Selected pharmaceutical analysis in a wastewater treatment plant during COVID-19 infection waves in South Africa

Globally, an extensive range of pharmaceuticals are consumed daily to treat a variety of illnesses and diseases. Since the occurrence of the SARS-CoV-2 virus (COVID-19) outbreak, the use of pharmaceuticals has increased drastically in order to treat and prevent infection. Studies have shown that pharmaceutical usage is largely dependent on seasonal temperatures. This was explored in the present study and was verified by the results obtained. Versatile solid phase extraction (SPE) and liquid chromatography-mass spectrometry (LC-MS) methods were developed and validated for the accurate detection of target pharmaceuticals. Method percentage recoveries ranged from 73.53-100.70%, while the limit of detection (LOD) and limit of quantification (LOQ) ranged from 0.0330-0.886 mg L−1 and 0.0990-2.68 mg L−1, respectively. Resulting concentrations of pharmaceuticals used to treat chronic ailments such as diabetes, hypertension, tuberculosis and HIV/AIDS showed consistent daily usage while pharmaceuticals used for the treatment of COVID-19 and influenza showed distinct seasonal trends. Concentrations obtained for sulfamethoxazole hydroxylamine and sulfamethoxazole ranged from 0.05215-0.3438 mg L−1 and 0.009818-0.3002 mg L−1, respectively, while concentrations quantified for prednisolone and ivermectin ranged from 0.008775-0.4482 mg L−1 and 0.008520-0.979 mg L−1, respectively. Trends also directly correlated with the total number of active COVID-19 cases experienced in South Africa during sampling periods and this was confirmed using a one-way ANOVA test. P-values obtained for sulfamethoxazole hydroxylamine, sulfamethoxazole and ivermectin were below 0.05. © 2023 The Royal Society of Chemistry.

Fabric phase sorptive extraction combined with high performance liquid chromatography for the determination of favipiravir in human plasma and breast milk

A fast procedure obtained by the combination of fabric phase extraction (FPSE) with high performance liquid chromatography (HPLC) has been developed and validated for the quantification of favipiravir (FVP) in human plasma and breast milk. A sol-gel polycaprolactone-block-polydimethylsiloxane-block-polycaprolactone (sol-gel PCAP-PDMS-PCAP) coated on 100% cellose cotton fabric was selected as the most efficient membrane for FPSE in human plasma and breast milk samples. HPLC-UV analysis were performed using a RP C18 column under isocratic conditions. Under these optimezed settings, the overall chromatographic analysis time was limited to only 5 min without encountering any observable matrix interferences. Following the method validation procedure, the herein assay shows a linear calibration curve over the range of 0.2–50 µg/mL and 0.5–25 µg/mL for plasma and breast milk, respectively. The method sensitivities in terms of limit of detection (LOD) and limit of quantification (LOQ), validated in both the matrices, have been found to be 0.06 and 0.2 µg/mL for plasma and 0.15 and 0.5 µg/mL for milk, respectively. Intraday and interday precision and trueness, accordingly to the International Guidelines, were validated and were below 3.61% for both the matrices. The herein method was further tested on real samples in order to highlight the applicability and the advantage for therapeutic drug monitoring (TDM) applications. To the best of our knowledge, this is the first validated FPSE-HPLC-UV method in human plasma and breast milk for TDM purposes applied on real samples. The validated method provides fast, simple, cost reduced, and sensitive assay for the direct quantification of favipiravir in real biological matrices, also appliyng a well-known rugged and cheap instrument configuration. © 2022 Elsevier B.V.

