Successful antibiotic treatment of infections relies on accurate and rapid identification of the infectious agents. Pseudomonas aeruginosa is implicated in a wide range of human infections that mostly become complicated and life threating, especially in immunocompromised and critically ill patients. Conventional microbiological methods take more than three days to obtain accurate results. Pyocyanin is a distinctive electroactive biomarker for Pseudomonas aeruginosa. Here, we have prepared polyaniline/gold nanoparticles decorated ITO electrode and tested it to establish a rapid, diagnostic and highly sensitive pyocyanin sensor in a culture of Pseudomonas aeruginosa clinical isolates with high selectivity for traces of pyocyanin when measured in the existence of different interferences like vitamin C, uric acid, and glucose. The scanning electron microscopy and cyclic voltammetry techniques were used to characterize the morphology and electrical conductivity of the constructed electrode. The determined linear range for pyocyanin detection was from 238 μM to 1.9 μM with a detection limit of 500 nM. Compared to the screen-printed electrode used before, the constructed electrode showed a 4-fold enhanced performance. Furthermore, PANI/Au NPs/ITO modified electrodes have demonstrated the ability to detect pyocyanin directly in Pseudomonas aeruginosa culture without any potential interference with other species.

Successful antibiotic treatment of infections relies on accurate and rapid identification of the infectious agents. Pseudomonas aeruginosa is implicated in a wide range of human infections that mostly become complicated and life threating, especially in immunocompromised and critically ill patients. Conventional microbiological methods take more than three days to obtain accurate results. Pyocyanin is a distinctive electroactive biomarker for Pseudomonas aeruginosa. Here, we have prepared polyaniline/gold nanoparticles decorated ITO electrode and tested it to establish a rapid, diagnostic and highly sensitive pyocyanin sensor in a culture of Pseudomonas aeruginosa clinical isolates with high selectivity for traces of pyocyanin when measured in the existence of different interferences like vitamin C, uric acid, and glucose. The scanning electron microscopy and cyclic voltammetry techniques were used to characterize the morphology and electrical conductivity of the constructed electrode. The determined linear range for pyocyanin detection was from 238 μM to 1.9 μM with a detection limit of 500 nM. Compared to the screen-printed electrode used before, the constructed electrode showed a 4-fold enhanced performance. Furthermore, PANI/Au NPs/ITO modified electrodes have demonstrated the ability to detect pyocyanin directly in Pseudomonas aeruginosa culture without any potential interference with other species.

Successful antibiotic treatment of infections relies on accurate and rapid identification of the infectious agents. Pseudomonas aeruginosa is implicated in a wide range of human infections that mostly become complicated and life threating, especially in immunocompromised and critically ill patients. Conventional microbiological methods take more than three days to obtain accurate results. Pyocyanin is a distinctive electroactive biomarker for Pseudomonas aeruginosa. Here, we have prepared polyaniline/gold nanoparticles decorated ITO electrode and tested it to establish a rapid, diagnostic and highly sensitive pyocyanin sensor in a culture of Pseudomonas aeruginosa clinical isolates with high selectivity for traces of pyocyanin when measured in the existence of different interferences like vitamin C, uric acid, and glucose. The scanning electron microscopy and cyclic voltammetry techniques were used to characterize the morphology and electrical conductivity of the constructed electrode. The determined linear range for pyocyanin detection was from 238 μM to 1.9 μM with a detection limit of 500 nM. Compared to the screen-printed electrode used before, the constructed electrode showed a 4-fold enhanced performance. Furthermore, PANI/Au NPs/ITO modified electrodes have demonstrated the ability to detect pyocyanin directly in Pseudomonas aeruginosa culture without any potential interference with other species.

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Based on our previous work with “pseudostationary-ion exchanger sweeping”, we use this strategy to develop a sensitive, reliable and robust method for the analysis of the newly-FDA approved hepatitis C antiviral drugs namely; sofosbuvir (SOV), daclatasvir (DAC), ledipasvir (LED) and velpatasvir (VEP) in their pure forms and co-formulated pharmaceutical dosage forms using micellar electrokinetic chromatography (MEKC) as a separation method. For the first time, a successful separation of all the investigated compounds was achieved in less than 8 min using a basic background electrolyte (BGE) composed of 25 mmol L−1 SDS + 20% (v/v) ACN (acetonitrile) in 10 mmol L−1 disodium tetraborate buffer (final apparent pH is 9.90). A special focus was given to optimize the composition of the sample matrix to maintain the solubility of the analytes within the sample zone while gaining additional benefits regarding analyte zone focusing. It was found that replacing phosphoric acid (as a sample matrix) with a zwitterionic/isoelectric buffering compound (L-glutamic acid) has a substantial positive impact on the obtained enrichment efficiency. The interplay of other enrichment principles such as the retention factor gradient effect (RFGE) is also discussed. A full validation study is performed based on the pharmacopeial and ICH guidelines. The obtained limits of detection and quantitation are as low as 0.63 and 1.3 μg mL−1; respectively for SOV and DAC and 1.3 and 2.5 μg mL−1; respectively for LED and VEP using UV-DAD as a detection method. The selectivity of the developed method for determination of the studied compounds in their pharmaceutical dosage forms or in the presence of ribavirin (RIB) or elbasvir (ELB), which are other prescribed medications in the treatment regimen of patients with hepatitis C virus infection, is demonstrated. It is shown that with acidic sample matrix and basic BGE, an efficient and precise approach was designed in which analyte adsorption on the capillary wall was minimized while keeping repeatable peak height, peak area and migration time together with the highest possible enrichment efficiency.

