Cetyltrimethylammonium bromide-gold nanoparticles composite modified pencil graphite electrode for the electrochemical investigation of cefixime present in pharmaceutical formulations and biology

Cetyltrimethylammonium bromide-gold nanoparticles composite modified pencil graphite electrode for the electrochemical investigation of cefixime present in pharmaceutical formulations and biology

Chemical Data Collections 21 (2019) 100217 Contents lists available at ScienceDirect Chemical Data Collections journal homepage: www.elsevier.com/lo...

NAN Sizes 0 Downloads 0 Views

Chemical Data Collections 21 (2019) 100217

Contents lists available at ScienceDirect

Chemical Data Collections journal homepage: www.elsevier.com/locate/cdc

Data Article

Cetyltrimethylammonium bromide-gold nanoparticles composite modified pencil graphite electrode for the electrochemical investigation of cefixime present in pharmaceutical formulations and biology P. Manjunatha, Y. Arthoba Nayaka∗ Department of Chemistry, School of chemical science, Kuvempu University, Jnanasahyadri, Shankaraghatta-577 451, Shivamogga, Karnataka, India

a r t i c l e

i n f o

a b s t r a c t

Article history: Received 15 September 2018 Revised 24 March 2019 Accepted 25 March 2019 Available online 26 March 2019

Cefixime is served as an important class of antibiotics for the treatment of infectious diseases in both human and animals. This is extensively used in the clinical practice and therapy to safeguard human health. The widespread use of cefixime and the need for pharmacological studies necessitates the development of fast, sensitive and accurate analytical technique/s to assay the presence of drug. In the present work, a novel and cost-effective electrochemical sensor has been developed for the electrochemical investigation of cefixime. The SEM, CV and EIS were used for electrodes characterization. At CTAB/AuNPs/PGE the oxidation of cefixime was found to be irreversible and diffusion-controlled. The linearity was established in the range of 10 × 10−9 to 30 × 10−8 M with detection limit of 1.21 × 10−10 M. The applicability of the proposed electrochemical sensor has been successfully illustrated by the estimation of cefixime present in pharmaceutical formulations and biological fluids. © 2019 Elsevier B.V. All rights reserved.

Keywords: Cefixime Cetyltrimethylammonium bromide Cyclic Voltammetry Differential pulse voltammetry Gold nanoparticles Pencil graphite electrode

Specifications Table Subject area Compounds Data category Data acquisition format Data type Procedure Data accessibility

Physical Chemistry and Analytical Chemistry Cefixime Spectral, Electrochemical Voltammograms, SEM, UV-visible, characterization of the data Analyzed Novel CTAB/AuNPs/PGE has been fabricated, characterized and applied for the electrochemical investigation of cefixime present in synthetic and real samples. Data is with this article

1. Rationale Cefixime is an effective antibiotic against some group of organisms such as Staphylococcus pneumoniae, Haemophilus influenzae, Escherichia coli, Neisseria gonorrhoeae and Steptococcus pyogenes. It is used for the treatment of susceptible bacterial



Corresponding author. E-mail address: [email protected] (Y.A. Nayaka).

https://doi.org/10.1016/j.cdc.2019.100217 2405-8300/© 2019 Elsevier B.V. All rights reserved.

2

P. Manjunatha and Y.A. Nayaka / Chemical Data Collections 21 (2019) 100217

S

O H

H2N

N H

N N

O

H

S

N

CH2

O COOH

COOH

Scheme 1. Chemical structure of cefixime.

infections of middle ear, tonsillitis, otitis media, pharyngitis throat infections, laryngitis, bronchitis, urinary tract infections, gonorrhoea pneumonia etc. [1–5]. From decades, cefixime is served as an important class of antibiotics for the treatment of infectious diseases in both human and animals. In addition, the extensive use of cefixime in veterinary medicine as antibiotics and growth accumulation promoters has led to their accumulation in diary food products, such as meat, milk, honey, eggs and found to cause serious threats to human health. To safeguard human health, the European Union has set safe residue limits for residues of veterinary drugs in animal tissues entering the human food chain [6–8]. The widespread use of cefixime and the need for clinical and pharmacological study requires fast, sensitive and accurate analytical technique/s to assay the presence of drug/s present in pharmaceuticals and biological samples [9]. Presently, the cefixime is extensively used in the clinical practice and therapy. Hence, development of suitable analytical method for rapid and routine analysis of cefixime present in artificial and real samples is having considerable importance. The various methods have been reported for the determination of cefixime such as fluorimetry [10,11], high performance liquid chromatographic-electrospray ionization mass spectrometry [12–14], high performance liquid chromatography [15], high performance thin layer chromatography [16], voltammetry [17–19] and liquid chromatography (LC)–tandem mass spectrometry [20]. However, these methods have several disadvantages such as high-cost, long analysis time, lengthy procedures, need for derivatization etc. not feasible for routine analyses [21]. Thus, recently electrochemical techniques are becoming significant alternatives for the determination of biologically important molecules [22]. The electroanalytical methods have been established a considerable attention for the determination of organic molecules including drugs and related molecules such as cephalosporins in dosage forms and biological fluids [23,24]. These methods are low-cost and having great applications in medicine, environmental monitoring and industrial processes etc. [25–28]. Typically, in these techniques the outcome of the analysis are depends on the sensors used and their physico-chemical properties and also the operation mechanism of such modified electrodes depends on the properties of the modifier material/s [29]. Hence, the modifications of electrodes via suitable modifier/s are always plays a vital role [30–32]. Recently, to improve the electrochemical performances of the modified electrodes, different kinds of nanomaterials have been applied for electrode modifications due to their increased surface area, chemical, optical, electrical and adsorption properties [33]. The review of literature reveals that various nanomaterials have been reported for selective, sensitive and online determination of toxic compounds, biomolecules and drugs [34]. Among various nanomaterials, AuNPs are significantly used for electrode modifications in the fabrication of sensors/biosensors [35]. In addition, the nano-sized AuNPs can enhance the electrode conductivity, the rate of electron transfer and the analytical sensitivity [36]. However, the electrocatalytic properties of AuNPs depend on the size, shape and supporting materials [37]. To the best of our knowledge there were no reports available for the determination of cefixime using drop casted/codeposited cetyl-trimethyl ammonium bromide goldnanoparticles modified pencil graphite electrode (CTAB/AuNPs/PGE) (Scheme 1). Therefore, in the present work the modification of pencil graphite electrode (PGE) using gold nanoparticles (AuNPs) and cetyltrimethyl ammonium bromide (CTAB) has been made for the estimation of cefixime in the pharmaceutical formulations and biological samples.

