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Carbon-based nanomaterials are key to developing high-performing electrochemical sensors with improved sensitivity and selectivity. Nonetheless, limitations in their fabrication and integration into devices often constrain their practical applications. Moreover, carbon nanomaterials-based electrochemical devices still face problems such as large background currents, poor stability, and slow kinetics. To advance towards a new class of carbon nanostructured electrochemical transducers, we propose the in-situ polymerization and carbonization of furfuryl alcohol (FA) on porous silicon (pSi) to produce a tailored and highly stable transducer. The thin layer of polyfurfuryl alcohol (PFA) that conformally coats the pSi scaffold transforms into nanoporous carbon when subjected to pyrolysis above 600 °C. The morphological and chemical properties of PFA-pSi were characterized by scanning electron microscopy, and Raman and X-ray photoelectron spectroscopies. Their stability and electrochemical performance were investigated by cyclic voltammetry and electrochemical impedance spectroscopy in [Fe(CN)6]3-/4-, [Ru(NH3)6]2+/3+, and hydroquinone. PFA-pSi showed superior electrochemical performance compared to screen-printed carbon electrodes while also surpassing glassy carbon electrodes in specific aspects. Besides, PFA-pSi has the additional advantage of easy tuning of the electroactive surface area. To prove its potential for biosensing purposes, a DNA sensor based on quantifying the partial pore blockage of the pSi upon target hybridization was built on PFA-pSi. The sensor showed a limit of detection of 1.4 pM, outperforming other sensors based on the same sensing mechanism.

Omega-3 fatty acids and probiotic bacteria were co-encapsulated in a single whey protein isolate (WPI)–gum Arabic (GA) complex coacervate microcapsule. Tuna oil (O) and Lactobacillus casei 431 (P) were used as models of omega-3 and probiotic bacteria, respectively. The co-microcapsules (WPI-P-O-GA) and L. casei containing microcapsules (WPI-P-GA) were converted into powder by using spray and freeze drying. The viability of L. casei was significantly higher in WPI-P-O-GA co-microcapsules than in WPI-P-GA. The oxidative stability of tuna oil was significantly higher in spray dried co-capsules than in freeze dried ones.