Functional nanothin films plasma-deposited from 2-isopropenyl-2-oxazoline for biosensor applications

Abstract

Plasma polymers derived from oxazoline precursors present a range of versatile properties that is fueling their use as biomaterials. However, coatings deposited from commonly used methyl and ethyl oxazoline precursors can be sensitive to the plasma deposition conditions. In this work, we used various spectroscopic methods (ellipsometry, x-ray photoelectron spectroscopy, and time of flight secondary ion mass spectrometry) and cell viability assays to evaluate the transferability of deposition conditions from the original plasma reactor developed by Griesser to a new wider, reactor designed for upscaled biosensors applications. The physicochemical properties, reactivity, and biocompatibility of films deposited from 2-isopropenyl-2-oxazoline were investigated. Thanks to the availability of an unsaturated pendant group, the coatings obtained from this oxazoline precursor are more stable and reproducible over a range of deposition conditions while retaining reactivity toward ligands and biomolecules. This study identified films deposited at 20 W and 0.012 mbar working pressure as being the best suited for biosensor applications.

Plasma Deposited Polyoxazoline Films Integration Into Spiral Microfluidics for the Targeted Capture of Size Selected Cells

“…MePOx and PiPOx films were deposited for 30 and 50 s with a plasma ignition power of 20 W and a monomer working pressure of 1.2 × 10 −1 mbar, according to established protocols ( Chan K. M. et al, 2020 ). The thickness of the untreated films ranged from 6.6 to 11.5 nm, increasing with both deposition time and monomer size.…”

“…Deposition of plasma polymers was carried out in a custom-made reactor that has been previously described previously ( Chan K. M. et al, 2020 ). The plasma was ignited with a 13.56 MHz Radio Frequency generator coupled to a matching network (Coaxial Power System).…”

“…Building on this discovery, immunosensing substrates were developed using PPOx to immobilise cancer specific antibodies for application in non-invasive diagnostic devices. The biocompatibility of the films has been previously investigated using both non-cancerous and cancerous prostatic cell lines, fibroblasts, and bladder carcinoma cell lines ( Chan K. M. et al, 2020 ). Cell viability was determined through a resazurin assay and the results showed that PPOx films are biocompatible.…”

Plasma Deposited Polyoxazoline Thin Films for the Biofunctionalization of Electrochemical Sensors

“…Plasma polymer deposition was performed in a custom‐made reactor described previously. [ 32 ] The plasma was ignited using a 13.56 MHz Radio Frequency generator coupled to a matching network (Coaxial Power System). The substrates were introduced in the reactor and primed with air plasma (30W, 3min 1.2 × 10 −1 mbar).…”

Selective Microfluidic Capture and Detection of Prostate Cancer Cells from Urine without Digital Rectal Examination

“…The three plasma deposited polyoxazoline (PPOx)-coated microchannels of each polymethyl methacrylate (PMMA) chip were set as test, negative control, and positive control, respectively. The positive control channel was used as is, with the biocompatible PPOx surface allowing the non-specific attachment of all cell types [ 22 ]. The test channel was biofunctionalized with 60 µL of anti-PSMA antibodies (10 µg mL −1 ).…”