{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,19]],"date-time":"2026-10-19T13:02:31Z","timestamp":1792414951026,"version":"4.4.0"},"update-to":[{"DOI":"10.12688\/wellcomeopenres.20613.1","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2024,8,5]],"date-time":"2024-08-05T00:00:00Z","timestamp":1722816000000}}],"reference-count":62,"publisher":"F1000 Research Ltd","license":[{"start":{"date-parts":[[2024,8,5]],"date-time":"2024-08-05T00:00:00Z","timestamp":1722816000000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010269","name":"Wellcome Trust","doi-asserted-by":"publisher","award":["220211"],"award-info":[{"award-number":["220211"]}],"id":[{"id":"10.13039\/100010269","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["wellcomeopenresearch.org"],"crossmark-restriction":false},"short-container-title":["Wellcome Open Res"],"abstract":"<ns5:p>Background Ivermectin is a widely used drug for the treatment of helminthiasis and filariasis worldwide, and it has also shown promise for malaria elimination through its potent mosquito-lethal activity. The objective of this study was to develop and validate a high-throughput and sensitive method to quantify ivermectin in plasma and whole blood samples, using automated sample extraction followed by liquid chromatography-tandem mass spectrometry (LC-MS\/MS). Methods Phospholipids were removed in patient whole blood (100 \u00b5l) and plasma (100 \u00b5l) samples using a 96-well plate Hybrid-solid phase extraction technique. Ivermectin and its isotope-labelled internal standard (ivermectin-D2) were separated on an Agilent Poroshell 120 EC-C18 50mm \u00d7 3.0mm I.D. 2.7\u00b5m, using a mobile phase of acetonitrile: ammonium formate 2 mM containing 0.5% formic acid (90: 10, v\/v). Detection was performed using a triple quadrupole mass spectrometer in the positive ionization mode. Results The method was validated in the concentration range 0.970 - 384 ng\/ml in both plasma and whole blood matrices. Intra- and inter-batch precisions during the validation were below 15%. There was no carryover or matrix effects detected. Ivermectin is a stable compound and results showed no degradation in the different stability tests. Conclusions The validated method proved to have high sensitivity and precision, good selectivity and to be suitable for clinical application or laboratory quantification of ivermectin in plasma or whole blood samples.<\/ns5:p>","DOI":"10.12688\/wellcomeopenres.20613.2","type":"journal-article","created":{"date-parts":[[2024,8,5]],"date-time":"2024-08-05T12:15:37Z","timestamp":1722860137000},"page":"231","update-policy":"https:\/\/doi.org\/10.12688\/wellcomeopenres.crossmark-policy","source":"Crossref","is-referenced-by-count":2,"title":["Determination of ivermectin in plasma and whole blood using LC-MS\/MS"],"prefix":"10.12688","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3897-7952","authenticated-orcid":false,"given":"Natpapat","family":"Kaewkhao","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Warunee","family":"Hanpithakpong","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4566-4030","authenticated-orcid":false,"given":"Joel","family":"Tarning","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7246-4128","authenticated-orcid":false,"given":"Daniel","family":"Blessborn","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"2560","published-online":{"date-parts":[[2024,8,5]]},"reference":[{"key":"ref-2","doi-asserted-by":"publisher","first-page":"39-52","DOI":"10.1093\/jaoac\/83.1.39","article-title":"Confirmation of eprinomectin, moxidectin, abamectin, doramectin, and ivermectin in beef liver by Liquid Chromatography\/positive ion Atmospheric Pressure Chemical Ionization mass spectrometry.","volume":"83","author":"M Ali","year":"2000","journal-title":"J AOAC Int."},{"key":"ref-3","first-page":"35-42","article-title":"A comparison of the efficacy of single doses of albendazole, ivermectin, and diethylcarbamazine alone or Ascaris and Trichuris spp.","volume":"81","author":"V Belizario","year":"2003","journal-title":"Bull World Health Organ."