Sample Preparation and Diagnostic Methods for a Variety of Settings: A Comprehensive Review

Portable smartphone platform utilizing AIE-featured carbon dots for multivariate visual detection for Cu2+, Hg2+ and BSA in real samples

Heavy metals cause serious toxic threats to both environment and human health. The multivariate, instrument-free, portable, and rapid detection strategy is crucial for determination of heavy metals. Herein, aggregation-induced emission (AIE) featured carbon dots (SN-CDs) were fabricated hydrothermally by optimizing co-doping precursors. With bright yellow emission at 560 nm, the SN-CDs were utilized for multivariate sensing Cu2+, Hg2+ and bovine serum albumin (BSA) based on AIE behavior and static quenching effect, with detection limits of 0.46 μmol·L-1, 25.8 nmol·L-1 and 1.52 μmol·L-1. A portable smartphone platform was constructed to enable portable, prompt, and sensitive analysis for Cu2+, Hg2+, and BSA via different strategies in real water and food samples with satisfied recovery. Moreover, a logic gate circuit was designed to provide the possibilities for utilization of intelligent facility. The proposed AIE SN-CDs possessing great contribution in preferable sensing performance, present promising prospects in real-time monitoring of environment and food safety.

Miniature mass spectrometer-based point-of-care assay for quantification of metformin and sitagliptin in human blood and urine

Metformin (MET) and sitagliptin (STG) are widely used as the first-line and long-term oral hypoglycemic agents for managing type 2 diabetes mellitus (T2DM). However, the current lack of convenient and rapid measurement methods poses a challenge for individualized management. This study developed a point-of-care (POC) assay method utilizing a miniature mass spectrometer, enabling rapid and accurate quantification of MET and STG concentrations in human blood and urine. By combining the miniature mass spectrometer with paper spray ionization, this method simplifies the process into three to four steps, requires minimal amounts of bodily fluids (50 μL of blood and 2 μL of urine), and is able to obtain quantification results within approximately 2 min. Stable isotope-labeled internal standards were employed to enhance the accuracy and stability of measurement. The MS/MS responses exhibited good linear relationship with concentration, with relative standard deviations (RSDs) below 25%. It has the potential to provide immediate treatment feedback and decision support for patients and healthcare professionals in clinical practice.

Laboratory tools for the direct detection of bacterial respiratory infections and antimicrobial resistance: a scoping review

Rapid laboratory tests are urgently required to inform antimicrobial use in food animals. Our objective was to synthesize knowledge on the direct application of long-read metagenomic sequencing to respiratory samples to detect bacterial pathogens and antimicrobial resistance genes (ARGs) compared to PCR, loop-mediated isothermal amplification, and recombinase polymerase amplification. Our scoping review protocol followed the Joanna Briggs Institute and PRISMA Scoping Review reporting guidelines. Included studies reported on the direct application of these methods to respiratory samples from animals or humans to detect bacterial pathogens ±ARGs and included turnaround time (TAT) and analytical sensitivity. We excluded studies not reporting these or that were focused exclusively on bioinformatics. We identified 5,636 unique articles from 5 databases. Two-reviewer screening excluded 3,964, 788, and 784 articles at 3 levels, leaving 100 articles (19 animal and 81 human), of which only 7 studied long-read sequencing (only 1 in animals). Thirty-two studies investigated ARGs (only one in animals). Reported TATs ranged from minutes to 2 d; steps did not always include sample collection to results, and analytical sensitivity varied by study. Our review reveals a knowledge gap in research for the direct detection of bacterial respiratory pathogens and ARGs in animals using long-read metagenomic sequencing. There is an opportunity to harness the rapid development in this space to detect multiple pathogens and ARGs on a single sequencing run. Long-read metagenomic sequencing tools show potential to address the urgent need for research into rapid tests to support antimicrobial stewardship in food animal production.

Magnetic capture device for large volume sample analysis

Immunomagnetic separation (IMS) techniques employing superparamagnetic particles can successfully isolate various components from mixtures. However, their utility can be limited for large-volume samples, viscous samples, or those containing a high density of particulate matter because of the need to generate high field gradients for particle recovery. Therefore, a new class of immunomagnetic particles was devised utilizing a single, macroscopic Pyrex spinbar conjugated with biorecognition elements to address these limitations. Advantages include an inherent capacity for effective mixing, an almost instantaneous recovery of the spinbar that can be performed without expensive equipment and with no loss of magnetic particles during processing, and reduced transfer of sample matrix. As a result, spinbars can provide an effective means for IMS with large-volume assays composed of complex matrices.

Biomarkers in psychiatric disorders

Psychiatric disorders represent a significant socioeconomic and healthcare burden worldwide. Of these, schizophrenia, bipolar disorder, major depressive disorder and anxiety are among the most prevalent. Unfortunately, diagnosis remains problematic and largely complicated by the lack of disease specific biomarkers. Accordingly, much research has focused on elucidating these conditions to more fully understand underlying pathophysiology and potentially identify biomarkers, especially those of early stage disease. In this chapter, we review current status of this endeavor as well as the potential development of novel biomarkers for clinical applications and future research study.

Smartphone-Based High-Throughput Fluorimetric Assay for Histidine Quantification in Human Urine Using 96-Well Plates

A high-throughput fluorimetric assay for histidine was developed, using a 96-well plates platform. The analyte reacts selectively with o-phthalaldehyde under mild alkaline conditions to form a stable derivative. Instrumental-free detection was carried out using a smartphone after illumination under UV light (365 nm). The method was proved to be linear up to 100 μM histidine, with an LLOQ (lower limit of quantification) of 10 μM. The assay was only prone to interference from glutathione and histamine that exist in the urine samples at levels that are orders of magnitude lower compared to histidine. Human urine samples were analyzed following minimum treatment and were found to contain histidine in the range of 280 to 1540 μM. The results were in good agreement with an HPLC corroborative method.

Prototype for rapid test devices to detect residues of sulfonamides in chicken carcasses from traditional breeders in Surabaya, Indonesia

Background and Aim

Sulfadiazine, one of the sulfonamide group's active compounds, is widely used for therapeutic production against several diseases. Veterinary drug residues can have a significant impact on human health conditions. This study aimed to develop a prototype of rapid test devices (RTDs) for detecting sulfadiazine residues on chicken carcasses based on the color indication.

Materials and Methods

Seven samples of carcasses collected from traditional breeders in Surabaya-Indonesia were prepared and tested using RTDs. This sample represents the population considering that in the last report, the use of antibiotics was more than 40%, while the ability to monitor RTDs was estimated at 100. The standard color of purple by Hex code standard color or decimal code color was used to compare the positive samples. A light-emitting diode (LED) lamp was used to observe purple color. Analysis of sulfonamides resulting from RTDs was compared using a ultraviolet-visible spectrophotometer.

Results

Sulfonamides contamination levels of 50% and 100% were detected at concentrations of 0.472 μg/mL and 0.642 μg/mL, respectively. Sulfonamides contamination that was <0.395 μg/mL did not appear purple.

Conclusion

The study's findings showed that RTDs can be used to detect sulfonamides residues at a limit of detection 0.5 mg/mL after a 45 min exposure to an LED operating at a wavelength of 980 nm (p < 0.05). The limitation of RTDs was not being able to monitor the presence of residues bound in fat samples. Rapid test devices can be developed for commonly monitoring devices due to the limited technology available in the market.