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Optimized QuEChERS (quick, easy, cheap, effective, rugged and safe) method of sample preparation was employed for five selected pharmaceutical compounds on its advantage of simplicity, less extraction solvent and extraction time. Different parameters affecting the extraction efficiency of the target analyte was optimized. Since QuEChERS was developed for pesticides, uses of the method for pharmaceuticals need modification and evaluation of different parameters. Clean-up sorbents were evaluated for their matrix effect removal after extraction and a combination of d-SPE sorbent, MgSO4, PSA, C18 and diatomaceous earth found to be selective clean-up sorbent for the targeted compounds. The addition and amount of diatomaceous earth and EDTA during the clean-up and extraction steps, respectively, were also examined and the amount was optimized. Solvent type and composition, salt type and extraction time were also optimized and methanol, MgSO4 with NaCl salt and 5 min extraction time was obtained. The method was successfully applied to different vegetable samples collected from Addis Ababa, Ethiopia and Johannesburg, South Africa (carrot, cabbage and lettuce) and none of the target analytes were found in the sample investigated. The matrix effect study on vegetable samples collected was found very high that suppresses the signal during analysis. [ABSTRACT FROM AUTHOR]

The adsorption of Moringa oleifera seed cake, seed husk and water-soluble protein was studied for the removal of multi-class pharmaceuticals from water. The characteristic surface chemistry of the adsorbents was studied by Fourier-transform infrared spectroscopy analysis and scanning electron microscopy. Parameters affecting the extraction efficiency including pH, contact time and initial pharmaceutical concentration were optimized. The optimum conditions were found to be a sample pH of 5, a contact time of 80 min and a 0.5 mg/L initial concentration of the analyte. Equilibrium and kinetic models for pharmaceuticals adsorption were studied by considering the effects of concentration and contact time at the optimum conditions for each of the Moringa adsorbents. Freundlich's adsorption model was found to fit the experimental data. The kinetics of adsorption of all target analytes on the Moringa adsorbent was well defined by the pseudo-second-order model. The adsorption capacity for the seed cake ranged from 3-311, for the seed husk ranged from 7-413 and for water-soluble protein was 2-326 mg/g depending on individual pharmaceutical. The results obtained showed that the use of this plant-based sorbent can be considered as one of the most promising and low-cost for the removal of pharmaceuticals that needs surface modification to improve the adsorption for some pharmaceuticals. [ABSTRACT FROM AUTHOR]

In this work, molecularly imprinted polymer (MIP) was synthesized by a bulk polymerization method, characterized and parameters were optimized for adsorption of albendazole, ciprofloxacin, norfloxacin and venlafaxine in aqueous environment. The optimized MIP extraction parameters were adsorbent (MIP) mass 50 mg, sample pH of 9 and adsorption time of 20 min and 1 mL mixture of formic acid in water and methanol elution solvent. The adsorption experimental data fitted with the Freundlich isotherm model which indicates that the binding occurred on the heterogeneous sites and pseudo-second-order kinetic model best fitted which implied adsorption through chemisorption. The polymer selectivity was found to be in the order of albendazole > venlafaxine > norfloxacin > ciprofloxacin. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop and validate a high performance liquid chromatography (HPLC) method for the determination of thirteen selected pharmaceutical compounds (metformin, amoxicillin, chloroquine, theophylline, trimethoprim, caffeine, norfloxacin, ciprofloxacin, acetylsalicylic acid, doxycycline hyclate, metronidazole, albendazole and cloxacillin) in bulk and tablet dosage form. Chromatographic separation using a Kromasil C18 column, gradient elution with aqueous formic acid (0.1%), methanol and acetonitrile, a UV absorption wavelength of 250 nm and a mobile phase flow rate of 1 mL/min over a 22 min run time was optimized for complete separation of the selected target compounds. The method was validated and results for: linearity, precision, sensitivity, accuracy, specificity, suitability and method robustness were obtained and met the ICH guidelines. Calibration curve correlation coefficients ranged from 0.9985-0.9998 and the percentage relative standard deviations for repeated analysis was below 5%, indicating acceptable method precision. The limits of detection (LODs) and quantification (LOQs) ranged from 0.020-0.27 µg/L and 0.080-0.91 µg/L, respectively. The accuracy study yielded recoveries in the ranges 86.0-102% for pure compounds and 90.9-106% for compounds in tablet dosage form. The method is robust for small or deliberate changes to the chromatographic parameters and found to be appropriate for analysis of tablets for the determination of the thirteen pharmaceuticals. [ABSTRACT FROM AUTHOR]

