Optimization and validation of high-performance liquid chromatography using modified QuEChERS to determine anthelmintic drugs in mutton.

The aim of this study was to rapidly determine the presence of anthelmintic drugs in sheep meat using the optimized high-performance liquid chromatography-ultraviolet (HPLC-UV) method with modified QuEChERS (quick, easy, cheap, effective, rugged, safe) technology. Fifty fresh sheep meat samples from different slaughterhouses were collected. A double extraction procedure (QuEChERS/HPLC-UV technology) was used to extract the target analytes. A multilevel calibration curve from 1 to 1000 g/kg was used to establish instrument linearity for rafoxanide, albendazole, and closantel, whereas 0.1-100 µg/kg was used for ivermectin, levamisole, and oxyclozanide to find the lowest concentration, maximum residue limit (MRL), and occupied range for targeted analytes. The concentration levels were used to investigate the linearity, whereas several certified reference materials were applied to determine accuracy. The process was linear for all combinations, from the limit of quantification (LOQ) to the maximum concentration. The LOQ was established at 0.5 µg/kg for ivermectin, levamisole, and oxyclozanide and 10 µg/kg for rafoxanide, albendazole, and closantel. Recovery values were 70%-120%, and repeatability/reproducibility stated in relative standard deviation was obtained at less than 20%. QuEChERS method revealed that most meat samples contained anthelmintic drug residues, of which the majority exceeded the MRLs. Thus, the drugs should be used correctly in animals to avoid residues in food for human consumption.

Quantitative Analysis of Abamectin, Albendazole, Levamisole HCl and Closantel in Q-DRENCH Oral Suspension Using a Stability-Indicating HPLC-DAD Method.

Combination therapy of many anthelmintic drugs has been used to achieve fast animal curing. Q-DRENCH is an oral suspension, containing four different active drugs against GIT worms in sheep, commonly used in Australia and New Zeeland. The anti-parasitic drugs are Albendazole (ALB), Levamisole HCl (LEV), Abamectin (ABA), and Closantel (CLO). The main purpose of this study is to present a new simultaneous stability-indicting HPLC-DAD method for the analysis of the four drugs. The recommended liquid system was 1 mL of Triethylamine/L water, adjusting the pH to 3.5 by glacial acetic acid: acetonitrile solvent (20:80, v/v). Isocratic elusion achieved the desired results of separation at a 2 mL/min flow rate using Zorbax C-18 as a stationary phase. Detection was performed at 210 nm. The linearity ranges were 15.15 to 93.75 µg/mL for ALB, 25 to 150 µg/mL for LEV, 30 to 150 µg/mL for ABA, and 11.7 to 140.63 µg/mL for CLO. Moreover, the final greenness score was 0.62 using the AGREE tool, which reflects the eco-friendly nature. Moreover, the four drugs were determined successfully in the presence of their stressful degradation products. This work presents the first chromatographic method for simultaneous analysis for Q-DRENCH oral suspension drugs in the presence of their stressful degradation products.

Simple method for the determination of anthelmintic drugs in milk intended for human consumption using liquid chromatography-tandem mass spectrometry.

BACKGROUND: Helminth infections in animals to be consumed by humans are an important medical and public health problem. Pharmaceutical research has focused on developing new anthelmintic drugs for parasite control in these animals. However, the incorrect use of anthelmintics can leave residues in animal products intended for human consumption. Their determination is therefore crucial in terms of food safety. RESULTS: In this work, a simple and sensitive method has been developed for the analysis of anthelmintic drugs in milk. The method involves extraction of the analytes using a QuEChERS (quick, easy, cheap, effective, rugged, and safe) method, and separation and determination by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The use of a core-shell column significantly reduced the analysis time compared with conventional columns. The method was validated and applied to the analysis of different commercial milk samples: whole, semi-skimmed and skimmed cows' milk, and goats' milk. None of the benzimidazoles studied was found in the samples analyzed, so these were spiked with the analytes at three concentration levels (10, 50, and 100 µg kg-1 ). CONCLUSIONS: The proposed method provided high sensitivity compared with other methods for the determination of anthelmintics in milk samples, at concentration levels well below the established maximum residue limit (MRLs) values. The proposed method is simple, easy, precise, accurate, and leads to good recovery levels. It can be used successfully for the routine analysis. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Practical High-Throughput Method to Screen Compounds for Anthelmintic Activity against Caenorhabditis elegans.

