A very simple high-performance liquid chromatographic method with fluorescence detection for the determination of gemifloxacin in human breast milk

Drugs in Human Milk Part 1: Practical and Analytical Considerations in Measuring Drugs and Metabolites in Human Milk

Human milk is a remarkable biofluid that provides essential nutrients and immune protection to newborns. Breastfeeding women consuming medications could pass the drug through their milk to neonates. Drugs can be transferred to human milk by passive diffusion or active transport. The physicochemical properties of the drug largely impact the extent of drug transfer into human milk. A comprehensive understanding of the physiology of human milk formation, composition of milk, mechanisms of drug transfer, and factors influencing drug transfer into human milk is critical for appropriate selection and use of medications in lactating women. Quantification of drugs in the milk is essential for assessing the safety of pharmacotherapy during lactation. This can be achieved by developing specific, sensitive, and reproducible analytical methods using techniques such as liquid chromatography coupled with mass spectrometry. The present review briefly discusses the physiology of human milk formation, composition of human milk, mechanisms of drug transfer into human milk, and factors influencing transfer of drugs from blood to milk. We further expand upon and critically evaluate the existing analytical approaches/assays used for the quantification of drugs in human milk.

Fabrication and Applications of Potentiometric Membrane Sensors Based on Specific Recognition Sites for the Measurement of the Quinolone Antibacterial Drug Gemifloxacin

Supramolecular gemifloxacin (GF) sensors have been developed. Supramolecular chemistry is primarily concerned with noncovalent intermolecular and intramolecular interactions, which are far weaker than covalent connections, but they can be exploited to develop sensors with remarkable affinity for a target analyte. In order to determine the dose form of the quinolone antibacterial drug gemifloxacin, the current study's goal is to adapt three polyvinylchloride (PVC) membrane sensors into an electrochemical technique. Three new potentiometric membrane sensors with cylindric form and responsive to gemifloxacin (GF) were developed. The sensors' setup is based on the usage of o-nitrophenyl octyl ether (o-NPOE) as a plasticizer in a PVC matrix, β-cyclodextrin (β-CD) (sensor 1), γ-cyclodextrin (γ-CD) (sensor 2), and 4-tert-butylcalix[8]arene (calixarene) (sensor 3) as an ionophore, potassium tetrakis (4-chlorophenyl) borate (KTpClPB) as an ion additive for determination of GF. The developed method was verified according to IUPAC guidelines. The sensors under examination have good selectivity for GF, according to their selectivity coefficients. The constructed sensors demonstrated a significant response towards to GF over a concentration range of 2.4 × 10^-6, 2.7 × 10^-6, and 2.42 × 10^-6 mol L^-1 for sensors 1, 2, and 3, respectively. The sensors showed near-Nernstian cationic response for GF at 55 mV, 56 mV, and 60 mV per decade for sensors 1, 2, and 3, respectively. Good recovery and relative standard deviations during the day and between days are displayed by the sensors. They demonstrated good stability, quick response times, long lives, rapid recovery, and precision while also exhibiting good selectivity for GF in various matrices. To determine GF in bulk and dose form, the developed sensors have been successfully deployed. The sensors were also employed as end-point indicators for titrating GF with sodium tetraphenyl borate.

Two Eco-Friendly Chromatographic Methods Evaluated by GAPI for Simultaneous Determination of the Fluoroquinolones Moxifloxacin, Levofloxacin, and Gemifloxacin in Their Pharmaceutical Products

In this paper, novel green HPLC and HPTLC chromatographic methods were developed for the concurrent determination of moxifloxacin, levofloxacin, and gemifloxacin in bulk and pharmaceutical products. The green HPLC method was used on Thermo C18 (4.6 × 250 mm, 5 µm). By mixing ethanol and 20 mM sodium dihydrogen phosphate dihydrate (pH 5) in a ratio of 25:75, v/v, the mobile phase was created using isocratic elution. The flow rate was 1 mLmin−1. The studied antibiotics were separated well within 9.5 min. The green HPTLC method was used on coated HPTLC aluminum sheets with Silica gel 60 F254 using a mobile phase mixture of water: acetone: ammonia (8:1:1, v/v/v). Compact and well-resolved peaks were obtained under chamber-saturation circumstances for the standard fluoroquinolone antibiotics. Both methods were optimized individually, validated by ICH, and assessed using the Green analytical procedure index (GAPI). The methods were applied to pharmaceutical products and compared with the published methods for the determination of each of these antibiotics individually, using Student’s t-test. They can be used by quality-control laboratories in pharmaceutical factories as sensitive eco-friendly methods for the analysis of these drugs and for the detection of cross-contamination during manufacturing processes.

Determination of Quinolone Antibiotic Residues in Human Serum and Urine Using High-Performance Liquid Chromatography/Tandem Mass Spectrometry

Quinolone antibiotic residues may pose potential threat to human health. A rapid and sensitive method was developed for the determination of quinolone residues in human serum and urine. After solid phase extraction (SPE) process, eight quinolone residues were analyzed by high-performance liquid chromatography/tandem mass spectrometry (HPLC-MS/MS) using ciprofloxacin-d8 as the internal standard. The relative standard deviation of intra-day and inter-day precision for the eight quinolones were less than 7.52% and the accuracies ranged from 95.8% to 103% in human serum, and from 94.1% to 104% in human urine. The extraction recoveries for the eight quinolones varied from 80.2% to 113% in human serum and 83.4% to 117% in human urine. The limit of detection for the eight quinolones was 0.50–1.00 ng/mL. Quinolone antibiotic residues in human serum and urine from 12 volunteers were successfully analyzed with the validated method. The SPE-HPLC-MS/MS method was useful for accurate determination of quinolone antibiotic residues in human body.

Bioanalytical challenge: A review of environmental and pharmaceuticals contaminants in human milk

An overview of bioanalytical methods for the determination of environmental and pharmaceutical contaminants in human milk is presented. The exposure of children to these contaminants through lactation has been widely investigated. The human milk contains diverse proteins, lipids, and carbohydrates and the concentration of these components is drastically altered during the lactation period providing a high degree of an analytical challenge. Sample collection and pretreatment are still considered the Achilles' heel. This review presents liquid chromatographic methods developed in the last 10 years for this complex matrix with focuses in the extraction and quantification steps. Green sample preparation protocols have been emphasized.