A sensitive intelligent point-of-care test method for tert-butylhydroquinone in edible oil via a test strip with a smartphone.

Tert-butylhydroquinone (TBHQ) is easily overused or illegally added to edible oil and attracts a growing concern because of its cytotoxic, liver-damaging, and carcinogenic effects. Thus, a sensitive and intelligent point-of-care testing (iPOCT) method is developed to fulfill the on-site monitoring. This iPOCT method depended on a fluorescent immunochromatographic assay within 15 min. Under optimization, the limit of quantification (LOQ) was calculated as 0.03 µg mL-1. The iPOCT method provided a low limit of detection (LOD) of 0.02 µg mL-1, a wide linear range of 0.03-100 µg mL-1, and great selectivity. Recoveries by the spiking experiments ranged from 97.4% to 103.5% with relative standard deviations (RSDs) of 2.4%-4.9% in soybean, peanut, rapeseed, and corn oil samples. The results showed that the iPOCT method is highly consistent with the high-performance liquid chromatography (HPLC) method.

Simultaneous detection of two subtypes of extracellular vesicles using ultrabright fluorescent nanosphere-based test strips.

In recent years, the cargo profiles of extracellular vesicles (EVs), which were inherited from their parent cells, have emerged as a reliable biomarker for liquid biopsy (LB) in disease diagnosis, prognosis, and treatment monitoring. EVs secreted by different cells exhibit distinct characteristics, particularly in terms of disease diagnosis and prediction. However, currently available techniques for the quantitative analysis of EV cargoes, including enzyme-linked immunosorbent assay (ELISA), cannot specifically identify the cellular origin of EVs, thus seriously affecting the accuracy of EV-based liquid biopsy. In light of this, we here developed ultrabright fluorescent nanosphere (FNs)-based test strips which have the unique capability to specifically assess the levels of PD-L1-positive EVs (PD-L1+ EVs) derived from both tumor cells and immune cells in bodily fluids. The levels of PD-L1+ EV subpopulations in human saliva were quantified using the ultrabright fluorescent nanosphere-based test strips with more convenience and higher efficiency (detection time <30 min). Results demonstrated that the fluorescence intensity of the test line exhibited a good linear relationship respectively with the PD-L1 levels of tumor cell- (R2 = 0.993) and immune cell-derived EVs (R2 = 0.982) in human saliva. By assessing the levels of PD-L1+ EV subpopulations, our test strips hold immense potential for advancing the application of PD-L1+ EV subpopulation-based predictions in tumor diagnosis and prognosis evaluation. In summary, by integrating the benefits of FNs and lateral flow chromatography, we here provide a strategy to accurately measure the cargo levels of EVs originating from diverse cell sources in bodily fluids.

Discrepancy of Growth Toxicity of Polystyrene Nanoplastics on Soybean (Glycine max) and Mung Bean (Vigna radiata).

Nanoplastics, as a hot topic of novel contaminants, lack extensive concern in higher plants; especially the potential impact and mechanism of nanoplastics on legume crops remains elusive. In this study, the toxicity of polystyrene nanoplastics (PS-NPs, 200 nm) with diverse doses (control, 10, 50, 100, 200, 500 mg/L) to soybean and mung bean plants grown hydroponically for 7 d was investigated at both the macroscopic and molecular levels. The results demonstrated that the root length of both plants was markedly suppressed to varying degrees. Similarly, mineral elements (Fe, Zn) were notably decreased in soybean roots, consistent with Cu alteration in mung bean. Moreover, PS-NPs considerably elevated malondialdehyde (MDA) levels only in soybean roots. Enzyme activity data indicated mung bean exhibited significant damage only at higher doses of PS-NPs stress than soybean, implying mung bean is more resilient. Transcriptome analysis showed that PS-NPs stimulated the expression of genes associated with the antioxidant system in plant roots. Furthermore, starch and sucrose metabolism might play a key role in coping with PS-NPs to enhance soybean resistance, but the MAPK pathway was enriched in mung bean. Our findings provide valuable perspectives for an in-depth understanding of the performance of plants growing in waters contaminated by nanoplastics.