In this study, selective removal of acidic pharmaceutical from aqueous media was investigated. The purpose of this work was to use the multi template molecularly imprinted polymer (MIP) for the selective extraction of naproxen, ibuprofen and diclofenac from aqueous samples. A multi template MIP was synthesized using a bulk polymerization method. The performance of the MIP in aqueous solutions was evaluated by optimizing several adsorption parameters. The optimized adsorption conditions were 50 mg of MIP, extraction time of 10 min and a sample pH of 4.6. The imprinting factors obtained for naproxen, ibuprofen and diclofenac were 1.25, 1.42, and 2.01, respectively, which corresponded to the selectivity order of diclofenac > ibuprofen > naproxen. Furthermore, the synthesized MIP showed great selectivity to the target compounds in the presence of gemfibrozil and fenoprofen. The data was modelled best by pseudo 2nd order which implied a chemisorption of pharmaceuticals onto MIP particles. Based on R 2 values, it was determined that the adsorption data fitted Langmuir isotherm which meant that the binding occurred on the homogeneous sites. The recovery in wastewater influent for naproxen, ibuprofen and diclofenac was 38%, 69% and 87%, respectively. [ABSTRACT FROM AUTHOR]

The influence of temperature on the extraction and selectivity of naproxen, ibuprofen, and triclosan by a thin-walled hollow fiber silicone rubber membrane was investigated. Determination of the diffusion coefficients and flux values at 25, 40, and 60 degrees Celsius was undertaken. The diffusion coefficient and flux were found to increase with temperature. It was also observed that at higher temperatures, mass transfer was influenced by the amount extracted in the acceptor phase. However, diffusion from the bulk donor phase through the hollow fiber silicone rubber membrane was shown to control the transport of analytes at lower temperatures. When applied to wastewater, the hollow fiber silicone rubber showed remarkable selectivity toward the analytes. However, at high temperatures, the amount of matrix components extracted also increased slightly. The amount extracted nearly doubled when extraction was performed at 40 degrees Celsius compared to 25 degrees Celsius, indicating that temperature increased the efficiency of the hollow fiber silicone rubber membrane. The application of the technique to municipal wastewater showed remarkable selectivity and reproducibility. The concentrations of these compounds were from 18.4 (1.37 percent) micrograms per liter for triclosan to 1.1 (0.16 percent) micrograms per liter for naproxen in the influent and 2.7 (0.29 percent) micrograms per liter for triclosan to 0.4 (0.01 percent) micrograms per liter for naproxen in the effluent. [ABSTRACT FROM AUTHOR]

In this article, a comprehensive review of applications of the hollow fibre-liquid phase microextraction (HF-LPME) for the isolation and pre-concentration of pharmaceuticals in water samples is presented. HF-LPME is simple, affordable, selective, and sensitive with high enrichment factors of up to 27,000-fold reported for pharmaceutical analysis. Both configurations (two- and three-phase extraction systems) of HF-LPME have been applied in the extraction of pharmaceuticals from water, with the three-phase system being more prominent. When compared to most common sample preparation techniques such as solid phase extraction, HF-LPME is a greener analytical chemistry process due to reduced solvent consumption, miniaturization, and the ability to automate. However, the automation comes at an added cost related to instrumental set-up, but a reduced cost is associated with lower reagent consumption as well as shortened overall workload and time. Currently, many researchers are investigating ionic liquids and deep eutectic solvents as environmentally friendly chemicals that could lead to full classification of HF-LPME as a green analytical procedure. [ABSTRACT FROM AUTHOR]

