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The increasing pollution of ecosystems by both biological and non-biological contaminants has recently fostered the rapid development of biosensors, thus opening a new investigation area in analytical sciences. Here, we review the applications of immunosensors in food safety, human health, environmental sciences, water pollution, and agriculture. We present the analysis of cancer markers, pathogens, antigens, antibiotics, pesticides, toxins, allergens, hormones, and phytohormones. Immunosensors comprise electrochemical, microgravimetric, optical, and thermometric immunosensors. Immunosensors have advantages such as enhanced sensitivity, selectivity, speed, and cost-effectiveness. In particular, antibody-based biosensors have outperformed traditional methods in identifying and analysing various compounds. Immunosensors are able to detect compounds at nanomolar to picomolar levels. [ABSTRACT FROM AUTHOR]

Peritonsillar abscess is a polymicrobial infection with acute life threatening complications if not treated promptly. Primary objective is to find the anatomical factor for unilateral abscess formation and appropriate management protocols. Secondary objectives include the bacteriological study,antibiotic preference and comparison of crypt length of both tonsils post tonsillectomy to look for any significant association. A prospective study was carried out for one year in patients with peritonsillitis or peritonsillar abscess attending the Department of ENT in our hospital. Acute cases were treated by incision and drainage followed by IV antibiotics after taking pus or throat swab for culture and sensitivity. Patients further planned for interval tonsillectomy after 6 weeks followed by histopathological examination to compare the infected side and normal side. Crypt length measurements done to see any disparity which would have lead to the development of peritonsillar abscess unilaterally. In patients with peritonsillitis or peritonsillar abscess, histopathological examination of tonsils after interval tonsillectomy showed that risk of peritonsillitis or peritonsillar abscess were more on the tonsil with larger crypt length with more preponderance on left side and in males. This study concludes that deeper the crypt length,male sex, history of recurrent tonsillitis are main risk factors for development of peritonsillar abscess. Bacteriology showed Staphylococcus aureus against the most common Streptococcus Sp. Hence prompt use of antibiotics help in early recovery and reducing complications. [ABSTRACT FROM AUTHOR]

This work investigates the photocatalytic performance of V2O5 and V3O7 nanoparticles and their nanocomposites with rGO. The as-annealed V2O5 and V3O7 nanoparticles exhibited pure orthorhombic and monoclinic structures with an optical bandgap of 2.3 and 2.5 eV, respectively. The corresponding vibrational modes using Raman and FTIR spectroscopy analysis further confirm the form. The morphological studies reveal that V2O5 and V3O7 nanoparticles possess plate and petal-like morphology, respectively. Moreover, in the case of V2O5/V3O7—rGO nanocomposites, the plate/petal-like nanoparticles are embedded within rGO sheets. Incorporating nanoparticles within rGO sheets has quenched the green photoluminescence emission, enhancing their photocatalytic performance upon irradiation with white light of 100 mW/cm2. This is ascribed to the effective transport of interfacial electrons from vanadium oxide nanoparticles to the rGO surface, reducing the recombination of photogenerated charge carriers. These results indicate that the vanadium oxide/rGO nanocomposites have potential applications in wastewater treatment. [ABSTRACT FROM AUTHOR]

When the sensor response was tested in conjunction with comorbidities of other underlying diseases, the response was highly specific to Covid-19 urinary metabolites. In recent years, research and development have focused on the early diagnosis and detection of diseases. Using molybdenum disulfide-GQD composites, a turn-on chemiluminescence sensor was developed to detect cholesterol in serum samples. [Extracted from the article]

A limited number of overexpressed transcription factors are associated with cancer progression in many types of cancer. BTB and CNC homology 1 (BACH1) is the first mammalian heme-binding transcription factor that belongs to the basic region leucine zipper (bZIP) family and a member of CNC (cap 'n' collar). It forms heterodimers with the small musculoaponeurotic fibrosarcoma (MAF) proteins and stimulates or suppresses the expression of target genes under a very low intracellular heme concentration. It possesses a significant regulatory role in heme homeostasis, oxidative stress, cell cycle, apoptosis, angiogenesis, and cancer metastasis progression. This review discusses the current knowledge about how BACH1 regulates cancer metastasis in various types of cancer and other carcinogenic associated factors such as oxidative stress, cell cycle regulation, apoptosis, and angiogenesis. Overall, from the reported studies and outcomes, it could be realized that BACH1 is a potential pharmacological target for discovering new therapeutic anticancer drugs. [ABSTRACT FROM AUTHOR]