NIR-II fluorescent Ag2Se polystyrene beads in a lateral flow immunoassay to detect biomarkers for breast cancer.

Fluorescent lateral flow immunoassay (LFA), one tool in point of care testing (POCT) systems for breast cancer, has attracted attention because it is quick, simple, and convenient. However, samples and the constituent material exhibit autofluorescence in the visible region, which is a very large obstacle in the development of fluorescent LFAs. The autofluorescence of biological samples is scarcely found in the second near-infrared (NIR-II) range and samples scatter and absorb less NIR-II light than visible light. Here, we report an NIR-II QD-LFA platform using the NIR-II fluorescent Ag2Se quantum dots (QDs) with 1020 nm emission encapsulated into polystyrene beads as fluorescent probes. The NIR-II LFA platform was established to detect breast cancer tumour markers (CEA and CA153) within 15 min with a low limit of detection (CEA: 0.768 ng mL-1, CA153: 1.192 U mL-1), high recoveries (93.7% ~ 108.8%), and relative standard deviations (RSDs) of less than 10%. This study demonstrated the potential of NIR-II Ag2Se polystyrene beads as a fluorescent probe in LFA for rapid and accurate identification of biomarkers. They are suited for use in professional situations.

NIR quantum dot construction of a fluorescence anisotropy signal amplification biosensor for sensitive, rapid and separation-free detection of dopamine in serum.

Dopamine (DA) is an important small-molecule neurotransmitter, which is closely related to the development of many neurological diseases and has received increasing attention in the diagnosis of neurological diseases. Currently, the assays of the detection of dopamine such as electrochemical and colorimetric methods have low sensitivity, poor selectivity and susceptibility to interference, which limit the accurate quantification of dopamine. Fluorescence anisotropy immunoassay is a traditional analytical method in which the quantification is based on the change in fluorescence anisotropy values observed when fluorescence molecules are bound to a certain volume and mass of the material. Since dopamine is a small molecule with small volume and mass, we took advantage of the good photostability of the second near-infrared window (NIR-II) quantum dots (QDs) and the low spontaneous interference of the substrate, and designed a biosensor dopamine fluorescence anisotropy probe streptavidin biosensor (DFAP-SAB) based on the NIR-II QDs combined with streptavidin signal amplification to achieve rapid and separation-free detection of dopamine in human serum. The detection signal has a good linearity between 50 nM and 3000 nM with a detection limit of 11.2 nM. The application of NIR-II QDs provides the possibility of biosensor applications for complex samples. The construction of the streptavidin signal amplification device provides a new idea for small molecule detection.

Smartphone-Based Quantitative Detection of Ochratoxin A in Wheat via a Lateral Flow Assay.

Ochratoxin A (OTA) poses a severe health risk to livestock along the food chain. Moreover, according to the International Agency for Research on Cancer, it is also categorized as being possibly carcinogenic to humans. The lack of intelligent point-of-care test (POCT) methods restricts its early detection and prevention. This work establishes a smartphone-enabled point-of-care test for OTA detection via a fluorescent lateral flow assay within 6 min. By using a smartphone and portable reader, the assay allows for the recording and sharing of the detection results in a cloud database. This intelligent POCT provided (iPOCT) a linearity range of 0.1-3.0 ng/mL and a limit of detection (LOD) of 0.02 ng/mL (0.32 µg/kg in wheat). By spiking OTA in blank wheat samples, the recoveries were 89.1-120.4%, with a relative standard deviation (RSD) between 3.9-9.1%. The repeatability and reproducibility were 94.2-101.7% and 94.6-103.4%, respectively. This work provides a promising intelligent POCT method for food safety.