Sizeable amount of research has been conducted on the possible uptake of pharmaceuticals by plants from contaminated soil and water used for irrigation of crops. In most cases, pharmaceuticals are taken by roots and translocated into various tissues by transpiration and diffusion. Due to the plant uptake, the occurrence of pharmaceuticals in food sources such as vegetables is a public concern. Few review papers focusing on the uptake of pharmaceuticals, in particular antibiotics, and their translocation in plant tissues have been published. In the current review paper, the work conducted on the uptake of pharmaceuticals belonging to different therapeutic groups such as antibiotics, non-steroidal anti-inflammatory drugs, β-blockers and antiepileptics is reviewed. Such work includes the occurrence of pharmaceuticals in plants, translocation once taken by plants, toxicity studies as well as implications and future studies. Furthermore, the advantages and drawbacks associated with the detection and uptake of these pharmaceuticals by plants are discussed. In addition, the physico-chemical properties that could influence the plant uptake of pharmaceuticals are deliberated. [ABSTRACT FROM AUTHOR]

In this review paper, the milestones and challenges that have been achieved and experienced by African Environmental Scientists regarding the assessment of water pollution caused by the presence of pharmaceutical compounds in water bodies are highlighted. The identification and quantification of pharmaceuticals in the African water bodies is important to the general public at large due to the lack of information. The consumption of pharmaceuticals to promote human health is usually followed by excretion of these drugs via urine or fecal matter due to their slight transformation in the human metabolism. Therefore, large amounts of pharmaceuticals are being discharged continuously from wastewater treatment plants into African rivers due to inefficiency of employed sewage treatment processes. Large portions of African communities do not even have proper sanitation systems which results in direct contamination of water resources with human waste that contains pharmaceutical constituents among other pollutants. Therefore, this article provides the overview of the recent studies published, mostly from 2012 to 2016, that have focused on the occurrence of different classes of pharmaceuticals in African aqueous systems. Also, the current analytical methods that are being used in Africa for pharmaceutical quantification in environmental waters are highlighted. African Scientists have started to investigate the materials and remediation processes for the elimination of pharmaceuticals from water. [ABSTRACT FROM AUTHOR]

The contamination of paper products by various chemicals has been reported on a global level, but to date, no published research has investigated pharmaceutical contamination of paper-based products. In this study, pharmaceutical analysis was conducted on 42 samples collected from various points of the recycled paper value chain in Cape Town, South Africa, which included the various grades that may be included in the manufacturing of recycled paperboard. The analysis was achieved by ultrasonic-assisted extraction of paper samples before detection by UHPLC-Q Orbitrap. Quantification limits ranged from 1.15 pg/g for ketoprofen to 46.07 pg/g for methocarbamol. Pharmaceuticals identified in newspaper samples were dexamethasone, ketoprofen, and 17β-estradiol. The latter was also detected in paper shopping bags (up to 697.49 ng/g), infant bathtub packaging (280.62 ng/g), battery packaging (137.43 ng/g), and an egg carton (170.47 ng/g). Carbamazepine was also prominent with its concentration reaching 13.02 ng/g in a vegetable box. Suspect screening tentatively identified 14 additional pharmaceuticals in paper samples, with minocycline, prazepam, and anabolic steroids appearing more prominently. This pioneering study indicated that unintentional pharmaceutical exposure had expanded beyond environmental media to consumer products. [Display omitted] • The first reported occurrence of pharmaceuticals contamination in paper samples. • Targeted and suspect screening of various paper grades was performed. • Sensitive analytical method developed using UHPLC- Q Orbitrap. • Reveals the propagation of emerging contaminants beyond environmental matrices. • Consumer usage and waste management protocols contributed to pharmaceutical occurrence. [ABSTRACT FROM AUTHOR]

Pharmaceuticals are organic compounds used in medicines for alleviation of pain. Since 2017, there has been a steady increase on the availability of information on contamination of water resources caused by pharmaceuticals in some African countries. Thus far, most environmental monitoring studies of pharmaceuticals are conducted in South Africa while there is still no available data in majority of the African countries. Therefore, the knowledge on the presence of pharmaceuticals in African water resources is still lacking. In an attempt to provide more information in this aspect, this review article seeks to critically evaluate the progress made thus far by the African scientists in the environmental monitoring and assessment of pharmaceuticals. The most studied groups of pharmaceuticals in Africa are non-steroidal anti-inflammatory drugs, antibiotics, antiretroviral drugs and steroid hormones. Various remediation studies for selected pharmaceuticals in Africa are documented in literature. In the present review, the challenges facing the African researchers or countries on providing more scientific data on the occurrence of pharmaceuticals in water are discussed. Furthermore, the gaps and recommendations for future work are given. • Current status of pharmaceuticals in African water bodies is examined. • NSAIDs, ARVDs, antibiotics and steroid hormones are more prominent in African waters. • Coastal countries are more active in environmental monitoring of pharmaceuticals. • SPE coupled to LC systems is widely used in African countries. • Various adsorbents for removal of pharmaceuticals in contaminated water have been reported. [ABSTRACT FROM AUTHOR]

