Preparing Better Samples for Cryo-Electron Microscopy: Biochemical Challenges Do Not End with Isolation and Purification.

The preparation of extremely thin samples, which are required for high-resolution electron microscopy, poses extreme risk of damaging biological macromolecules due to interactions with the air-water interface. Although the rapid increase in the number of published structures initially gave little indication that this was a problem, the search for methods that substantially mitigate this hazard is now intensifying. The two main approaches under investigation are (a) immobilizing particles onto structure-friendly support films and (b) reducing the length of time during which such interactions may occur. While there is little possibility of outrunning diffusion to the interface, intentional passivation of the interface may slow the process of adsorption and denaturation. In addition, growing attention is being given to gaining more effective control of the thickness of the sample prior to vitrification.

The integral role of de novo lipogenesis in the preparation for seasonal dormancy.

Animals can alter their body compositions in anticipation of dormancy to endure seasons with limited food availability. Accumulation of lipid reserves, mostly in the form of triglycerides (TAGs), is observed during the preparation for dormancy in diverse animals, including insects (diapause) and mammals (hibernation). However, the mechanisms involved in the regulation of lipid accumulation and the ecological consequences of failure to accumulate adequate lipid stores in preparation for animal dormancy remain understudied. In the broadest sense, lipid reserves can be accumulated in two ways: the animal either receives lipids directly from the environment or converts the sugars and amino acids present in food to fatty acids through de novo lipogenesis and then to TAGs. Here, we show that preparation for diapause in the Colorado potato beetle (Leptinotarsa decemlineata) involves orchestrated upregulation of genes involved in lipid metabolism with a transcript peak in 8- and 10-d-old diapause-destined insects. Regulation at the transcript abundance level was associated with the accumulation of substantial fat stores. Furthermore, the knockdown of de novo lipogenesis enzymes (ACCase and FAS-1) prolonged the preparatory phase, while the knockdown of fatty acid transportation genes shortened the preparatory phase. Our findings suggest a model in which the insects dynamically decide when to transition from the preparation phase into diapause, depending on the progress in lipid accumulation through de novo lipogenesis.

Graphene sandwich-based biological specimen preparation for cryo-EM analysis.

High-quality specimen preparation plays a crucial role in cryo-electron microscopy (cryo-EM) structural analysis. In this study, we have developed a reliable and convenient technique called the graphene sandwich method for preparing cryo-EM specimens. This method involves using two layers of graphene films that enclose macromolecules on both sides, allowing for an appropriate ice thickness for cryo-EM analysis. The graphene sandwich helps to mitigate beam-induced charging effect and reduce particle motion compared to specimens prepared using the traditional method with graphene support on only one side, therefore improving the cryo-EM data quality. These advancements may open new opportunities to expand the use of graphene in the field of biological electron microscopy.

Current concepts, advances, and challenges in deciphering the human microbiota with metatranscriptomics.

Metatranscriptomics refers to the analysis of the collective microbial transcriptome of a sample. Its increased utilization for the characterization of human-associated microbial communities has enabled the discovery of many disease-state related microbial activities. Here, we review the principles of metatranscriptomics-based analysis of human-associated microbial samples. We describe strengths and weaknesses of popular sample preparation, sequencing, and bioinformatics approaches and summarize strategies for their use. We then discuss how human-associated microbial communities have recently been examined and how their characterization may change. We conclude that metatranscriptomics insights into human microbiotas under health and disease have not only expanded our knowledge on human health, but also opened avenues for rational antimicrobial drug use and disease management.

Differential Formation of Motor Cortical Dynamics during Movement Preparation According to the Predictability of Go Timing.

The motor cortex not only executes but also prepares movement, as motor cortical neurons exhibit preparatory activity that predicts upcoming movements. In movement preparation, animals adopt different strategies in response to uncertainties existing in nature such as the unknown timing of when a predator will attack-an environmental cue informing "go." However, how motor cortical neurons cope with such uncertainties is less understood. In this study, we aim to investigate whether and how preparatory activity is altered depending on the predictability of "go" timing. We analyze firing activities of the anterior lateral motor cortex in male mice during two auditory delayed-response tasks each with predictable or unpredictable go timing. When go timing is unpredictable, preparatory activities immediately reach and stay in a neural state capable of producing movement anytime to a sudden go cue. When go timing is predictable, preparation activity reaches the movement-producible state more gradually, to secure more accurate decisions. Surprisingly, this preparation process entails a longer reaction time. We find that as preparatory activity increases in accuracy, it takes longer for a neural state to transition from the end of preparation to the start of movement. Our results suggest that the motor cortex fine-tunes preparatory activity for more accurate movement using the predictability of go timing.

µPhos: a scalable and sensitive platform for high-dimensional phosphoproteomics.

Mass spectrometry has revolutionized cell signaling research by vastly simplifying the analysis of many thousands of phosphorylation sites in the human proteome. Defining the cellular response to perturbations is crucial for further illuminating the functionality of the phosphoproteome. Here we describe µPhos ('microPhos'), an accessible phosphoproteomics platform that permits phosphopeptide enrichment from 96-well cell culture and small tissue amounts in <8 h total processing time. By greatly minimizing transfer steps and liquid volumes, we demonstrate increased sensitivity, >90% selectivity, and excellent quantitative reproducibility. Employing highly sensitive trapped ion mobility mass spectrometry, we quantify ~17,000 Class I phosphosites in a human cancer cell line using 20 µg starting material, and confidently localize ~6200 phosphosites from 1 µg. This depth covers key signaling pathways, rendering sample-limited applications and perturbation experiments with hundreds of samples viable. We employ µPhos to study drug- and time-dependent response signatures in a leukemia cell line, and by quantifying 30,000 Class I phosphosites in the mouse brain we reveal distinct spatial kinase activities in subregions of the hippocampal formation.

An Automated Nanowell-Array Workflow for Quantitative Multiplexed Single-Cell Proteomics Sample Preparation at High Sensitivity.

Multiplexed and label-free mass spectrometry-based approaches with single-cell resolution have attributed surprising heterogeneity to presumed homogenous cell populations. Even though specialized experimental designs and instrumentation have demonstrated remarkable advances, the efficient sample preparation of single cells still lags. Here, we introduce the proteoCHIP, a universal option for single-cell proteomics sample preparation including multiplexed labeling up to 16-plex with high sensitivity and throughput. The automated processing using a commercial system combining single-cell isolation and picoliter dispensing, the cellenONE, reduces final sample volumes to low nanoliters submerged in a hexadecane layer simultaneously eliminating error-prone manual sample handling and overcoming evaporation. The specialized proteoCHIP design allows direct injection of single cells via a standard autosampler resulting in around 1500 protein groups per TMT10-plex with reduced or eliminated need for a carrier proteome. We evaluated the effect of wider precursor isolation windows at single-cell input levels and found that using 2 Da isolation windows increased overall sensitivity without significantly impacting interference. Using the dedicated mass spectrometry acquisition strategies detailed here, we identified on average close to 2000 proteins per TMT10-plex across 170 multiplexed single cells that readily distinguished human cell types. Overall, our workflow combines highly efficient sample preparation, chromatographic and ion mobility-based filtering, rapid wide-window data-dependent acquisition analysis, and intelligent data analysis for optimal multiplexed single-cell proteomics. This versatile and automated proteoCHIP-based sample preparation approach is sufficiently sensitive to drive biological applications of single-cell proteomics and can be readily adopted by proteomics laboratories.

Preparing Patients for Oral Immunotherapy (PPOINT): International Delphi consensus for procedural preparation and consent.

BACKGROUND: Despite the promise of oral immunotherapy (OIT) to treat food allergies, this procedure is associated with potential risk. There is no current agreement about what elements should be included in the preparatory or consent process. OBJECTIVE: We developed consensus recommendations about the OIT process considerations and patient-specific factors that should be addressed before initiating OIT and developed a consensus OIT consent process and information form. METHODS: We convened a 36-member Preparing Patients for Oral Immunotherapy (PPOINT) panel of allergy experts to develop a consensus OIT patient preparation, informed consent process, and framework form. Consensus for themes and statements was reached using Delphi methodology, and the consent information form was developed. RESULTS: The expert panel reached consensus for 4 themes and 103 statements specific to OIT preparatory procedures, of which 76 statements reached consensus for inclusion specific to the following themes: general considerations for counseling patients about OIT; patient- and family-specific factors that should be addressed before initiating OIT and during OIT; indications for initiating OIT; and potential contraindications and precautions for OIT. The panel reached consensus on 9 OIT consent form themes: benefits, risks, outcomes, alternatives, risk mitigation, difficulties/challenges, discontinuation, office policies, and long-term management. From these themes, 219 statements were proposed, of which 189 reached consensus, and 71 were included on the consent information form. CONCLUSION: We developed consensus recommendations to prepare and counsel patients for safe and effective OIT in clinical practice with evidence-based risk mitigation. Adoption of these recommendations may help standardize clinical care and improve patient outcomes and quality of life.

Matrix-Free Thermally Activated Delayed Fluorescent Carbon Dots-Based Electroluminescent Light-Emitting Diodes Exceeding 5.6% External Quantum Efficiency.

Carbon dots (CDs) are promising luminescent emission layer materials for next generation electroluminescent light emitting diodes (EL-LEDs) due to their many advantages, such as environmental friendliness, low cost, and high stability. However, limited by the spin-forbidden properties of the triplet transition, it is difficult to improve the external quantum efficiency (EQE) of fluorescent CDs-based EL-LEDs. Meanwhile, traditional thermally activated delayed fluorescent (TADF) CDs prepared using coating strategies are difficult to utilize in EL-LEDs due to the nonconductivity of the coating agent. Herein, we successfully developed matrix-free TADF CDs with yellow emission and achieved a device EQE of 5.68%, which is the highest value reported in CDs-based EL-LEDs. In addition, we also developed white EL-LEDs with an EQE of 1.70%. This study highlights the importance of interactions between precursors in modulating the electroluminescence properties of TADF emitters and provides an effective design principle for matrix-free TADF CDs.

HowDirty: An R package to evaluate molecular contaminants in LC-MS experiments.

Contaminants derived from consumables, reagents, and sample handling often negatively affect LC-MS data acquisition. In proteomics experiments, they can markedly reduce identification performance, reproducibility, and quantitative robustness. Here, we introduce a data analysis workflow combining MS1 feature extraction in Skyline with HowDirty, an R-markdown-based tool, that automatically generates an interactive report on the molecular contaminant level in LC-MS data sets. To facilitate the interpretation of the results, the HTML report is self-contained and self-explanatory, including plots that can be easily interpreted. The R package HowDirty is available from https://github.com/DavidGZ1/HowDirty. To demonstrate a showcase scenario for the application of HowDirty, we assessed the impact of ultrafiltration units from different providers on sample purity after filter-assisted sample preparation (FASP) digestion. This allowed us to select the filter units with the lowest contamination risk. Notably, the filter units with the lowest contaminant levels showed higher reproducibility regarding the number of peptides and proteins identified. Overall, HowDirty enables the efficient evaluation of sample quality covering a wide range of common contaminant groups that typically impair LC-MS analyses, facilitating corrective or preventive actions to minimize instrument downtime.

Assessing the precision of a detergent-assisted cartridge precipitation workflow for non-targeted quantitative proteomics.

Detergent-based workflows incorporating sodium dodecyl sulfate (SDS) necessitate additional steps for detergent removal ahead of mass spectrometry (MS). These steps may lead to variable protein recovery, inconsistent enzyme digestion efficiency, and unreliable MS signals. To validate a detergent-based workflow for quantitative proteomics, we herein evaluate the precision of a bottom-up sample preparation strategy incorporating cartridge-based protein precipitation with organic solvent to deplete SDS. The variance of data-independent acquisition (SWATH-MS) data was isolated from sample preparation error by modelling the variance as a function of peptide signal intensity. Our SDS-assisted cartridge workflow yield a coefficient of variance (CV) of 13%-14%. By comparison, conventional (detergent-free) in-solution digestion increased the CV to 50%; in-gel digestion provided lower CVs between 14% and 20%. By filtering peptides predicting to display lower precision, we further enhance the validity of data in global comparative proteomics. These results demonstrate the detergent-based precipitation workflow is a reliable approach for in depth, label-free quantitative proteome analysis.

Proactive Interhemispheric Disinhibition Supports Response Preparation during Selective Stopping.