2. Experimental procedures 2.1. Instrumentations The electrochemical workstation (CHI660D, CH Instruments, USA) with standard three-electrode assembly are used for all the electrochemical measurements. Here, pencil graphite electrode (PGE) or cetyltrimethyl ammonium bromide-gold nanoparticles modified pencil graphite electrode (CTAB/AuNPs/PGE), platinum wire and Ag/AgCl were respectively used as working, auxiliary and reference electrode. The UV-Vis spectroscopic analysis were performed using UV-Vis spectrophotometer (Model: USB 40 0 0, Ocean Optics, USA) and the surface morphology of electrodes were obtained by field emission scanning electron microscope (Model: VEGA3 TESCAN, India).

P. Manjunatha and Y.A. Nayaka / Chemical Data Collections 21 (2019) 100217

3

2.2. Chemicals and reagents Cefixime is purchased from Sigma-Aldrich, India and used as received without purification. A stock solution of 1 mM cefixime was prepared in phosphate buffer solution (PBS) of pH 7.0. The tablets containing cefixime content such as Topcef-100 and Qceph-200 were purchased from local pharmaceutical shops, Shivamogga, Karnataka, India. The chloroauric acid, cetyltrimethyl ammonium bromide, potassium di-hydrogen phosphate (KH2 PO4 ) and di-potassium hydrogen phosphate (K2 HPO4 ) were procured from Merck, Mumbai, India. Potassium ferricyanide (K3 [Fe(CN)6 ]) was procured from Merck, Darmstadt, Germany and all the chemicals used were of analytical grade. The 0.2 M PBS was prepared and used as analytical medium. The pH of the solution was adjusted either by using H3 PO4 or NaOH for acidic or basic pH and all the reagents were prepared by using double distilled water. 2.3. Preparation of unmodified and modified electrodes The PGE and AuNPS/PGEs are prepared according to the earlier works reported [38,39]. The CTAB solution (10 mg/10 mL) was drop casted on a surface of AuNPs/PGE. Then the resulted CTAB/AuNPs/PGE was allowed to dry at room temperature for about 20–30 min. After that, the dried CTAB/AuNPs/PGE was gently washed with double distilled water to remove the loosely held CTABs on the surface of CTAB/AuNPs/PGE and the resultant modified electrode was used as working electrode for electrochemical analyses. 3. Data, value and validation 3.1. Surface morphology The SEM features of PGE, AuNPs/PGE, CTAB/PGE and CTAB/AuNPs/PGE have been studied and compared (Fig. 1A). The surface morphology of PGE appears to be smooth and contains spindle-like structures with a presence of micro cavities. The surface morphology of AuNPs/PGE (Fig. 1B) shows that AuNPs present as clusters with large number of vallyes. Fig. 1C is the surface morphology of CTAB/PGE and it shows the non-porous spindle-shaped structures. The surface morphology of CTAB/AuNPs/PGE shows close packing arrangement of CTAB with AuNPs as stacked-flakes. The formation of stacked

(A)

(B)

(C)

(D)

Fig. 1. SEM images of (A) PGE, (B) AuNPs/PGE, (C) CTAB/PGE, (D) CTAB/AuNPs-PGE.

4

P. Manjunatha and Y.A. Nayaka / Chemical Data Collections 21 (2019) 100217

Fig. 2. Illustrates the effect of CTAB concentration on anodic peak current.

flake-like structures and valleys on the surface of modified electrode increases the effective surface area and surface roughness of the electrode. Hence, the modification of electrode favours the promotion of adhesion and immobilization of analyte on the electrode surface [40]. Furthermore, the increase in surface area and the electron transfer capacity has been verified by the electrochemical studies of potassium ferricyanide (K3 [Fe(CN)6 ]).

