Combination of Cold Atmospheric Plasma and Vitamin C Effectively Disrupts Bacterial Biofilms

Cold atmospheric plasma (CAP) is increasingly used in medical applications for eradication of bacterial and tumorcells. CAP treatment devices, known as plasma jet pens, produce reactive oxygen and nitrogen species atatmospheric pressure and room temperature. The produced reactive species are concentrated in a small andprecisely defined area, allowing for high precision medical treatments. CAP has been demonstrated as very effectiveagainst planktonic bacterial cells. Unfortunately, bacterial cells in biofilms are typically aggregated and protected bydense exopolymeric matrix, synthesized and secreted by the bacterial community. The main limitation in using CAPagainst bacterial biofilms is the thick protective matrix of extracellular polymers that shields bacterial cells within thiscomplex architecture. CAP has also been shown to effectively eradicate tumor cells, but the main current limitation isthe susceptibility of the surrounding healthy tissues to higher doses. We have recently demonstrated that vitamin C,a natural food supplement, can be used to destabilize bacterial biofilms and render them more susceptible to theCAP killing treatment. Here we discuss the possible impact that a pre-treatment with vitamin C could have on CAPapplications in medicine. Specifically, we argue that vitamin C could enhance the effectiveness of CAP treatmentsagainst both the bacterial biofilms and some selected tumors

Graphene based nanosensor for aqueous phase detection of nitroaromatics

A graphene-based nanosensor was fabricated to selectively detect nitrotriazolone (NTO) molecules with a molecularly imprinted film via simple electrical measurements. Molecularly imprinted polymer comprising chitosan was used as sensitive layer. Gold electrodes for electrical measurements were lithographically fabricated on Si/SiO2 substrate, followed by monolayer graphene transfer and polymeric film coating. Monolayer graphene and molecularly imprinted polymer were characterized by ATR-FTIR, UV-Vis, SEM and Raman spectroscopy. Transfer-length measurements (TLM) indicate that the sensor selectively and linearly responds against aqueous NTO solutions within a wide range of concentration of 0.01-0.1 mg mL(-1) that covers the lowest toxic level of NTO determined by USEPA. This nanosensor with embedded electrodes is re-usable and suitable for field applications, offering real-time electrical measurements unlike current techniques where complex analytics are required

Evolutionary Analysis of the Bacillus subtilis Genome Reveals New Genes Involved in Sporulation

Bacilli can form dormant, highly resistant, and metabolically inactive spores to cope with extreme environmental challenges. In this study, we examined the evolutionary age of Bacillus subtilis sporulation genes using the approach known as genomic phylostratigraphy. We found that B. subtilis sporulation genes cluster in several groups that emerged at distant evolutionary time-points, suggesting that the sporulation process underwent several stages of expansion. Next, we asked whether such evolutionary stratification of the genome could be used to predict involvement in sporulation of presently uncharacterized genes (y-genes). We individually inactivated a representative sample of uncharacterized genes that arose during the same evolutionary periods as the known sporulation genes and tested the resulting strains for sporulation phenotypes. Sporulation was significantly affected in 16 out of 37 (43%) tested strains. In addition to expanding the knowledge base on B. subtilis sporulation, our findings suggest that evolutionary age could be used to help with genome mining

Graphene-based biosensors for the detection of prostate cancer protein biomarkers: a review

Prostate cancer (PC) is the sixth most common cancer type in the world, which causes approximately 10% of total cancer fatalities. The detection of protein biomarkers in body fluids is the key topic for the diagnosis and prognosis of PC. Highly sensitive screening of PC is the most effective approach for reducing mortality. Thus, there are a growing number of literature that recognizes the importance of new technologies for early diagnosis of PC. Graphene is playing an important role in the biosensor field with remarkable physical, optical, electrochemical and magnetic properties. Many recent studies demonstrated the potential of graphene materials for sensitive detection of protein biomarkers. In this review, the graphene-based biosensors toward PC analysis are mainly discussed in two groups: Firstly, novel biosensor interfaces were constructed through the modification of graphene materials onto sensor surfaces. Secondly, ingenious signal amplification strategies were developed using graphene materials as catalysts or carriers. Graphene-based biosensors have exhibited remarkable performance with high sensitivities, wide detection ranges, and long-term stabilities