Nano- and femtosecond UV laser pulses to immobilize biomolecules onto surfaces with preferential orientation

Abstract

By relying on the photonic immobilization\ud technique of antibodies onto surfaces, we realized portable\ud biosensors for light molecules based on the use of quartz\ud crystal microbalances, given the linear dependence of the\ud method on the laser pulse intensity. Here, we compare the\ud quality of the anchoring method when using nanosecond\ud (260 nm, 25 mJ/pulse, 5 ns, 10 Hz rep. rate) and femtosecond\ud (258 nm, 25 lJ/pulse, 150 fs, 10 kHz rep. rate) laser\ud source, delivering the same energy to the sample with the\ud same average power. As a reference, we also tethered\ud untreated antibodies by means of the passive adsorption. The\ud results are striking: When the antibodies are irradiated with\ud the femtosecond pulses, the deposition on the gold plate is\ud much more ordered than in the other two cases. The effects\ud of UV pulses irradiation onto the antibodies are also analyzed\ud by measuring absorption and fluorescence and suggest\ud the occurrence of remarkable degradation when nanosecond\ud pulses are used likely induced by a larger thermal coupling.\ud In view of the high average power required to activate th

Simple and Flexible Model for Laser-Driven Antibody–Gold Surface Interactions: Functionalization and Sensing

“…This results in the formation of free, reactive thiol groups that will form covalent bonds with thiol reactive surfaces such as gold . It should be stressed that in the present irradiation condition when using fs laser UV pulses of 25 μJ/pulse, 60 s irradiation time, and 250 mW average power, we carefully checked that antibodies are not degraded, but rather they are only efficiently photoactivated with no effect on the capability of catching the antigene. Among the triads of the entire molecule, i.e., the disulfide bridges having an aromatic residue located nearby, we choose to position the effective laser-induced excitation in the top part of the antibody “leg”, below the molecule hinges, not far from the interconnection between variable and constant domains where triads could be more solvent-accessible.…”

Paper-Based Electrochemical Biosensors for Food Safety Analysis

“…Furthermore, the use of a novel class of 2D nanomaterials is promising in e-PAD biosensor development, such as the hybrids of MoS 2 /graphene [ 72 ], carbon dots [ 73 ], and other innovative nanomaterials that were recently developed in biosensing applications. A further improvement to increase e-PAD biosensor performance and sensitivity could be achieved by the implementation of the photonic immobilization technique, such as nanosecond and femtosecond laser pulses of antibodies onto surfaces [ 74 ] that could also be applied for other biomolecules.…”

Eu-Chelate Polystyrene Microsphere-Based Lateral Flow Immunoassay Platform for hs-CRP Detection

“…Thus, the amplified fluorescence signal may be obtained through optimizing modified probe (e.g., antibody) density [ 22 , 23 ]. The femtosecond pulsed UV radiation source-based photonic immobilization technique (PIT) can effectively improve the binding ability of the antibody, while reducing the degeneration of biomolecules affected by UV light [ 24 ], which is expected to achieve the regulation of probe density but may be limited by the high requirements of operation and equipment. Hence, optimization of EuPSM-based LFIA based on simpler and more effective ways is still needed to meet the requirements of ultra-sensitive POCT platform.…”