},{"key":"ref-4","doi-asserted-by":"publisher","first-page":"1175-1185","DOI":"10.1002\/(SICI)1097-0231(19990630)13:12<1175::AID-RCM639>3.0.CO;2-0","article-title":"The effects of sample preparation methods on the variability of the electrospray ionization response for model drug compounds.","volume":"13","author":"R Bonfiglio","year":"1999","journal-title":"Rapid Commun Mass Spectrom."},{"key":"ref-5","doi-asserted-by":"publisher","first-page":"194-214","DOI":"10.1093\/oso\/9780195071702.003.0012","article-title":"11 The genesis of the antiparasitic drug ivermectin.","volume":"10","author":"W Campbell","year":"1992","journal-title":"Inventive Minds: Creativity in Technology."},{"key":"ref-6","doi-asserted-by":"publisher","first-page":"43-49","DOI":"10.1016\/j.vetpar.2018.05.007","article-title":"Field trial assessment of ivermectin pharmacokinetics and efficacy against susceptible and resistant nematode populations in cattle.","volume":"256","author":"C Canton","year":"2018","journal-title":"Vet Parasitol."},{"key":"ref-7","doi-asserted-by":"publisher","DOI":"10.1186\/s12936-017-1801-4","article-title":"Ivermectin to reduce malaria transmission I. Pharmacokinetic and pharmacodynamic considerations regarding efficacy and safety.","volume":"16","author":"C Chaccour","year":"2017","journal-title":"Malar J."},{"key":"ref-8","doi-asserted-by":"publisher","first-page":"113-116","DOI":"10.1086\/653208","article-title":"Effect of ivermectin on Anopheles gambiae mosquitoes fed on humans: the potential of oral insecticides in malaria control.","volume":"202","author":"C Chaccour","year":"2010","journal-title":"J Infect Dis."},{"key":"ref-9","doi-asserted-by":"publisher","first-page":"1841-1852","DOI":"10.4155\/bio-2018-0110","article-title":"A sensitive and selective LC\u2013MS\/MS method for quantitation of ivermectin in human, mouse and monkey plasma: clinical validation.","volume":"10","author":"Y Chhonker","year":"2018","journal-title":"Bioanalysis."},{"key":"ref-10","doi-asserted-by":"publisher","first-page":"212-214","DOI":"10.1016\/0169-4758(92)90267-6","article-title":"Treatment of onchocerciasis with ivermectin in Central America.","volume":"8","author":"E Cupp","year":"1992","journal-title":"Parasitol Today."},{"key":"ref-11","doi-asserted-by":"publisher","first-page":"S100-108","DOI":"10.1016\/j.actatropica.2010.08.009","article-title":"Elimination of human onchocerciasis: history of progress and current feasibility using ivermectin (Mectizan(\u00ae)) monotherapy.","volume":"120 Suppl 1","author":"E Cupp","year":"2011","journal-title":"Acta Trop."},{"key":"ref-12","doi-asserted-by":"publisher","first-page":"S267-S277","DOI":"10.1155\/2010\/249542","article-title":"Quantitative determination of ivermectin in raw milk using positive ESI LC-MS\/MS.","volume":"7","author":"M Dahiya","year":"2010","journal-title":"J Chem."},{"key":"ref-13","doi-asserted-by":"publisher","first-page":"576-580","DOI":"10.1039\/b101164m","article-title":"Development and optimisation of an improved derivatisation procedure for the determination of avermectins and milbemycins in bovine liver.","volume":"126","author":"M Danaher","year":"2001","journal-title":"Analyst."},{"key":"ref-14","doi-asserted-by":"publisher","first-page":"344-345","DOI":"10.1016\/0035-9203(94)90110-4","article-title":"Treatment of Strongyloides stercoralis infection with ivermectin compared with albendazole: results of an open study of 60 cases.","volume":"88","author":"A Datry","year":"1994","journal-title":"Trans R Soc Trop Med Hyg."},{"key":"ref-15","doi-asserted-by":"publisher","first-page":"134-146","DOI":"10.1016\/j.jchromb.2006.11.014","article-title":"Positive and negative electrospray LC\u2013MS\u2013MS methods for quantitation of the antiparasitic endectocide drugs, abamectin, doramectin, emamectin, eprinomectin, ivermectin, moxidectin and selamectin in milk.","volume":"850","author":"D Durden","year":"2007","journal-title":"J Chromatogr B Analyt Technol Biomed Life Sci."},{"key":"ref-16","doi-asserted-by":"publisher","first-page":"18-25","DOI":"10.1016\/j.jpba.2019.04.007","article-title":"Development and validation of an LC-MS\/MS method for the analysis of ivermectin in plasma, whole blood, and dried blood spots using a fully automatic extraction system.","volume":"172","author":"U Duthaler","year":"2019","journal-title":"J Pharm Biomed Anal."