Rehabilitation of knee injury by chinese boxing / Reabilitação em lesão de joelho pelo boxe chinês / Rehabilitación de lesión de rodilla mediante el boxeo chino

ABSTRACT Introduction: Chinese boxing is a highly combative sport and injuries are inevitable. Rehabilitation of knee joint injuries can not only save the athlete's professional career but also improve their prevention ability. Objective: Study the situation of knee joint injuries in Chinese boxing and explore the strategies of sports rehabilitation. Methods: This experiment lasted 8 weeks. The knee joint activity and daily exercise ability of the control and experimental groups were tested. Results: In the experimental group, the knee joint extension range was increased to - 1.61° (± 2.228), the knee joint flexion range was increased to 97.14° (± 6.430), the walking ability score was increased to 32.25 (± 5.751) points, and the stair climbing and descending ability score was increased to 35.12 (± 8.764) points. The control group's scores were also optimized, but the range of optimization was smaller than that of the experimental group. Conclusion: Compared with traditional physical therapy and massage, sports rehabilitation training has a more significant effect on improving the range of motion and prevention ability on athletes' knee joints and should be promoted. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMO Introdução: O boxe chinês é um esporte altamente combativo e suas lesões são inevitáveis. A reabilitação de lesões nas articulações do joelho pode não apenas salvar a carreira profissional do atleta como também melhorar a sua capacidade de prevenção. Objetivo: Estudar a situação das lesões nas articulações do joelho pelo boxe chinês e explorar as estratégias de reabilitação esportiva. Métodos: Esta experiência teve duração de 8 semanas. A atividade articular do joelho e a capacidade de exercício diário dos grupos controle e experimental foram testadas. Resultados: No grupo experimental, o alcance da extensão da articulação do joelho foi aumentado para - 1,61° (± 2,228), o alcance da flexão da articulação do joelho foi aumentado para 97,14° (± 6,430), a pontuação da capacidade de caminhar foi aumentada para 32,25 (± 5,751) pontos, e a pontuação da capacidade de subir e descer escadas foi aumentada para 35,12 (± 8,764) pontos. Os índices do grupo de controle também foram otimizados, mas a faixa de otimização foi menor do que a do grupo experimental. Conclusão: Em comparação com a fisioterapia e massagem tradicionais, o treinamento de reabilitação esportiva tem um efeito mais significativo na melhoria da amplitude de movimento e na capacidade de prevenção sobre as articulações dos joelhos dos atletas, devendo ser promovido. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

RESUMEN Introducción: El boxeo chino es un deporte altamente combativo y sus lesiones son inevitables. La rehabilitación de las lesiones de la articulación de la rodilla no sólo puede salvar la carrera profesional del deportista, sino también mejorar su capacidad de prevención. Objetivo: Estudiar la situación de las lesiones de la articulación de la rodilla por el boxeo chino y explorar las estrategias de rehabilitación deportiva. Métodos: Este experimento duró 8 semanas. Se comprobó la actividad de la articulación de la rodilla y la capacidad de ejercicio diario de los grupos de control y experimental. Resultados: En el grupo experimental, el rango de extensión de la articulación de la rodilla aumentó a - 1,61° (± 2,228), el rango de flexión de la articulación de la rodilla aumentó a 97,14° (± 6,430), la puntuación de la capacidad de caminar aumentó a 32,25 (± 5,751) puntos, y la puntuación de la capacidad de subir y bajar escaleras aumentó a 35,12 (± 8,764) puntos. Las puntuaciones del grupo de control también se optimizaron, pero el rango de optimización fue menor que el del grupo experimental. Conclusión: En comparación con la fisioterapia tradicional y el masaje, el entrenamiento de rehabilitación deportiva tiene un efecto más significativo en la mejora de la amplitud de movimiento y la capacidad de prevención en las articulaciones de la rodilla de los atletas y debería promoverse. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

Heart rate monitoring in special training for boxers / Monitoramento de frequência cardíaca em treino especial para boxeadores / Monitorización de frecuencia cardíaca en entrenamiento especial para boxeadores

ABSTRACT Introduction Chinese boxing is an aggressive, competitive, and combative sport. During its performance, good physical fitness and a stable heart rate can determine the athletes' sports performance. Objective Study special physical training methods of Chinese boxing athletes by monitoring their heart rates. Methods The implementation period of the experiment totaled eight weeks, performed three times a week. The control group did not get any specific physical training while the experimental group received special physical training, properly protocoled. Their indices were measured before, during, and after the experiment, with classification and data analysis by Excel and SPSS software. Results The fitness data of the experimental group were significantly improved, with the heart rate more stable, corroborating the effectiveness of the special training. Conclusion The use of special physical training can optimize and better adjust the pre-existing protocol according to the athletes' real competition needs, improving the specialized physical fitness and the athletes' competitive level. It also helps stabilize the heart rate, helping athletes get better results in combat. Level of evidence II; Therapeutic studies - investigating treatment outcomes.