In the present study, we established a practical and cost-effective high throughput screening assay, which relies on the measurement of the motility of Caenorhabditis elegans by infrared light-interference. Using this assay, we screened 14,400 small molecules from the "HitFinder" library (Maybridge), achieving a hit rate of 0.3%. We identified small molecules that reproducibly inhibited the motility of C. elegans (young adults) and assessed dose relationships for a subset of compounds. Future work will critically evaluate the potential of some of these hits as candidates for subsequent optimisation or repurposing as nematocides or nematostats. This high throughput screening assay has the advantage over many previous assays in that it is cost- and time-effective to carry out and achieves a markedly higher throughput (~10,000 compounds per week); therefore, it is suited to the screening of libraries of tens to hundreds of thousands of compounds for subsequent evaluation and development. The present phenotypic whole-worm assay should be readily adaptable to a range of socioeconomically important parasitic nematodes of humans and animals, depending on their dimensions and motility characteristics in vitro, for the discovery of new anthelmintic candidates. This focus is particularly important, given the widespread problems associated with drug resistance in many parasitic worms of livestock animals globally.

Occurrence and risk assessment of anthelmintics in Tuojiang River in Sichuan, China.

Recently, emerging pollutants, such as anthelmintics have attracted an increasing attention worldwide due to their extensive use and notable stability. However, the information on anthelmintics in the environment of southwest China is scarce. Thus, the occurrence, ecological risk and exposure evaluation of nineteen anthelmintics in Tuojiang River, which is one of the largest tributaries of Yangtze River, and drinking water source of Sichuan, southwest China, were investigated. The result showed that the detection frequency of anthelmintics was relatively high in Tuojiang River, ranging from 65% to 100% in river water. Among the seven kinds of anthelmintics, benzimidazoles are the primary anthelmintics, with concentrations up to 61.12 ng/L and 596.06 ng/g in water and sediment of the Tuojiang river, respectively. The total concentration of 19 anthelmintics in sediment samples from non-agricultural area was higher than that in agricultural area(p = 0.000 < 0.05). This could be attributed to anthropogenic activities, which lead to greater discharge and accumulation of anthelmintics in residential area along the river. It's worth to mention that the highest total concentrations of anthelmintics (109.28 ng/L) was found at the junction of rivers in R31 site. The results could be ascribed to the complexity of junction of Tuojiang River and Yangtze River, which could influence the distribution of pollutant. Besides, the ecological risk assessment showed that the macrocyclic lactones rather than benzimidazoles had relatively high toxicity to non-target organisms in aquatic environment (p = 0.000 < 0.05), with the highest RQEcotox value of 101 for Daphnia magna, while benzimidazoles had relatively high concentrations. The exposure risk could be ignored for both children and adults because the daily intake of anthelmintics via water ingestion were below 10 ng/kg/d. In addition, strong correlations were found between sucralose and most of the selected anthelmintics in Tuojiang River, indicating that sucralose might be a good tracer to evaluated the source of anthelmintics in surface water. This study provides the levels, risks and even some tracer information of pollutants for better understanding of anthelmintics in southwest China.

Anthelmintic resistance in Creole horses in the South of Rio Grande do Sul, Brazil / [Resistência anti-helmíntica em equinos da raça Crioula no sul do Rio Grande do Sul, Brasil]

The objective of the study was to evaluate the antiparasitic resistance against horse nematodes in the South of Rio Grande do Sul, Brazil. The results concerning the tests of anthelmintic efficacy on horses, stored in the database of the Parasitic Diseases Study Group (GEEP) - Veterinary Faculty, at the Federal University of Pelotas (UFPel), were carried out in the laboratory from 2018 to 2019. Stool samples were received from farms with breeding of adult female and male Criollo horses naturally infected, located in municipalities in the country's southern region. The antiparasitic agents tested were Triclorfon + Fenbendazole, Closantel + Albendazole, Ivermectin + Praziquantel, Fenbendazole, Ivermectin, Doramectin, Mebendazole and Moxidectin. Techniques such as Gordon and Whitlock, Coproculture and Fecal Egg Count Reduction Test were performed. Of all the antiparasitic drugs tested, it was observed that only treatments with Ivermectin 2% showed desired values. The observed results indicate that resistance to macrocyclic lactones is usual in equine parasites in this Brazilian region, despite the results with isolated Ivermectin.(AU)

