Nanoscience and nanotechnology attract researchers and industrialists to simulate the synthesis and testing of nanoparticles through calculation and experimental procedures [[1], [2], [3]]. This has become important towards the advancement of the science and technology for mankind [[4], [5], [6], [7]]. Further, the inter-disciplinary support expands the area of application of materials in the nano regime depending on their morphology, geometry, chemical and physical properties [[8], [9], [10]]. Based on the materials, nanoparticles (NPs) have been classified as ceramic or oxide NPs [[11], [12], [13], [14]], carbon-based NPs [[15], [16], [17], [18]], metal NPs [[19], [20], [21], [22]], semiconductor NPs [23,24], and polymer NPs etc. [[25], [26], [27], [28]]. Among all these NPs, metal nanoparticles (MNPs) have received significant attention due to their highly tunable optical properties through surface plasmon resonance (SPR) effect with high absorption coefficient [29] and high surface area to volume ratio [30]. With such a wide range of properties, MNPs like silver (Ag) [[31], [32], [33]], gold (Au), copper (Cu) [34], platinum (Pt) [35,36] and palladium (Pd) [[37], [38], [39], [40]] open the door in wide range of applications. This includes electronic storage systems [41,42], biotechnology [43], diagnostics & treatments [44], catalysis [45], biosensor [46], antimicrobial [47], nanomedicine [48], food control [49], coating [50,51], textile industry [52], cosmetic industry [53], drug delivery [54], solar cells [55], water treatment [56,57], supercapacitor [58] and so on.

However, AgNPs are biocompatible along with their metallic properties compared to CuNPs, which has led to extensive research and commercial applications in the MNPs category. AgNPs have been recognized and utilized in various industries especailly food industry as antifungal material [49], in the textile industry as fabric coatings with properties such as anti-stain and anti-bacterial activity [50], in the cosmetic industry as optically active and anti-bacterial material [53], in solar energy harvesting to enhance or fine-tune the light absorption of photovoltaic cells (PV cells) [55], in water treatment as antimicrobial agents and catalysts for the degradation of chemical waste, in environmental protection, in agriculture as an eco-friendly pesticide, and in the health sector as an antimicrobial agent [59]. Moreover, the unique structural and physicochemical properties of AgNPs enable them to penetrate and target abnormal cells, thereby paving the way for novel medical applications such as cancer therapy [48] and drug delivery [54], among others.

However, sudden emergence of pandemic situations including COVID-19 has shaken the world in the last few years. The repercussions of such an outbreak are proven to be long lasting and affect social lives in a complex way. Thus, a new approach and/or sustainable solutions in the all-aligned fields of medical sciences including peripheral health wares and bio-medical instrumentation have indeed been needed [43,60].

In view of this, tailoring of multifunctional properties of AgNPs in order to explore them as a therapeutic agent for such infections could be one of the possible solutions. This can be achieved through the thorough study of the synthesis methods and properties of AgNPs [29]. Initially, research has been well explored on the development of robust methods for AgNPs synthesis [61] which includes chemical methods [62], electrochemical [63], microwave-assisted synthesis [64], photochemical reductions [65] and physical synthesis [66]. Conversely, these methods have precincts viz., involvement of toxic chemicals including reducing and stabilizing agents, the requirement of sophisticated instrumentation, high temperature and/or vacuum technology, impure and low yield with high costs [66].

On the other hand, green and/or microorganism assisted synthesis has replaced conventional chemical and physical methods in recent decades [52]. This involves the integration of the NPs with plant extracts, where the already present bio-organic components in extract would contribute to enhancing the biocompatibility of the AgNPs with hazardous by products [67]. And thus, this offers eco friendliness, non-toxicity, enhanced biocompatibility, cost effectiveness and possible commercial grade mass production [53].

As a prominent avenue of research in nanotechnology, the synthesis of silver nanoparticles (AgNPs) has garnered significant attention owing to their unique physicochemical properties and versatile applications. This review provides a comprehensive overview of the state-of-the-art methodologies for the synthesis of AgNPs, with a particular emphasis on the influential role of key process parameters such as pH, temperature, and concentration of plant extracts, etc. The pH of the reaction medium is a critical parameter that profoundly affects the synthesis of AgNPs. Different pH values can lead to variations in the reduction kinetics, nucleation, and growth processes. For instance, acidic conditions may result in smaller nanoparticles due to faster reduction kinetics, while alkaline conditions often yield larger particles with a better stability. Marciniak et al. [68] found that the size of the Ag nanoparticles synthesized using citric acid and malic acid was found to be influenced by the pH of the reaction system. The size of the nanoparticles increased in the pH range from 7.0 to 9.0 and then decreased rapidly at pH 10.0 and 11.0. A judicious control of pH during synthesis provides a facile means to modulate the size and stability of AgNPs. Temperature also serves as a crucial parameter influencing the thermodynamics and kinetics of AgNP synthesis. Higher temperatures generally accelerate reduction processes, leading to faster nucleation and growth rates. However, excessively higher temperatures may also result in undesired agglomeration. The careful optimization of temperature conditions is imperative for achieving controlled and reproducible synthesis of AgNPs. For example, Liu et al. [69] demonstrated that with the presence of sufficient amount of precursor, the size of the NPs decreases with the increase in the temperature due to the sharp increase in nucleation kinetic constant with a simultaneous decrease in growth kinetic constant. Jayanthi et al. [70] observed that the temperature can significantly affect the shape, size, and band gap (optical property) of synthesized particles. Another important factor is the plant extract that affects the properties of the Ag nanoparticles. Plant extracts are increasingly utilized as green reducing agents for AgNP synthesis due to their eco-friendly and cost-effective nature. The concentration of plant extracts, rich in bioactive compounds, significantly impacts the reduction kinetics and stabilizing properties of the resulting nanoparticles. Fine-tuning the concentration allows researchers to tailor the composition and surface chemistry of AgNPs, influencing their interaction with biological systems [71]. The synthesized AgNPs were found to have more antimicrobial potentials. The hydroglycolic extracts of medicinal plants such as sea buckthorn, sage, calendula, and dittany were used as reducing agents for the synthesis of AgNPs [72]. Apart from pH, temperature, and plant extract concentration, several other parameters, such as reaction time, precursor concentration, and the choice of reducing agents, play vital roles in determining the properties of AgNPs. Understanding the interplay of these factors is essential for the rational design and optimization of synthesis protocols. Overall, the synthesis of AgNPs is a dynamic field with continuous advancements driven by the exploration of various process parameters. This review highlights the pivotal role of pH, temperature, and plant extract concentration in shaping the characteristics of AgNPs. As the field evolves, an interdisciplinary approach integrating chemistry, biology, and materials science will undoubtedly contribute to the development of innovative and sustainable synthesis strategies for silver nanoparticles. Further, the present review has been focused towards the futuristic, simple and cost-effective green synthesis methods to achieve versatile AgNPs with the main focus on plants extracting silver nanoparticles for (i) an antibacterial, (ii) an antimicrobial, and (iii) an antifungal activity within detailed examples.