Development, validation, and application of an HPLC method combined with an in vitro model for the determination of antibiotic binding to the haemoadsorber Cytosorb®

Kenda, Sara (author), Gubenšek, Jakob (author), Vovk, Tomaž (author)

Supportive therapy with haemoadsorption is gaining popularity in critically ill patients, with the aim of reducing overinflammation triggered by the cytokine storm. The haemoadsorbers used are not specific for cytokines and also bind antibiotics. The aim of this study was to develop and validate a simple analytical method for the simultaneous determination of selected antibiotics and to develop an in vitro model for the quantification of their binding to the CytoSorb® haemoadsorber under conditions simulating sepsis. Imipenem (IMI), amoxicillin (AMO), cefepime (CEF), meropenem (MERO), vancomycin (VAN) and piperacillin (PIP) were measured in bovine plasma via precipitation with acetonitrile and liquid–liquid extraction with dichloromethane. The aqueous phase was collected and analysed using a C18 HPLC system under gradient conditions, with modulation of organic solvent content and mobile phase pH, and detection performed using a UV/Vis detector. The method was linear (r$^2$2 > 0.982) across investigated analytical ranges (1.0–100.0 µg/mL for AMO and VAN, 1.0–75.0 µg/mL for CEF, MERO and PIP and 2.5–100.0 µg/mL for IMI). Intra- and inter-day precision did not exceed 14% and accuracy ranged from 85.8% to 108.5%. Using the in vitro model, we showed that CytoSorb® significantly removed VAN and PIP, but not MERO. Further clinical studies are needed to establish the clinical significance of these findings and their impact on antibiotic exposure.

• Language: English
• Keywords: antibiotics, critically ill, CytoSorb®, gradient elution, haemoadsorption, hemoadsorption, in vitro model
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FFA - Faculty of Pharmacy; MF - Faculty of Medicine
• Publication status: Published
• Publication version: Version of Record
• Year: 2026
• Number of pages: 14 str.
• Numbering: Vol. 31, iss. 13, art. 2337
• PID: 20.500.12556/RUL-184399
• UDC: 61+615.33
• ISSN on article: 1420-3049
• DOI: 10.3390/molecules31132337
• COBISS.SI-ID: 283660803
• Publication date in RUL: 06.07.2026

Record is a part of a journal

• Title: Molecules
• Shortened title: Molecules
• Publisher: MDPI
• ISSN: 1420-3049
• COBISS.SI-ID: 18462981

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: antibiotiki, kritično bolni, CytoSorb®, gradientna elucija, hemoadsorpcija, hemoadsorpcija, model in vitro, citokini, antibiotiki

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P1-0189
• Name: Farmacevtska tehnologija: od dostavnih sistemov učinkovin do terapijskih izidov zdravil pri otrocih in starostnikih

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P3-0323
• Name: Ledvične bolezni in nadomestna zdravljenja