O objetivo deste estudo é avaliar a resistência antiparasitária contra nematodeos de equinos no sul do Rio Grande do Sul, Brasil. Os resultados referentes aos testes de eficácia anti-helmíntica em cavalos, armazenados no banco de dados do Grupo de Estudos de Doenças Parasitárias (GEEP) - Faculdade de Veterinária, da Universidade Federal de Pelotas (UFPel), foram realizados em laboratório, no período de 2018 a 2019. Amostras de fezes foram recebidas de fazendas com criação de cavalos Crioulos adultos fêmeas e machos naturalmente infectados, localizadas em municípios da região Sul do país. Os agentes antiparasitários testados foram triclorfon + fenbendazol, closantel + ivermectina + praziquantel, fenbendazol, ivermectina, doramectina, mebendazol e moxidectina. Técnicas como Gordon e Whitlock, coprocultura e teste de redução da contagem de ovos fecais foram realizadas. De todos os antiparasitários testados, observou-se que apenas os tratamentos com ivermectina 2% apresentaram os valores desejados. Os resultados indicam que a resistência às lactonas macrocíclicas é comum em parasitas equinos nessa região brasileira, apesar dos resultados com ivermectina isolada.(AU)

In vitro effects of tropisetron and granisetron against Echinococcus granulosus (s.s.) protoscoleces by involvement of calcineurin and calmodulin.

BACKGROUND: Cystic echinococcosis (CE) is a disease caused by the larval stage of Echinococcus granulosus sensu lato  (s.l.). The treatment of CE mainly relies on the use of benzimidazoles, which can commonly cause adverse side effects. Therefore, more efficient treatment options are needed. Drug repurposing is a useful approach for advancing drug development. We have evaluated the in vitro protoscolicidal effects of tropisetron and granisetron in E. granulosus sensu stricto (s.s.) and assessed the expression of the calcineurin (CaN) and calmodulin (CaM) genes, both of which have been linked to cellular signaling activities and thus are potentially promising targets for the development of drugs. METHODS: Protoscoleces (PSC) of E. granulosus (s.s.) (genotype G1) obtained from sheep hepatic hydatid cysts were exposed to tropisetron and granisetron at concentrations of 50, 150 and 250 µM for various periods of time up to 10 days. Cyclosporine A (CsA) and albendazole sulfoxide were used for comparison. Changes in the morphology of PSC were investigated by light microscopy and scanning electron microscopy. Gene expression was assessed using real-time PCR at the mRNA level for E. granulosus calcineurin subunit A (Eg-CaN-A), calcineurin subunit B (Eg-CaN-B) and calmodulin (Eg-CaM) after a 24-h exposure at 50 and 250 µM, respectively. RESULTS: At 150 and 250 µM, tropisetron had the highest protoscolicidal effect, whereas CsA was most effective at 50 µM. Granisetron, however, was less effective than tropisetron at all three concentrations. Examination of morphological alterations revealed that the rate at which PSC were killed increased with increasing rate of PSC evagination, as observed in PSC exposed to tropisetron. Gene expression analysis revealed that tropisetron at 50 µM significantly upregulated Eg-CaN-B and Eg-CaM expression while at 250 µM it significantly downregulated both Eg-CaN-B and Eg-CaM expressions; in comparison, granisetron decreased the expression of all three genes at both concentrations. CONCLUSIONS: Tropisetron exhibited a higher efficacy than granisetron against E. granulosus (s.s.) PSC, which is probably due to the different mechanisms of action of the two drugs. The concentration-dependent effect of tropisetron on calcineurin gene expression might reflect its dual functions, which should stimulate future research into its mechanism of action and evaluation of its potential therapeutical effect in the treatment of CE.

Determination of Anthelmintic and Antiprotozoal Drug Residues in Fish Using Liquid Chromatography-Tandem Mass Spectrometry.

The objective of this study is to develop a comprehensive and simple method for the simultaneous determination of anthelmintic and antiprotozoal drug residues in fish. For sample preparation, we used the "quick, easy, cheap, effective, rugged, and safe" (QuEChERS) method with a simple modification. The sample was extracted with water and 1% formic acid in acetonitrile/methanol (MeCN/MeOH) (95:5, v/v), followed by phase separation (salting out) with MgSO4 and NaCl (4:1, w/w). After centrifugation, an aliquot of the extract was purified by dispersive solid-phase extraction (d-SPE) prior to liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The method was validated at three concentration levels for all matrices, in accordance with the Codex guidelines (CAC/GL-71). Quantitative analysis was performed using the method of matrix-matched calibration. The recoveries were between 60.6% and 119.9%, with coefficients of variation (CV) <30% for all matrices. The limit of quantitation (LOQ) of the method ranged from 0.02 µg kg-1 to 4.8 µg kg-1 for all matrices. This comprehensive method can be used for the investigation of both anthelmintic and antiprotozoal drugs belonging to different chemical families in fishery products.

