A sensitive dual mode turn-on fluorescence and colorimetric nanosensor for ultrasensitive detection of trace amount of gluten proteins in bread products based on crystalline nano cellulose and gold nanoparticles.

In this work, Gold nanoparticles (AuNPs) encapsulated in the surface of crystalline nano cellulose grafted poly citric acid (CNC-g-PCA) and CNC-g-PCA/Au nanocomposite were synthesized successfully that exhibited stable and intense fluorescence property in aqueous buffer. A dual-mode nanosensor is reported with both colorimetric and fluorimetric readout based on citrate-protected AuNPs for discriminative detection of gluten proteins. The proposed sensing system consists of AuNPs and fluorescent CNCs, where CNCs function as a fluorimetric reporter and AuNPs serve a dual function as a colorimetric reporter and fluorescence quencher.

Rapid Detection and Determination of Scopolamine in the Leaf Extract of Black Henbane (Hyoscyamus niger L.) Plants Using a Novel Nanosensor.

Background: Scopolamine is among the most essential tropane alkaloids used to remedy various nervous system disorders such as urinary incontinence, motion sickness, and spasmodic movements because of its anticholinergic and antispasmodic effects.

Objective: In this study, an optical nanosensor was fabricated using nano-Dragendorff's reagent to detect and determine scopolamine in different plant parts at different stages of growth.

Method: For fabrication of the sensing phase, GO-g-PCA/DR was synthesized by encapsulation of Dragendorff's reagent (DR) on the graphene oxide grafted with poly citric acid (GO-g-PCA) with ultrasonication for 15 min and stirred for 80 min at room temperature, and then it was immobilized on a triacetyl cellulose membrane.