ABSTRACT
In addition to their use as an additive to improve physical properties of solvent polymeric membranes, plasticizers have a considerable impact on the specificity and sensitivity of membrane-modified electrochemical sensors. In this work, we aim at the hybridization of two different plasticizers using the electropolymerization technique in the development of a cadmium(II)-selective electrochemical sensor based on screen-printed gold electrode along with cyclic voltammetric measurement. At this point, we first screen for the primary plasticizer yielding the highest signal using cyclic voltammetry followed by pairing it with the secondary plasticizers giving rise to the most sensitive current response. The results show that the hybridization of DOS and TOTM with 3:1 weight ratio (~137.7-µm-thick membrane) renders a signal that is >26% higher than that from the sensor plasticized by DOS per se in water. The solution of 0.1 mM hydrochloric acid (pH 4) is the optimal supporting electrolyte. In addition, hybrid plasticizers have adequate redox capacity to induce cadmium(II) transfer from bulk solution to the membrane/water interfaces. Conversion of voltammetric signals to semi-integral currents results in linearity with cadmium(II) concentration, indicating the irreversible cadmium(II) transfer to the membrane. The DOS:TOTM hybrid sensor also exhibits high sensitivity, with a limit of detection (LOD) and limit of quantitation (LOQ) of 95 ppb and 288 ppb, respectively, as well as greater specificity towards cadmium(II) than that obtained from the single plasticizer sensor. Furthermore, recovery rates of spiked cadmium(II) in water samples were higher than 97% using the hybrid plasticizer sensor. Unprecedentedly, our work reports that the hybridization of plasticizers serves as ion-to-electron transducer that can improve the sensor performance in cadmium(II) detection.
Subject(s)
Cadmium , Plasticizers , Cadmium/chemistry , Electrodes , Gold , WaterABSTRACT
The sudden outburst of Coronavirus disease 19 or COVID-19 has raised serious awareness about viral contamination on the environment, which is one of the major causes of the disease. Transmission via contaminated surfaces has been recognized as a significant route for spreading the virus. To suppress and control the spread of SARS-CoV-2, potent virucidal finishing agents for decontamination of medical textiles are urgently required. In this study, an environmental-friendly, economical, non-toxic, and practical finishing on medical textiles with potent virucidal activity was proposed with the combined concepts of a new green synthesis of TiO2@Ag core-shell nanostructures using ascorbic acid reduction and UV-curing process. In order to evaluate efficiency of virucidal activity, effects of the amount of TiO2@Ag NPs and contact time were determined against the coronavirus following ISO 18184:2019 standard. The finishing agent exhibited an excellent 99.9% virucidal efficacy. The stability of virucidal activity and mechanical properties were determined under repeated washing. The finished fabrics had the ability to retain their virucidal activity and tensile strength through 20 washes. The results suggested that the finishing agent had great potential as a potent and non-toxic virucide against the coronavirus for medical textile applications.
ABSTRACT
Streptomyces cavourensis BUU135 is a bacterial species isolated from the soil of a tropical fruit farm. The genome of S. cavourensis BUU135 comprises a gene encoding nebramycin 5' synthase, which produces nebramycin 5' by catalyzing the O-carbamoylation reaction of tobramycin. The newly sequenced 7.66-Mb draft genome of S. cavourensis BUU135 may contribute to the discovery of novel natural products derived from this organism.
ABSTRACT
Laceyella tengchongensis BKK01 is a thermophilic bacterium isolated from municipal solid waste. The genome of L. tengchongensis BKK01 includes a gene putatively encoding gramicidin S synthase. Gramicidin S has antibiotic activity against some bacteria and fungi. The newly sequenced 3.44-Mb draft genome of L. tengchongensis BKK01 will shed some light on the biosynthesis of gramicidin S.
ABSTRACT
Haloferax volcanii SS0101 is a halophilic archaeon isolated from salt farms in Thailand. The genome sequence of H. volcanii SS0101 contains a gene encoding capreomycidine synthase, a key enzyme for capreomycidine biosynthesis. This 3.8-Mb draft genome sequence of H. volcanii SS0101 will provide the tools for investigating genes involved in capeomycidine production in haloarchaea.