Essential oil of Mentha pulegium induces anthelmintic effects and reduces parasite-associated oxidative stress in rodent model.

Following the previous findings reported by the present authors on the anthelmintic effect of hydro-ethanolic extract of Mentha pulegium, the volatile constituents of M. pulegium are now assessed in the present study by exploring its anthelmintic and its antioxidant proprieties using in vitro and in vivo assays. Egg hatch assay (EHA) and adult worm's motility assays (AWMA) were used to assess the in vitro activity against Haemonchus. contortus. The in vivo anthelmintic potential was evaluated in mice infected with Heligmosomoides polygyrus using faecal egg count reduction (FECR) and total worm count reduction (TWCR). M. pulegium EO demonstrated 100% inhibition in the EHA at 200 µg/mL (IC50 = 56.36 µg/mL). In the AWM assay, EO achieved total worms paralysis 6 h after treatment exposure. This nematicidal effect was associated to morphological damages observed in the cuticular's worm using environmental scanning electron microscopy (ESEM). At 400 mg/kg, M. pulegium oil showed 75.66% of FECR and 80.23% of TWCR. The antioxidant potential of this plant was also monitored by several in vitro assays: total antioxidant capacity was 205.22 mg GAE/g DW, DPPH quenching effect was IC50 = 140 µg/mL, ABTS activity IC50 = 155 µg/mL and FRAP effect of 660 µg/mL. Regarding the in vivo assay, M. pulegium EO demonstrated a protective effect against oxidative stress by increasing the activity of the endogenous antioxidants (SOD, CAT and GPx) during H. polygyrus infection.

Use of eosin for green spectroscopic determination of mebendazole.

New, sensitive, and reliable spectroscopic methods were constructed for the fast determination of the anthelmintic drug mebendazole. The methods depended on the reaction of the amino group in mebendazole with eosin in acidic medium forming an ion pair complex. The first method, Method I, relied on quenching of the native fluorescence of eosin after reaction with mebendazole at pH 3.7 using acetate buffer. Fluorescence quenching was measured at 538 nm after excitation at 518 nm. This method showed a linear response over the concentration range 5.0-20.0 µg/ml. The second method, Method II, was based on measuring the absorbance of the formed complex at 554 nm; the method showed good linearity from 7.0 to 22.0 µg/ml. Different parameters that influenced the formation of the reaction product were carefully investigated to reach the optimized conditions. A comparison between the proposed methods and a previous spectrophotometric method was carried out and there was no significant difference between them. The methods could be applied successfully to determine mebendazole in its tablet form. Moreover, the methods used water as diluting solvent, which made them compatible with the 'green' analytical chemistry principles. No organic solvents were used throughout the study.

Rapid and Sensitive Drug Quantification in Tissue Sections Using Matrix Assisted Laser Desorption Ionization-Ion Mobility-Mass Spectrometry Profiling.

Ion mobility spectrometry (IMS) represents a considerable asset for analytics of complex samples as it allows for rapid mass spectrometric separation of compounds. IMS is even more useful for the separation of isobaric compounds when classical separation methods such as liquid chromatography or electrophoresis cannot be used, e.g., during matrix-assisted laser desorption/ionization (MALDI) analyses of biological surfaces. In the present study, we proved the usefulness of IMS for pharmacological applications of MALDI analyses on tissue sections. To illustrate our proof-of-concept, we used the anthelmintic drug mebendazole (MBZ) as a model. Using this exemplary drug, we demonstrated the possibility of using ion mobility to discriminate a drug in tissues from the biological background that masked its signal at low concentrations. In this proof-of-concept, the IMS mode together with the use of a profiling approach for sample preparation enabled quantification of the model drug MBZ from tissue sections in the concentration range 5 to 5,000 ng/g and with a limit of detection of 1 ng/g of tissue, within 2 h. This study highlights the importance of IMS as a separation method for on-surface quantification of drugs in tissue sections.

