The work presented in this dissertation comprises of synthesis, spectroscopic analyses and biological evaluation of silver and gold based pronanomedicines derived from fluoroquinolones. Among others, it includes convenient and time saving production of noble metals (Ag/Au) nanoparticles (NPs) capped with fluoroquinolone antibiotics (moxifloxacin (Mox), ciprofloxacin (Cip), sparfloxacin (Sp) and gemifloxacin (Gm). Different reducing agents such as triethylamine, hydroquinone and sodium borohydride were employed to transform Ag/Au salts into feasible capping agents. Among them, sodium borohydride relatively gave better results. As for we understand and based on FTIR data, the NH moiety of fluoroquinolones were mainly responsible for the capping of Ag/Au nanoparticles. In order to manifest alternate green method, Ag and Au NPs were also produced by using selected medicinal plants; Rhododendron arboreum (RA), Kigelia pinnata (KP) and Eulophia dabia (ED) as reducing and stabilizing agent, while triethylamine was used to synthesize NPs of the extract of Desmodium elegans (DE). The structural framework and size morphology of synthesized NPs were characterized by using advanced analytical techniques such as atomic force microscope (AFM), UV visible, fourier transform infrared spectroscope (FTIR), energy dispersive X-ray (EDX) and scanning electron microscope (SEM). To find alternate to wide spread resistive strains of pathogenic microbes; new antimicrobial agents are needed to treat the patients infected with such resistive pathogenic microbes. The locally synthesized pronanomedicines derived of fluoroquinolones were evaluated for biological properties namely urease inhibition, leishmanicidal, antimicrobial and antioxidant activities. Interestingly and as for our expectations, these NPs enhanced biological and pharmacological activities. The synthesized pronanomedicines and the capping ligands were independently screened for jack bean urease enzyme inhibition potential. Mostly, the Ag-Mox NPs exhibited higher level of enzyme inhibition activity of 93% at 0.2 mg/mL and IC50 value of 0.66 ± 0.042 μg/mL concentration, while the ligand; Mox revealed weak inhibition with IC50 value of 183.25 ± 2.06 μg/mL. On the other hand, the Au-Mox NPs remained inactive as compared to the parent ligand (Mox) having IC50 = 183.25 ± 2.06 μg/mL. These results reflect that after conjugation of Mox with Ag, the activity of moxifloxacin was significantly increased about 250 times. However, the urease inhibition activity of the Au conjugated counterpart of moxifloxacin decreased significantly. The synthesized metallic nano-conjugates (Ag-Cip and Au-Cip NPs) and the parent ligand, ciprofloxacin were also tested for jack bean urease enzyme inhibition potential. Ag-Cip pronanomedicine exhibited better urease enzyme inhibition indicating 96 % at 0.2 mg/ mL (IC50 = 1.181 ± 0.02 μg/mL) concentration. On the other hand, Au-Cip NPs showed comparatively weaker urease inhibition (90 % at 0.2 mg/mL concentration) with IC50 = 52.55±2.3 μg/mL. As anticipated, the parent ligand ciprofloxacin revealed weaker inhibition to the values of 75 % at 0.2 mg/mL and IC50 = 82.95 ±1.62 μg/mL concentrations. Furthermore, leishmanicidal, antimicrobial and antioxidant activities were tested for both synthesized pronanomedicines and all the parent ligands under discussion but they revealed good to moderate activities. The selected plants namely R. arboreum, K. pinnata, E. dabia and D. elegans and their metallic NPs were also screened for jack beans urease enzyme, leishmanicidal, antimicrobial and antioxidant activities which exhibited promising activities, while D. elegans-capped NPs showed moderate activities. Convincingly, the synthesized pronanomedicines were monodispersed and revealed stability to some extent by changing pH, concentration of table salt and temperature. The silver based pronanomedicines were anticipated to be good candidate for urease inhibition and leishmanicidal potentials.