Response inhibition is essential for terminating inappropriate actions. A substantial response delay may occur in the nonstopped effector when only part of a multieffector action is terminated. This stopping-interference effect has been attributed to nonselective response inhibition processes and can be reduced with proactive cuing. This study aimed to elucidate the role of interhemispheric primary motor cortex (M1-M1) influences during selective stopping with proactive cuing. We hypothesized that stopping-interference would be reduced as stopping certainty increased because of proactive recruitment of interhemispheric facilitation or inhibition when cued to respond or stop, respectively. Twenty-three healthy human participants of either sex performed a bimanual anticipatory response inhibition paradigm with cues signaling the likelihood of a stop-signal occurring. Dual-coil transcranial magnetic stimulation was used to determine corticomotor excitability (CME), interhemispheric inhibition (IHI), and interhemispheric facilitation (IHF) in the left hand at rest and during response preparation. Response times slowed and stopping-interference decreased with increased stopping certainty. Proactive response inhibition was marked by a reduced rate of rise and faster cancel time in electromyographical bursts during stopping. There was a nonselective release of IHI but not CME from rest to in-task response preparation, whereas IHF was not observed in either context. An effector-specific reduction in CME but no reinstatement of IHI was observed when the left hand was cued to stop. These findings indicate that stopping speed and selectivity are better with proactive cueing and that interhemispheric M1-M1 channels modulate inhibitory tone during response preparation to support going but not proactive response inhibition.SIGNIFICANCE STATEMENT Response inhibition is essential for terminating inappropriate actions and, in some cases, may be required for only part of a multieffector action. The present study examined interhemispheric influences between the primary motor cortices during selective stopping with proactive cuing. Stopping selectivity was greater with increased stopping certainty and was marked by proactive adjustments to the hand cued to stop and hand cued to respond separately. Inhibitory interhemispheric influences were released during response preparation but were not directly involved in proactive response inhibition. These findings indicate that between-hand stopping can be selective with proactive cuing, but cue-related improvements are unlikely to reflect the advance engagement of interhemispheric influences between primary motor cortices.

ChipFilter: Microfluidic-Based Comprehensive Sample Preparation Methodology for Microbial Consortia.

The metaproteomic approach is an attractive way to describe a microbiome at the functional level, allowing the identification and quantification of proteins across a broad dynamic range as well as the detection of post-translational modifications. However, it remains relatively underutilized, mainly due to technical challenges that should be addressed, including the complexity of extracting proteins from heterogeneous microbial communities. Here, we show that a ChipFilter microfluidic device coupled to a liquid chromatography tandem mass spectrometry (LC-MS/MS) setup can be successfully used for the identification of microbial proteins. Using cultures of Escherichia coli, Bacillus subtilis, and Saccharomyces cerevisiae, we have shown that it is possible to directly lyse the cells and digest the proteins in the ChipFilter to allow the identification of a higher number of proteins and peptides than that by standard protocols, even at low cell density. The peptides produced are overall longer after ChipFilter digestion but show no change in their degree of hydrophobicity. Analysis of a more complex mixture of 17 species from the gut microbiome showed that the ChipFilter preparation was able to identify and estimate the amounts of 16 of these species. These results show that ChipFilter can be used for the proteomic study of microbiomes, particularly in the case of a low volume or cell density. The mass spectrometry data have been deposited on the ProteomeXchange Consortium via the PRIDE partner repository with the data set identifier PXD039581.

A Rapid One-Pot Workflow for Sensitive Microscale Phosphoproteomics.

Compared to advancements in single-cell proteomics, phosphoproteomics sensitivity has lagged behind due to low abundance, complex sample preparation, and substantial sample input requirements. We present a simple and rapid one-pot phosphoproteomics workflow (SOP-Phos) integrated with data-independent acquisition mass spectrometry (DIA-MS) for microscale phosphoproteomic analysis. SOP-Phos adapts sodium deoxycholate based one-step lysis, reduction/alkylation, direct trypsinization, and phosphopeptide enrichment by TiO2 beads in a single-tube format. By reducing surface adsorptive losses via utilizing n-dodecyl ß-d-maltoside precoated tubes and shortening the digestion time, SOP-Phos is completed within 3-4 h with a 1.4-fold higher identification coverage. SOP-Phos coupled with DIA demonstrated >90% specificity, enhanced sensitivity, lower missing values (<1%), and improved reproducibility (8%-10% CV). With a sample size-comparable spectral library, SOP-Phos-DIA identified 33,787 ± 670 to 22,070 ± 861 phosphopeptides from 5 to 0.5 µg cell lysate and 30,433 ± 284 to 6,548 ± 21 phosphopeptides from 50,000 to 2,500 cells. Such sensitivity enabled mapping key lung cancer signaling sites, such as EGFR autophosphorylation sites Y1197/Y1172 and drug targets. The feasibility of SOP-Phos-DIA was demonstrated on EGFR-TKI sensitive and resistant cells, revealing the interplay of multipathway Hippo-EGFR-ERBB signaling cascades underlying the mechanistic insight into EGFR-TKI resistance. Overall, SOP-Phos-DIA is an efficient and robust protocol that can be easily adapted in the community for microscale phosphoproteomic analysis.

A single workflow for multi-species blood transcriptomics.