Microdroplet-captured tapes for rapid sampling and SERS detection of food contaminants.

Simple, effective, and rapid detection of chemically relevant hazards is a highly desirable research goal, which can provide early-warning information to improve the patient-care outcomes for public health. Here, we introduce a microdroplet-captured tape toward rapid SERS screening of food contaminants. The dominant sensing unit lies on functionalized microwell in conductive carbon tapes, which is simply prepared by physical punching, magnetron sputtering and electrochemical deposition of Au nanodendrites. The tape-based sensors not only possess highly branched Au nanodendrites in microwell for promoting SERS activity, but also enable anchoring the microdroplets via direct dip-pulling from pristine analytes solutions upon sticky incorporated on a glove. Early-warning SERS detection of food contaminants including Sudan-1, thiram, and thiabendazole from the real samples can be achieved by such simple sampling method. These tape-based sensors with a facile operation module and accessible signal read-out represent an innovative point-of-care testing (POCT) device for forensic, military, consumer protection, environmental monitoring, and food safety applications.

Effect of nutraceuticals on acanthocephalan Neoechinorhynchus buttnerae and its toxicity to the host tambaqui Colossoma macropomum.

The production of tambaqui Colossoma macropomum has been undergoing financial losses due to parasitic infection by the acanthocephalan Neoechinorhynchus buttnerae, raising an alert for aquaculture in South America. The lack of adequate treatment and use of unlicensed chemicals encourages research for alternative solutions with minimal side effects. The objectives of this study were to evaluate the in vitro antiparasitic potential of commercial nutraceutical products (Natumix® and BioFish®) against N. buttnerae and to assess the respective in vivo toxic effects on the host tambaqui. For in vitro assays, parasitized fish were necropsied for acanthocephalans sampling. The parasites were exposed to three concentrations (0.078, 0.313 and 1.25 mg/ml) of each product, as well as controls (one without product and another with a solubilizer). For the in vivo acute toxicity test, juvenile fish (<0.1 g) were exposed to five increasing concentrations of each product. Mortality of tambaqui was recorded at 24, 48, 72 and 96 h. The estimated lethal concentration (LC) for 10, 50, 90 and 99% of fish was determined to classify the toxicity of the products on the target species. After in vitro efficacy tests, the highest concentrations (1.25 mg/ml) caused 100% mortality of the parasites in both products, but only Natumix® caused 100% mortality using the intermediate concentration (0.313 mg/ml) after 24 h. According to the acute toxicity result, the LC50 classified the nutraceutical products as slightly toxic for tambaqui. The tested products had a parasiticidal effect on N. buttnerae, and the toxicity test showed that both products have therapeutic potential when added to the diet.

Drug Screening for Discovery of Broad-spectrum Agents for Soil-transmitted Nematodes.

Soil-transmitted nematodes (STNs), namely hookworms, whipworms, and ascarids, are extremely common parasites, infecting 1-2 billion of the poorest people worldwide. Two benzimidazoles, albendazole and mebendazole, are currently used in STN mass drug administration, with many instances of low/reduced activity reported. New drugs against STNs are urgently needed. We tested various models for STN drug screening with the aim of identifying the most effective tactics for the discovery of potent, safe and broad-spectrum agents. We screened a 1280-compound library of approved drugs to completion against late larval/adult stages and egg/larval stages of both the human hookworm parasite Ancylostoma ceylanicum and the free-living nematode Caenorhabditis elegans, which is often used as a surrogate for STNs in screens. The quality of positives was further evaluated based on cheminformatics/data mining analyses and activity against evolutionarily distant Trichuris muris whipworm adults. From these data, two pairs of positives, sulconazole/econazole and pararosaniline/cetylpyridinium, predicted to target nematode CYP-450 and HSP-90 respectively, were prioritized for in vivo evaluation against A. ceylanicum infections in hamsters. One of these positives, pararosaniline, showed a significant impact on hookworm fecundity in vivo. Taken together, our results suggest that anthelmintic screening with A. ceylanicum larval stages is superior to C. elegans based on both reduced false negative rate and superior overall quality of actives. Our results also highlight two potentially important targets for the discovery of broad-spectrum human STN drugs.

Araticum (Annona crassiflora Mart.) as a source of nutrients and bioactive compounds for food and non-food purposes: A comprehensive review.