RESUMO Introdução O boxe chinês é um esporte agressivo, competitivo e combativo. Durante a sua execução, a boa forma física e a frequência cardíaca estável podem determinar o desempenho esportivo dos atletas. Objetivo Estudar métodos especiais de treinamento físico dos atletas de boxe chinês monitorando suas frequências cardíacas. Métodos O período de implementação do experimento totalizou oito semanas, executado três vezes por semana. O grupo de controle não obteve nenhum treinamento físico específico enquanto o grupo experimental recebeu um treinamento físico especial, devidamente protocolado. Seus índices foram mensurados antes, durante e depois do experimento, com classificação e análise de dados pelos programas Excel e SPSS. Resultados Os dados de aptidão física do grupo experimental foram significativamente aprimorados, com frequência cardíaca foi mais estável, corroborando a eficácia do treinamento especial. Conclusão O uso de treino físico especial pode otimizar e ajustar melhor o protocolo pré-existente, de acordo com as necessidades reais de competição dos atletas, melhorando a aptidão física especializada e o nível competitivo dos atletas. Também auxilia na estabilização da frequência cardíaca, ajudando os atletas a obterem melhores resultados em combate. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

RESUMEN Introducción El boxeo chino es un deporte agresivo, competitivo y combativo. Durante su ejecución, el buen estado físico y el ritmo cardíaco estable pueden determinar el rendimiento deportivo de los atletas. Objetivo Estudiar los métodos de entrenamiento físico especial de los atletas de boxeo chinos mediante la monitorización de sus frecuencias cardíacas. Métodos El periodo de aplicación del experimento fue de ocho semanas, realizado tres veces por semana. El grupo de control no obtuvo ningún entrenamiento físico específico, mientras que el grupo experimental recibió un entrenamiento físico especial, debidamente protocolizado. Se midieron sus índices antes, durante y después del experimento, con clasificación y análisis de datos mediante los programas Excel y SPSS. Resultados Los datos de aptitud física del grupo experimental mejoraron significativamente, con una frecuencia cardíaca más estable, lo que corrobora la eficacia del entrenamiento especial. Conclusión El uso del entrenamiento físico especial puede optimizar y ajustar mejor el protocolo preexistente, de acuerdo con las necesidades reales de competición de los atletas, mejorando la aptitud física especializada y el nivel competitivo de los atletas. También ayuda a estabilizar el ritmo cardíaco, ayudando a los atletas a obtener mejores resultados en el combate. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

Study on physical training in the lipid metabolism regulation of obese adolescents / Estudo sobre treinamento físico na regulação do metabolismo lipídico em adolescentes obesos / Estudio sobre el entrenamiento físico en la regulación del metabolismo lipídico en adolescentes obesos