Seasonal variation and ecological risk assessment of Pharmaceuticals and Personal Care Products (PPCPs) in a typical semi-enclosed bay — The Bohai Bay in northern China

The Bohai Bay as a typical semi-enclosed bay in northern China with poor water exchange capacity and significant coastal urbanization, is greatly influenced by land-based inputs and human activities. As a class of pseudo-persistent organic pollutants, the spatial and temporal distribution of Pharmaceuticals and Personal Care Products (PPCPs) is particularly important to the ecological environment, and it will be imperfect to assess the ecological risk of PPCPs for the lack of systematic investigation of their distribution in different season. 14 typical PPCPs were selected to analyze the spatial and temporal distribution in the Bohai Bay by combining online solid-phase extraction (SPE) and HPLC-MS/MS techniques in this study, and their ecological risks to aquatic organisms were assessed by risk quotients (RQs) and concentration addition (CA) model. It was found that PPCPs widely presented in the Bohai Bay with significant differences of spatial and seasonal distribution. The concentrations of ∑PPCPs were higher in autumn than in summer. The distribution of individual pollutants also showed significant seasonal differences. The high values were mainly distributed in estuaries and near-shore outfalls. Mariculture activities in the northern part of the Bohai Bay made a greater contribution to the input of PPCPs. Caffeine, florfenicol, enrofloxacin and norfloxacin were the main pollutants in the Bohai Bay, with detection frequencies exceeding 80 %. The ecological risk of PPCPs to algae was significantly higher than that to invertebrates and fish. CA model indicated that the potential mixture risk of total PPCPs was not negligible, with 34 % and 88 % of stations having mixture risk in summer and autumn, respectively. The temporary stagnation of productive life caused by Covid-19 weakened the input of PPCPs to the Bohai Bay, reducing the cumulative effects of the pollutants. This study was the first full-coverage investigation of PPCPs in the Bohai Bay for different seasons, providing an important basis for the ecological risk assessment and pollution prevention of PPCPs in the bay. © 2022 Elsevier B.V.

Occurrence and fate of antidepressants in the aquatic environment: Insights into toxicological effects on the aquatic life, analytical methods, and removal techniques

The consumption of antidepressants has increased on a global scale. These medications are frequently prescribed to treat mental health-related disorders and their usage is expected to rise in the future because the COVID-19 pandemic has intensified these problems significantly. These compounds have recently been detected in wastewater treatment plants and surface waters, raising concerns about their potential impacts on the envi-ronment. In this regard, the current review aims to critically evaluate the available information on the worldwide consumption of antidepressants, their occurrence, possible toxicological effects on aquatic organisms, and removal techniques. Several analytical methods for the extraction and quantification of antidepressant com-pounds have also been discussed. Additionally, risk quotients (RQs) have been estimated which indicates that sertraline posed the highest risk (RQ: 4.88) to the aquatic life followed by citalopram (RQ: 1.55) and bupropion (RQ: 1.12). It was observed that the aquatic organisms encountered behavioral, physical, cardiovascular, and reproductive changes after being exposed to antidepressant compounds. Some of these compounds have been satisfactorily removed (>85%) using a sequencing batch reactor with aerobic granulation of sludge. Physico-chemical processes such as photocatalysis, photochemical oxidation, and electrocatalysis exhibited more than 90% degradation efficiency in most cases. Moreover, integrating two or more physicochemical processes improved the treatment efficiency further. This study may help researchers to understand the threats posed by antidepressants to the environment and result in the development of innovative technologies for their removal.

Cuttlefish bone powder as an efficient solid-phase extraction sorbent of anti-SARS-CoV-2 drugs in environmental water.