Araticum (Annona crassiflora Mart.) is a fruitful tree native to the Brazilian Cerrado biome that holds high nutritional, functional and economic potential. This plant has been used since ancient times by folk medicine for the treatment of several pathological conditions. There has been increasing interest in the development of pulp-based food products as well as the by-products utilization to obtain value-added ingredients. Understanding the chemical composition and biological activities of different botanical parts of Annona crassiflora Mart. provides a basis to support future researches and applications. In this context, this paper carries out an exhaustive review of the scientific literature, on the main phytochemicals of different botanical parts of Annona crassiflora Mart. (fruit, leaves, stem and root) and their biological activities, assessing their potential uses for several industrial segments. Annona crassiflora Mart. fruits and especially their by-products (peel and seeds) and leaves have been shown a wide range of bioactive compounds such as phenolic compounds, alkaloids, annonaceous acetogenins, tocols, carotenoids, phytosterols, dietary fiber, vitamins, minerals and essential oils. These compounds contribute to various biological activities, including antioxidant, hepatoprotective, anti-inflammatory, antitumoral, analgesic, antidiabetic, skin healing, antidiarrhoeic, antimicrobial, antiparasitic, insecticide and herbicide activities of Annona crassiflora Mart. extracts. Therefore, these findings demonstrate that Annona crassiflora Mart. fruit, by-products and leaves can be excellent candidates to be used as functional foods and/or sources for obtaining bioactive compounds for the food, cosmetics and pharmaceutical applications.

The Anthelmintic Effects of Medicinal Plant Extracts Against Paramphistome Parasites, Carmyerius spatiosus.

INTRODUCTION: Paramphistomosis is a disease caused by the rumen flukes which cause an acute gastroenteritis and anemia with high mortality particularly in young ruminants. MATERIALS AND METHODS: In this study, we have investigated the anthelmintic effect of medicinal plant extracts from leaves and heartwoods of Cassia siamea L., roots of Plumbago zeylanica L. and Plumbago indica L., and leaves of Terminalia catappa L. against Carmyerius spatiosus. RESULTS: The highest anthelminthic effect on the flukes after 24 h of exposure was found in heartwood ethyl acetate extract of C. siamea (LC50 = 374.30; LC90 = 749.03 ppm), root n-butanol extract of P. zeylanica (LC50 = 1005.12; LC90 = 2411.55 ppm), root hexane, ethyl acetate, and n-butanol extract of P. indica (LC50 = 34.38, 211.34, 506.92; LC90 = 64.09, 496.05, 934.86 ppm), and leaf n-butanol and water extract of T. catappa (LC50 = 487.17, 470.28; LC90 = 913.27, 848.23 ppm). When observed by scanning electron microscopy, the tegument showed similar sequence of morphological changes after treatments with all plant extracts, comprising of swelling of ridges and folds, blebbing, rupturing of the blebs, erosion, lesion and disruption of the tegument. CONCLUSION: This study is the first report on the anthelmintic activity of plant extracts to C. spatiosus; therefore, these plant extracts are highly effective in the elimination of adult rumen flukes.

Development and Optimisation of a Multiresidue Method for the Determination of 40 Anthelmintic Compounds in Environmental Water Samples by Solid Phase Extraction (SPE) with LC-MS/MS Detection.

A comprehensive multiresidue method was developed and validated for the determination of 40 anthelmintic compounds, including 13 transformation products, in surface and groundwater samples at sub nanogram per litre (ng L-1) levels. Anthelmintic residues were extracted from unfiltered water samples using polymeric divinylbenzene solid phase extraction (SPE) cartridges, and eluted with methanol: acetone (50:50, v/v). Purified extracts were concentrated, filtered and injected for UHPLC-MS/MS determination. The method recovery (at a concentration representative of realistic expected environmental water levels based on literature review) ranged from 83-113%. The method was validated, at three concentration levels, in accordance to Commission Decision 2002/657/EC and SANTE/11813/2017 guidelines. Trueness and precision, under within-laboratory reproducibility conditions, ranged from 88-114% and 1.1-19.4%, respectively. The applicability of the method was assessed in a pilot study whereby 72 different surface and groundwater samples were collected and analysed for the determination of these 40 compounds for the first time in Ireland. This is the most comprehensive method available for the investigation of the occurrence of both anthelmintic parent compounds and their transformation products in raw, unfiltered environmental waters.

Quality of albendazole tablets legally circulating in the pharmaceutical market of Addis Ababa, Ethiopia: physicochemical evaluation.

