Graphene oxide-Au nano particle coated quartz crystal microbalance biosensor for the real time analysis of carcinoembryonic antigen

A label-free quartz crystal microbalance (QCM) biosensor was developed for the selective and real-time estimation of carcinoembryonic antigen (CEA) through the present study. Graphene oxide-Au nanoparticles (GO-AuNPs) was in situ synthesised on the surface of the QCM electrode and the antibody of CEA (monoclonal anti-CEA from mouse) was covalently immobilized on this layer as the bioreceptor for CEA. Mercaptoacetic acid–EDC–NHS reaction mechanism was used for anti-CEA immobilization. The effect of oxygen plasma treatment of the QCM electrode surface before bioreceptor preparation on the performance of the biosensor was tested and was found promising. CEA solutions with various concentrations were analysed using the bioreceptors to estimate the sensitivity and detection limit of the biosensor. The biosensors selectively recognized and captured CEA biomolecules with a detection limit of 0.06 and 0.09 ng mL−1 of CEA for oxygen plasma-treated (E2) and untreated (E1) bioreceptors, respectively. The sensitivity was estimated at 102 and 79 Hz, respectively, for E2 and E1. Clinical serum samples were analysed and the results were found in good agreement with the ELISA analysis. Long term stability was also found to be excellent. Langmuir adsorption isotherm was also conducted using the experimental results

Sustainability, Compostability, and Specific Microbial Activity on Agricultural Mulch Films Prepared from Poly(lactic acid)

Agricultural mulch film of poly­(lactic acid) (PLA) has been prepared under industrial conditions by the extrusion blown film method with modified properties using poly­(hydroxibutyrate) (PHB) and reactive compatibilizer maleic anhydride (MA). Processing parameters and blend composition have been optimized based upon processability and mechanical properties of the final materials. Because PLA is a biopolymer, evaluation of service life period of the mulch film is very much important. Sustainability of the film has been analyzed by keeping the films in a weatherometer, which can create accelerated weather conditions, followed by mechanical testing at regular intervals. Similarly, variation in compostability has been analyzed as per the American standard for test method, ASTM D 5988, using vermi-compost. In addition, specific microbial action on the mulch films also has been analyzed using bacteria <i>Berkholdaria cepacia</i> (<i>B. cepacia</i>), which is selective in particular toward PLA degradation and in mixed fungal inoculums

Ti3C2Tx MXene-Au nanoparticles doped polyimide thin film as a transducing bioreceptor for real-time acoustic detection of carcinoembryonic antigen

Ti3C2Tx MXene was synthesized and the 2D layers were hybridized with Au nanoparticle(AuNP) through the in-situ method. The study was successfully prepared MXene 2D layerand the same was TEM captured as well. Polyimide/MXene-AuNP (PI/Mxene-AuNP)transducing conducting nanocomposite thin film was synthesized and evaluated the newmaterial’s capability to use as a transducing thin film for biosensing application. Thebioreceptor was prepared on the delay line area of the SAW device by covalentlyimmobilizing mouse monoclonal antibody of carcinoembryonic antigen (CEA) through thethioglycolic acid arm linker mechanism. Immunoassay analysis has suggested that thebiosensor responds linearly with the increase in the concentration of the CEA sample. Thelimit of detection was observed at 0.001 ng/ml. The insertion loss of the bioreceptor wasrecorded at 10 dB, which also mattered in the high sensitivity of the biosensor. The biosensorhas shown excellent selectivity within the environment of other common tumour markers andwas stable for 75 days under periodical testing conditions. Clinical serum samples wereanalyzed successfully and the results were compared with values obtained through the ELISAmethod

Performance of Bio-Based polymeric agricultural mulch films

In order to improve yields and crop traits, polymeric films are commonly used to cover soils like agricultural mulches. Its use provides important benefits to farmers and the environment, as they maintain humidity, temperature and prevent the growth of weeds. However, the most widely used mulches are mainly made of low-density polyethylene. The use of PE films or other non-biodegradable polymers present great environmental and economic disadvantages for responsible farmers, who must remove them before the next crop period. The objective of this chapter is to discuss the main properties presented by the biodegradable and bio-based materials that have recently been proposed for this application, what is their effect on the yields of different crops in which they have been tested, as well as their biodegradation time and their effect on the soil quality will also be analyzed. Finally, based on these findings and the recently approved new standard for biodegradable agricultural mulches, the materials that will set trends in the future will be remarked.Fil: Merino, Danila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Mansilla, Andrea Yamila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; ArgentinaFil: Casalongue, Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; ArgentinaFil: Alvarez, Vera Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentin