ABSTRACT
A simple chromo-fluorogenic chemodosimeter probe, α-benzithiazolyl 3-pyrrolyl BODIPY, was synthesized by reacting α-formyl 3-pyrrolyl BODIPY with 2-aminothiophenol in DMF at reflux under basic conditions. The probe was structurally characterized by X-ray, HR-MS, and 1D & 2D NMR techniques. The X-ray structure revealed that the appended pyrrole was almost in the plane with a small deviation of 12.15° from the 12-atom mean plane of the BF2-dipyrrin core and the benzithiazolyl moiety was also deviated by 18.74° from the BF2-dipyrrin core. The α-benzithiazolyl 3-pyrrolyl BODIPY exhibits one intense absorption band at 608 nm and a less intense band at 412 nm corresponding to the 3-pyrrolyl BODIPY and benzithiazolyl moiety, respectively. The strongly fluorescent probe shows one intense emission band at 637 nm with a quantum yield of 0.48. The probe acted as an exclusive colorimetric and chemodosimetric sensor for CN- ions over other anions with high sensitivity (LOD = 13 nM) and quick response time (10 s) in an aqueous CH3CN medium. The CN- ion attacks the imine group of the benzithiazolyl moiety of 3via a nucleophilic addition reaction and converts the sp2 to sp3 carbon which disrupts the conjugation between the 3-pyrrolyl BODIPY and benzithiazolyl moieties, which is reflected in the clear colour change from red fluorescence to blue fluorescence as well as significant changes in the spectral and electrochemical properties. The detection of cyanide with the probe for biological applications was also performed with plant tissue. DFT/TD-DFT studies were in agreement with the experimental observations.
ABSTRACT
Diethyl chlorophosphate (DCP), an organophosphate, is utilized as a pesticide, herbicide, and for various other applications. Despite many uses of organophosphates, the organophosphates are noxious and harmful substances, and their selective detection is a critical concern in the context of the environment, physiology, and social security. In a methodological quest, here we have synthesized two Schiff base compounds 1 and 2 by introducing the hydroxyl group at the α-position of 3-pyrrolyl BODIPY either directly as hydroxylamine 1 or at the ortho position of aryl ring as 2-aminophenol 2. Both compounds 1 and 2 exhibited high selectivity and high sensitivity for DCP over other pesticides in the aqueous-alcoholic medium at physiological pH. This occurs via nucleophilic phosphorylation of the hydroxyl group, which resulted in both compounds exhibiting two different optical signals following the structure-function correlation of the pyrrolyl BODIPY systems. Upon binding DCP, compound 1 showed a quenching in the optical spectrum because of phosphorylation of hydroxyl group whereas compound 2 exhibited enhancements in both absorption and fluorescence spectra because of hydroxyl phosphorylation followed by intramolecular cyclization. Furthermore, the fluorescent microscopy experiments also indicated that the compound could be used as a fluorescent compound for sensing DCP in plant tissues.
ABSTRACT
In this study, phytoremediation potential of toxic metals like selenium (Se) and lanthanum (La) by transformed hairy roots was investigated and compared with plantlets under in-vitro conditions. Agrobacterium rhizogenes A4RS could induce hairy roots with higher biomass in 5-7 days of infection on in-vitro leaves of Hybanthus enneaspermus. The ICP-OES data indicated that the hairy roots were able to accumulate both selenium and lanthanum efficiently compared to plantlets. The hairy roots and plantlets show optimum absorption at 50 ppm under both individual and combined metal supply. The metal accumulation performances increased by 13.6% (La) and 10.9% (Se) in hairy roots with combined metal supply (La and Se) compared to individual supply (La or Se) conditions. The Se accumulated more than La, but the La accumulation percentage was found to increase substantially under combined metal supply conditions, shows the suitability and potential of hairy roots for phytoremediation of La and Se.