ABSTRACT Introduction In proportion to the development of the economy, the problem of obesity among adolescents is also increasing. This abnormal lipid metabolism index can influence other physical diseases besides harming the social development of youth. Objective Investigate physical training and the regulation of lipid metabolism in adolescents, improving the metabolic index of obese youth. Methods 80 obese adolescents with equal numbers of both genders were randomly assigned into experimental and control groups. The experimental group received daily 80-min sports training (aerobics, walking, badminton, swimming, and other sports with low intensity and long duration) six times a week for one month, without distinction of exercise intensity or frequency for gender. A comparison method was performed between the groups before and after the intervention with indicators including body weight, BMI, fluid ratio, water measurement, waist, hip, skinfold thickness, FBG, CT, Tg, HDL - C, and LDL - C, among others. Results Physical training can effectively improve adolescents' body shape. Blood indices and other indicators except for HDL-C positively correlate with this body shape. Physical training substantially improved lipid metabolism in obese adolescents. Conclusion The exercise regimen of this experiment proved to be simple and manageable, offering adolescents a healthier physical and more confidence in their daily study, life, and social interaction, but also reducing several diseases caused by obesity. Due to the ease of replication, the sample size can be expanded to universal conclusions, making it feasible to popularize. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMO Introdução Proporcionalmente ao desenvolvimento da economia, aumenta também o problema da obesidade entre os adolescentes. Esse índice anormal no metabolismo lipídico pode influenciar outras doenças físicas além de prejudicar o desenvolvimento social na juventude. Objetivo Investigar o treinamento físico e a regulação do metabolismo lipídico em adolescentes, melhorando o índice metabólico dos jovens obesos. Métodos 80 adolescentes obesos com número igual de ambos os sexos foram distribuídos aleatoriamente em grupos controlados de experimento e controle. O grupo experimental recebeu treinamentos esportivos diários de 80 minutos (aeróbica, caminhada, badminton, natação e outros esportes com baixa intensidade e longa duração), seis vezes por semana durante um mês, sem distinção de intensidade ou frequência dos exercícios para os sexos. Foi realizado o método de comparação entre os grupos, antes e após a intervenção, com indicadores incluindo peso corporal, IMC, taxa de líquidos, medição de água, cintura, quadril, espessura de dobras cutâneas, FBG, CT, Tg, HDL - C, LDL - C entre outros. Resultados O treinamento físico pode melhorar efetivamente a forma corporal dos adolescentes. Índices sanguíneos e outros indicadores com exceção do HDL-C estão positivamente correlacionados com essa forma corporal. O treinamento físico melhorou substancialmente o metabolismo lipídico de adolescentes obesos. Conclusão O esquema de exercícios deste experimento demonstrou-se simples e viável, oferecendo aos adolescentes um físico mais saudável e mais confiança no processo de estudo diário, vida e interação social, mas também reduzir diversas doenças causadas pela obesidade. Devido a facilidade de replicação, o número de amostrar pode ser expandido para conclusões universais, viabilizando a sua popularização. Nível de evidência II; Estudos terapêuticos - investigação dos desfechos do tratamento.

RESUMEN Introducción Proporcionalmente al desarrollo de la economía, el problema de la obesidad entre los adolescentes también aumenta. Este índice anormal en el metabolismo lipídico puede influir en otras enfermedades físicas además de perjudicar el desarrollo social en la juventud. Objetivo Investigar el entrenamiento físico y la regulación del metabolismo lipídico en adolescentes, mejorando el índice metabólico de los jóvenes obesos. Métodos 80 adolescentes obesos con igual número de ambos sexos fueron distribuidos aleatoriamente en los grupos de experimento y de control. El grupo experimental recibió 80 minutos diarios de entrenamiento deportivo (aeróbic, marcha, bádminton, natación y otros deportes de baja intensidad y larga duración), seis veces a la semana durante un mes, sin distinción de intensidad o frecuencia de los ejercicios para los sexos. Se realizó un método de comparación entre los grupos, antes y después de la intervención, con indicadores que incluían el peso corporal, el IMC, la tasa de líquidos, la medición del agua, la cintura, la cadera, el grosor de los pliegues cutáneos, FBG, CT, Tg, HDL - C, LDL - C, entre otros. Resultados El entrenamiento físico puede mejorar eficazmente la forma corporal de los adolescentes. Los índices sanguíneos y otros indicadores, excepto el HDL-C, están positivamente correlacionados con esta forma corporal. El entrenamiento físico mejoró sustancialmente el metabolismo de los lípidos en los adolescentes obesos. Conclusión El esquema de ejercicios de este experimento demostró ser simple y factible, ofreciendo a los adolescentes un físico más saludable y más confianza en el proceso de estudio diario, la vida y la interacción social, pero también reduciendo varias enfermedades causadas por la obesidad. Debido a la facilidad de replicación, el tamaño de la muestra puede ampliarse para obtener conclusiones universales, lo que permite su popularización. Nivel de evidencia II; Estudios terapêuticos - investigación de los resultados del tratamiento.