3.2. Influence of modifier concentration (CTAB) The influence of the modifier concentration on the oxidation peak current has been investigated using 1 mM cefixime in 0.2 M PBS of pH 7.0 at a scan rate of 100 mV s − 1 (Fig. 2). In the present study, various amounts of CTAB (i.e. 2.5 mg, 5.0 mg, 7.5 mg, 10 mg, 12.5 mg and 15 mg) were dissolved separately in 10 mL distilled water and drop casted on the surface of AuNPs/PGE. From Fig. 2, it can be noticed that, with increase in the concentration of CTAB improved the electrochemical response up to the concentration of 10 mg of CTAB dissolved in 10 mL of distilled water. On further increase in the concentration of CTAB, the electrochemical performance of the modified electrode has been decreased with a subsequent decrease in the electron transfer rate and is attributed to the formation of compact layer of CTAB on the electrode surface. Therefore, based on the above observations, the 10 mg concentration of CTAB solution was selected as the optimized concentration for the electrochemical determination of cefixime.

3.3. Electrochemical characterizations The electrochemical response of K3 [Fe(CN)6 ] at (a) PGE, (b) CTAB/PGE, (c) AuNPs/PGE and (d) CTAB/AuNPs/PGE were recorded (Fig. 3A). The CV of (a) PGE, (b) CTAB/PGE, (c) AuNPs/PGE and (d) CTAB/AuNPs/PGE showed a peak-to-peak potential separation (Ep ) of 0.191 V, 0.126 V, 0.075 V and 0.072 V respectively. From Fig. 3A it is evident that K3 [Fe(CN)6 ] exhibited a poor electrochemical behaviour on PGE, with a high capacitive background current, large peak-to-peak potential separation (Ep ) and broadened wave shape. Further, the CTAB/PGE and AuNPs/PGE showed a little improvement in the electrochemical response of K3 [Fe(CN)6 ] with an increase in the magnitude of peak current but, they showed broadened peak shapes and overpotential. However, at CTAB/AuNPs/PGE showed a significant improvement in the electrochemical performances. Therefore, reduction in the value of Ep with a subsequent increase in the magnitude of peak current clearly indicated that better reversible charge transfer process at CTAB/AuNPs/PGE [41,42]. In order to determine the active surface area (A) of the electrode, the voltammograms of 1 mM K3 [Fe(CN)6 ] in 0.1 M KCl at different scan rates at unmodified and modified electrodes were recorded and used for the calculations. For the reversible electrode processes, the following Randles-Sevcik equation [43] can be applied.





i p = 2.69 × 105 n3/2 ADo1/2 υ 1/2 where, ip = anodic current in μA, n = number of electrons transferred, A = electroactive surface area in cm2 , Do = diffusion coefficient in cm2 s − 1 , υ = scan rate in V s − 1 and Co∗ = concentration of K3 [Fe(CN)6 ]. Here, 1 mM K3 [Fe(CN)6 ] in 0.1 M KCl is

P. Manjunatha and Y.A. Nayaka / Chemical Data Collections 21 (2019) 100217

5

Fig. 3. (A) Illustrate the CVs of 5 mM K3 [Fe(CN)6 ] in 0.1 M KCl at (a) PGE, (b) CTAB/PGE, (c) AuNPs/PGE and (d) CTAB/AuNPs/PGE at a scan rate of 100 mV s − 1 . (B) EIS at (a) PGE, (b) AuNPs/PGE, (c) CTAB/PGE and (d) CTAB/AuNPs/PGE in 0.1 M KCl solution containing 5 mM K3 [Fe(CN)6 ] with a frequency range: 10 kHz–0.1 Hz. Inset: Randle’s equivalent circuit.

a reversible electrode process and hence, n = 1 and Do = 7.6 × 10−6 cm2 s − 1 . By considering the slope of the plot ipa vs. υ 1/2 , the active surface areas of PGE, AuNPs/PGE, CTAB/PGE and CTAB/AuNPs/PGE have been calculated and found to be 0.00845 cm2 , 0.01089 cm2 , 0.01151 cm2 and 0.02625 cm2 , respectively. The EIS of CTAB/AuNPs/PGE has been compared to that of AuNPs/PGE, CTAB/PGE and PGE by EIS technique (Fig. 3B). The impedance data obtained for PGE, AuNPs/PGE, CTAB/PGE and CTAB/AuNPs/PGE for 5 mM K3 [Fe(CN)6 ] in 0.1 M KCl solution were fitted using the electrochemical equivalent circuit (EEC) and is given in the inset of Fig. 3B. The charge transfer resistance values (Rct ) for PGE, AuNPs/PGE, CTAB/PGE and CTAB/AuNPs/PGE were found to be 1082 kΩ, 703.3 kΩ 691.6 kΩ and 306.1 kΩ respectively. From Fig. 3B, it is evident that the impedance graphs obtained for PGE, AuNPs/PGE and CTAB/PGE have got higher Rct values compare to that of CTAB/AuNPs/PGE. These results clearly indicated the better conductivity of CTAB/AuNPs/PGE, which is ascribed to the increased charge transfer rate at the surface adsorbed CTAB/AuNPs [44,45]. 3.4. Effect of pH The influence of solution pH on the oxidation peak current (ipa ) and oxidation peak potential (Ep ) of cefixime has been studied at CTAB/AuNPs/PGE by varying the solution pH from 4.0 − 8.0 (Fig. 4A). The results showed that cefixime exhibits a highest peak current at pH 7.0 and it has been decreased with increase in solution pH above 7.0. Thus, pH 7.0 has been selected as a suitable analytical medium for the electrochemical investigation of cefixime [46]. On the other hand, the solution pH influences on oxidation peak potential that, it has been shifted to a less positive value as solution pH increases

