*3.5. <sup>1</sup>H-NMR Study*

For free ceftriaxone Na2CFX, the <sup>1</sup>HNMR spectrum data obtained can be summarized as follows.

At 3.368 [CH<sup>2</sup> of thiazine, 2H] at δ 3.489, [N-CH<sup>3</sup> of triazine, 3H] at 3.889, [=N-O-CH3, 3H] at 3.960 [S-methylen, 2H], at 5.069 [β-lactam, 1H] and 6.910 [thiazol ring, 1H]. The spectra of proton nuclear magnetic resonance for [Mg(CFX)(H2O)2]·4H2O, [Zn(CFX) (H2O)2]·6H2O and [Se(CFX)Cl2]·4H2O complexes in Table 4 show occurrences of upward shifts of the field in the reading signals for Na2CFX, confirming the coordination between Mg (II), Zn (II) and Se (VI) metal ions and ceftriaxone ligand. Based on C, H and N, molar conductance, IR, <sup>1</sup>HNMR, electronic spectra and magnetic analyses, the suggested structures for ceftriaxone complexes are shown in Figure 4.


**Table 4.** HNMR spectral assignments of ceftriaxone and its complexes.

**Figure 4.** The structure of the prepared CFX complexes. (**a**) M = Mg, Cu and Zn/ CFX, n = 4,3 and 6 respectively. (**b**) Fe/CFX complex. (**c**) Se /CFX complex. **Figure 4.** The structure of the prepared CFX complexes. (**a**) M = Mg, Cu and Zn/CFX, n = 4,3 and 6 respectively. (**b**) Fe/CFX complex. (**c**) Se/CFX complex.

spectra of proton nuclear magnetic resonance for [Mg(CFX)(H2O)2]·4H2O, [Zn(CFX) (H2O)2]·6H2O and [Se(CFX)Cl2]·4H2O complexes in Table 4 show occurrences of upward shifts of the field in the reading signals for Na2CFX, confirming the coordination between Mg (II), Zn (II) and Se (VI) metal ions and ceftriaxone ligand. Based on C, H and N, molar conductance, IR, 1HNMR, electronic spectra and magnetic analyses, the suggested

**Signals Na2CFX Ligand Mg (II) Zn (II) Se (VI)** 

[2H, CH2 of thiazine] 3.368 3.352 3.342 3.318 [3H, N-CH3 of triazine ring] 3.489 3.375 3.312 3.254 [3H, =N-O-CH3] 3.889 3.879 3.785 3.547 [2H, S-CH2] 3. 960 3.864 3.687 3.758 [1H, β-lactam] 5.069 4.652 4.758 4.989 [1H, of thiazol ring] 6.910 6.897 6.874 6.987

structures for ceftriaxone complexes are shown in Figure 4.

**Table 4.** HNMR spectral assignments of ceftriaxone and its complexes.

#### *3.6. XRD Analysis 3.6. XRD Analysis*

**Table 5.** XRD analysis data.

XRD analysis is an essential technique for identifying the nature of crystallinity in metal complexes. The patterns of X-ray diffraction powder for [Zn(CFX)(H2O)2]·6H2O, [Cu(CFX)(H2O)2]·3H2O, [Fe(CFX)(H2O)2]·5H2O and [Se (CFX) Cl2]·4H2O complexes were characterized at room temperature using X-ray diffraction by Cu Kα radiation and are shown in Table 5. The X-ray diffraction patterns for Zn (II), Cu (II), Fe (III) and Se (VI) XRD analysis is an essential technique for identifying the nature of crystallinity in metal complexes. The patterns of X-ray diffraction powder for [Zn(CFX)(H2O)2]·6H2O, [Cu(CFX)(H2O)2]·3H2O, [Fe(CFX)(H2O)2]·5H2O and [Se(CFX)Cl2]·4H2O complexes were characterized at room temperature using X-ray diffraction by Cu Kα radiation and are shown in Table 5. The X-ray diffraction patterns for Zn (II), Cu (II), Fe (III) and Se (VI) CFX

CFX complexes were measured in the range of 2θ = 10–70° and are shown in Figure 5, and they have an amorphous behavior with a nano-form structure, as shown in Figure 5.