Organic NIR-II dyes with ultralong circulation persistence for image-guided delivery and therapy.

Nanocarriers hold great promise for the controlled release of therapeutic payloads to target organs/tissues and extended duration of anticancer agents in the bloodstream. However, limited data on their in vivo pharmacokinetics and delivery process hamper clinical applications. Here we report a series of micellar nanocarriers self-assembled from new-generation thiophenthiadiazole (TTD)-based NIR-II fluorophores HLAnP (n = 1-4) for simultaneous bioimaging and drug delivery. The NIR-II HLA4P nanocarrier displays exceptional non-fouling performance, minimal immunogenicity, ultralong blood half-life, and high tumor accumulation even with different administration routes. When used as a drug carrier, HLA4P with encapsulated doxorubicin (DOX) realized accurate tumor targeting and continuous real-time in vivo NIR-II tracking of drug delivery and therapy, showing a sustained release rate, improved therapeutic effect, and diminished cardiotoxicity as compared to free DOX. This study provides a new perspective on the design of dual-functional NIR-II fluorophores for diagnostic and therapeutic applications.

A Second Near-Infrared Ru(II) Polypyridyl Complex for Synergistic Chemo-Photothermal Therapy.

The clinical success of cisplatin ushered in a new era of the application of metallodrugs. When it comes to practice, however, drug resistance, tumor recurrence, and drug systemic toxicity make it implausible to completely heal the patients. Herein, we successfully transform an electron acceptor [1, 2, 5]thiadiazolo[3,4-g]quinoxaline into a novel second near-infrared (NIR-II) fluorophore H7. After PEGylation and chelation, HL-PEG2k exhibits a wavelength bathochromic shift, enhanced photothermal conversion efficiency (41.77%), and an antineoplastic effect against glioma. Its potential for in vivo tumor tracking and image-guided chemo-photothermal therapy is explored. High levels of uptake and high-resolution NIR-II imaging results are thereafter obtained. The hyperthermia effect could disrupt the lysosomal membranes, which in turn aggravate the mitochondria dysfunction, arrest the cell cycle in the G2 phase, and finally lead to cancer cell apoptosis. HL-PEG2k displays a superior biocompatibility and thus can be a potential theranostic platform to combat the growth and recurrence of tumors.

Self-assembled NIR-II Fluorophores with Ultralong Blood Circulation for Cancer Imaging and Image-guided Surgery.

Complete excision of the last remaining 1-2% of tumor tissue without collateral damage remains particularly challenging. Herein, we report thiophenthiadiazole (TTD)-derived fluorophores L6-PEGnk (n = 1, 2, 5) as new-generation NIR-II (1000-1700 nm) probes with exceptional nonfouling performance and significantly high fluorescence quantum yields in water. L6-PEG2k can self-assemble into vesicular micelles and exhibited minimal immunogenicity, low binding affinities, ultralong blood circulation (t1/2 = 59.5 h), and a supercontrast ratio in vivo. Most importantly, L6-PEG2k achieved excellent in vivo CT-26 and U87MG tumor targeting and accumulation (>20 d) through intraperitoneal or intravenous injection. A subcutaneous U87MG tumor and orthotopic brain glioma were successfully resected under NIR-II FIGS in our animal model via intraperitoneal injection in an extended time window (48-144 h). This study highlights the potential of using L6-PEG2K as self-assembling molecular probes with long-circulation persistence for routine preoperative tumor assessment and precise intraoperative image-guided resection.

A near-infrared-II fluorescence anisotropy strategy for separation-free detection of adenosine triphosphate in complex media.

Fluorescence anisotropy (FA) has been widely applied for detecting and monitoring special targets in life sciences. However, matrix autofluorescence restricted its further application in complex biological samples. Herein, we report a near-infrared-II (NIR-II) FA strategy for detecting adenosine triphosphate (ATP) in human serum samples and breast cancer cell lysate, which employed NIR-II fluorescent Ag2Se quantum dots (QDs) as tags to reduce matrix autofluorescence effect and applied graphene oxide (GO) to enhance fluorescence anisotropy signals. In the presence of ATP, the recognition between NIR-II Ag2Se QDs labeled aptamer (QD-pDNA) and ATP led to the release of QD-pDNA from GO, resulting in the obvious decrease of FA values. ATP could be quantitatively detected in concentrations ranged from 3 nM to 2500 nM, with a detection limit down to 1.01 nM. This study showed that the developed NIR-II FA strategy could be applied for detecting targets in complex biological samples and had great potential for monitoring interactions between biomolecules in biomedical research.