6

P. Manjunatha and Y.A. Nayaka / Chemical Data Collections 21 (2019) 100217

Fig. 4. (A) Illustrates the effect of pH (4.0, 5.0, 6.0, 7.0 and 8.0) on peak current of cefixime (20 μM) at CTAB/AuNPs/PGE in 0.2 M PBS of various pH solutions; (B) Illustrates the effect of pH on the peak potential of cefixime (20 μM) at CTAB/AuNPs/PGE in 0.2 M different PBS of various pH solutions.

from 4.0 to 9.0 (Fig. 4B). The interaction can be explained based on the variation in the protonation of acid-base functions in the molecule [47,48]. The corresponding regression equation can be expressed as: Ep (V) = 0.9924 −0.046 pH; R = 0.99832. In order to substantiate the percentage of deviation of Ep values from linearity, the error bars have been included and the deviation is found to be well within 1.4%. The slope value of 46 mV/pH illustrates the involvement of identical number of protons and electrons in the electrode processes [49]. 3.5. Electrochemical studies The electrochemical performances of 1 mM cefixime prepared in PBS of pH 7.0 at PGE, AuNPs/PGE, CTAB/PGE and CTAB/AuNPs/PGE have been investigated by CV (Fig. 5A). It can be noticed that, cefixime gave irreversible oxidation peak at PGE, AuNPs/PGE, CTAB/PGE, and CTAB/AuNPs/PGE in the applied potential range of 0.4 V to 1.0 V. A well-defined irreversible oxidation peak can be noticed at CTAB/AuNPs/PGE vs. Ag/AgCl. At PGE, the cefixime exhibited a poor, broad and irreversible oxidation peak at +0.93 V, which might be ascribed to the low electrical conductivity and low surface area of PGE. The cefixime at AuNPs/PGE and CTAB/PGE exhibited relatively better oxidation peak current compare to PGE, but not considerable decrease in the overpotentials and peak shapes become broadened. Hence, to ascertain better electrochemical performances the electrodes are further modified using CTAB and noticed the better electrochemical performances of CTAB/AuNPs/PGE towards the determination of cefixime. It is attributed to the enhanced surface area, increased conductivity and facilitated the electron transfer between the analyte and the electrode surface. However, during successive voltammograms (Fig. 5B) there is a decrease in the oxidation peak current with increase in the number of cycles which could attributed to the saturation of active surface area of the electrode [50,51]. Hence, CVs corresponds to the first cycle was recorded for further studies.

P. Manjunatha and Y.A. Nayaka / Chemical Data Collections 21 (2019) 100217

7

Fig. 5. (A) Illustrate the CVs of PBS of pH 7.0 at (a) CTAB/AuNPs-PGE, 1 mM cefixime at (b) PGE, (c) AuNPs/PGE (d) CTAB/PGE and (e) CTAB/AuNPs/PGE in 0.2 M PBS of pH 7.0 at a scan rate of 100 mV s − 1 ; (B) Depicts the successive CVs (5 cycles) of 1 mM cefixime at CTAB/AuNPs/PGE in 0.2 M PBS of pH 7.0 at a scan rate of 100 mV s − 1 .

3.6. Influence of potential scan rate The nature of electrode processes and influence of potential scan rate (υ ) on peak current (ip ) of cefixime at CTAB/AuNPs/PGE have been studied by CV (Fig. 6A). It was noticed that the anodic peak currents were increased linearly and potentials shifted towards more positive values as the υ increases from 100 mV s − 1 to 250 mV s − 1 , indicating the diffusion-controlled electrode process. Correspondingly, the plot of square root of scan rate (υ 1/2 ) vs. anodic peaks currents (ipa ) showed a linear relationship (Fig. 6B), substantiates that cefixime exhibits diffusion-controlled oxidation process at CTAB/AuNPs/PGE [52]. The corresponding linear equation can be expressed as: ipa (μA) = 4.594υ 1/2 − 10.661; R = 0.99287. In order to substantiate the percentage of deviation of ‘ipa ’ values from linearity, the error bars have been included and the deviation is well within 2.5%. The relationship between logipa vs. logυ is plotted and noticed the linearity, the corresponding linear equation can be expressed as: logipa = 0.632 log υ + (− 0.719); R = 0.99736. The slope value of 0.632 is close to the theoretical value of 0.5, which clearly indicates that the cefixime exhibits diffusion-controlled electrode process at CTAB/AuNPs/PGE [53]. Similarly, the plot of anodic peak potentials (Epa ) and logυ illustrates that as the υ increases Epa shifted to more positive values, and a linear relationship was established in the potential range from 100 mV s − 1 to 250 mV s − 1 (Fig. 6C). The corresponding linear regression equation was expressed as: Epa = 0.06299logυ + 0.64076; R = 0.99615. In order to substantiate the percentage of deviation of Epa values from linearity, the error bars have been included and the deviation is well within 0.5%.