**Compound Pos. [2Th.] Height [cts] FWHM [2Th.] d-spacing [Å] Rel. Int. [%]**  Zn (II) 22.7560 169.85 0.1279 3.90457 100.00 Cu (II) 31.8381 32.61 0.1092 2.80845 100.00 Fe (III) 19.767 40.99 0.1535 4.48754 100.00 Se (IV) 19.7678 40.99 0.1535 2.80542 100.00

complexes were measured in the range of 2θ = 10–70◦ and are shown in Figure 5, and they have an amorphous behavior with a nano-form structure, as shown in Figure 5. Depending on the Scherrer relationship, the sizes of particles were detected [39] with the help of the full width at half maximum (FWHM) and have a 15–57 nm range.


**Table 5.** XRD analysis data.

**Figure 5.** XRD for (**A**): [Zn (CFX) (H2O)2]·6H2O; (**B**): [Cu (CFX) (H2O)2]·3H2O; (**C**); [Fe(CFX)(H2O)2]·5H2O (**D**) [Se (CFX) Cl2]·4H2O. **Figure 5.** XRD for (**A**): [Zn(CFX)(H2O)<sup>2</sup> ]·6H2O; (**B**): [Cu(CFX)(H2O)<sup>2</sup> ]·3H2O; (**C**): [Fe(CFX)(H2O)<sup>2</sup> ]·5H2O; (**D**): [Se(CFX)Cl<sup>2</sup> ]·4H2O.

#### *3.7. SEM and TEM Investigations*

*3.7. SEM and TEM Investigations*  TEM and SEM tools are essential techniques for identifying the surface morphology of synthesized metal complexes. Images of SEM for ceftriaxone metal complexes are shown in Figure 6. SEM images show homogeneity and uniform aggregation of Mg (II), TEM and SEM tools are essential techniques for identifying the surface morphology of synthesized metal complexes. Images of SEM for ceftriaxone metal complexes are shown in Figure 6. SEM images show homogeneity and uniform aggregation of Mg (II), Cu (II), Fe (III), Zn (II) and Se (VI) CFX complexes.

Cu (II), Fe (III), Zn (II) and Se (VI) CFX complexes.

**Figure 6.** *Cont*.

**Figure 6.** SEM (**A1**,**A2**) Mg, (**B1**,**B2**) Cu, (**C1**,**C2**) Fe, (**D1**,**D2**) Se and (**E1**,**E2**) Zn CFX complexes. **Figure 6.** SEM (**A1**,**A2**) Mg, (**B1**,**B2**) Cu, (**C1**,**C2**) Fe, (**D1**,**D2**) Se and (**E1**,**E2**) Zn CFX complexes.

Images of TEM for [Mg(CFX)(H2O)2]·4H2O, [Cu(CFX)(H2O)2]·3H2O, [Fe(CFX)(H2O)2]·5H2O, [Zn(CFX)(H2O)2]·4H2O and [Se(CFX)Cl2]·4H2O complexes are shown in Figure 7 and refer to the formation of spherical black spots with nanoparticles in the ranges of 33–57 nm, 16.18–35.91 nm, 15.03–26.87 nm, 22.83–26.87 nm and 16.09–55.63 nm, respectively. The nano-sized CFX metal complexes were observed with TEM to have a particle size of 15.03−57 nm, which is in agreement with XRD data. Images of TEM for [Mg(CFX)(H2O)2]·4H2O, [Cu(CFX)(H2O)2]·3H2O, [Fe(CFX) (H2O)2]·5H2O, [Zn(CFX)(H2O)2]·4H2O and [Se(CFX)Cl2]·4H2O complexes are shown in Figure 7 and refer to the formation of spherical black spots with nanoparticles in the ranges of 33–57 nm, 16.18–35.91 nm, 15.03–26.87 nm, 22.83–26.87 nm and 16.09–55.63 nm, respectively. The nano-sized CFX metal complexes were observed with TEM to have a particle size of 15.03–57 nm, which is in agreement with XRD data.

**Figure 7.** TEM (**A**) Cu, (**B**) Mg, (**C**) Fe, (**D**) Zn and (**E**) Se CFX complexes. **Figure 7.** TEM (**A**) Cu, (**B**) Mg, (**C**) Fe, (**D**) Zn and (**E**) Se CFX complexes.
