Optimization of photocatalytic degradation of meloxicam using titanium
dioxide nanoparticles: Application to pharmaceutical waste water analysis,
treatment and cleaning validation
Ahmed H. Nadima, Medhat A. Al-Ghobashya,b,*, Marianne Nebsenc and Mostafa A. Shehataa
a
Analytical Chemistry Department, Faculty of Pharmacy, Cairo University, Egypt
b
Bioanalysis Research Group, Faculty of Pharmacy, Cairo University, Egypt
c
Pharmaceutical Chemistry Department, Faculty of Pharmacy and Drug Technology, Heliopolis University, Egypt
*
Correspondence:
Dr. Medhat A. Al-Ghobashy, Analytical Chemistry Department, Faculty of Pharmacy, Cairo
University, Cairo 11562, Egypt
E-mail: medhat.alghobashy@cu.edu.eg
1
Supplementary materials
Figure S1: CZE electropherogram (A) of MELO degraded sample (250.00 μg/mL) after UV light
irradiation (254 nm, 1012 μW/cm2) at pH 9.0 for 30 h showing the spectral purity plot of MELO
peak (B)
2
Figure S2: HPLC chromatogram showing the result of photodegradation of MELO (500.00
μg/mL) upon exposure to UV light (1012 μW/cm2) at pH 9.0 for 30 h (A) in the absence of
TiO2NP and (B) in the presence of 0.8 mg/mL TiO2 NP
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Figure S3: Main effects plot for % MELO photodegradartion showing the effect of: (A)
irradiation time, (B) UV light intensity and (C) initial MELO concentration.
Figure S4: Normal probability plot of the residuals for MELO photodegradation.
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Figure S5: Kinetic profile of the photodegradation of 250.00 µg/mL initial MELO concentration
at pH 9 with 0.4 mg/mL TiO2 NP under UV irradiance of 1012 µw/cm2 (a) chemical analysis
achieved by RP-HPLC and (b) chemical analysis achieved by CZE.
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Table S1: Analysis of variance for photocatalytic degradation of MELO
Source of
Degree of
Sum of
Mean of
variation
freedom
squares
squares
Main effects
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699.37
pH
1
Irradiation time
F value
P Value
139.874
16.11
0.001
26.37
26.368
3.04
0.120
1
222.16
222.159
25.58
0.001
Light intensity
1
225.15
225.150
25.93
0.001
TiO2NP loading
1
42.90
42.902
4.94
0.057
1
182.79
182.790
21.05
0.002
2
197.03
98.515
11.34
0.005
1
80.28
80.282
9.24
0.016
1
116.75
116.748
13.44
0.006
Initial MELO
concentration
2 way interactions
Irradiation time light intensity
Irradiation time Initial MELO
concentration
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