Abstract The evolution of nanotechnology and the production of nanomedicine from various
sources had proven to be of intense value in the field of biomedicine. The smaller size of nanoparticles
is gaining importance in research for the treatment of various diseases. Moreover the production
of nanoparticles is eco-friendly and cost effective. In the present study silver nanoparticles were
synthesized from Carica papaya leaf extract (CPL) and characterized for their size and shape using
scanning electron microscopy and transmission electron microscopy, respectively. Fourier
transform infrared spectroscopy (FTIR), Energy dispersive X-ray spectroscopy (EDS/EDX) and
X-ray diffraction spectroscopy (XRD) were conducted to determine the concentration of metal
ions, the shape of molecules. The bactericidal activity was evaluated using Luria Bertani broth
cultures and the minimum inhibition concentration (MIC) and minimum bactericidal concentration
(MBC) were estimated using turbidimetry. The data analysis showed size of 50–250 nm spherical
shaped nanoparticles. The turbidimetry analysis showed MIC and MBC was >25 lg/mL against
both Gram positive and Gram negative bacteria in Luria Bertani broth cultures. In summary the
synthesized silver nanoparticles from CPL showed acceptable size and shape of nanoparticles
and effective bactericidal activity