Liposome-metal nanoparticle based sensing systems for (bio)analytical applications

Liposome-metal nanoparticle (MeNP) hybrids have emerged as promising platforms for biosensing due to their low toxicity, enhanced stability, and ability to improve selectivity and signal amplification. This review comprehensively explores the state-of-the-art applications of these hybrid systems in the (bio)analytical domain. Depending on the particular bioassay, MeNPs can be strategically positioned within liposomes in three distinct regions: encapsulated in the aqueous core, embedded in the lipid bilayer, or attached to the phospholipid membrane surface. These configurations enable MeNP-liposome hybrids to operate as (i) signal-generating labels, (ii) carriers for bioreagents, (iii) entities for target sequestration or interference mitigation, and (iv) signal readout amplification. We delve into various analytical applications based on the signal transduction system, including electrochemistry, fluorescence, colorimetry, electrochemiluminescence, photoelectrochemistry, surface plasmon resonance, and surface-enhanced Raman spectroscopy. Representative examples from the last decade illustrate the diverse and innovative uses of these composite materials in the field of biosensing.