Current Analytical Chemistry - Volume 19, Issue 9, 2023

Cancer remains a formidable global health challenge, underscoring the critical need for early and accurate diagnostic tools. In recent years, nanotechnology has emerged as a promising frontier in cancer detection, offering innovative approaches to enhance sensitivity, specificity, and convenience in diagnostics. This comprehensive review delves into the intersection of nanotechnology and sputum-based assays for cancer detection. Sputum, a readily accessible biomarker source, has gained increasing attention due to its potential to house early cancer biomarkers. By harnessing the unique properties of nanoparticles, this review explores how nanotechnology is revolutionizing sputum- based cancer detection. We examine the intrinsic attributes of sputum as a diagnostic fluid, the diverse applications of nanoparticles, and the evolving landscape of cancer-specific biomarkers. Moreover, we provide insights into various nanotechnology assay techniques and their clinical implications while highlighting the challenges and future prospects in this dynamic field. This review aims to elucidate the transformative impact of nanotechnology on cancer diagnostics through sputum, offering a roadmap towards earlier and more accurate cancer detection.

Background: The infection caused by the dengue fever virus is a severe threat to public health on a global scale; nevertheless, there is currently no effective medical treatment or vaccine available to prevent or treat the condition. Objective: To better understand the physicochemical regularities of these proteins, it is necessary to carry out a computational multiparametric study of the amino acid sequences of envelope proteins expressed by the dengue fever virus and obtain a bioinformatics method that can use the subsequences of the training protein group to figure out the preponderant function of a protein, up to its sequence. Methods: Essentially, at the amino acid level, various computational programs were applied to the sequences expressing the dengue virus envelope glycoproteins to determine the PIM 2.0 v profile and the Protein Intrinsic Disorder Predisposition (PIDP) profile of each protein, and then, at the nucleotide level, a set of programs for genomic analysis was applied. Finally, these results were contrasted with statistical tests. Results: The re-creation of structural morphological similarities provided by specific regularities in the PIM 2.0 v profile and PIDP of the proteins from diverse dengue fever virus envelopes made it possible to propose a computer method that employs the PIM 2.0 v profile to identify this group of proteins based on their sequences; based on our findings, this method is a "fingerprint" of this protein group. Conclusion: The typical PIM 2.0 v profiles of the dengue fever virus proteins might be reproduced by computational tools. This knowledge will be helpful in gaining a better understanding of the newly discovered virus. Moreover, the method introduced here can identify, from the sequence, the predominant function of the protein.

Background: Silymarin (SM) is a mixture of seven flavonolignans (FL) and one flavonoid extracted from the seeds of the milk thistle plant. The major FLs include silibinin, silychristin, silydianin, and isosilibinin. Silibinin, a mixture of two diastereomers, i.e., silybin A and silybin B, has been found to be the most active biomarker molecule in the extract of SM. Some studies have also demonstrated the usefulness of other biomarkers. However, most studies have characterized SM extract with respect to silibinin only. In our previous study, we isolated five different biomarkers (silychristin, silibinin, and isosilibinin (mixture of isosilybin A and B)) and denoted them as SM phytopharmaceuticals (PP). In other research, we have combined the SM PP with two bioavailability enhancers, i.e., Piperine (PIP) and fulvic acid (FA). The formulation containing 140 mg SM PP, 10% PIP and 20% FA was optimized using dissolution testing, and its enhanced permeability was demonstrated by ex-vivo gut sac study and Confocal laser scanning microscopy (CLSM). Methods: In this research, we have compared the bioavailability of SM suspension with SM PP and the optimized formulation in C57BL/6J mice. Furthermore, the bioavailability estimation was done for three biomarkers simultaneously, i.e., silychristin, silibinin, and isosilibinin. Results: Comparing the results for three different groups, it was found that the order of Cmax was F1> SM PP> SM suspension for all three biomarkers. For all the three biomarkers, the value of Cmax was at least two times more for F1 as compared to SM suspension. However, the Tmax remained constant i.e., 2 h for all the three groups and for all the three biomarkers. Furthermore, the clearance values were found to be in the order SM suspension > SM PP > F1. Conclusion: The PIP and FA present in this combination increased the clearance value and Cmax, respectively, of the formulation. Hence, this combination of SM PP with PIP and FA has shown a better pharmacokinetic profile than SM suspension, thus, it can serve as a better alternative for the treatment of liver disease.

Background: Saxitoxin (STX) stands as one of the most potent marine biotoxins, exhibiting high lethality. Despite its severity, current treatments remain ineffective, and existing detection techniques are limited due to ethical concerns and technical constraints. Methods: Herein, an innovative approach was constructed for STX detection, utilizing mesoporous silica nanoparticles (MSN) as a foundation. This innovative, easy, and label-free aptamer (Apt)- sensor was fabricated. Apts were employed as molecular identification probes and "gated molecules," while rhodamine 6G was encapsulated within particles to serve as a signal probe. In a lack of STX, Apts immobilized on an MSN surface kept a "gate" closed, preventing signal probe leakage. Upon the presence of STX, the "gate" opened, allowing a particular binding of Apts to STX and a subsequent release of a signal probe. Results: Experimental results demonstrated a positive correlation between fluorescence intensity and concentrations of STX within a range of 1 to 80 nM, with an exceptional limit of detection of 0.12 nM. Furthermore, the selectivity and stability of a biosensor were rigorously evaluated, validating its reliability. Conclusion: This newly developed sensing strategy exhibits remarkable performance in STX detection. Its success holds significant promise for advancing portable STX detection equipment, thereby addressing a pressing need for efficient and ethical detection methods in combating marine biotoxin contamination.

Background: In borax buffer, ephedrine (EPH) and pseudoephedrine (PSE) can be well separated (Rs>10) in capillary electrophoresis (CE) without adding any other compounds, but the specific mechanism remains unclear. Methods: Titration analysis, nuclear magnetic resonance analysis, mass spectrum analysis and molecular modeling were used to investigate the separation mechanism. Results: Tetrahydroxy borate (a hydrolyzate of borax or boric acid) could react with ephedrine and pseudoephedrine to form self-assembled complexes, but the two complexes had different stabilities and electrophoretic mobilities resulting from the different steric configurations of analytes. Conclusion: The complexation based on borax was responsible for the separation.