Many antiviral drugs were developed to counteract coronavirus disease, 2019 (COVID-19) with severe acute respiratory syndrome. Therefore, the scientific community's efforts have focused on the detection and quantification of antiviral compounds currently being tested for COVID-19 treatment. Cuttlefish bone powder (CFBP) has been used for the first time as solid-phase extraction (SPE) sorbent for the extraction of SARS CoV-2 antiviral drugs (chloroquine, ritonavir and indomethacin) from water samples. An effective and sensitive method was developed by combining SPE and liquid chromatography- UV detection (LC-UV). An experimental design was applied for the optimization of extraction process. Experimental variables were optimized using Doehlert matrix. The developed method included 50 mg of CFBP sorbent, 20 mL of water sample at pH = 9 and 5 mL of ACN/KH2PO4 buffer solution (80:20, v/v) in the elution step. For validation of the method, selectivity, linearity precision, and sensitivity were evaluated. Extraction recovery percentage of all Sars cov-2 antivirals were above 98.2%. The detection and quantification limits were between 0.1 and 0.5 µg L-1 and 0.6 and 2 µg L-1, respectively. The current study suggested that CFBP has the application potential for the enhanced SPE of SARS CoV-2 antiviral drugs from water samples.

Functional metal-organic framework as high-performance adsorbent for selective enrichment of pharmaceutical contaminants in aqueous samples

Facile and sensitive analysis methods for pharmaceutical contaminants in aqueous environment are of vital importance for water safety, especially when large amounts of anti-viral drugs are being used, discharged and accumulated. In this work, we used functional metal-organic framework (MOF) as high-performance adsorbent for selective enrichment of such pharmaceutical contaminants in aqueous samples. The MOF was synthesized via a new synthesis method previously developed by our group and immobilized on paper membrane to be used in solid-phase extraction (SPE) device. Different metal ions were anchored by MOF to screen out the adsorbent with the best affinity. The targets were a potential anti-COVID-19 drug favipiravir, and its structural and functional analogues (ingredients or intermediates, other anti-viral drugs). To deeply understand the adsorption mechanisms, quantum calculation and computational fluid dynamics (CFD) simulation were both applied. The experimental and in-silico results together demonstrated that the as-prepared MOF adsorbent possessed high affinity and fast dynamics. The established SPE-based liquid chromatography (LC) method worked well in the range of 10-1000 ng/mL, with only 3 mg of adsorbent per device and 5 mL sample needed, and no mass spectrometer (MS) included, which was very efficient compared to commercial adsorbents. The results met the current detection needs in the application scenario, and inspirable for later design of well-behaved adsorbents.

Determination of Antiviral Drugs and Their Metabolites Using Micro-Solid Phase Extraction and UHPLC-MS/MS in Reversed-Phase and Hydrophilic Interaction Chromatography Modes.

Two new ultra-high performance liquid chromatography (UHPLC) methods for analyzing 21 selected antivirals and their metabolites were optimized, including sample preparation step, LC separation conditions, and tandem mass spectrometry detection. Micro-solid phase extraction in pipette tips was used to extract antivirals from the biological material of Hanks balanced salt medium of pH 7.4 and 6.5. These media were used in experiments to evaluate the membrane transport of antiviral drugs. Challenging diversity of physicochemical properties was overcome using combined sorbent composed of C18 and ion exchange moiety, which finally allowed to cover the whole range of tested antivirals. For separation, reversed-phase (RP) chromatography and hydrophilic interaction liquid chromatography (HILIC), were optimized using extensive screening of stationary and mobile phase combinations. Optimized RP-UHPLC separation was carried out using BEH Shield RP18 stationary phase and gradient elution with 25 mmol/L formic acid in acetonitrile and in water. HILIC separation was accomplished with a Cortecs HILIC column and gradient elution with 25 mmol/L ammonium formate pH 3 and acetonitrile. Tandem mass spectrometry (MS/MS) conditions were optimized in both chromatographic modes, but obtained results revealed only a little difference in parameters of capillary voltage and cone voltage. While RP-UHPLC-MS/MS exhibited superior separation selectivity, HILIC-UHPLC-MS/MS has shown substantially higher sensitivity of two orders of magnitude for many compounds. Method validation results indicated that HILIC mode was more suitable for multianalyte methods. Despite better separation selectivity achieved in RP-UHPLC-MS/MS, the matrix effects were noticed while using both chromatographic modes leading to signal enhancement in RP and signal suppression in HILIC.

