Correlation between spectroscopic and stoichiometric protein to lipid ratios in erythrocyte-derived extracellular vesicles and nanoerythrosomes

Sep 30, 2026

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Erythrocyte-derived extracellular vesicles (RBCEVs) and nanoerythrosomes (NERYs) originate from the same cellular source, enabling their use as related nanocarriers. Increasing the incorporated saturated lipid DPPC at weight ratios up to an order of magnitude drives distinct morphological and structural transitions: standalone nanoerythrosomes form, while RBCEVs show reduced DPPC integration and aggregation. Spectroscopic signals vary quasi-proportionally with spectroscopic protein-to-lipid ratios, establishing a linear correlation to stoichiometric ratios across both systems. Using ATR-FTIR carbonyl and CH vibration-based measurements, approximate lipid concentration can be inferred without lipid-specific analytical assays.

LanguageEnglish

CategoryResearch & Report

FormatPDF

Pages13

Reading Time33 min

AccessFree to download

Introduction

Erythrocyte-derived vesicle systems

Need for rapid, label-free characterization

Methods and Spectroscopy Focus

ATR-FTIR and Raman for protein-lipid ratios

[www. nature.com/scientificreports](www. nature.com/scientificreports) OPEN Correlation between spectroscopic and stoichiometric protein to lipid ratios in erythrocytederived extracellular vesicles and nanoerythrosomes Attila Bóta1􀀍, Kinga Ilyés1, Heinz Amenitsch2, Zoltán Varga1 & Judith Mihály1,3􀀍 The erythrocyte-derived extracellular vesicles and nanoerythrosomes show high similarities due to their same origins supporting their prosperous applicability for new generations of nanocarrier systems. By the addition of a representant erythrocyte-membrane lipid which is the saturated dipalmitoyl-phosphocholine (DPPC), different morphological and structural changes occurred in function of the increasing DPPC ratio. The integration of guest DPPC molecules, expressed in weight ratio extending to an order of magnitude, yields the formation of standalone nanoerythrosomes (NERYs), while the integration of DPPC molecules is significantly reduced into red blood cell derived extracellular vesicles (RBCEVs) causing aggregations ofthese EVs. Despite the induced severe and different changes in morphological and structural characteristics, both systems show systematic changes in spectroscopical signals displaying quasi proportional alterations in their spectroscopical protein to lipid ratios. Sample series with controlled different amount of added lipid (DPPC) provide the observance of the correlation between spectroscopic and stoichiometric protein to lipid ratios. Independently from the selected spectroscopic lipid-determination (regarding to carbon-hydrogen and carbonyl vibrations), a linear relationship was observed between the spectroscopic and stoichiometric ratios in both erythrocyte systems (NERYs, RBCEVs) and the determination of an approximative lipid concentration comes to be possible without any lipid analytic. The majority of the human cells are the micrometre-sized respiratory gas transporter erythrocytes1–3. The interfacial region of these red blood cells (RBCs) disposes of all chemical components of structural and organizational units, membrane complexes which are necessary for long circulation, transport, and cell communications in the fluid blood tissues4,5. The circulating bioreactor erythrocytes permanently inspire the elaboration of new sensor or drug delivery systems for medical purposes, where the active guest molecules are encapsulated into the erythrocytes or attached to their outer surface6–9. Essentially, the cell-membrane of erythrocytes assure the proper biological, chemical and physical functions, therefore their membrane derived vesicle-like particles have turned into the focus of pharmaceutical-medical interest10, 11. The erythrocyte-derived double lipid-walled vesicle-like objects are represented by natural red blood cell extracellular vesicles (RBCEVs) and artificial nanoerythrosomes (NERYs) . The red blood cells produce multivesicular bodies (MVBs) in their one - two-day maturation period from reticulocytes to erythrocytes, then extracellular vesicles (RBCEVs) are released permanently during their 120-day lifespan via shedding of cell membranes12, 13. The extracellular vesicles may contain further substances depending on normal and abnormal conditions differently14–17. Consequently, the determination of all characteristic RBCEV components ─ belonging to carbohydrates, nucleic acids, proteins, lipids, and their metabolic derivates ─ is of paramount importance and recommended in guidelines for extracellular vesicle 1Research Centre for Natural Sciences, Institute of Materials and Environmental Chemistry, Biological Nanochemisry Research Group, Magyar tudósok körútja 2, Budapest 1117, Hungary. 2Austrian SAXS beamline@ELETTRA, Are Science Park 34149 Basovizza TS, Trieste, Italy and Inorganic Chemistry, Graz University of Technology, Stremayrgasse 9, Trieste, Italy. 3Department of Chemistry, Eszterházy Károly Catholic University, Leányka utca 12, Eger 3300, Hungary. 􀀍 email: [bota.attila@ttk.hu](bo

FAQs

How does increasing DPPC affect nanoerythrosomes and extracellular vesicles?

Raising the DPPC incorporation ratio produces different structural outcomes: it enables formation of standalone nanoerythrosomes while reducing DPPC integration into RBCEVs, leading to aggregation of these EVs.

What relationship is observed between spectroscopic and stoichiometric protein-to-lipid ratios?

Across both NERYs and RBCEVs, spectroscopic protein-to-lipid ratios show systematic, quasi-proportional changes that align with stoichiometric ratios, yielding a linear relationship.

Why is ATR-FTIR important in this study?

The work highlights ATR-FTIR as a rapid, non-destructive, label-free approach that uses characteristic absorption bands from protein and lipid components to determine their ratios.

Sep 30, 2026

Upload by Jake