BACKGROUND: Blood transcriptomic analysis is widely used to provide a detailed picture of a physiological state with potential outcomes for applications in diagnostics and monitoring of the immune response to vaccines. However, multi-species transcriptomic analysis is still a challenge from a technological point of view and a standardized workflow is urgently needed to allow interspecies comparisons. RESULTS: Here, we propose a single and complete total RNA-Seq workflow to generate reliable transcriptomic data from blood samples from humans and from animals typically used in preclinical models. Blood samples from a maximum of six individuals and four different species (rabbit, non-human primate, mouse and human) were extracted and sequenced in triplicates. The workflow was evaluated using different wet-lab and dry-lab criteria, including RNA quality and quantity, the library molarity, the number of raw sequencing reads, the Phred-score quality, the GC content, the performance of ribosomal-RNA and globin depletion, the presence of residual DNA, the strandness, the percentage of coding genes, the number of genes expressed, and the presence of saturation plateau in rarefaction curves. We identified key criteria and their associated thresholds to be achieved for validating the transcriptomic workflow. In this study, we also generated an automated analysis of the transcriptomic data that streamlines the validation of the dataset generated. CONCLUSIONS: Our study has developed an end-to-end workflow that should improve the standardization and the inter-species comparison in blood transcriptomics studies. In the context of vaccines and drug development, RNA sequencing data from preclinical models can be directly compared with clinical data and used to identify potential biomarkers of value to monitor safety and efficacy.

From preparation to post-processing: Insights into evoked and induced cortical activity during pre-cued motor reactions in children and adolescents.

INTRODUCTION: The motor system undergoes significant development throughout childhood and adolescence. The contingent negative variation (CNV), a brain response reflecting preparation for upcoming actions, offers valuable insights into these changes. However, previous CNV studies of motor preparation have primarily focused on adults, leaving a gap in our understanding of how cortical activity related to motor planning and execution matures in children and adolescents. METHODS: The study addresses this gap by investigating the maturation of motor preparation, pre-activation, and post-processing in 46 healthy, right-handed children and adolescents aged 5-16 years. To overcome the resolution limitations of previous studies, we combined 64-electrode high-density Electroencephalography (EEG) and advanced analysis techniques, such as event-related potentials (ERPs), mu-rhythm desynchronization as well as source localization approaches. The combined analyses provided an in-depth understanding of cortical activity during motor control. RESULTS: Our data showed that children exhibited prolonged reaction times, increased errors, and a distinct pattern of cortical activation compared to adolescents. The findings suggest that the supplementary motor area (SMA) plays a progressively stronger role in motor planning and response evaluation as children age. Additionally, we observe a decrease in sensory processing and post-movement activity with development, potentially reflecting increased efficiency. Interestingly, adolescent subjects, unlike young adults in previous studies, did not yet show contralateral activation of motor areas during the motor preparation phase (late CNV). CONCLUSION: The progressive increase in SMA activation and distinct cortical activation patterns in younger participants suggest immature motor areas. These immature regions might be a primary cause underlying the age-related increase in motor action control efficiency. Additionally, the study demonstrates a prolonged maturation of cortical motor areas, extending well into early adulthood, challenging the assumption that motor control is fully developed by late adolescence. This research, extending fundamental knowledge of motor control development, offers valuable insights that lay the foundation for understanding and treating motor control difficulties.

Early and late contingent negative variation (CNV) reflect different aspects of deficits in schizophrenia.

Abnormal reward processing and psychomotor slowing are well-known in schizophrenia (SZ). As a slow frontocentral potential, contingent negative variation (CNV) is associated with anticipatory attention, motivation and motor planning. The present study aims to evaluate the early and late amplitude and latencies of CNV in patients with SZ compared to healthy controls during a reward processing task and to show its association with clinical symptoms. We recruited 21 patients with SZ and 22 healthy controls to compare early and late CNV amplitude and latency values during a Monetary Incentive Delay (MID) Task between groups. Patients' symptom severity, levels of negative symptoms and depressive symptoms were assessed. Clinical features of the patients were further examined for their relation with CNV components. In conclusion, we found decreased early CNV amplitudes in SZ during the reward condition. They also displayed diminished and shortened late CNV responses for incentive cues, specifically at the central location. Furthermore, early CNV amplitudes exhibited a significant correlation with positive symptoms. Both CNV latencies were linked with medication dosage and the behavioural outcomes of the MID task. We revealed that early and late CNV exhibit different functions in neurophysiology and correspond to various facets of the deficits observed in patients. Our findings also emphasized that slow cortical potentials are indicative of deficient motivational processes as well as impaired reaction preparation in SZ. To gain a deeper understanding of the cognitive and motor impairments associated with psychosis, future studies must compare the effects of CNV in the early and late phases.

