation and development. It is important to note that _C. spinosa_ L. is one of the Middle East region's most widely used plants and is distinguished by a variety of medicinal properties. The plant boasts numerous long chains of natural compounds that could serve as capping and stabilizing agents and preclude the nanoparticles from aggregating [21; 22]. Thus, this study aimed to investigate a simple and effective method for producing potent, eco-friendly ZnO nanoparticles utilizing high-purity fruit extract from _C. spinosa_ L. as a reducing and stabilizing agent. Moreover, the morphological and structural features of the green biosynthesized ZnO NPs were characterized using Field Emission Scanning Electron Microscopy (FESEM), X-ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR). In addition, the antioxidant activity, cytotoxicity, and hemocompatibility were evaluated.