Target-modulated sensitization of upconversion luminescence by NIR-emissive quantum dots: a new strategy to construct upconversion biosensors.

We herein used Ag2Se quantum dots (QDs) as a target-modulated sensitizer for upconversion nanoparticles (UCNPs) and the target thrombin as the sensitizing switch to construct a biosensor, circumventing the limited luminescence resonance energy transfer (LRET) efficiency of UCNPs, with enhanced signal-to-background ratio (SBR) and assay sensitivity.

Bacteria photosensitized by intracellular gold nanoclusters for solar fuel production.

The demand for renewable and sustainable fuel has prompted the rapid development of advanced nanotechnologies to effectively harness solar power. The construction of photosynthetic biohybrid systems (PBSs) aims to link preassembled biosynthetic pathways with inorganic light absorbers. This strategy inherits both the high light-harvesting efficiency of solid-state semiconductors and the superior catalytic performance of whole-cell microorganisms. Here, we introduce an intracellular, biocompatible light absorber, in the form of gold nanoclusters (AuNCs), to circumvent the sluggish kinetics of electron transfer for existing PBSs. Translocation of these AuNCs into non-photosynthetic bacteria enables photosynthesis of acetic acid from CO2. The AuNCs also serve as inhibitors of reactive oxygen species (ROS) to maintain high bacterium viability. With the dual advantages of light absorption and biocompatibility, this new generation of PBS can efficiently harvest sunlight and transfer photogenerated electrons to cellular metabolism, realizing CO2 fixation continuously over several days.

Gd-DTPA-coupled Ag2Se quantum dots for dual-modality magnetic resonance imaging and fluorescence imaging in the second near-infrared window.

Near-infrared (NIR) fluorescent quantum dots (QDs) are ideal platforms to fabricate multifunctional contrast agents for multimodal imaging. Herein, second near-infrared window fluorescent (NIR-II) Ag2Se QDs were coupled with gadopentetate dimeglumine injection (Gd-DTPA) for dual-modality T1-weighted magnetic resonance (MR) imaging and fluorescence imaging. In vitro experiments suggested that the prepared Ag2Se-Gd QDs exhibit low cytotoxicity, remarkable T1-weighted MR imaging, and fluorescence imaging contrast properties. In vivo experiment results showed that Ag2Se-Gd QDs were the preferred contrast agents for dual-modality T1-weighted MR imaging and fluorescence imaging with high spatial resolution. Moreover, excellent temporal resolution and high tissue penetration depth were also achieved by fluorescence imaging. These results indicate the potential of Ag2Se-Gd QDs as multifunctional contrast agents for multimodal imaging in clinical diagnosis and research.

Ultrasmall Pb:Ag2 S Quantum Dots with Uniform Particle Size and Bright Tunable Fluorescence in the NIR-II Window.

Ag2 S quantum dots (QDs) are well-known near-infrared fluorophores and have attracted great interest in biomedical labeling and imaging in the past years. However, their photoluminescence efficiency is hard to compete with Cd-, Pb-based QDs. The high Ag+ mobility in Ag2 S crystal, which causes plenty of cation deficiency and crystal defects, may be responsible mainly for the low photoluminescence quantum yield (PLQY) of Ag2 S QDs. Herein, a cation-doping strategy is presented via introducing a certain dosage of transition metal Pb2+ ions into Ag2 S nanocrystals to mitigate this intrinsic shortcoming. The Pb-doped Ag2 S QDs (designated as Pb:Ag2 S QDs) present a renovated crystal structure and significantly enhanced optical performance. Moreover, by simply adjusting the levels of Pb doping in the doped nanocrystals, Pb:Ag2 S QDs with bright emission (PLQY up to 30.2%) from 975 to 1242 nm can be prepared without altering the ultrasmall particle size (≈2.7-2.8 nm). Evidently, this cation-doping strategy facilitates both the renovation of crystal structure of Ag2 S QDs and modulation of their optical properties.

