Hydrogel Microparticles as Sensors for Specific Adhesion: Case Studies on Antibody Detection and Soil Release Polymers

Abstract

Adhesive processes in aqueous media play a crucial role in nature and are important for many technological processes. However, direct quantification of adhesion still requires expensive instrumentation while their sample throughput is rather small. Here we present a fast, and easily applicable method on quantifying adhesion energy in water based on interferometric measurement of polymer microgel contact areas with functionalized glass slides and evaluation via the Johnson-Kendall-Roberts (JKR) model. The advantage of the method is that the microgel matrix can be easily adapted to reconstruct various biological or technological adhesion processes. Here we study the suitability of the new adhesion method with two relevant examples: (1) antibody detection and (2) soil release polymers. The measurement of adhesion energy provides direct insights on the presence of antibodies showing that the method can be generally used for biomolecule detection. As a relevant example of adhesion in technology, the antiadhesive properties of soil release polymers used in today's laundry products are investigated. Here the measurement of adhesion energy provides direct insights into the relation between polymer composition and soil release activity. Overall, the work shows that polymer hydrogel particles can be used as versatile adhesion sensors to investigate a broad range of adhesion processes in aqueous media.

Radial profile detection of multiple spherical particles in contact with interacting surfaces

“…The method we present relies on knowledge of a very specific use-case, but with a broad applicability in science and engineering. For example, the method may be applicable to physiochemical interactions of soft hydrogel particles and mimics of living cells with interacting surfaces [22], determination of protein adsorption energies on materials surfaces [23] or biosensing approaches [15, 16, 18]. Naturally, a solution based on a more general and re-usable approach would be preferred, however many such approaches we examined lead to noisy results or miss profile occurrences.…”

Microfluidics-assisted synthesis and functionalization of monodisperse colloidal hydrogel particles for optomechanical biosensors

“…Grafting of crotonic acid (Sigma Aldrich, US) was conducted as described earlier. 10,22,30 In short, water was exchanged by 10 mL ethanol, then 250 mg benzophenone (1.4 mmol, Sigma Aldrich, US) and 1.5 g crotonic acid (17 mmol) were added. Subsequently, the mixture was flushed with nitrogen for 30 s before irradiating with UV light for 900 s. The resulting SCP particles were then washed with ethanol and PBS three times each.…”

Quantifying Thermoswitchable Carbohydrate‐Mediated Interactions via Soft Colloidal Probe Adhesion Studies

“…SCPs were synthesized by crosslinking a dispersion of the macromonomer poly(ethylene glycol diacrylamide) (PEGdAAm) in aqueous solution as previously described. [ 56 ] Sodium sulfate (1.42 g, 0.01 mol) was dissolved in 10 mL water. The photoinitiator Irgacure 2959 (2.1 mg, 5.4 µmol) and PEGdAAm ( M n = 8000 Da) (50 mg, 6.3 µmol) were added followed by vigorous shaking.…”