},{"key":"ref-1","article-title":"Guideline on bioanalytical method validation.","year":"2012"},{"key":"ref-17","article-title":"Bioanalytical method validation guidance for industry.","year":"2018","journal-title":"US Department of Health and Human Services Food and Drug Administration Center for Drug Evaluation and Research and Center for Veterinary Medicine."},{"key":"ref-18","doi-asserted-by":"publisher","first-page":"1167-1174","DOI":"10.1208\/s12248-014-9644-1","article-title":"Repeat analysis and Incurred Sample Reanalysis: recommendation for best practices and harmonization from the Global Bioanalysis Consortium harmonization team.","volume":"16","author":"E Fluhler","year":"2014","journal-title":"AAPS J."},{"key":"ref-19","first-page":"253-254","article-title":"Efficacy of ivermectin for the treatment of head lice (Pediculosis capitis).","volume":"45","author":"P Glaziou","year":"1994","journal-title":"Trop Med Parasitol."},{"key":"ref-20","doi-asserted-by":"publisher","DOI":"10.1177\/1178633720932544","article-title":"Efficacy of single dose Ivermectin against Strongyloides stercoralis infection among primary school children in Amhara National Regional State.","volume":"13","author":"T Hailu","year":"2020","journal-title":"Infect Dis (Auckl)."},{"key":"ref-21","doi-asserted-by":"publisher","first-page":"891-897","DOI":"10.1016\/j.foodchem.2016.11.077","article-title":"Development and validation of a highly sensitive quantitative\/confirmatory method for the determination of ivermectin residues in bovine tissues by UHPLC-MS\/MS.","volume":"221","author":"O Hoyos","year":"2017","journal-title":"Food Chem."},{"key":"ref-22","doi-asserted-by":"publisher","first-page":"333-343","DOI":"10.1016\/j.jchromb.2008.08.032","article-title":"Monitoring phospholipids for assessment of ion enhancement and ion suppression in ESI and APCI LC\/MS\/MS for chlorpheniramine in human plasma and the importance of multiple source matrix effect evaluations.","volume":"875","author":"O Ismaiel","year":"2008","journal-title":"J Chromatogr B Analyt Technol Biomed Life Sci."},{"key":"ref-25","first-page":"78-83","article-title":"Ivermectin in the treatment of scabies.","volume":"17","author":"I Khan","year":"2016","journal-title":"J Pak Assoc Dermatol."},{"key":"ref-26","doi-asserted-by":"publisher","first-page":"1013-1020","DOI":"10.1016\/j.jpba.2005.08.026","article-title":"Liquid chromatographic assay of ivermectin in human plasma for application to clinical pharmacokinetic studies.","volume":"40","author":"D Kitzman","year":"2006","journal-title":"J Pharm Biomed Anal."},{"key":"ref-27","doi-asserted-by":"publisher","DOI":"10.1186\/s12936-017-2125-0","article-title":"Ivermectin susceptibility, sporontocidal effect, and inhibition of time to re-feed in the Amazonian malaria vector Anopheles darlingi.","volume":"16","author":"K Kobylinski","year":"2017","journal-title":"Malar J."},{"key":"ref-28","doi-asserted-by":"publisher","first-page":"1221-1230","DOI":"10.1002\/cpt.1716","article-title":"Safety, pharmacokinetics, and mosquito\u2010lethal effects of ivermectin in combination with dihydroartemisinin\u2010piperaquine and primaquine in healthy adult Thai subjects.","volume":"107","author":"K Kobylinski","year":"2020","journal-title":"Clin Pharmacol Ther."},{"key":"ref-29","doi-asserted-by":"publisher","first-page":"463-472","DOI":"10.1016\/j.pt.2017.02.004","article-title":"Ivermectin - old drug, new tricks?","volume":"33","author":"R Laing","year":"2017","journal-title":"Trends Parasitol."},{"key":"ref-30","doi-asserted-by":"publisher","first-page":"219-230","DOI":"10.1016\/j.jchromb.2006.02.011","article-title":"Liquid chromatography\u2013mass spectrometry\/mass spectrometry method development for drug metabolism studies: examining lipid matrix ionization effects in plasma.","volume":"833","author":"J Little","year":"2006","journal-title":"J Chromatogr B Analyt Technol Biomed Life Sci."},{"key":"ref-31","doi-asserted-by":"publisher","first-page":"24-29","DOI":"10.1373\/clinchem.2015.238626","article-title":"CLSI C62-A: a new standard for clinical mass spectrometry.","volume":"62","author":"K Lynch","year":"2016","journal-title":"Clin Chem."