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1.
JDR Clin Trans Res ; 9(2): 104-113, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37542374

ABSTRACT

INTRODUCTION: Patient values and preferences (PVP) are among multiple sources of information panelists synthesize when developing clinical practice guidelines (CPG). Patient and public involvement (PPI) can be critical for learning PVP; however, the methodology for engaging patients in CPG development is lacking. Deliberative engagement is effective for obtaining public views on complex topics that require people to consider ethics, values, and competing perspectives. OBJECTIVE: Elicit comprehensive understanding of PVP concerning oral analgesics for managing acute dental pain consecutive to toothache and simple and surgical dental extractions, with consideration of associated outcomes, both desirable and undesirable. METHODS: Multistage engagement involving 2 electronic surveys and a 90-min online small group deliberative engagement. Adults who have experienced acute dental pain deliberated about 3 hypothetical scenarios stratified according to expected pain intensity, completed a postdeliberation survey, and validated a PVP statement developed by researchers based on review of qualitative data from deliberations and quantitative data from surveys. RESULTS: Participants affirmed the PVP statement reflected their small group deliberations and their individual views. Most indicated that pain relief is critical to deciding which pain relief medicine they would want regardless of expected pain level. Most also identify as critical concerns about substance abuse or misuse, although many believe it unlikely that they will experience these outcomes over the brief prescription timeframe for acute dental pain. Participants identified agency in decision-making, consultation including "better communication" of options, and treatment actions tailored to life circumstances as key values. CONCLUSIONS: Participants preferred nonprescription and nonopioid pain relief options. As expected pain levels increased, more participants expressed willingness to accept opioids, but more also mentioned rescue analgesia as a third outcome critical to decision-making. Online deliberative method provided opportunities for obtaining informed perspectives. Guideline developers and policymakers may find online deliberations useful for eliciting PVP related to health outcomes. KNOWLEDGE TRANSFER STATEMENT: Study results informed the US Food and Drug Administration-funded clinical practice guideline on the management of acute dental pain. Findings may be a resource for clinicians in decision-making conversations with patients regarding expectations for pain relief and positive and negative outcomes of differing pain relief medications. Further research should pursue applicability of online deliberative engagement as a method to elicit patient values and preferences.


Subject(s)
Acute Pain , Adult , Humans , Acute Pain/diagnosis , Acute Pain/drug therapy , Pain Management , Analgesics/therapeutic use , Analgesics, Opioid/adverse effects , Patients
2.
J Extracell Vesicles ; 12(11): e12366, 2023 11.
Article in English | MEDLINE | ID: mdl-37885043

ABSTRACT

Extracellular vesicle (EV)-carried miRNAs can influence gene expression and functional phenotypes in recipient cells. Argonaute 2 (Ago2) is a key miRNA-binding protein that has been identified in EVs and could influence RNA silencing. However, Ago2 is in a non-vesicular form in serum and can be an EV contaminant. In addition, RNA-binding proteins (RBPs), including Ago2, and RNAs are often minor EV components whose sorting into EVs may be regulated by cell signaling state. To determine the conditions that influence detection of RBPs and RNAs in EVs, we evaluated the effect of growth factors, oncogene signaling, serum, and cell density on the vesicular and nonvesicular content of Ago2, other RBPs, and RNA in small EV (SEV) preparations. Media components affected both the intravesicular and extravesicular levels of RBPs and miRNAs in EVs, with serum contributing strongly to extravesicular miRNA contamination. Furthermore, isolation of EVs from hollow fiber bioreactors revealed complex preparations, with multiple EV-containing peaks and a large amount of extravesicular Ago2/RBPs. Finally, KRAS mutation impacts the detection of intra- and extra-vesicular Ago2. These data indicate that multiple cell culture conditions and cell states impact the presence of RBPs in EV preparations, some of which can be attributed to serum contamination.


Subject(s)
Argonaute Proteins , Extracellular Vesicles , MicroRNAs , Extracellular Vesicles/metabolism , MicroRNAs/metabolism , Argonaute Proteins/metabolism
3.
Adv Biol Regul ; 90: 100990, 2023 12.
Article in English | MEDLINE | ID: mdl-37801910

ABSTRACT

Gle1 regulates gene expression at multiple steps from transcription to mRNA export to translation under stressed and non-stressed conditions. To better understand Gle1 function in stressed human cells, specific antibodies were generated that recognized the phosphorylation of threonine residue 102 (T102) in Gle1. A series of in vitro kinase assays indicated that T102 phosphorylation serves as a priming event for further phosphorylation in Gle1's N-terminal low complexity cluster. Indirect immunofluorescence microscopy with the anti-Gle1-pT102 antibodies revealed that basally phosphorylated Gle1 was pre-dominantly nuclear with punctate distribution; however, under sodium arsenite-induced stress, more cytoplasmic localization was detected. Immunoprecipitation with the anti-Gle1-pT102 antibody resulted in co-isolation of Gle1-pT102 with the DEAD-box protein DDX1 in a phosphatase sensitive manner. This suggested Gle1 phosphorylation might be linked to its role in regulating DDX1 during transcription termination. Notably, whereas the total Gle1-DDX1 association was decreased when Gle1 nucleocytoplasmic shuttling was disrupted, co-isolation of Gle1-pT102 and DDX1 increased under the same conditions. Taken together, these studies demonstrated that Gle1 phosphorylation impacts its cellular distribution and potentially drives nuclear Gle1 functions in transcription termination. We propose a model wherein phosphorylation of Gle1 either reduces its nucleocytoplasmic shuttling capacity or increases its binding affinity with nuclear interaction partners.