ABSTRACT
Polyhydroxyalkanoate (PHA) synthase is a key enzyme for PHA production in microorganisms. The class IV PHA synthase is composed of two subunits: PhaC and PhaR. The PhaR subunit, which encodes the phaR gene, is only present in class IV PHA synthases. Therefore, the phaR gene is used as a biomarker for bacteria that contain a class IV PHA synthase, such as some Bacillus spp. The phaR gene was developed to screen phaR-containing Bacillus spp. The phaR screening method involved two steps: phaR gene amplification by PCR and phaR amplicon detection using a DNA lateral flow assay. The screening method has a high specificity for phaR-containing Bacillus spp. The lowest amount of genomic DNA of B. thuringiensis ATCC 10792 that the phaR screening method could detect was 10 pg. This novel screening method improves the specificity and sensitivity of phaR gene screening and reduces the time and cost of the screening process, which could enhance the opportunity to discover good candidate PHA producers. Nevertheless, the screening method can certainly be used as a tool to screen phaR-containing Bacillus spp. from environmental samples.
ABSTRACT
Proteus mirabilis CKTH01 is a pathogenic bacterium isolated from raw chicken meat. The genome sequence of P. mirabilis CKTH01 contains genes encoding multidrug efflux pumps, which are the virulence factors of the antibiotic-resistant bacterium. This 3.98-Mb draft genome sequence of P. mirabilis CKTH01 will contribute to the understanding of the distribution of multidrug-resistant P. mirabilis in raw chicken meat at the open markets.
ABSTRACT
BACKGROUND: Pseudomonas aeruginosa is considered as one of the most emerging threats in this century. Serious infections caused by this pathogen are often treated by carbapenems which are the last resource of antibiotics. Metallo-beta-lactamases (MBLs) production is one of the most important carbepenem resistance mechanisms and is usually related with nosocomial infections caused by P. aeruginosa. This study was aimed to determine the prevalence of MBL genes and distribution pattern of MBLs producing P. aeruginosa strains in Thailand. MATERIALS AND METHODS: Specific primers were designed to detect MBL genes including IMP-, VIM-, and NDM-type MBL genes. Multilocus sequence typing method was used to determine the dissemination pattern of carbapenem-resistance among multidrug-resistant (CR-MDR) P. aeruginosa. RESULTS: A total of 153 P. aeruginosa clinical isolates were characterized as CR-MDR. Among those, 31 P. aeruginosa clinical isolates (20.3%) presented metallo-beta-lactamase genes which could be divided into VIM-type (14 strains) and IMP-type (17 strains). blaIMP-1, blaIMP-13, blaIMP-14a, and blaVIM-2 genes were detected. Moreover, a novel IMP-type MBL, blaIMP-65 was discovered and it was demonstrated to be the unique group of MBLs in Thailand. It was of interest that ST235 was the major ST type in Thailand followed by ST964 and ST111 and ST235 was detected in both MBL harboring and non-MBL harboring strains. CONCLUSION: This study reported the dissemination of MBL gene including novel MBL, blaIMP-65. This study was also demonstrated major ST of P. aeruginosa which was ST235, followed by ST964 and ST111. Moreover, it is also the first report on many P. aeruginosa STs in Thailand: ST273, ST292, ST621, ST1584, and ST1816 which emphasized the dissemination trait difference of MBLs harboring P. aeruginosa in Thailand.
ABSTRACT
Aeribacillus pallidus TD1 is a thermophilic bacterium isolated from a hot spring in Thailand. The genome sequence of A. pallidus TD1 contains a gene-encoded naphthalene dioxygenase, which is a key enzyme for naphthalene degradation. This 3.7-Mb draft genome sequence of A. pallidus TD1 will contribute to the understanding of polycyclic aromatic hydrocarbon (PAH) degradation in high-temperature environments.
ABSTRACT
Bacillus salarius IM0101 is a halophilic bacterium that was isolated from soil in Inner Mongolia, China. The genome sequence of B. salarius IM0101 contains a biomarker gene for polyhydroxyalkanoate (PHA) synthesis. This 6.9-Mb draft genome sequence of B. salarius IM0101 will provide new insights into the organism's PHA production machinery.