},{"key":"ref-32","doi-asserted-by":"publisher","first-page":"3019-3030","DOI":"10.1021\/ac020361s","article-title":"Strategies for the assessment of matrix effect in quantitative bioanalytical methods based on HPLC\u2212 MS\/MS.","volume":"75","author":"B Matuszewski","year":"2003","journal-title":"Anal Chem."},{"key":"ref-33","doi-asserted-by":"publisher","first-page":"1478-1486","DOI":"10.1242\/jeb.118570","article-title":"Characterization of the target of ivermectin, the glutamate-gated chloride channel, from Anopheles gambiae.","volume":"218","author":"J Meyers","year":"2015","journal-title":"J Exp Biol."},{"key":"ref-34","doi-asserted-by":"publisher","first-page":"1503-1507","DOI":"10.1016\/j.mex.2018.11.011","article-title":"A quick and simple method for the determination of ivermectin in dog plasma by LC\u2013MS\/MS.","volume":"5","author":"E Morbidelli","year":"2018","journal-title":"MethodsX."},{"key":"ref-35","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pntd.0006020","article-title":"Safety and pharmacokinetic profile of fixed-dose ivermectin with an innovative 18mg tablet in healthy adult volunteers.","volume":"12","author":"J Munoz","year":"2018","journal-title":"PLoS Negl Trop Dis."},{"key":"ref-36","first-page":"848-858","article-title":"High-performance liquid chromatographic method for the determination of ivermectin in plasma.","volume":"37","author":"K Na-Bangchang","year":"2006","journal-title":"Southeast Asian J Trop Med Public Health."},{"key":"ref-101","doi-asserted-by":"publisher","first-page":"426-430","DOI":"10.1038\/clpt.1993.46","article-title":"Protein binding and ivermectin estimations in patients with onchocerciasis.","volume":"53","author":"P Okonkwo","year":"1993","journal-title":"Clin Pharmacol Ther."},{"key":"ref-37","doi-asserted-by":"publisher","first-page":"91-98","DOI":"10.1016\/j.ijantimicag.2007.08.023","article-title":"Ivermectin: 25 years and still going strong.","volume":"31","author":"S Omura","year":"2008","journal-title":"Int J Antimicrob Agents."},{"key":"ref-38","doi-asserted-by":"publisher","first-page":"277-281","DOI":"10.1016\/s0001-706x(01)00162-0","article-title":"Onchocerciasis control in Nigeria: will households be able to afford community-directed treatment with ivermectin?","volume":"80","author":"O Onwujekwe","year":"2001","journal-title":"Acta Trop."},{"key":"ref-39","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0172202","article-title":"Isolation and determination of ivermectin in post-mortem and in vivo tissues of dung beetles using a continuous solid phase extraction method followed by LC-ESI+-MS\/MS.","volume":"12","author":"A Ortiz","year":"2017","journal-title":"PLoS One."},{"key":"ref-40","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pntd.0000998","article-title":"Phenotypic evidence of emerging ivermectin resistance in Onchocerca volvulus.","volume":"5","author":"M Osei-Atweneboana","year":"2011","journal-title":"PLoS Negl Trop Dis."},{"key":"ref-41","first-page":"491-503","article-title":"Strategies and tools for the control\/elimination of lymphatic filariasis.","volume":"75","author":"E Ottesen","year":"1997","journal-title":"Bull World Health Organ."},{"key":"ref-42","doi-asserted-by":"publisher","first-page":"357-365","DOI":"10.1093\/cid\/ciu797","article-title":"Efficacy and safety of the mosquitocidal drug ivermectin to prevent malaria transmission after treatment: a double-blind, randomized, clinical trial.","volume":"60","author":"A Ouedraogo","year":"2015","journal-title":"Clin Infect Dis."},{"key":"ref-43","doi-asserted-by":"publisher","first-page":"639-645","DOI":"10.1016\/s0731-7085(02)00720-3","article-title":"Improved LC method to determine ivermectin in plasma.","volume":"31","author":"J Prieto","year":"2003","journal-title":"J Pharm Biomed Anal."},{"key":"ref-44","doi-asserted-by":"publisher","first-page":"2901-2909","DOI":"10.1039\/C8AY00828K","article-title":"Development and validation of a LC-MS\/MS method for ivermectin quantification in dried blood spots: application to a pharmacokinetic study in Trichuris trichiura-infected adults.","volume":"10","author":"J Schulz","year":"2018","journal-title":"Anal Methods."