Meropenem (MRP) and metronidazole (MTZ) are anti-microbial agents that concomitantly administrated for the management of severe acute pancreatic patients. An innovative direct, simple, rapid, cost effective and sensitive high performance thin layer chromatographic (HPTLC) method was successfully developed for in vitro and in vivo simultaneous determination of MRP and MTZ. The developed method relied on direct spotting of plasma without any pre-treatment due to low plasma protein binding of studied drugs followed by chromatographic separation and UV detection at isoabsorptive point of both drugs (306 nm). Chromatographic separation was done by methanol: acetonitrile: water (10:10:5, v/v/v) using formic acid as pH modifier. The Rf values were 0.55 ± 0.03 and 0.84 ± 0.02 for MRP and MTZ, respectively. Under optimum conditions, a linear relationship was obtained in concentration range of 100–1000 and 10–250 ng band−1 for MRP and MTZ, respectively with good correlation coefficient 0.9994–0.9997. The detection limits were 33.13 and 3.17 ng band−1 for MRP and MTZ, respectively. The method was validated according to ICH and US-FDA guidelines. The developed method was successfully applied for in vitro and in vivo quantification of MRP and MTZ in spiked human plasma and real plasma of acute pancreatic patients, respectively. Furthermore, the method was applied for assay of individual dosage forms of both drug.

Meropenem (MRP) and metronidazole (MTZ) are anti-microbial agents that concomitantly administrated for the management of severe acute pancreatic patients. An innovative direct, simple, rapid, cost effective and sensitive high performance thin layer chromatographic (HPTLC) method was successfully developed for in vitro and in vivo simultaneous determination of MRP and MTZ. The developed method relied on direct spotting of plasma without any pre-treatment due to low plasma protein binding of studied drugs followed by chromatographic separation and UV detection at isoabsorptive point of both drugs (306 nm). Chromatographic separation was done by methanol: acetonitrile: water (10:10:5, v/v/v) using formic acid as pH modifier. The Rf values were 0.55 ± 0.03 and 0.84 ± 0.02 for MRP and MTZ, respectively. Under optimum conditions, a linear relationship was obtained in concentration range of 100–1000 and 10–250 ng band−1 for MRP and MTZ, respectively with good correlation coefficient 0.9994–0.9997. The detection limits were 33.13 and 3.17 ng band−1 for MRP and MTZ, respectively. The method was validated according to ICH and US-FDA guidelines. The developed method was successfully applied for in vitro and in vivo quantification of MRP and MTZ in spiked human plasma and real plasma of acute pancreatic patients, respectively. Furthermore, the method was applied for assay of individual dosage forms of both drug.

Meropenem (MRP) and metronidazole (MTZ) are anti-microbial agents that concomitantly administrated for the management of severe acute pancreatic patients. An innovative direct, simple, rapid, cost effective and sensitive high performance thin layer chromatographic (HPTLC) method was successfully developed for in vitro and in vivo simultaneous determination of MRP and MTZ. The developed method relied on direct spotting of plasma without any pre-treatment due to low plasma protein binding of studied drugs followed by chromatographic separation and UV detection at isoabsorptive point of both drugs (306 nm). Chromatographic separation was done by methanol: acetonitrile: water (10:10:5, v/v/v) using formic acid as pH modifier. The Rf values were 0.55 ± 0.03 and 0.84 ± 0.02 for MRP and MTZ, respectively. Under optimum conditions, a linear relationship was obtained in concentration range of 100–1000 and 10–250 ng band−1 for MRP and MTZ, respectively with good correlation coefficient 0.9994–0.9997. The detection limits were 33.13 and 3.17 ng band−1 for MRP and MTZ, respectively. The method was validated according to ICH and US-FDA guidelines. The developed method was successfully applied for in vitro and in vivo quantification of MRP and MTZ in spiked human plasma and real plasma of acute pancreatic patients, respectively. Furthermore, the method was applied for assay of individual dosage forms of both drug.