Methyl methacrylate-modified polystyrene microspheres: an effective strategy to enhance the fluorescence of Eu-complexes.

The in vitro detection applications of europium complex-doped microspheres mainly rely on strong fluorescence intensity and a well-defined morphology. In this work, using methyl methacrylate-modified polystyrene microspheres has been proven an effective strategy to enhance the fluorescence and morphology of Eu-complexes. The experimental results showed that the modification resulted in the formation of a porous structure within the polystyrene microspheres, enhancing the doping uniformity and facilitating a more significant accumulation of fluorescent molecules. Furthermore, because of their encapsulation ability, microspheres efficiently confine the fluorescent molecules within them. In addition, the nano-scale porous structure endowed the microspheres with enhanced properties without compromising solvent swelling capability, thereby significantly boosting the fluorescence performance of porous PSMMA. In lateral flow immunoassays (LFIAs), PSMMA-Eu microspheres were effectively utilized to detect fentanyl with exceptional sensitivity by capitalizing on these benefits, capable of detecting concentrations as low as 0.10 ng mL-1. This technology has significant potential for rapid point-of-care screening and clinical applications.

Temporally and spatially resolved molecular profiling in fingerprint analysis using indium vanadate nanosheets-assisted laser desorption ionization mass spectrometry.

This study presents the first-ever synthesis of samarium-doped indium vanadate nanosheets (IVONSs:Sm) via microemulsion-mediated solvothermal method. The nanosheets were subsequently utilized as a nano-matrix in laser desorption/ionization mass spectrometry (LDI-MS). It was discovered that the as-synthesized IVONSs:Sm possessed the following advantages: improved mass spectrometry signal, minimal matrix-related background, and exceptional stability in negative-ion mode. These qualities overcame the limitations of conventional matrices and enabled the sensitive detection of small biomolecules such as fatty acids. The negative-ion LDI mechanism of IVONSs:Sm was examined through the implementation of density functional theory simulation. Using IVONSs:Sm-assisted LDI-MS, fingerprint recognitions based on morphology and chemical profiles of endogenous/exogenous compounds were also achieved. Notably, crucial characteristics such as the age of an individual's fingerprints and their physical state could be assessed through the longitudinal monitoring of particular biomolecules (e.g., ascorbic acid, fatty acid) or the specific biomarker bilirubin glucuronide. Critical information pertinent to the identification of an individual would thus be facilitated by the analysis of the compounds underlying the fingerprint patterns.

Facile synthesis of noncytotoxic PEGylated dendrimer encapsulated silver sulfide quantum dots for NIR-II biological imaging.

Near-infrared-II (NIR-II, 1000-1700 nm) bioimaging features high penetration depth and high spatio-temporal resolution compared to traditional fluorescence imaging, but the key is to develop stable and biocompatible NIR-II fluorophores suitable for in vivo applications. Silver sulfide quantum dots (Ag2S QDs) have been demonstrated to be excellent for in vivo NIR-II imaging with unique optical properties and decent biocompatibility, but they often require complex post modifications for in vivo applications. Herein we demonstrate a facile one-pot strategy to synthesize PEGylated dendrimer-encapsulated Ag2S QDs useful for in vivo NIR-II imaging. Silver ions were first loaded into the core of an acylthiourea-functionalized dendrimer (PEG-PATU) through coordination between silver ions and acylthiourea groups, followed by the addition of sodium sulfide to form Ag2S QDs in situ. The resulting PEG-PATU Ag2S QDs exhibit excellent NIR-II fluorescence signals, and thus could be used for high efficiency labelling and tracking of A549 cancer cell mobility in vivo and real time visualization of the vast circulatory network of a mouse.

Reproducibility of "The Bethesda System for Reporting Thyroid Cytopathology:" A Retrospective Analysis of 107 Patients.

OBJECTIVES: Fine-needle aspiration cytology (FNAC) has emerged as an indispensable tool to discriminate thyroid lesions into benign or malignant for appropriate management. The need for simplicity of communication and standardization of terminology for thyroid FNAC reporting led to introduction of "The Bethesda system for reporting Thyroid Cytopathology" (TBSRTC) in a conference held at the National Cancer Institute in 2007. This study aims at establishing the reproducibility of TBSRTC for diagnosing thyroid lesions. MATERIALS AND METHODS: The present study comprised thyroid FNAC from 107 patients retrospectively over a period of 1.5 year (June 2013 to December 2014), which were reviewed by two trained cytopathologists and re-categorized according to TBSRTC. The interobserver variation and reproducibility of the reporting system was statistically assessed using Cohen's kappa. RESULTS: The cytopathologists were in agreement in 98 out of 107 cases (91.5%). Maximum concordance was noted in benign category (91 of 96 cases; 92.85%), followed by 2 cases each in nondiagnostic/unsatisfactory (ND/US) and follicular neoplasm/suspicious for follicular neoplasm (FN/SFN) category (2.04% each) and 1 case each in atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS), suspicious for malignancy (SUS), and malignant category (1.02% each). The highest diagnostic disagreement was noted among ND/US and benign and benign and FN/SFN categories. CONCLUSION: The utilization of TBSRTC for reporting thyroid cytology should be promoted in our country because it provides a homogeneous, standardized, and unanimous terminology for cytological diagnosis of thyroid lesions. The present study could substantiate the diagnostic reproducibility of this system.