Subject(s)
Nuclear Pore Complex Proteins , Humans , DEAD-box RNA Helicases/genetics , DEAD-box RNA Helicases/metabolism , Nuclear Pore Complex Proteins/chemistry , Nuclear Pore Complex Proteins/genetics , Nuclear Pore Complex Proteins/metabolism , Nucleocytoplasmic Transport Proteins/genetics , Nucleocytoplasmic Transport Proteins/metabolism , Phosphorylation , Cell Nucleus/metabolism
4.
bioRxiv ; 2023 Jul 19.
Article in English | MEDLINE | ID: mdl-37502906

ABSTRACT

Extracellular vesicles (EVs) influence cell phenotypes and functions via protein, nucleic acid and lipid cargoes. EVs are heterogeneous, due to diverse biogenesis mechanisms that remain poorly understood. Our previous study revealed that the endoplasmic reticulum (ER) membrane contact site (MCS) linker protein VAP-A drives biogenesis of a subset of RNA-enriched EVs. Here, we examine the protein content of VAP-A-regulated EVs. Using label-free proteomics, we identified down- and up-regulated proteins in sEVs purified from VAP-A knockdown (KD) colon cancer cells. Gene set enrichment analysis (GSEA) of the data revealed protein classes that are differentially sorted to SEVs dependent on VAP-A. STRING protein-protein interaction network analysis of the RNA-binding protein (RBP) gene set identified several RNA functional machineries that are downregulated in VAP-A KD EVs, including ribosome, spliceosome, mRNA surveillance, and RNA transport proteins. We also observed downregulation of other functionally interacting protein networks, including cadherin-binding, unfolded protein binding, and ATP-dependent proteins.

5.
Cancers (Basel) ; 15(13)2023 Jun 30.
Article in English | MEDLINE | ID: mdl-37444556

ABSTRACT

MOTIVATION: Extracellular vesicles (EVs) are produced and released by most cells and are now recognized to play a role in intercellular communication through the delivery of molecular cargo, including proteins, lipids, and RNA. Small RNA sequencing (small RNA-seq) has been widely used to characterize the small RNA content in EVs. However, there is a lack of a systematic assessment of the quality, technical biases, RNA composition, and RNA biotypes enrichment for small RNA profiling of EVs across cell types, biofluids, and conditions. METHODS: We collected and reanalyzed small RNA-seq datasets for 2756 samples from 83 studies involving 55 with EVs only and 28 with both EVs and matched donor cells. We assessed their quality by the total number of reads after adapter trimming, the overall alignment rate to the host and non-host genomes, and the proportional abundance of total small RNA and specific biotypes, such as miRNA, tRNA, rRNA, and Y RNA. RESULTS: We found that EV extraction methods varied in their reproducibility in isolating small RNAs, with effects on small RNA composition. Comparing proportional abundances of RNA biotypes between EVs and matched donor cells, we discovered that rRNA and tRNA fragments were relatively enriched, but miRNAs and snoRNA were depleted in EVs. Except for the export of eight miRNAs being context-independent, the selective release of most miRNAs into EVs was study-specific. CONCLUSION: This work guides quality control and the selection of EV isolation methods and enhances the interpretation of small RNA contents and preferential loading in EVs.

6.
Nat Rev Mol Cell Biol ; 24(7): 454-476, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36765164

ABSTRACT

To coordinate, adapt and respond to biological signals, cells convey specific messages to other cells. An important aspect of cell-cell communication involves secretion of molecules into the extracellular space. How these molecules are selected for secretion has been a fundamental question in the membrane trafficking field for decades. Recently, extracellular vesicles (EVs) have been recognized as key players in intercellular communication, carrying not only membrane proteins and lipids but also RNAs, cytosolic proteins and other signalling molecules to recipient cells. To communicate the right message, it is essential to sort cargoes into EVs in a regulated and context-specific manner. In recent years, a wealth of lipidomic, proteomic and RNA sequencing studies have revealed that EV cargo composition differs depending upon the donor cell type, metabolic cues and disease states. Analyses of distinct cargo 'fingerprints' have uncovered mechanistic linkages between the activation of specific molecular pathways and cargo sorting. In addition, cell biology studies are beginning to reveal novel biogenesis mechanisms regulated by cellular context. Here, we review context-specific mechanisms of EV biogenesis and cargo sorting, focusing on how cell signalling and cell state influence which cellular components are ultimately targeted to EVs.