8

P. Manjunatha and Y.A. Nayaka / Chemical Data Collections 21 (2019) 100217

Fig. 6. (A) Illustrates the CVs of 1 mM cefixime at CTAB/AuNPs/PGE in 0.2 M phosphate buffer solution of pH 7.0 at various scan rate of (a) 100, (b) 125, (c) 150, (d) 175, (e) 200, (f) 250 mV s − 1 ; (B) Illustrates the relationship between anodic peak currents with square root of scan rate; (C) Illustrates the relationship between the anodic peak potentials with logarithmic scan rate.

According to Laviron [54], the transfer coefficient ‘α ’, and the apparent heterogeneous charge transfer rate constant ‘k0 ’ can be estimated using the plot Epa vs. logυ . Here, the ‘α ’ was estimated to be 0.5 and therefore, k0 was determined using the following equation [55].

Ep = E0 +

 2.303RT  α nF



log

RT k0 α nF



+

 2.303RT  α nF

log υ

Here, E0 is the formal potential, the value of α n can be calculated from the slope of Epa vs. logυ and it is calculated to be 0.9387. For irreversible electrodes process, the value of ‘α ’ to be taken as 0.5 and hence the number of electrons transferred (n) in the electro-oxidation of cefixime has been calculated and found to be 2. The value of E° can be determined from the intercept of the plot Epa vs. logυ by extrapolating to the vertical axis at υ = 0 [56]. In the present system, the intercept of plot of Epa vs. logυ is found to be 0.64076. Therefore, the ‘k0 ’ for the electro oxidation of cefixime was calculated and found to be 1.71533 s − 1 . 3.7. Validation of the developed method 3.7.1. Linearity The influence of cefixime concentration (C) on ipa has been studied at CTAB/AuNPs/PGE. The ipa of cefixime at CTAB/AuNPs/PEG was found to be increased linearly with increase in the concentration of cefixime (Fig. 7A). The linearity has been established in the concentration range of 10 × 10−9 to 30 × 10−8 M (Fig. 7B). In order to substantiate the percentage of deviation from linearity, the error bars have been included and the deviation is well within 1.0%. The corresponding linear regression equation can be expressed as: ipa = 7.57919 × 10−10 C + 1.91081 × 10−7 ; R = 0.99816. 3.7.2. Limit of detection (LOD) LOD was estimated by the equation:

LOD = 3.3 S/m where, S is the standard deviation of the intercept and m is the slope of the regression line of the plot ipa vs. C. The calculated LOD for cefixime was found to be 1.21 × 10−10 M, which is comparable with the LODs reported in the literature.

P. Manjunatha and Y.A. Nayaka / Chemical Data Collections 21 (2019) 100217

9

Fig. 7. (A) Illustrates the DPVs of cefixime at CTAB/AuNPs/PGE in the range between 10 × 10−9 M to 30 × 10−8 M (a to f) in PBS of pH 7.0; (B) Illustrates the relation between anodic peak current (ipa ) vs. various concentrations (C) of cefixime in 0.2 M PBS of pH 7.0.

The relative standard deviation (RSD) was also found out to be 1.5%, which significantly specifies that CTAB/AuNPs/PGE having excellent reproducibility and better analytical applicability towards the electrochemical investigation of cefixime. 3.7.3. Specificity The specificity of the modified electrodes for the determination of given analyte may affect by some of the interfering substances/excipients present in pharmaceutical and biological samples [57]. Therefore, in order to verify the specificity/selectivity of CTAB/AuNPs/PGE towards the electrochemical determination of cefixime, the oxidation of cefixime was carried out in presence of some possible interfering substances such as, ascorbic acid, uric acid, glucose, sodium and potassium. The presence of these interfering substances/excipients did not affect the oxidation potential of cefixime even if the concentrations of interfering substances are ten-fold higher than that of cefixime. This clearly indicated that, the developed CTAB/AuNPs/PGE has better efficacy towards the electrochemical determination of cefixime even in the presence of some possible interfering substances. 3.7.4. Accuracy and precision The accuracy and precision of the proposed method using CTAB/AuNPs/PGE has been verified. The intra-day precision of the method was evaluated by repeating five experimental measurements for fixed concentration of cefixime of 10 μM. The relative standard deviation was found to be 2.5% and during the real sample analysis, the good recovery percent was observed in the range 97.05% to 103.85%, indicating that the proposed method using the modified electrode CTAB/AuNPs/PGE has got excellent accuracy.