Controllable synthesis of nanocrystals in droplet reactors.

In recent years, a broad range of nanocrystals have been synthesized in droplet-based microfluidic reactors which provide obvious advantages, such as accurate manipulation, better reproducibility and reliable automation. In this review, we initially introduce general concepts of droplet reactors followed by discussions of their main functional regions including droplet generation, mixing of reactants, reaction controlling, in situ monitoring, and reaction quenching. Subsequently, the enhanced mass and heat transport properties are discussed. Next, we focus on research frontiers including sequential multistep synthesis, intelligent synthesis, reliable scale-up synthesis, and interfacial synthesis. Finally, we end with an outlook on droplet reactors, especially highlighting some aspects such as large-scale production, the integrated process of synthesis and post-synthetic treatments, automated droplet reactors with in situ monitoring and optimizing algorithms, and rapidly developing strategies for interfacial synthesis.

Real-Time Dissection of Distinct Dynamin-Dependent Endocytic Routes of Influenza A Virus by Quantum Dot-Based Single-Virus Tracking.

Entry is the first critical step for the infection of influenza A virus and of great significance for the research and development of antiflu drugs. Influenza A virus depends on exploitation of cellular endocytosis to enter its host cells, and its entry behaviors in distinct routes still need further investigation. With the aid of a single-virus tracking technique and quantum dots, we have realized real-time and multicolor visualization of the endocytic process of individual viruses and comprehensive dissection of two distinct dynamin-dependent endocytic pathways of influenza A virus, either dependent on clathrin or not. Based on the sequential progression of protein recruitment and viral motility, we have revealed the asynchronization in the recruitments of clathrin and dynamin during clathrin-dependent entry of the virus, with a large population of events for short-lived recruitments of these two proteins being abortive. In addition, the differentiated durations of dynamin recruitment and responses to inhibitors in these two routes have evidenced somewhat different roles of dynamin. Besides promoting membrane fission in both entry routes, dynamin also participates in the maturation of a clathrin-coated pit in the clathrin-dependent route. Collectively, the current study displays a dynamic and precise image of the entry process of influenza A virus and elucidates the mechanisms of distinct entry routes. This quantum dot-based single-virus tracking technique is proven to be well-suited for investigating the choreographed interactions between virus and cellular proteins.

Near-Infrared Fluorescent Ag2 Se-Cetuximab Nanoprobes for Targeted Imaging and Therapy of Cancer.

Theranostic nanoprobes integrated with diagnostic imaging and therapy capabilities have shown great potential for highly effective tumor therapy by realizing imaging-guided drug delivery and tumor treatment. Developing novel high-performance nanoprobes is an important basis for tumor theranostic application. Here, near-infrared (NIR) fluorescent and low-biotoxicity Ag2 Se quantum dots (QDs) have been coupled with cetuximab, a clinical antiepidermal growth factor receptor antibody drug for tumor therapy, via a facile bioconjugation strategy to prepare multifunctional Ag2 Se-cetuximab nanoprobes. Compared with the Ag2 Se QDs alone, the Ag2 Se-cetuximab nanoprobes display faster and more enrichment at the site of orthotopic tongue cancer, and thus present better NIR fluorescence contrast between the tumor and the surrounding regions. At 24 h postinjection, the NIR fluorescence of Ag2 Se-cetuximab nanoprobes at the tumor site is still easily detectable, whereas no fluorescence is observed for the Ag2 Se QDs. Moreover, the Ag2 Se-cetuximab nanoprobes have also significantly inhibited the tumor growth and improved the survival rate of orthotopic tongue cancer-bearing nude mice from 0% to 57.1%. Taken together, the constructed multifunctional Ag2 Se-cetuximab nanoprobes have achieved combined targeted imaging and therapy of orthotopic tongue cancer, which may greatly contribute to the development of nanotheranostics.