Selective visual staining of polyurethane microplastics by novel colorimetric and near-infrared (NIR) fluorescent dye: Application to environmental water and natural soil samples.

Microplastics can cause environmental pollution and ecosystem destruction as well as human health problems. Among the types of microplastics, polyurethane (PU) is particularly resistant to heat and difficult to decompose, causing disposal problems, and is evaluated as one of the most hazardous polymers. We present a novel colorimetric and near-infrared (NIR) fluorescence dye, (E)-N-(2-((4-(diphenylamino)benzylidene)amino)phenyl)- 7-nitrobenzo[c][1,2,5]oxadiazol-4-amine (DPNA), designed for selective visual PU microplastic staining. The intramolecular charge transfer (ICT) properties of DPNA are demonstrated through density functional theory (DFT) calculations along with solvatochromic shift. DPNA exhibits red color and red fluorescence emission, showing promising potential as a staining dye. To achieve selective PU microplastic staining, we establish an optimized experimental procedure with the staining dye DPNA by evaluating the staining efficiency under different staining solvent compositions and staining times. DPNA can distinguish PU by both red fluorescence signal and red coloration among different types of microplastics. In addition, DPNA well stain fresh PUs with diverse sizes and at various pH range of 5-9, and the aged PUs can also be dyed as effectively as the fresh PU. Most importantly, DPNA selectively stains PU among 11 types of microplastics and 5 types of natural particles in environmental water and soil with and without any pre-treatments. The adsorption mechanism of DPNA on PU microplastic is demonstrated through field emission scanning electron microscopes (FE-SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and non-covalent interaction (NCI)-reduced density gradient (RDG) analyses, and proposed that intermolecular hydrogen bonding has a significant effect.

Smartphone-Based Quantitative Measurement of Cu2+: Fluorescent Turn-on Chemosensor via Radical Cation Formation.

We report a unique radical cation formation-based fluorescent chemosensor (E)-N'-(4-(diphenylamino)benzylidene)thiophene-2-carbohydrazide (DBTC) that quantitatively determines Cu2+ based on the RGB model using a smartphone. DBTC exhibited a weak turquoise fluorescence due to fluorescence suppression by amide isomerization. When Cu2+ was added into DBTC, it showed strong light blue fluorescence with a high quantum yield ([Formula: see text] = 0.470). The detection limit of Cu2+ was determined to be 0.40 µM at the concentration range of 0-7.5 µM. In addition, the detection mechanism of DBTC for Cu2+ was demonstrated to be an oxidative cyclization reaction through 1H NMR titration, ESI-MS analysis, and DFT calculation. Remarkably, DBTC could be applied to the quantitative measurement of Cu2+ using a smartphone and RGB analysis. The detection limit was calculated to be 0.05 µM, which is the lowest detection limit among chemosensors that could detect Cu2+ through smartphone-based fluorescence measurements. Additionally, spike and recovery experiments conducted with different concentrations of Cu2+ showed good recovery values. DBTC exhibited its potential as a chemosensor for determining Cu2+ through the application of a smartphone-based platform capable of real-time monitoring.

A colorimetric/ratiometric chemosensor based on an aggregation-induced emission strategy for tracing hypochlorite in vitro and in vivo.

Excessive levels of hypochlorite (ClO-) negatively affect environmental and biological systems. Thus, it is essential to develop sensors that can identify ClO- in various systems such as the environment and living organisms. In this study, we report the development and evaluation of a novel aggregation-induced emission (AIE) strategy-based colorimetric and ratiometric fluorescent chemosensor 2,2'-(((1E,1'E)-[2,2'-bithiophene]- 5,5'-diylbis(methanylylidene))bis(hydrazin-1-yl-2-ylidene))bis(N,N,N-trimethyl-2-oxoethan-1-aminium) chloride (BMH-2∙Cl) for detecting ClO-. BMH-2∙Cl enabled highly selective ClO- detection through a color change from yellow to colorless and a fluorescence color change from turquoise to blue in a perfect aqueous solution. BMH-2∙Cl exhibited low limits of detection (2.4 ×10-6 M for colorimetry and 2.9 ×10-7 M for ratiometric fluorescence) for detecting ClO- with a rapid response within 5 s. The detection mechanism for ClO- and an AIE property change of BMH-2∙Cl were demonstrated by 1H NMR titration, ESI-MS, variation of water fraction (fw) and theoretical calculations. In particular, we confirmed not only the practicality of BMH-2∙Cl by using test strips, but also demonstrated the potential for efficient ClO- detection in biological and environmental systems such as real water samples, living zebrafish and bean sprouts.

Utility of sodium tetradecyl sulfate sclerotherapy from benign oral vascular lesion.

BACKGROUND: Hemangioma and vascular malformation are benign vascular lesions that often occur in cephalic and cervical region. Currently, surgical resection, laser therapy, angiographic embolization, use of steroids, and sclerotherapy are used as treatments. CASE PRESENTATION: This study reports three cases of benign vascular lesions that are remarkably treated by sodium tetradecyl sulfate (STS) injection, of which occurred in oral cavity and around the mouth. Three percent of STS was diluted with 0.9 % of normal saline, and it was injected to the lesion site at least once. The result of treatment was evaluated based on clinical findings. CONCLUSION: Surgical treatment of hemangioma and vascular malformation occurred in oral cavity is not normally used because of esthetic issues and potential hemorrhage. On the other hand, sclerotherapy using STS is an effective therapy compare to surgical treatment. Despite the number of STS injection was different for each patient, all three patients had reached satisfactory level through the treatment with gradual diminution of lesions.

Supernumerary nostril: a case report.

BACKGROUND: Supernumerary nostril is a congenital anomaly that contains additional nostril with or without accessory cartilage. These rare congenital nasal deformities result from embryological defects. Since 1906, Lindsay (Trans Pathol Soc Lond. 57:329-330, 1906) has published the first research of bilateral supernumerary nostrils, and only 34 cases have been reported so far in the English literature. CASE PRESENTATION: A 1-year-old female baby was brought to our department group for the treatment of an accessory opening above the left nostril which had been presented since her birth. Medical history was non-specific and her birth was normal. The size of a supernumerary nostril was about 0.2 cm diameter and connected to the left nostril. The right one was normal. Minimal procedure was operated for the anomaly. After 1 year, rhinoplasty was performed for the nostril asymmetry. CONCLUSIONS: At 1 year follow-up, the functional and cosmetic result was satisfactory. In this case, it is important that we have early preoperative diagnosis. Also, it is desirable that we should perform a corrective surgery as soon as possible for the patient's psychosocial growth.