The studies on the utilisation of supercritical fluids (SCFs) in processing chemicals and materials have garnered significant attention in the past two decades. SCFs possess both gas- and liquid-like properties that are tunable, rendering them as superior solvents for reactions and processes, for example in the delamination of graphite. SCF technologies are deemed to be potential alternatives to existing technologies for graphene production that are yet to be industrially scalable. This review features recent works on the production of graphene facilitated by SCFs, with emphasis on the conversion of graphite to graphene through exfoliation and reduction. The exfoliation processes report the yield of 6 to 27% of monolayer graphene and 3 to 25% of ≤ 5 layers of graphene, whilst the carbon-to-oxygen (C/O) ratio of graphene produced via different reduction processes ranges from 0.37 to 28.2 with interlayer spacing of 0.35 to 0.38 nm. Recent applications of gas-expanded solvents for the synthesis of graphene and the fabrication of functionalised graphene materials via SCF-aided processes are also described. In addition, a summary of the properties of common SCFs as well as the characterisation of graphene materials, such as the number of layers, C/O ratio, interlayer spacing, pore size and surface area, is included to provide insights on the process efficiency. [ABSTRACT FROM AUTHOR]

Glutathione (GSH) is a useful biomarker in the development, diagnosis and treatment of cancer. However, most of the reported GSH biosensors are expensive, time-consuming and often require complex sample treatment, which limit its biological applications. Herein, a nanobiosensor for the detection of GSH using folic acid-functionalized reduced graphene oxide-modified BSA gold nanoclusters (FA-rGO-BSA/AuNCs) based on the fluorescence quenching interactions is presented. Firstly, a facile and optimized protocol for the fabrication of BSA/AuNCs is developed. Functionalization of rGO with folic acid is performed using EDC/NHS cross-linking reagents, and their interaction after loading with BSA/AuNCs is demonstrated. The formation of FA-rGO, BSA/AuNCs and FA-rGO-BSA/AuNCs are confirmed by the state-of-art characterization techniques. Finally, a fluorescence turn-off sensing strategy is developed using the as-synthesized FA-rGO-BSA/AuNCs for the detection of GSH. The nanobiosensor revealed an excellent sensing performance for the detection of GSH with high sensitivity and desirable selectivity over other potential interfering species. The fluorescence quenching is linearly proportional to the concentration of GSH between 0 and 1.75 µM, with a limit of detection of 0.1 µM under the physiological pH conditions (pH 7.4). Such a sensitive nanobiosensor paves the way to fabricate a "turn-on" or "turn-off" fluorescent sensor for important biomarkers in cancer cells, presenting potential nanotheranostic applications in biological detection and clinical diagnosis. [ABSTRACT FROM AUTHOR]

This study optimizes the isolation parameters of cellulose nanoparticles (CNP) from kenaf fiber using central composite design (CCD). The extraction of CNP was based on three stages (i.e. 3 factors). The independent variables (factors) were NaOH dosage, amount of NaClO, and sonication time, while the dependent variables (response) were CNP size quality and degradation temperature. Later, size quality responses were fitted with a quadratic polynomial model and degradation point responses with a 2-factor interaction model (2FI). The quadratic model and 2FI models resulted R values of 0.95 and 0.79, respectively. In addition, the morphological, thermal analysis, and Fourier transform infrared (FTIR) spectroscopy indicated a progressive removal of non-cellulosic constituents. Furthermore, transmission electron microscopy (TEM) confirmed reduction in fiber diameter from ~170 μm to ~100 nm. The optimal parameters for extraction of CNP were found to be 0.2 g of NaOH/4 g of fiber at first stage, 5 ml of NaClO/4 g of fiber at the second stage, and 20 min of sonication period during the third stage. Moreover, obtained cellulose nanoparticles were thermally more stable at higher temperature. [ABSTRACT FROM AUTHOR]

