Hot Spot-Localized Artificial Antibodies for Label-Free Plasmonic Biosensing.

The development of biomolecular imprinting over the last decade has raised promising perspectives in replacing natural antibodies with artificial antibodies. A significant number of reports have been dedicated to imprinting of organic and inorganic nanostructures, but very few were performed on nanomaterials with a transduction function. Herein we describe a relatively fast and efficient plasmonic hot spot-localized surface imprinting of gold nanorods using reversible template immobilization and siloxane co-polymerization. The technique enables a fine control of the imprinting process at the nanometer scale and provides a nanobiosensor with high selectivity and reusability. Proof of concept is established by the detection of neutrophil gelatinase-associated lipocalin (NGAL), a biomarker for acute kidney injury, using localized surface plasmon resonance spectroscopy. The work represents a valuable step towards plasmonic nanobiosensors with synthetic antibodies for label-free and cost-efficient diagnostic assays. We expect that this novel class of surface imprinted plasmonic nanomaterials will open up new possibilities in advancing biomedical applications of plasmonic nanostructures.

Does polysaccharide is an idea template selection for glycosyl imprinting?

A novel glycoprotein imprinting strategy was proposed and was applied to the detection of the carbohydrate antigen 19-9. The glycosylated complex of glycoprotein was used as template to construct a glycosyl imprinted sensor. The eluted imprinted cavities showed good affinity for template glycosyls and glycoproteins carrying template glycosyl. The effect of template saccharide structure on glycosyl imprinted sensors is further discussed. More complex template structures can lead to better sensor performance including selectivity and sensitivity. As a result, the polysaccharide imprinted sensor showed preeminent linear response to CA19-9 in the range of 0.1-5U/mL, with a detection limit of 0.028U/mL (3δ/K), while the linear of the monosaccharide imprinted sensor was 1-60U/mL and the detection limit was 0.17U/mL. The complex structure on the template surface provides more possibilities for the recognition of the template molecules, consequently, led to the significant anti-interference capability of the polysaccharide imprinted sensor. Furthermore, recoveries ranging from 93.0% to 103.5% were achieved when human serum samples were assayed using the polysaccharide imprinted sensor.

From imprinting to microcontact imprinting-A new tool to increase selectivity in analytical devices.

Molecular imprinting technology has been successfully applied to small molecular templates but a slow progress has been made in macromolecular imprinting owing to the challenges in natural properties of macromolecules, especially proteins. In this review, the macromolecular imprinting approaches are discussed with examples from recent publications. A new molecular imprinting strategy, microcontact imprinting is highlighted with its recent applications.