},{"key":"ref-45","article-title":"Analyst 1.7 software download."},{"key":"ref-46","doi-asserted-by":"publisher","first-page":"29-34","DOI":"10.1016\/j.wem.2013.09.008","article-title":"The use of ivermectin to kill Ixodes scapularis ticks feeding on humans.","volume":"25","author":"J Sheele","year":"2014","journal-title":"Wilderness Environ Med."},{"key":"ref-47","doi-asserted-by":"publisher","first-page":"139-156","DOI":"10.1016\/0304-4017(94)00743-v","article-title":"Structure and activity of avermectins and milbemycins in animal health.","volume":"59","author":"W Shoop","year":"1995","journal-title":"Vet Parasitol."},{"key":"ref-48","doi-asserted-by":"publisher","first-page":"219-227","DOI":"10.1016\/j.jpba.2005.11.006","article-title":"A new approach to evaluate regression models during validation of bioanalytical assays.","volume":"41","author":"T Singtoroj","year":"2006","journal-title":"J Pharm Biomed Anal."},{"key":"ref-50","doi-asserted-by":"publisher","first-page":"388-401","DOI":"10.1002\/cpt.1219","article-title":"Pharmacokinetics-pharmacodynamics of high-dose ivermectin with dihydroartemisinin-piperaquine on mosquitocidal activity and QT-prolongation (IVERMAL).","volume":"105","author":"M Smit","year":"2019","journal-title":"Clin Pharmacol Ther."},{"key":"ref-49","doi-asserted-by":"publisher","first-page":"37-56","DOI":"10.1586\/14787210.7.1.37","article-title":"Prospects for the control of neglected tropical diseases by mass drug administration.","volume":"7","author":"H Smits","year":"2009","journal-title":"Expert Rev Anti Infect Ther."},{"key":"ref-51","first-page":"211-216","article-title":"Veterinary use of ivermectin.","volume":"59","author":"I Sutherland","year":"1990","journal-title":"Acta Leiden."},{"key":"ref-52","doi-asserted-by":"publisher","DOI":"10.1186\/s40249-015-0091-8","article-title":"Nobel prize for the artemisinin and ivermectin discoveries: a great boost towards elimination of the global infectious diseases of poverty.","volume":"4","author":"E Tambo","year":"2015","journal-title":"Infect Dis Poverty."},{"key":"ref-53","doi-asserted-by":"publisher","first-page":"328-334","DOI":"10.1016\/j.clinbiochem.2004.11.007","article-title":"Matrix effects: the Achilles heel of quantitative high-performance liquid chromatography\u2013electrospray\u2013tandem mass spectrometry.","volume":"38","author":"P Taylor","year":"2005","journal-title":"Clin Biochem."},{"key":"ref-54","doi-asserted-by":"publisher","first-page":"15773-15776","DOI":"10.1073\/pnas.1520952112","article-title":"Profile of William C. Campbell, Satoshi \u014cmura, and Youyou Tu, 2015 Nobel Laureates in Physiology or Medicine.","volume":"112","author":"W Van Voorhis","year":"2015","journal-title":"Proc Natl Acad Sci U S A."},{"key":"ref-55","doi-asserted-by":"publisher","first-page":"2026-2034","DOI":"10.1093\/cid\/cix616","article-title":"Macrofilaricidal efficacy of repeated doses of ivermectin for the treatment of river blindness.","volume":"65","author":"M Walker","year":"2017","journal-title":"Clin Infect Dis."},{"key":"ref-56","doi-asserted-by":"publisher","first-page":"395-398","DOI":"10.1007\/s00128-009-9638-3","article-title":"Rapid method for multi-residue determination of avermectins in bovine liver using high-performance liquid chromatography with fluorescence detection.","volume":"82","author":"H Wang","year":"2009","journal-title":"Bull Environ Contam Toxicol."},{"key":"ref-57","doi-asserted-by":"publisher","DOI":"10.1201\/9780203756621","article-title":"Essential malariology (4th ed.)","author":"D Warrell","year":"2002"},{"key":"ref-100","article-title":"Web annex A. World Health Organization model list of essential Medicines \u2013 23rd list, 2023."},{"key":"ref-58","doi-asserted-by":"publisher","first-page":"1247-1255","DOI":"10.1093\/cid\/ciy246","article-title":"Efficacy and safety of ivermectin against Trichuris trichiura in preschool-aged and school-aged children: a randomized controlled dose-finding trial.","volume":"67","author":"D Wimmersberger","year":"2018","journal-title":"Clin Infect Dis."