Nanodot zirconium trisulfide modified conducting thread: A smart substrate for fabrication of next generation biosensor.

In present work, we report an eco-friendly, flexible and highly conducting cotton thread (CT) as a smart substrate for the development of biosensing platform towards ultrasensitive detection of swine flu serum amyloid A (SAA) biomarker. The biosensor was fabricated by optimized coating of CT with poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) conductive ink followed by incorporation of nanodot zirconium trisulfide (nZrS3) which helped in enhancing the electrochemical properties and improving stability of PEDOT:PSS polymeric film. The fabricated nZrS3/PEDOT:PSS/CT electrode was then used for sequential immobilization of monoclonal antibodies of SAA (anti-SAA) and bovine serum albumin (BSA). The synthesized nanomaterials and fabricated electrodes were characterized through X-ray diffraction, Fourier-transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy and contact angle analyser techniques. The electrochemical response of the fabricated smart thread based biosensor (BSA/anti-SAA/ZrS3/PEDOT:PSS/CT) was recorded against SAA using chronoamperometry technique which revealed superior sensitivity {30.2 µA [log (µg mL-1)]-1 cm-2}, excellent lower detection limit (0.72 ng mL-1) and prolonged shelf life up to 48 days. The response of the biosensor was also validated by analysing the electrochemical response of SAA spiked serum samples and the obtained results showed good correlation with that of standard samples.

Noscapine-Amino Acid Conjugates Suppress the Progression of Cancer Cells.

Lung cancer is the leading cause of cancer deaths globally; 1 in 16 people are diagnosed with lung cancer in their lifetime. Microtubules, a critical cytoskeletal assembly, have an essential role in cell division. Interference with the microtubule assembly leads to genetic instability during mitosis and cancer cell death. Currently, available antimitotic drugs such as vincas and taxanes are limited due to side effects such as alopecia, myelosuppression, and drug resistance. Noscapine, an opium alkaloid, is a tubulin-binding agent and can alter the microtubule assembly, causing cancer cell death. Amino acids are fundamental building blocks for protein synthesis, making them essential for the biosynthesis of cancer cells. However, the ability of amino acids in drug transportation has yet to be exploited in developing noscapine analogues as a potential drug candidate for cancer. Hence, in the present study, we have explored the ninth position of noscapine by introducing a hydroxymethylene group using the Blanc reaction and further coupled it with a series of amino acids to construct five target conjugates in good yields. The synthesized amino acid conjugate molecules were biologically evaluated against the A549 lung cancer cell line, among which the noscapine-tryptophan conjugate showed IC50 = 32 µM, as compared to noscapine alone (IC50 = 73 µM). Morphological changes in cancer cells, cell cycle arrest in the G1 phase, and ethidium bromide/acridine orange staining indicated promising anticancer properties. Molecular docking confirmed strong binding to tubulin, with a score of -41.47 kJ/mol with all 3D coordinates and significant involvement of molecular forces, including the hydrogen bonds and hydrophobic interactions. Molecular dynamics simulations demonstrated a stable binding of noscapine-tryptophan conjugate for a prolonged time (100 ns) with the involvement of free energy through the reaction coordinates analyses, solving the bioavailability of parent noscapine to the body.