ABSTRACT
The high surface-area-to-volume ratio of colloidal quantum dots (QDs) positions them as promising materials for high-performance supercapacitor electrodes. However, the challenge lies in achieving a highly accessible surface area, while maintaining good electrical conductivity. An efficient supercapacitor demands a dense yet highly porous structure that facilitates efficient ion-surface interactions and supports fast charge mobility. Here we demonstrate the successful development of additive-free ultrahigh energy density electric double-layer capacitors based on quantum dot hierarchical nanopore (QDHN) structures. Lead sulfide QDs are assembled into QDHN structures that strike a balance between electrical conductivity and efficient ion diffusion by employing meticulous control over inter-QD distances without any additives. Using ionic liquid as the electrolyte, the high-voltage ultrathin-film microsupercapacitors achieve a remarkable combination of volumetric energy density (95.6 mWh cm-3) and power density (13.5 W cm-3). This achievement is attributed to the intrinsic capability of QDHN structures to accumulate charge carriers efficiently. These findings introduce innovative concepts for leveraging colloidal nanomaterials in the advancement of high-performance energy storage devices.
ABSTRACT
Hydroxyapatite-derived eggshell biowaste (Hap-Esb) has been fabricated and developed for the electrochemical detection of uric acid (UA). The physicochemical characteristics of the Hap-Esb and modified electrodes were evaluated using a scanning electron microscope and X-ray Diffraction analysis. Utilized as UA sensors, the electrochemical behavior of modified electrodes (Hap-Esb/ZnONPs/ACE) was assessed using cyclic voltammetry (CV). The superior peak current response observed for the oxidation of UA at Hap-Esb/ZnONPs/ACE, which was 13 times higher than that of the Hap-Esb/activated carbon electrode (Hap-Esb/ACE) is attributed to the simple immobilization of Hap-Esb on zinc oxide nanoparticle-modified ACE. The UA sensor exhibited a linear range at 0.01 to 1 µM, low detection limit (0.0086 µM), and excellent stability, which surpass the existing Hap-based electrodes reported in the literature. The facile UA sensor subsequently realized is also advantaged by its simplicity, repeatability, reproducibility, and low cost, applicable for real sample analysis (human urine sample).
ABSTRACT
The newly isolated Trametes polyzona PBURU 12 demonstrated a high tolerance and potential for the degradation of phenanthrene. The fungal isolate was able to tolerate 100 ppm of phenanthrene with 45% relative growth. The crude laccase produced by Trametes polyzona PBURU 12 was able to degrade phenanthrene by up to 98% within 24 h. The degradation metabolites showed the absence of toxic compounds. Microbial viability tests using E. coli and B. subtilis revealed that the treated phenanthrene was less toxic than untreated phenanthrene. Phytotoxicity and genotoxicity tests, using Vigna radiata and Allium cepa, indicated that the treated phenanthrene was less toxic to the plants. No mutagenic activity was found in the Ames test. The crude laccase from Trametes polyzona PBURU 12 was demonstrated as a potential tool for the biodegradation of PAHs (phenanthrene), with low toxic effects after the degradation.
ABSTRACT
INTRODUCTION: Thalassemia is a genetic disorder, which shows, varies phenotype due to genetic modifier. XmnI is one of the genetic modifiers which affect clinical severity in thalassemia. XmnI polymorphism may increase HbF production beyond fetal life, thus ameliorating the clinical phenotype. AIM: this study aimed to investigate the difference in HbF level and the relation of HbF level and XmnI polymorphism in Thalassemia Major (TM) and Thalassemia Intermedia (TI) patients. METHODS: forty-eight beta thalassemia patients (28 males and 20 females), consists of 16 TM and 32 TI; mean age, 25.30 year old. Hemoglobin Fetal and HbA2 level were determined using High performance Liquid Chromatography (HPLC), and XmnI polymorphism was confirmed by PCR-RFLP. Statistical analysis was done using T-test, Mann-Whitney and Pearson Chi-square. RESULTS: The frequency of heterozygote (+/-) XmnI polymorphism in TM and TI patients was 56.25% vs 71.87%, while the frequency of homozygote (-/-) in TM and TI was 43.75% vs 28.13% with p value >0.05. The insignificant difference also found in HbF level between XmnI +/- and -/- in TM and TI patients. CONCLUSION: This study revealed that thalassemia major and thalassemia intermedia patients in East Java showed similar XmnI polymorphism. These phenomena also showed by HbF level in relation to XmnI polymorphism in the phenotype groups (TM and TI).