Interhemispheric inhibition between dorsal premotor and primary motor cortices is released during preparation of unimanual but not bimanual movements.

Previous research applying transcranial magnetic stimulation during unimanual reaction time tasks indicates a transient change in the inhibitory influence of the dorsal premotor cortex over the contralateral primary motor cortex shortly after the presentation of an imperative stimulus. The degree of interhemispheric inhibition from the dorsal premotor cortex to the contralateral primary motor cortex shifts depending on whether the targeted effector representation in the primary motor cortex is selected for movement. Further, the timing of changes in inhibition covaries with the selection demands of the reaction time task. Less is known about modulation of dorsal premotor to primary motor cortex interhemispheric inhibition during the preparation of bimanual movements. In this study, we used a dual coil transcranial magnetic stimulation to measure dorsal premotor to primary motor cortex interhemispheric inhibition between both hemispheres during unimanual and bimanual simple reaction time trials. Interhemispheric inhibition was measured early and late in the 'pre-movement period' (defined as the period immediately after the onset of the imperative stimulus and before the beginning of voluntary muscle activity). We discovered that interhemispheric inhibition was more facilitatory early in the pre-movement period compared with late in the pre-movement period during unimanual reaction time trials. In contrast, interhemispheric inhibition was unchanged throughout the pre-movement period during symmetrical bimanual reaction time trials. These results suggest that there is greater interaction between the dorsal premotor cortex and contralateral primary motor cortex during the preparation of unimanual actions compared to bimanual actions.

Huang Qin decoction increases SLC6A4 expression and blocks the NFκB-mediated NLRP3/Caspase1/GSDMD pathway to disrupt colitis-associated carcinogenesis.

Huang Qin decoction (HQD) is a traditional Chinese medicine formula for treating colitis, but the effects and molecular mechanism of action of HQD in colitis-associated carcinogenesis (CAC) are still unclear. Therefore, we aimed to determine the beneficial effects of HQD on CAC in mice and to reveal the underlying mechanism involved. AOM/DSS was used to induce CAC in mice, and the effects of HQD on tumorigenesis in mice were examined (with mesalazine serving as a positive control). Mesalazine or HQD treatment alleviated body weight loss and decreased the disease activity index in mice induced by AOM/DSS. Mesalazine or HQD treatment also suppressed the shortening of colon tissue length, the number of tumors, and the infiltration of inflammatory cells. The genes targeted by HQD were predicted and verified, followed by knockout experiments. Elevated SLC6A4 and inhibited serotonin production and inflammation were observed in HQD-treated mice. HQD inhibited the NFκB and NLRP3/caspase1/GSDMD pathways. The therapeutic effect of HQD was diminished in SLC6A4-deficient AOM/DSS mice. Additionally, the downregulation of SLC6A4 mitigated the inhibitory effect of HQD-containing serum on MODE-K cell pyroptosis. Our findings suggest that SLC6A4 is a pivotal regulator of HQD-alleviated CAC via its modulation of the NLRP3/caspase1/GSDMD pathway.

Comprehensive Overview of Controlled Fabrication of Multifunctional Fluorescent Carbon Quantum Dots and Exploring Applications.

In recent years, carbon dots (CDs) have garnered increasing attention due to their simple preparation methods, versatile performances, and wide-ranging applications. CDs can manifest various optical, physical, and chemical properties including quantum yield (QY), emission wavelength (Em), solid-state fluorescence (SSF), room-temperature phosphorescence (RTP), material-specific responsivity, pH sensitivity, anti-oxidation and oxidation, and biocompatibility. These properties can be effectively regulated through precise control of the CD preparation process, rendering them suitable for diverse applications. However, the lack of consideration given to the precise control of each feature of CDs during the preparation process poses a challenge in obtaining the requisite features for various applications. This paper is to analyze existing research and present novel concepts and ideas for creating CDs with different distinct features and applications. The synthesis methods of CDs are discussed in the first section, followed by a comprehensive overview of the important properties of CDs and the modification strategy. Subsequently, the application of CDs and their requisite properties are reviewed. Finally, the paper outlines the current challenges in controlling CDs properties and their applications, discusses potential solutions, and offers suggestions for future research.