Fempn

3. Results and Discussion

3.1. Biosynthesis and Characterization of FeMPn

The addition of the M. pruriens seed extract to ferric (III) chloride solution produced an instantaneous colour change in the solution from brown to intense black, indicating the formation of magnetite nanoparticles. The process of the formation of FeMPn suspension occurred when the solution had been supersaturated which triggered the formation of the sol and formed magnetite nanoparticles.

The SEM images (Fig. 2) showed that FeMPn has a non-homogeneous and uneven surface, as well as the size of FeMPn that tended to vary due to aggregation. However, based on TEM image (Fig. 3), FeMPn has spherical in shape with the smallest particle of 30.5 nm. A non-homogeneous of

pruriens seed extract and FeMPn were characterized with FTIR to determine the biomolecules contained in the extract that involved in the reaction to form FeMPn. The FTIR spectra of the extract and FeMPn are shown in Fig. 5. The FTIR spectrum of the extract showed a broad absorption band in an absorbance area of 3384.8 cm-1 that assigned to the overlapping of O-H stretching vibration of flavonoids, alkaloids, polyphenols, alcohols or water and N-H stretching vibration of amine compounds, due to the hydrogen bonding. The absorption band at 1627.8 cm-1 referred to C=C stretching vibration which is possible to be derived from aromatic ring in amino acid, while the absorption band in 1529.4 cm-1 referred to N-H bending vibration of amine which is possible to be derived from the L-dopa. An intense enough absorption band at absorbance area of 1400.2 cm-1 referred to C-H bending vibration of sp2 carbon, which is possible to be derived from the aromatic ring of amino acid. The weaker absorption band at 1288.4 cm-1 corresponded to =C-O stretching vibration of aromatic compounds, and the absorption band at 1074.3-1118.6 cm-1 referred to C-O stretching vibration of amino

The mass reduction at 140 ºC and an endothermic peak at 123.8 ºC on the TGA/DTA curve of the extract assigned to the evaporation of water, while on FeMPn the mass reduction observed under 100 ºC and an endothermic peak emerged at 96.17 ºC. The mass reduction and endothermic peaks also emerged at 200-300 ºC and above 300 ºC on the TGA/DTA curve of the extract and FeMPn respectively indicated the evaporation of some organic molecules. The broad exothermic peak at 280 ºC on the TGA/DTA curve of FeMPn indicated the bond breaking of L-dopa with magnetite nanoparticles. At a temperature of 550 ºC, the total mass of the extract remained was 38.37%, while it was 48.70% for FeMPn. From these results, it could be concluded that the addition of Fe to the extract impacted on the thermal stability that made FeMPn has a better thermal stability than the extract