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Single-walled carbon nanotubes (SWNTs) have shown interesting bolometric properties, making them good candidates for the detection of infrared and terahertz radiation. However, little has been reported on the bolometric characteristics of SWNT as a function of their chirality or the possible influence of composite morphology on these properties. The separation of SWNTs based on chirality allows for almost purely semiconductive or metallic SWNTs to be studied. The current study focuses on the bolometric performance of self-assembled composite films of SWNTs. The dependence of these properties on the chirality of the SWNTs was evaluated. To this end, metallic, semiconducting, and a 1:1 mixture of metallic and semiconductive were studied. Also, a theoretical model based on the Wiedemann−Franz law is used to explain the resistance of the SWNT composite films as a function of temperature. Results show that the composite morphology has a significant impact on bolometer performance, with cracked composite films containing highly aligned SWNT arrays suspended over a silicon substrate showing superior responsivity values due to higher thermal isolation. Uncracked composite films showed superior thermal coefficient of resistance values (α = −6.5%/K), however, the responsivity was lower due to lower thermal isolation.

The demand for metallic nanoparticles synthesized using green methods has increased due to their various therapeutic and clinical applications, and plant biotechnology may be a potential resource facilitating sustainable methods of AgNPs synthesis. In this study, we evaluate the capacity of extracts from Randia aculeata cell suspension culture (CSC) in the synthesis of AgNPs at different pH values, and their activity against pathogenic bacteria and cancer cells was evaluated. Using aqueous CSC extracts, AgNPs were synthesized with 10% (w/v) of fresh biomass and AgNO3 (1 mM) at a ratio of 1:1 for 24 h of incubation and constant agitation. UV-vis analysis showed a high concentration of AgNPs as the pH increased, and TEM analysis showed polydisperse nanoparticles with sizes from 10 to 90 nm. Moreover, CSC extracts produce reducing agents such as phenolic compounds (162.2 ± 27.9 mg gallic acid equivalent/100 g biomass) and flavonoids (122.07 ± 8.2 mg quercetin equivalent/100 g biomass). Notably, AgNPs had strong activity against E. coli, S. pyogenes, P. aeruginosa, S. aureus, and S. typhimurium, mainly with AgNPs at pH 6 (MIC: 1.6 to 3.9 µg/mL). AgNPs at pH 6 and 10 had a high antiproliferative effect on cancer cells (IC50 < 5.7 µg/mL). Therefore, the use of cell suspension cultures may be a sustainable option for the green synthesis of AgNPs.