No abstract

A simple pyrimidine-based fluorescent probe (R)-4-(anthracen-9-yl)-6- (naphthalen-1-yl)-1,6-dihydropyrimidine-2-amine (ANDPA) was synthesized through the greener one pot reaction and characterized by IR, NMR, and ESI-Mass. Glucose stabilized silver nanoparticles (Glu-AgNPs) were also synthesized and characterized using UV, IR, XRD, SEM, and TEM. When ANDPA was tagged with Glu-AgNPs, the fluorescent intensity of ANDPA decreased drastically. When the monoclonal antibody (Ab) [immunoglobulin G (IgG)] of Pseudomonas aeruginosa (PA) was attached with ANDPA/Glu-AgNPs, the original intensity of the probe was recovered with minimal enhancement at 446 nm. On further attachment of PA with ANDPA/Glu-AgNPs/PA, the fluorescence intensity of the probe was enhanced obviously at 446 nm with red shift. This phenomenon was further supported by SEM and TEM. The linear range of detection is from 8 to 10 CFU/mL, and LOD is 1.5 CFU/mL. The immunosensor was successfully demonstrated to detect Pseudomonas aeruginosa in water, soil, and food products like milk, sugar cane, and orange juices.

First, a simple and highly emissive fluorescent chalcone ( E)-3-(pyren-2-yl)-1-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (PTP) was synthesized via simple shaking along with an excellent quantum yield of 0.85, and proved as a stable, highly sensitive, and selective biosensor for creatinine. Owing to its unique photophysical interaction with creatinine through Michael adduct formation, PTP was utilized as a Chemodosimeter for the selective recognition of creatinine in blood serum. Under optimized conditions, a broad range of creatinine detection was achieved  from 0.00000113 mg/dL to 15.8 mg/dL along with an excellent limit of detection of 0.00000065 mg/dL (0.058 nM). This biosensor is highly reproducible even for different concentration levels of creatinine. It is the very first creatinine biosensor possessing a wider linear range for clinical applications for creatinine. To ensure its clinical application, blood serum samples of people of different age groups were collected from Alpha Hospital and analyzed for creatinine by using our chemodosimeter method and compared with data obtained using a commercial method in the Alpha hospital. Our data show very good agreement with clinical data. Because clinical protocol involves trienzymes and tedious sample preparation, no doubt, our chemodosimeter will be a cheap and sensitive option compared to the existing clinical methods.

This study mainly focuses on the electrochemical-assisted synthesis of conducting polymers such as polypyrrole (PPy) with sodium dodecyl sulfate (SDS) as a surfactant and supported with functionalized multi-walled carbon nanotubes (f-MWCNTs).

A one-pot greener methodology has been adopted for the synthesis of a simple 4 H -chromene core-based fluorescent tag of ( S )-2-amino-4-(anthracen-9-yl)-7-hydroxy-4 H -chromene-3-carbonitrile (AHC), and its structure has been analyzed using NMR spectroscopy. The physicochemical properties of AHC were well-studied by UV–vis and fluorescent spectroscopy techniques. As a result of excellent emitting property (ϕ ≈ 0.75), it has been coupled with anti-AH through amide linkage, and the AHC-tagged anti-AH has been used as an immunoassay for the selective detection of Aeromonas hydrophila in the presence of interfering pathogens. Under optimized conditions, immunosensors could successfully quantify A. hydrophila from 4 to 736 CFU/mL, and the LOD was 2 CFU/mL. Saliently, the immunoassay has been successfully demonstrated for the analysis of A. hydrophila in the organs of Oreochromis mossambicus fingerlings, and results have shown a very good agreement with our optimized neat AH fluorimetric titration results.