This paper unequivocally examines the production of carbon quantum dots from biomass waste, such as palm kernel shells and oyster shells, and their application in bioimaging. We also prepared carbon quantum dots from citric acid as a comparison.

Quantum dots, which won the Nobel Prize in Chemistry, have recently gained significant attention in precision medicine due to their unique properties, such as size-tunable emission, high photostability, efficient light absorption, and vibrant luminescence. Consequently, there is a growing demand to identify new types of quantum dots from various sources and explore their potential applications as stimuli-responsive biosensors, biomolecular imaging probes, and targeted drug delivery agents. Biomass-waste-derived carbon quantum dots (CQDs) are an attractive alternative to conventional QDs, which often require expensive and toxic precursors, as they offer several merits in eco-friendly synthesis, preparation from renewable sources, and cost-effective production. In this study, we evaluated three CQDs derived from biomass waste for their potential application as non-toxic bioimaging agents in various cell lines, including human dermal fibroblasts, HeLa, cardiomyocytes, induced pluripotent stem cells, and an in-vivo medaka fish (Oryzias latipes) model. Confocal microscopic studies revealed that CQDs could assist in visualizing inflammatory processes in the cells, as they were taken up more by cells treated with tumor necrosis factor-α than untreated cells. In addition, our quantitative real-time PCR gene expression analysis has revealed that citric acid-based CQDs can potentially reduce inflammatory markers such as Interleukin-6. Our studies suggest that CQDs have potential as theragnostic agents, which can simultaneously identify and modulate inflammatory markers and may lead to targeted therapy for immune system-associated diseases.

Background and Aim: Despite introducing the hepatitis B virus (HBV) vaccine, the incidence of the Hepatitis B virus globally is still a major health concern. This systematic review and meta-analysis were conducted to provide detailed information on the prevalence of HBV genotypes and subtypes in circulation in Asia. Methods: A systematic search for articles describing the prevalence of HBV genotypes and subtypes in Asia was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. Results: Our search returned 207 eligible articles involving 49,279 genotypes and 7457 subtypes representing 28 Asian countries. A meta-analysis was performed on our eligible studies using the Random effect Model. The pooled prevalence of HBV genotypes showed that genotype C (30.9%) (95% CI, 27.5–34.5%; I² = 97.57%; p < 0.001) was the most common HBV genotype in Asia, followed by genotype B (17.8%) (95% CI, 15.5–20.4%; I² = 97.26%; p < 0.001) and genotype D (15.4%) (95% CI, 11.8–19.8%). Vietnam had the highest prevalence of genotype B, Lebanon had the highest prevalence of genotypes C, and Jordan had the highest prevalence of genotype D. There was variation in genotypic prevalence with respect to the target genes for HBV genotyping. Reverse dot blot hybridization had the highest estimate of genotypes B and C. HBV subtype C2 (40.0%) (95% CI, 33.3–47.0) is the most prevalent HBV subtype. Conclusion: Evidence from this study reveals that HBV genotypes C and B are the most dominant HBV genotypes in Asia, and HBV subtype C2 is more endemic in Asia.

Quantum dots (QDs)—especially those containing cadmium—are toxic to human cells, and therefore cannot be used directly for diagnosis and treatment of human disease. To circumvent this limitation, the surface of QDs must be modified to increase their water solubility and biocompatibility. To this end, we encapsulated CdSe/ZnS QDs coupled with iron oxide nanoparticles in phospholipid micelles ranging in size from 117 to 265 nm. The QD micelles showed no cytotoxicity in A549 and HeLa cells even at higher concentrations (25 μg ml⁻¹). The ability of micelles to transport human serum albumin (HSA) protein was investigated by optical spectroscopy, and the thermodynamic parameters of the protein complexed with micelles were calculated with the van't Hoff equation at various temperatures (25–45 °C). We found that binding between micelles and HSA was stabilized by hydrogen bonds as well as electrostatic and hydrophobic forces. Fourier transform infrared spectroscopy and circular dichroism revealed changes in the secondary structure of HSA due to increment of alpha helical content, although the tertiary structure was largely preserved. The absolute quantum yield of water-soluble micelles was around 4% at an excitation wavelength 590 nm, while that of cadmium selenide (CdSe)/zinc sulfide (ZnS) QDs in chloroform was 20%. The fluorescence signal in HeLa and A549 cells remained high after 72 h of incubation with the micelles, as determined by confocal microscopy; moreover, the fluorescence signal was detected in both mother and daughter cells. These results demonstrate that CdSe/ZnS micelles are biocompatible since they do not induce cytotoxicity during long-term imaging nor affect the native structure of conjugated proteins.

From acute to chronic hepatitis, cirrhosis, and hepatocellular cancer, hepatitis B infection causes a broad spectrum of liver diseases. Molecular and serological tests have been used to diagnose hepatitis B-related illnesses. Due to technology limitations, it is challenging to identify hepatitis B infection cases at an early stage, particularly in a low- and middle-income country with constrained resources. Generally, the gold-standard methods to detect hepatitis B virus (HBV) infection requires dedicated personnel, bulky, expensive equipment and reagents, and long processing times which delay the diagnosis of HBV. Thus, lateral flow assay (LFA), which is inexpensive, straightforward, portable, and operates reliably, has dominated point-of-care diagnostics. LFA consists of four parts: a sample pad where samples are dropped; a conjugate pad where labeled tags and biomarker components are combined; a nitrocellulose membrane with test and control lines for target DNA-probe DNA hybridization or antigen-antibody interaction; and a wicking pad where waste is stored. By modifying the pre-treatment during the sample preparation process or enhancing the signal of the biomarker probes on the membrane pad, the accuracy of the LFA for qualitative and quantitative analysis can be improved. In this review, we assembled the most recent developments in LFA technologies for the progress of hepatitis B infection detection. Prospects for ongoing development in this area are also covered.

Chitosan (CTS) film was prepared by solution casting technique and characterized by means of Fourier Transform Infrared Spectroscopy (FT-IR), Thermogravimetric Analysis (TGA) and Scanning Electron Microscopy (SEM). Besides swelling index, the CTS film was investigated as a slow-release matrix for 1- and 2-naphthol (pesticide precursors) under different pH conditions. Swelling index of the CTS film was determined in different pH conditions i.e. pH 2.59, 6.84 (distilled water) and 11.02. The swelling order was found; pH 2.59 > 6.84 > 11.02. Similarly, the slow-release study was carried out at pH 2.59, 6.84 and 11.02. Over all, the release amount was found higher in acidic medium followed by neutral and basic medium. This behaviour might be due to higher swelling and dissolution of CTS film in acidic medium whereas in neutral and basic medium CTS film swells moderately.