This may originate due to presence of GO which shows absorbance at higher wavelengths [25]. PL spectra of B1 show a peak at 500nm (λex = 250nm), typical PL emission of Compound Library clinical trial carbon nanomaterials including C-dots. PL is unique attribute of quantum confinement as in case of C-dots. Moreover, in case of C-dots including GQDs,

excitation dependent emission wavelength (λem) is also a signature marker, as elucidated by earlier research Inhibitors,research,lifescience,medical [23]. Figure 2 UV-Vis Spectroscopy of separated bands (i, ii, and iii) showing signature absorbance of C-dots. Inset shows PL spectra of corresponding bands (λex = 250nm). Right panel displays SEM image (bi and bii) and HRTEM image (biii) of bands i, … A typical X-Ray diffraction (XRD) (Figure 3(a)) shows prominent peaks at 2θ = 25.67° and a feeble peak at 2θ = 42.17° which arise due to (002) and (101) diffraction patterns which are of of graphitic carbon, respectively [26] (Figure 2(b)). Raman spectra (Figure 3(b)) of B1 display feeble Raman peak of G-band observed at 1565cm−1 Inhibitors,research,lifescience,medical with respect to more intense peaks of D-band at 1303cm−1 showing presence of chaotic carbon nanomaterials in the form of C-dots [27]. Figure 3 (a) X-ray diffraction pattern and (b) Raman spectra of fraction B1 displaying signature peaks confirming presence of C-dots. Field emission scanning Inhibitors,research,lifescience,medical electron microscopy (FE-SEM) image (Figure 2(bi)) shows presence of roughly spherical

C-dots of size ~30nm. In a stark contrast to B1, B2 displayed more prominent green fluorescence blended with blue tinge due to absence of impurity and high concentration of variable sized C-dots. UV-Vis spectra show presence of a sharp peak at 235nm followed by a hump at 265nm. In comparison to B1, there was blue shift of 8nm in UV-Vis spectrum (Figure 2(a)), indicating the reduction Inhibitors,research,lifescience,medical in size of C-dots [28]. Moreover, reductions in intensity of the peak as well as the background also suggest relative purity of B2 with respect to B1. PL spectrum (λex = 250nm) shows peak at 472nm, slight blue shift of 8nm with respect to B1. As

per earlier studies PL at lower wavelength indicates C-dots of smaller dimensions Inhibitors,research,lifescience,medical [29]. All the other features of B2 such as XRD pattern and Raman spectra were very much similar to B1; hence this data (-)-p-Bromotetramisole Oxalate is not shown. SEM image (Figure 2(bii)) shows clear reduction in size to ~10nm. B3 was light grey color under ambient light and blue under UV light (Figure 1). Blue color displays ultrasmall size [25] as evident from high resolution transmission electron microscopy (HRTEM) image (Figure 2(biii)) showing nanoparticles of size ~7nm. UV-Vis spectrum (Figure 2(a)) shows deeper UV absorption at 232nm and a short trail at 263nm. There was further blue shift of 3nm due to reduction in size as evident from HRTEM. PL spectrum shows diminished intensity followed by a peak at 463nm. In order to further purify C-dots for ferrying ciprofloxacin, B3 was dialyzed against nanopure water for 12h.