10

P. Manjunatha and Y.A. Nayaka / Chemical Data Collections 21 (2019) 100217 Table 1 Comparatives study table of the electrochemical performances at proposed sensor with that of various electrochemical sensors reported in the literature. Electrode type

Technique

AuNPs/MWCNTs/GCE AuNPs-screen printed gold electrode AuNPs/MWCPE NiFe2 O4 HMDE MWCNTs/GCE Pt-W/MWCNTs CTAB/AuNPs/PGE

Linear rage (mol/L)

SWV SWV SWV SWV CV Amperometry DPV

−8

−4

1.0 × 10 – 2.0 × 10 10 × 10−6 – 10 × 10−4 1.0 × 10−8 – 2.0 × 10−4 6.0 × 10−6 – 2.0 × 10−4 1.0 × 10−7 – 6.0 × 10−4 1.0 × 10− 8 − 3.2 × 10−6 10 × 10−9 − 30 × 10−8

LOD (μ mol/L)

References

−9

[2] [6] [9] [18] [58] [59] This work

3 × 10 – 3 × 10−9 64 × 10−8 90 × 10−9 5 × 10−9 1.21 × 10−10

Table 2 Determination of cefixime present in pharmaceuticals (n = 3). Samples

Detected (nM)

Spiked (nM)

Found (nM)

Recovery (%)

Topcef-100 Qceph-200

106.97 101.63

20 20

126.51 121.57

97.77 99.70

3.7.5. Robustness The robustness was evaluated by the influence of small variations of some of the important variables, including increment potential, time and pH. The results provided a reliability of the proposed method for the appraisal of cefixime and hence it can be considered as robust. The mean percentage recoveries based on an average of five replicate measurements were not significantly affected within the studied range of variations of operational parameters and consequently the proposed method can be considered as robust. 3.7.6. Ruggedness The ruggedness is defined as the degree of reproducibility of results obtained by the analysis of same sample under variety of normal test conditions such as different laboratories and different lot of reagents, under the same operational conditions at different elapsed time by two different analysts. The methods were found to be rugged with the results of variation coefficients 3.16% and 2.91% by DPV method. Therefore, the results proved no statistical differences between different analysts. 3.7.7. Comparison of present method with literature The comparison between the analytical performances of CTAB/AuNPs/PGE with previously reported various modified electrodes in the literature are tabulated in Table 1. The statistics reveals that, the CTAB/AuNPs/PGE exhibits better analytical performances when compare to other modified electrodes reported in the literature. 3.8. Analytical applications The analytical applicability of the proposed method has been illustrated by the estimate the concentration of cefixime present in pharmaceutical formulations and biological fluids via standard addition methods. 3.8.1. Analysis of pharmaceutical formulations In order to find out the concentration of cefixime, the voltammograms were recorded under the optimized experimental conditions and correlated with linear calibration curve of the plot ipa vs. C (Fig. 7B). The calculations were made using standard addition method and the results are tabulated in Table 2. The RSD for five parallel measurements were less than 2.5%. The percentage recoveries of tablets formulations are found to be 97.77 and 99.70. Thus, estimation of cefixime present in pharmaceutical formulations at CTAB/AuNPs/PGE is considered to be effective methods. 3.8.2. Determination of cefixime in serum and urine samples To verify the significance of the proposed method, cefixime present in human serum and urine samples were estimated using CTAB/AuNPs/PGE by DPV technique. The standard addition methods have been followed and the findings were tabulated in Table 3. The recovery percentages found in human serum and urine samples are found to be 97.05, 103.85 and 98.75 respectively. Therefore, the good recovery rate at CTAB/AuNPs/PGE suggests that, the proposed method for the estimation of cefixime has free from interference of sample matrix (human serum and urine samples). 4. UV-visible spectrophotometry The UV-Vis Spectrophotometry technique is one of the significant techniques for the estimation of biologically important molecules with respect to characteristic absorption spectra (λmax ) [60]. The UV-Vis spectrohotometric analysis of cefixime

P. Manjunatha and Y.A. Nayaka / Chemical Data Collections 21 (2019) 100217

11

Table 3 Determination of cefixime present in physiological samples (n = 3). Samples

Detected (nM)

Spiked (nM)

Found (nM)

Recovery (%)

Human serum sample-1 Human urine sample-1 Human urine sample-2

115.62 126.35 99.26

20 20 20

135.03 147.12 119.01

97.05 103.85 98.75

Fig. 8. UV-Vis absorption spectras of (a) standard cefixime, (b) tablet formulation (Topcef-100), (c) human urine sample-2 (d) human urine sample-1, (e) tablet formulation (Qceph-200) and (f) human serum sample in 0.1 M phosphate buffer solution of pH 7.0.