BACKGROUND: Parasitic diseases are the main challenge of livestock production in the world. They are mainly controlled by the use of anthelmintic drugs. To be effective, the drugs should contain the appropriate amount of active pharmaceutical ingredient (API) and have the required physical characteristics. In this study, qualitative and quantitative assessments were performed to evaluate the quality of different brands of albendazole tablets legally circulating in pharmaceutical markets of Addis Ababa, Ethiopia. METHODS: Ultraviolet-Visible Spectroscopy (UVS), Fourier Transform Infrared Spectroscopy (FTIR) and High-Performance Liquid Chromatography (HPLC) were used for identification. Quantitative analysis was performed by HPLC. United States Pharmacopeia standard was used as a control to evaluate the identity and content of the API in the samples. A total of 10 batches of albendazole tablets from six different brands were collected and evaluated. RESULTS: All brands of albendazole tablets, except one, had acceptable physical characteristics. There was gross contamination in one batch, weight variation in 4 (40%) batches, and absence of package insert in 2 (20%) batches. All three methods of evaluation (UVS, FTIR and HPLC) confirmed that all batches passed the identity test. Quantitative analysis showed that no batch had API above the acceptable limit. However, 30% of batches from three different brands contained lower amount of API per tablet than the acceptable limit. CONCLUSIONS: All batches of albendazole circulating in the market in Addis Ababa did not fulfil either physical or chemical quality standards. The most important finding of this research was the presence of drugs with lower level of API than the acceptable limit. This can lead to treatment failure and favour the emergence of parasites that are resistant to drugs. Therefore, there should be a thorough evaluation of drugs before approval. The study also revealed the importance of occasional assessment of drugs circulating even in the legal market.

Restricted Access Volatile Supramolecular Solvents for Single-Step Extraction/Cleanup of Benzimidazole Anthelmintic Drugs in Milk Prior to LC-MS/MS.

In this work, a restricted access volatile supramolecular solvent (RAM-VOL-SUPRAS) directly synthesized in milk is proposed for the first time for the simultaneous extraction and cleanup of benzimidazole anthelmintic drugs in milk meant for human consumption. The RAM-VOL-SUPRAS was formed by the self-assembly and coacervation of hexanol in tetrahydrofuran induced by the water content in milk. Benzimidazoles legislated by the European Union were quantitatively extracted (80-110%), and proteins were precipitated by the action of THF and the amphiphile; extraction of carbohydrates was avoided by a size exclusion mechanism, and lipids were removed during hexanol evaporation. The analytical methodology was fully validated according to Commission Decision 2002/657/EC. Method detection limits from 0.03 to 0.14 µg L-1 were well below the maximum residue limits legislated in milk for these drugs, with interday precisions at maximum residue levels below 13%. This novel methodology guarantees a rapid and reliable tool for daily and routine laboratory analyses in the field of food quality control.

Assessment of the long-acting ivermectin formulation in sheep: Further insight into potential pharmacokinetic interactions.

The aim of the current study was to evaluate the in vivo pharmacokinetic of ivermectin (IVM) after the administration of a long-acting (LA) formulation to sheep and its impact on potential drug-drug interactions. The work included the evaluation of the comparative plasma profiles of IVM administered at a single therapeutic dose (200 µg/kg) and as LA formulation at 630 µg/kg. Additionally, IVM was measured in different gastrointestinal tissues at 15 days posttreatment with both IVM formulations. The impact of the long-lasting and enhanced IVM exposure on the disposition kinetics of abamectin (ABM) was also assessed. Plasma (IVM and ABM) and gastrointestinal (IVM) concentrations were analyzed by HPLC with fluorescent detection. In plasma, the calculated Cmax and AUC0-t values of the IVM-LA formulation were 1.47- and 3.35-fold higher compared with IVM 1% formulation, respectively. The T1/2ab and Tmax collected after administration of the LA formulation were 2- and 3.5-fold longer than those observed after administration of IVM 1% formulation, respectively. Significantly higher IVM concentrations were measured in the intestine mucosal tissues and luminal contents with the LA formulation, and in the liver, the increase was 7-fold higher than conventional formulation. There was no drug interaction between IVM and ABM after the single administration of ABM at 15 days post-administration of the IVM LA formulation. The characterization of the kinetic behavior of the LA formulation to sheep and its potential influence on drug-drug interactions is a further contribution to the field.