The present study investigates the removal efficiency of chemical oxygen demand (COD) and total suspended solids (TSS) of anaerobically digested palm oil mill effluent in batch studies through the following 4 strategies: coagulation by chitosan, addition of ferrous sulphate (FeSO), chitosan with hydrogen peroxide (HO) and chitosan with Fenton oxidation. The parameters tested were chitosan dosage (500-12,500 mg/L), FeSO dosage (500-12,500 mg/L), mixing time (15-60 min), sedimentation time (1-4 h) and initial pH (2-9) and HO (500-7500 mg/L). Coagulation only by using chitosan (2500 mg/L) achieved the maximum COD and TSS removal of 70.22 ± 0.23 and 85.59 ± 0.13 %, respectively. An increase in the TSS removal (98.7 ± 0.06 %) but with a reduction in the COD removal (62.61 ± 2.41 %) was observed when FeSO (2500 mg/L) was added along with chitosan (2500 mg/L). Alternatively, an improvement in the COD (82.82 ± 1.71 %) and TSS (89.92 ± 0.48 %) removal efficiencies was observed when chitosan was coupled with HO (500 mg/L). Finally, chitosan (2500 mg/L) integrated with Fenton oxidation (FeSO of 2500 mg/L and HO of 500 mg/L) resulted in 100 % TSS and 73.08 ± 4.11 % COD removals. Overall chitosan with HO proved to be the most promising alternative for POME treatment compared to chitosan with Fenton oxidation. Graphical Abstract: [Figure not available: see fulltext.] Research Significance: Industrial wastewater treatment exploiting advanced oxidation processes (AOPs) involves generation of hydroxyl radicals (OH) to degrade the organic components and is a well-documented approach. In the present study, natural biomaterial chitosan as a coagulant combined with various AOP's have been investigated for the anaerobically digested palm oil mill effluent (AAD-POME) treatment. Research investigations to-date on the post-treatment of POME is very limited, and the lacking of lab-scale study could be the major reason for the failing industrial plant trials. Hence the current study explores the possibility and reports in detail on an alternative eco-friendly green processing technique for POME treatment. The objectives of present investigation focuses on the post-treatment of AAD-POME primarily by coagulation using (a) chitosan (b) chitosan with FeSO (c) chitosan with HO and (d) chitosan with Fenton oxidation. The results conclude that chitosan with HO proved to be the most promising alternative for POME treatment compared to chitosan with Fenton oxidation. [ABSTRACT FROM AUTHOR]

A double layer coating was evaluated for maintenance of quality of dragon fruit during storage at 10 ± 2 °C and 80 ± 5 % RH for 28 days. Significant differences ( p < 0.05) were observed between control and the treated fruit. However, a double layer coating with 600 nm droplet size + 1.0 % conventional chitosan showed promising results in all the tested parameters, while the fruit treated with 1,000 nm droplet size + 1.0 % conventional chitosan showed some negative effects on fruit surface. Increase in weight loss was 12.0 % in fruit treated with 600 nm droplet size and 1.0 % conventional chitosan as compared to the control. Antioxidants and gaseous analysis also proved the efficacy of double layer coatings with 600 nm droplet size + 1.0 % conventional chitosan. Thus it can be concluded from the present investigation that double layer coating could be used for maintaining quality in dragon fruit for up to 28 days without any off-flavours. [ABSTRACT FROM AUTHOR]

A novel ultrasound-assisted chitosan-surfactant nanostructure assembly was developed to allow better delivery of chitosan particles into intact fruit tissues for extension of postharvest life. Three solutions of 1 % chitosan-surfactant nanostructure assembly with micelle sizes of 400, 600 and 800 nm were prepared and applied as an edible coating on tomatoes. The fruits were stored at 15 ± 2 °C and 70-80 % relative humidity for 20 days. The indicators of tomato ripening, which included loss of firmness, decline of titratable acidity, decline of chlorophyll content and increase in soluble solid content, were delayed in the treated fruits in comparison to the control ( p < 0.05). A delay of approximately 5 days in ripening was observed by evaluating the colour evolution from green to red. The treatment significantly ( p < 0.05) enhanced the phenolic content while maintaining a lower level of respiration in comparison to the control, throughout most of the storage duration. However, weight loss was higher in the treated fruits in comparison to the control. No significant difference in the resultant effects was observed by using chitosan-surfactant nanostructure assemblies of different micelle sizes ( p > 0.05). [ABSTRACT FROM AUTHOR]