},{"key":"ref-59","doi-asserted-by":"publisher","first-page":"2125-2138","DOI":"10.1002\/rcm.4121","article-title":"Phospholipids in liquid chromatography\/mass spectrometry bioanalysis: comparison of three tandem mass spectrometric techniques for monitoring plasma phospholipids, the effect of mobile phase composition on phospholipids elution and the association of phospholipids with matrix effects.","volume":"23","author":"Y Xia","year":"2009","journal-title":"Rapid Commun Mass Spectrom."},{"key":"ref-60","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0118818","article-title":"Using visualized matrix effects to develop and improve LC-MS\/MS bioanalytical methods, taking TRAM-34 as an example.","volume":"10","author":"J Ye","year":"2015","journal-title":"PLoS One."},{"key":"ref-61","doi-asserted-by":"publisher","first-page":"75-85","DOI":"10.1016\/S0021-9673(00)00466-0","article-title":"Liquid chromatographic determination of emamectin, milbemectin, ivermectin and abamectin in crops and confirmation by liquid chromatography-mass spectrometry.","volume":"896","author":"K Yoshii","year":"2000","journal-title":"J Chromatogr A."},{"key":"ref-62","doi-asserted-by":"publisher","first-page":"1839-1844","DOI":"10.4155\/bio-2017-0214","article-title":"Matrix effects and application of matrix effect factor.","author":"W Zhou","year":"2017","journal-title":"Bioanalysis."}],"container-title":["Wellcome Open Research"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/wellcomeopenresearch.org\/articles\/9-231\/v2\/xml","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/wellcomeopenresearch.org\/articles\/9-231\/v2\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/wellcomeopenresearch.org\/articles\/9-231\/v2\/iparadigms","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,9,30]],"date-time":"2024-09-30T14:10:10Z","timestamp":1727705410000},"score":1,"resource":{"primary":{"URL":"https:\/\/wellcomeopenresearch.org\/articles\/9-231\/v2"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,8,5]]},"references-count":62,"URL":"https:\/\/doi.org\/10.12688\/wellcomeopenres.20613.2","relation":{"has-version":[{"id-type":"doi","id":"10.12688\/wellcomeopenres.20613.1","asserted-by":"subject"}],"has-review":[{"id-type":"doi","id":"10.21956\/wellcomeopenres.25164.r92169","asserted-by":"subject"},{"id-type":"doi","id":"10.21956\/wellcomeopenres.25164.r98725","asserted-by":"subject"},{"id-type":"doi","id":"10.21956\/wellcomeopenres.25164.r92169","asserted-by":"object"},{"id-type":"doi","id":"10.21956\/wellcomeopenres.25164.r98725","asserted-by":"object"}]},"ISSN":["2398-502X"],"issn-type":[{"value":"2398-502X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,8,5]]},"assertion":[{"value":"Indexed","URL":"https:\/\/wellcomeopenresearch.org\/articles\/9-231\/v2#article-reports","order":0,"name":"referee-status","label":"Referee status","group":{"name":"current-referee-status","label":"Current Referee Status"}},{"value":"10.21956\/wellcomeopenres.22816.r85067, Daryl J. Murry, Mamunur Rashid, Pharmacy Practice and Science, University of Nebraska Medical Center, Omaha, Nebraska, 20 Jun 2024, version 1, 2 approved with reservations","URL":"https:\/\/wellcomeopenresearch.org\/articles\/9-231\/v1#referee-response-85067","order":0,"name":"referee-response-85067","label":"Referee Report","group":{"name":"article-reports","label":"Article Reports"}},{"value":"<b>Natpapat Kaewkhao<\/b>; \n<i>Posted: 18 Jul 2024<\/i>; \n<b>Reviewer 1: Comments<\/b> \n<b>1. The advantage of this method over existing approaches should be further discussed.<\/b> I have addressed this point in the revised version by adding a more detailed discussion on the advantages of this method over existing approaches in the section of \u201cResults &amp; discussion: Method Validation\u201d at paragraph 3 and 4.  \n<b>2. Why did the author estimate Ivermectin in plasma if ivermectin is accumulates in red blood cells, as the author discussed in the conclusion?<\/b> Apologies for this misunderstanding. Actually, ivermectin do not accumulate in red blood cells, and is found at higher concentrations in plasma compared to whole blood. We have adjusted the text in \u201cConclusions\u201d to clarify the statement about hemoglobin-binding to the extraction plate. \u201cThe Hybrid SPE &reg;Plus extraction proved to effectively adsorb blood components such as hemoglobin from whole blood samples without the loss of ivermectin.