has been undertaken and confirmed the presence of cefixime present in pharmaceutical formulations such as Topcef-100, Qceph-200 and biological samples such as human serum and urine samples (Fig. 8). The λmax of standard cefixime, pharmaceutical formulations and biological samples were recorded by taking 0.2 M PBS of pH 7.0 as reference. Under optimised experimental conditions, the standard cefixime showed λmax at 287.25 nm. The Topcef-100 and Qceph-200 showed λmax at 287.25 nm and 287.24 nm respectively. Similarly, the human serum sample, human urine sample-1 and human urine sample2 showed λmax at 287.26 nm, 287.26 nm and 287.25 nm, respectively. Thus, it confirmed the presence of cefixime present in pharmaceutical formulations and biological fluids. 5. Conclusions In the present work, the novel, sensitive and low-cost drop casted CTAB/AuNPs/PGE has been developed as a convenient and reliable electrochemical sensor for the electrochemical investigation of cefixime. The CTAB/AuNPs/PGE has been applied satisfactorily for the estimation of cefixime present in different pharmaceuticals and biological samples by CV and DPV methods. The developed sensor has got lower over-potential (࢞Ep ) and enhanced diffusion current (id ). At CTAB/AuNPs/PGE the electron transfer kinetics of the cefixime is diffusion-controlled. The linearity was established in the range of 10 × 10−9 M to 30 × 10−8 M with a LOD of 1.21 × 10−10 M. Furthermore, the applicability of CTAB/AuNPs/PGE has been successfully illustrated for the determination of cefixime present in pharmaceutical formulations and biological fluids. Therefore, the proposed sensor is a promising analytical device for the electroanalysis of cefixime present in artificial and in real samples. Acknowledgement The authors are grateful to acknowledge the Department of Science and Technology (SERB), New Delhi, India for providing instrumental facilities to carry out the research work. Supplementary material Supplementary material associated with this article can be found, in the online version, at doi:10.1016/j.cdc.2019.100217. References [1] R. Jain, V.K. Gupta, N. Jadon, K. Radhapyari, Anal. Biochem. 407 (2010) 79–88. [2] N. Karimian, M.B. Gholivand, G. Malekzadeh, J. Electroanal. Chem. 771 (2016) 64–72. [3] F. Meng, X. Chen, Y. Zeng, D. Zhong, J. Chromatogr. B 819 (2005) 277–282.

12 [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] [39]

[40] [41] [42] [43] [44] [45] [46] [47] [48] [49] [50] [51] [52] [53] [54] [55] [56] [57] [58] [59] [60]

