Potentiometric Determination of Ciprofloxacin in Physiological Fluids Using Carbon Paste and Nano‐Composite Carbon Paste Electrodes

Abstract

Nano‐composite carbon paste and simple carbon paste based potentiometric sensors were constructed and used for determination of ciprofloxacin at different pH values. Sensors were formulated utilizing graphite, suitable plasticizer, cirprofloxacinium‐phosphotungstate, as well as a highly lipophilic cation‐exchanger, sodium tetrakis(trifluoromethyl)phenyl borate. Effect of the incorporation of multi‐walled carbon nanotubes (MWCNTs) on the response characteristics of the prepared sensors was investigated. Results obtained were compared to that of a PVC‐sensor contains only the cation‐exchanger. In addition, the effect of solutions pH on the response characteristics was also studied; at pH 4.1, the slopes of bare carbon paste and MWCNTs‐based sensors were 55.7 and 66.6 mV/conc.decade in a concentration range of 10−2‐10−5 M with detection limits of 1.0x10−5 and 7.9x10−6 M, respectively. Although both sensors exhibited super‐Nernstian slopes at pH 2.0, the selectivity was improved compared to that measured at pH 4.1. Optimized sensors were successfully applied for the determination of ciprofloxacin in its pure form, pharmaceutical preparations, as well as spiked urine and serum samples, with high recovery.

Molecularly Imprinted Potentiometric Sensor for Nanomolar Determination of Pioglitazone Hydrochloride in Pharmaceutical Formulations

“…Five tablets of each type were well‐grounded and the amount equivalent to one tablet was dissolved in 0.1 M HCl to enhance solubility, warmed, and filtered to 25 mL with buffer. The PG concentration in these solutions was determined using direct potentiometry by using the calibration curve for determination of unknown concentration [41], and by the reference spectrophotometric method [42]. The recovery and statistical calculations were performed on three measurements.…”

“…PG in the different pharmaceutical preparations Diabetonorm ® (45 and 15 mg) was determined with sensor 4 applying direct potentiometry. The results were compared to those obtained by a reference spectrophotometric method [42], and it was very accurate and precise as ensured by recovery values and statistical calculations, Table 7. Comparing the characteristics of constructed sensor 4 to those of the previously reported in the literature (Table 8), significant improvements in a LDR, DL, and selectivity have been achieved by more than two orders of magnitudes in some cases.…”

Polyvinyl Chloride Modified Carbon Paste Electrodes for Sensitive Determination of Levofloxacin Drug in Serum, Urine, and Pharmaceutical Formulations

“…However, the sensor super-Nernstian response at pH 2.2 can be caused by the H + -interference [57,58]. Abdel-Haleem et al and Psomas reported that the best pH for potentiometric measurement of LF is 4.1 due to its existence in its monocationic form in the highest ratio with the coexistence of minimum amount of other LF species [31][32][33]; this also was reported for ciprofloxacin [57]. At pH = 4.1, LF + form dominates, and the sensors sub-Nernstian responses in Table 2 is due to the presence of other LF forms (LF 2+ and LF ± ), and due to the H-bond formation [57,58].…”

Copper Based Organic Framework Modified Electrosensor for Selective and Sensitive Detection of Ciprofloxacin

“…Over the years, a range of detection techniques like spectrophotometry [14], capillary electrophoresis [15], chromatography [16] and electrochemical techniques [17] are being used for the determination of ciprofloxacin in aqueous samples. But most of these methods require several time-consuming steps, complex instrumentation and trained personnel.…”