\u201d We also added text and a reference in the end of the discussion section, referencing the distribution of ivermectin into blood and plasma.  \n<b>3. It is unclear why the QC experiment was conducted at 4.64 (low), 56.4 (medium), and 524.0 (high) ng\/mL, whereas the upper limit of quantification of calibration is 384 ng\/mL?<\/b> We thank the reviewer for discovering this typo in the submitted document. The correct concentrations of three QC levels has been specified in the revised version.  \n<b>4. Why did the author suddenly switch the mobile phase from 100 % to 0 % within 1 minute in the LC-MS\/MS gradient system? Is one minute enough for the column to separate the analytes? There is no gradient in this LC method. Please describe the gradient and time needed to re-equilibrate the bioanalytical column.<\/b> The elution of ivermectin is performed under isocratic conditions (mobile phase A) during the first 2.1 minutes. However, a washout step (mobile phase B, 2.1-3.1 min) was also implemented to remove any residual compounds. The program then return to isocratic conditions using only mobile phase A for the remaining time (3.1 \u2013 5.0 min), which is enough to equilibrate the column before the next injection. &nbsp;  \n<b>5. How did the author process the whole blood samples after freezing them at -80&deg;C? explain briefly in the manuscript. Does blood become normal, or is there any clumping or lysis after freezing at -80&deg;C?<\/b> We have addressed this point in the revised version by adding a more detailed description in section \u201cMethods: Sample preparation\u201d.  \n<b>6. The inclusion of a RBC portioning study to evaluate the Ivermectin partitioning between RBC and plasma should be included.<\/b> As the clinical studies were conducted as a collaboration, we did not have direct input in the planning or execution of the clinical studies. Also, one study collected plasma samples while the other study collected whole blood, but none of them collected both. However, we have added information from other publications that explore the differences between ivermectin concentrations in plasma and whole blood.  \n<b>7. It is recommended that the author also include the plasma concentration versus time profile in the manuscript.<\/b> We would like to comply with the reviewer\u2019s request. However, the pharmacokinetic evaluation will be published elsewhere, within the main study paper. Instead, we have chosen to present the method performance of the QC data as this demonstrates the appropriateness of the developed assay for the intended purpose. We have also added this information to the \u201cClinical Applicability\u201d section in the \u201cResults and Discussion\u201d.","URL":"https:\/\/wellcomeopenresearch.org\/articles\/9-231\/v2#referee-comment-5735","order":1,"name":"referee-comment-5735","label":"Referee Comment","group":{"name":"article-reports","label":"Article Reports"}},{"value":"10.21956\/wellcomeopenres.25164.r92169, Helgi Jung-Cook, Universidad Nacional Aut\u00f3noma de M\u00e9xico, Mexico City, 21 Sep 2024, version 2, indexed","URL":"https:\/\/wellcomeopenresearch.org\/articles\/9-231\/v2#referee-response-92169","order":2,"name":"referee-response-92169","label":"Referee Report","group":{"name":"article-reports","label":"Article Reports"}},{"value":"10.21956\/wellcomeopenres.25164.r98725, Vieyle Cortez, Universidad de Alicante, Alicante, 30 Sep 2024, version 2, indexed","URL":"https:\/\/wellcomeopenresearch.org\/articles\/9-231\/v2#referee-response-98725","order":3,"name":"referee-response-98725","label":"Referee Report","group":{"name":"article-reports","label":"Article Reports"}},{"value":"This work was supported by Wellcome [220211, <a href=https:\/\/doi.org\/10.35802\/220211>https:\/\/doi.org\/10.35802\/220211<\/a>]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.","order":4,"name":"grant-information","label":"Grant Information"},{"value":"This is an open access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.","order":0,"name":"copyright-info","label":"Copyright"}]}}