• A novel MASE-MIP based passive sampler was developed for five pharmaceuticals • An ionic liquid was utilized as a green receiver solution for the passive sampler • Matrix-matched sampling rates achieved ranged from 0.0007 - 0.0018 L d−1 • Only etilefrine (12.88 ng L−1) and methocarbamol (72.29 ng L−1) were quantified • Other drugs were not detected with detection limits from 2.45 - 3.26 ng L−1 In this work, we demonstrate the development, evaluation and pre-liminary application of a novel passive sampler for monitoring of selected pharmaceuticals in environmental waters. The samplers were calibrated in laboratory-based experiments to obtain sampling rates (Rs) for carbamazepine, methocarbamol, etilefrine, venlafaxine and nevirapine. Passive sampling was based on the diffusion of the target pharmaceuticals from surface water through a membrane bag which housed an ionic liquid as a green receiving solvent and a molecularly imprinted polymer. Effects of biofouling, deployment time and solvent type for the receiver phase were optimized for selective uptake of analytes in surface water. Notably, there was a decrease in the uptake of selected pharmaceuticals and consequently a decrease in their sampling rates in the presence of biofouling. The optimum matrix-matched sampling rates ranged from 0.0007 - 0.0018 L d−1 whilst the method detection and quantification limits ranged from 2.45 - 3.26 ng L−1 and 8.06 - 10.81 ng L−1, respectively. The optimized passive sampler was deployed in a dam situated in the heart of a typical highly populated township in the Gauteng Province of South Africa. Only etilefrine and methocarbamol were detected and quantified at maximum time weighted average concentrations of 12.88 and 72.29 ng L−1, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

This work demonstrates development and evaluation of a two-way technique based on the combination of membrane assisted solvent extraction and a molecularly imprinted polymer (MASE-MIP) for selective and efficient extraction of five selected pharmaceuticals belonging to five different therapeutic classes. The pharmaceuticals were extracted from surface water samples followed by liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-qTOF/MS) determination. A central composite design was applied to optimize the influence of the sample salt content, the stirring rate, the stirring time and the amount of MIP on the extraction of an anticonvulsant (carbamazepine), a cardiac stimulant (etilefrine), a muscle relaxant (methocarbamol), an antiretroviral (nevirapine) and an antidepressant (venlafaxine) from surface water. Optimization of the analytical method was performed by spiking water with a mixture of all five pharmaceuticals at 500 ng mL−1. Optimum extraction conditions for a sample volume of 18 mL were found to be 5 g of salt content, a stirring rate of 400 rpm, an extraction time of 60 min and 50 mg of MIP. The MASE-MIP-LC-qTOF/MS method gave detection and quantification limits ranging from 0.09 to 0.20 ng mL−1 and 0.31–0.69 ng mL−1, respectively. The spiked river water samples yielded recoveries ranging from 38 to 91% for the selected model compounds belonging to the five classes of pharmaceuticals. Upon the application of the developed analytical method in water analysis, all selected pharmaceuticals were detected in South African river water with nevirapine and venlafaxine being more prominent attaining the maximum concentrations of 1.64 and 2.48 ng mL−1, respectively. [Display omitted] • A MASE-MIP technique was developed for monitoring pharmaceuticals in water samples. • Optimization of the analytical method was done using a central composite design. • Good experimental and statistical method performances were observed. • Method was applied in extraction of 5 pharmaceutical classes in river water. • Nevirapine (1.64 ng mL−1) and venlafaxine (2.48 ng mL−1) were more prominent. [ABSTRACT FROM AUTHOR]