Development of an easy and rapid analytical method for the extraction and preconcentration of chloroquine phosphate from human biofluids prior to GC-MS analysis.

A vortex assisted spraying based fine droplet formation liquid phase microextraction (VA-SFDF-LPME) method was developed to determine chloroquine phosphate at trace levels in human serum, urine and saliva samples by gas chromatography-mass spectrometry (GC-MS) with single quadrupole mass analyzer. In the first part, several liquid phase microextraction (LPME) and magnetic solid phase extraction (MSPE) methods were compared to each other in order to observe their extraction ability for the analyte. VA-SFDF-LPME method was selected as an efficient and easy extraction method due to its higher extraction efficiency. Optimization studies were carried out for the parameters such as extraction solvent type, sodium hydroxide volume/concentration, sample volume, spraying number and mixing type/period. Tukey's method based on post hoc test was applied to all experimental data for the selection of optimum values. Optimum extraction parameters were found to be 12 mL initial sample volume, two sprays of dichloromethane, 0.75 mL of 60 g/kg sodium hydroxide and 15 s vortex. Under the optimum conditions, limit of detection and quantification (LOD and LOQ) were calculated as 2.8 and 9.2 µg/kg, respectively. Detection power of the GC-MS system was increased by approximately 317 folds with the developed extraction/preconcentration method. The applicability and accuracy of the proposed method was evaluated by spiking experiments and percent recovery results for human urine, serum and saliva samples were found in the range of 90.9% and 114.0% with low standard deviation values (1.9-9.4).

Optimization of Analytical Procedure for In-hospital Rapid Quantification of Serum Level of Favipiravir in the Pharmacological Treatment of COVID-19.

An in-hospital rapid method for quantifying the serum level of favipiravir (FPV) in the pharmacological treatment of COVID-19 was developed by an appropriate combination of a solid-phase extraction treatment and a reversed-phase HPLC/UV detection system. The quantification method was well-validated and applied to measuring the serum FPV level in a clinical practice at a general hospital that accepts COVID-19 patients. Furthermore, an analysis of data from our preliminary interaction analysis revealed, for the first time, that FPV selectively forms complexes with ferric (Fe3+) and cupric (Cu2+) ions.

Accurate and sensitive determination of hydroxychloroquine sulfate used on COVID-19 patients in human urine, serum and saliva samples by GC-MS.

A rapid, accurate, and sensitive analytical method, ultrasonication-assisted spraying based fine droplet formation-liquid phase microextraction-gas chromatography-mass spectrometry (UA-SFDF-LPME-GC-MS), was proposed for the determination of trace amounts of hydroxychloroquine sulfate in human serum, urine, and saliva samples. To determine the best extraction strategy, several liquid and solid phase extraction methods were investigated for their efficiencies in isolation and preconcentration of hydroxychloroquine sulfate from biological matrices. The UA-SFDF-LPME method was determined to be the best extraction method as it was operationally simple and provided accurate results. Variables such as the extraction solvent, spraying number, sodium hydroxide concentration and volume, sample volume, mixing method, and mixing period were optimized for the proposed method using the one-variable-at-a-time approach. In addition, Tukey's method based on a post hoc comparison test was employed to evaluate the significant difference between the parameters inspected. After the optimization studies, the limit of detection (LOD) and limit of quantification (LOQ) were determined to be 0.7 and 2.4 µg/kg, respectively. The sensitivity of the GC-MS system based on the LOD was enhanced approximately 440-fold when the UA-SFDF-LPME method was employed. Spiking experiments were also conducted for the human serum, urine, and saliva samples to determine the applicability and accuracy of the proposed method. Recoveries for the human serum, urine, and saliva samples were found to be in the ranges of 93.9%-101.7%, 95.2%-105.0%, and 93.1%-102.3%, respectively. These results were satisfactory and indicated that the hydroxychloroquine sulfate level in the above biological samples could be analyzed using the proposed method.