P. Manjunatha and Y.A. Nayaka / Chemical Data Collections 21 (2019) 100217 A. Golcu, B. Dogan, S.A. Ozkan, Talanta 67 (2005) 703–712. E. Nemutlu, S. Kır, D. Katlan, M.S. Beksa, Talanta 80 (2009) 117–126. M. Asadollahi-Babolia, A. Mani-Varnosfaderani, Measurement 47 (2014) 145–149. J. Wang, J.D. MacNeil, J.F. KayChemical, Analysis of Antibiotic Residues in Food, John Wiley & Sons, New Jersey, 2011. European Commission, Commission Regulation (EU) No. 37/2010, Off. J. Eur. Union L. 15 (2010) 1. A. Afkhami, F. Soltani-Felehgari, T. Madrakian, Electrochim. Acta 103 (2013) 125–133. A.F.M. El Walily, A.A.K. Gazy, S.F. Belal, E.F. Khamis, E.F. Khamis, Spectrosc. Lett. 33 (20 0 0) 931–937. L.I. Bebawy, K. El Kelani, L.A. Fattah, J. Pharm. Biomed. Anal. 32 (2003) 1219–1225. D.G. Shankar, K. Sushma, R.V. Lakshmi, Y.S. Rao, M.N. Reddy, T.K. Murthy, Asian J. Chem. 13 (2001) 1649–1654. A.M. El-Walily, A.A. Gazy, S.F. Belal, E.F. Khamis, J. Pharm. Biomed. Anal. 22 (20 0 0) 385–392. I.F. Al-Momani, J. Pharm. Biomed. Anal. 25 (2001) 751–757. L.O. White, D.S. Reeves, A.M. Lovering, A.P. MacGowan, J. Antimicrob. Chemother. 31 (1993) 450–451. S. Eric-Jovanovic, D. Agbada, D. Zivanov-Stakic, S. Viadimirov, J. Pharm. Biomed. Anal. 18 (1998) 893–898. T.M. Reddy, M. Sreedhar, S.J. Reddy, J. Pharm. Biomed. Anal. 31 (2003) 811–818. A. Golcu, B. Dogan, S.A. Ozkan, Talanta 67 (2005) 703–712. R. Jain, V.K. Gupta, N. Jadon, K. Radhapyari, Anal. Biochem. 407 (2010) 79–88. F. Meng, X. Chen, Y. Zeng, D. Zhong, J. Chromatogr. B 819 (2005) 277–282. M.M. Ghoneim, W. Baumann, E. Hammam, A. Tawfik, Talanta 64 (2004) 857–864. A.P.F. Turner, I. Karube, G.S. Wilson, Biosensors: Fundamentals and Applications, Oxford Science Publications, Oxford, 1987. S.A. Ozkan, B. Uslu, P. Zuman, Anal. Chim. Acta 457 (2002) 265–274. A.H. Al-Ghamdi, M.A. Al-Shadokhy, A.A. Al-Warthan, J. Pharm. Biomed. Anal. 35 (2004) 1001–1009. B. Uslu, S.A. Ozkan, Electrochim. Acta 49 (2004) 4321–4329. C.F. Ding, M.L. Zhang, F. Zhao, S.S. Zhang, Anal. Biochem. 378 (2008) 32–37. L. Agüí, C. Pe˜ na-Farfal, P. Yᘠnez-Sede˜ no, J.M. Pingarrón, Talanta 74 (2007) 412–420. L. Agüí, J. Manso, P. Yᘠnez-Sede˜ no, J.M. Pingarrón, Sens. Actuators B 113 (2006) 272–280. A. Afkhami, H. Ghaedi, T. Madrakian, M. Ahmadi, H. Mahmood-Kashani, Biosens. Bioelectron. 44 (2013) 34–40. A. Afkhami, H. Ghaedi, Anal. Methods 4 (2012) 1415–1420. A. Afkhami, T. Madrakian, H. Ghaedi, H. Khanmohammadi, Electrochim. Acta 66 (2012) 255–264. A. Afkhami, H. Bagheri, H. Khoshsafar, M. Saber-Tehrani, M. Tabatabaee, A. Shirzadmehr, Anal. Chim. Acta 746 (2012) 98–106. M.L. Yola, N. Atar, Z. Ustundag, A.O. Solak, J. Electroanal. Chem. 698 (2013) 9–16. M.L. Yola, N. Atarb, Electrochim. Acta 119 (2014) 24–31. M.L. Yola, T. Eren, N. Atar, Sens. Actuators B 210 (2015) 149–157. M.L. Yola, N. Atar, T. Eren, H. Karimi-Malehc, S. Wang, RSC Adv. 5 (2015) 65953–65962. V.K. Gupta, M.L. Yola, M.S. Qureshie, A.O. Solakf, N. Atare, Z. Üstündag, Sens. Actuators B 188 (2013) 1201–1211. P. Manjunatha, Arthoba Nayaka, Development of Gold Modified Disposable Pencil Graphite Electrode for the Electrochemical Investigation of Acetaminophen Present in Pharmaceutical formulations and Biological samples, Anal. Bioanal. Electrochem. 9 (2017) 841–861. P. Manjunatha, Y. Arthoba Nayaka, B.K. Chethana, C.C. Vidyasagar, R.O. Yathisha, Development of multi-walled carbon nanotubes modified pencil graphite electrode for the electrochemical investigation of aceclofenac present in pharmaceutical and biological samples, Sens. Bio-Sens. Res. 17 (2018) 7–17. J.H. Kim, G. Kang, Y. Nam, Y.K. Choi, Nanotech. 21 (2010) 0957–4484. H. Heli, A. Jabbari, S. Majdi, M. Mahjoub, A.A. Moosavi Movahedi, S. Sheibani, J. Solid State Electrochem. 13 (12) (2009) 1951–1958. M. Hajjizadeh, A. Jabbari, H. Heli, A.A. Moosavi-Movahedi, S. Haghgoo, Electrochim. Acta 53 (4) (2007) 1766–1774. H. Ibrahim, Y. Temerk, Sens. Actuators B 206 (2015) 744–752. F. Huang, Y. Peng, G. Jin, S. Zhang, J. Kong, Sensors 8 (2008) 1879–1889. Q. Liu, J. Huan, X. Dong, J. Qian, N. Hao, T. You, H. Mao, K. Wang, Sens. Actuators B. 235 (2016) 647–654. J.B. Raoof, R. Ojani, M. Baghayeri, Chin. J. Cats. 32 (11) (2011) 1685–1692. R. Jain, V.K. Gupta, N. Jadon, K. Radhapyari, Anal. Biochem. 407 (2010) 79–88. A. Afkhami, F. Soltani-Felehgari, T. Madrakian, Electrochim. Acta (2013) 125–133. D.E. Bayraktep, Z. Yazan, K. Polat, J. Electroanal. Chem. 780 (2016) 38–45. N. Spataru, B. V, E.Popa Sarada, D.A. Tryk, A. Fujishima, Anal. Chem. 73 (3) (2001) 514–519. M. Cubukcu, S. Timur, U. Anik, Talanta 74 (2007) 434–439. P.K. Kalambate, C.R. Rawool, A.K. Srivastava, Sensors and Actuators B. 237 (2016) 196–205. S.S. Nair, S. A.John, T. Sagara, Electrochim. Acta 54 (2009) 6837–6843. E. Laviron, J. Electroanaly. Chem. Inter. Electrochem. 101 (1979) 19–28. S. Shleev, J. Tkac, A. Christenson, I.T.R. Alexander, W.J. Yaropolov, L.G. Whittaker, Biosens. Bioelectron. 20 (2005) 2517–2554. W.X. Yunhua, J. Shengshui, Bioelectrochemistry 64 (2004) 91–97. P.K. Brahman, L. Suresh, V. Lokesh, S. Nizamuddin, Anal. Chim. Acta 917 (2016) 107–116. A.A. Ensafi, A.R. Allafchian, Colloids Surf. B 102 (2013) 687–693. Ali Fakhri, Sara Shahidi, Shilpi Agarwal, Vinod Kumar Gupta, Int. J. Electrochem. Sci. 11 (2016) 1530–1540. V. Rodenas, M.S. Garcia, C. Sanchez-Pedren, M.I. Albero, Talanta 52 (20 0 0) 517–523.