Subject(s)
Extracellular Vesicles , Proteomics , Biological Transport , Extracellular Vesicles/metabolism , Protein Transport , Signal Transduction , Cell Communication
7.
Behav Res Methods ; 2022 Sep 09.
Article in English | MEDLINE | ID: mdl-36085543

ABSTRACT

Assessing gaze behavior during real-world tasks is difficult; dynamic bodies moving through dynamic worlds make gaze analysis difficult. Current approaches involve laborious coding of pupil positions. In settings where motion capture and mobile eye tracking are used concurrently in naturalistic tasks, it is critical that data collection be simple, efficient, and systematic. One solution is to combine eye tracking with motion capture to generate 3D gaze vectors. When combined with tracked or known object locations, 3D gaze vector generation can be automated. Here we use combined eye and motion capture and explore how linear regression models generate accurate 3D gaze vectors. We compare spatial accuracy of models derived from four short calibration routines across three pupil data inputs: the efficacy of calibration routines was assessed, a validation task requiring short fixations on task-relevant locations, and a naturalistic object interaction task to bridge the gap between laboratory and "in the wild" studies. Further, we generated and compared models using spherical and Cartesian coordinate systems and monocular (left or right) or binocular data. All calibration routines performed similarly, with the best performance (i.e., sub-centimeter errors) coming from the naturalistic task trials when the participant is looking at an object in front of them. We found that spherical coordinate systems generate the most accurate gaze vectors with no differences in accuracy when using monocular or binocular data. Overall, we recommend 1-min calibration routines using binocular pupil data combined with a spherical world coordinate system to produce the highest-quality gaze vectors.

8.
Oecologia ; 198(3): 645-661, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35279723

ABSTRACT

Epiphyte communities comprise important components of many forest ecosystems in terms of biomass and diversity, but little is known regarding trade-offs that underlie diversity and structure in these communities or the impact that microclimate has on epiphyte trait allocation. We measured 22 functional traits in vascular epiphyte communities across six sites that span a microclimatic gradient in a tropical montane cloud forest region in Costa Rica. We quantified traits that relate to carbon and nitrogen allocation, gas exchange, water storage, and drought tolerance. Functional diversity was high in all but the lowest elevation site where drought likely limits the success of certain species with particular trait combinations. For most traits, variation was explained by relationships with other traits, rather than differences in microclimate across sites. Although there were significant differences in microclimate, epiphyte abundance, and diversity, we found substantial overlap in multivariate trait space across five of the sites. We found significant correlations between functional traits, many of which related to water storage (leaf water content, leaf thickness, hydrenchymal thickness), drought tolerance (turgor loss point), and carbon allocation (specific leaf area, leaf dry matter content). This suite of trait correlations suggests that the epiphyte community has evolved functional strategies along with a drought avoidance versus drought tolerance continuum where leaf succulence emerged as a pivotal overall trait.


Subject(s)
Droughts , Tropical Climate , Ecosystem , Forests , Plant Leaves
9.
Article in English | MEDLINE | ID: mdl-37008559

ABSTRACT

The mechanisms by which cytoplasmic cargoes such as RNAs are incorporated into extracellular vesicles (EVs) are poorly understood. In a recent article published in Developmental Cell, we describe a novel function of endoplasmic reticulum membrane contact sites (ER MCS) in regulating biogenesis of RNA-containing EVs (Barman et al., 2022). We identified the ER MCS tether protein VAP-A and the ceramide transporter CERT as key drivers of this process. VAP-A depletion and overexpression produced corresponding changes in the overall number and RNA content of secreted EVs. Further sub-fractionation of small EVs from VAP-A depleted cells revealed a distinct loss in a specific subset of dense, RNA-loaded small EVs that are critical for the transfer of miR-100 to recipient cells. Cell imaging data confirmed the loss of RNA and RNA binding proteins (RBPs) in VAP-A-knockdown multivesicular bodies. Lipid analysis of VAP-A-knockdown EVs revealed decreases in ceramides, which are known to affect EV biogenesis. Depletion of the ceramide transfer protein CERT, which interacts with its binding partner VAP-A at ER MCS, leads to similar defects in EV number and RNA content as VAP-A-knockdown. These data suggest a model for ER MCS as platforms for biogenesis of a key EV population via ceramide transfer and RNA loading.

10.
Sci Rep ; 9(1): 12049, 2019 Aug 19.
Article in English | MEDLINE | ID: mdl-31427739

ABSTRACT

Intense femtosecond pulse filamentation in open-air has been utilized for long distance optical communication and remote sensing, but it results in nonlinear-effect driven eye hazards which are not addressed by current eye safety standards. A systematic study of filamentation in atmospheric air was performed using a tunable 100 fs near-infrared laser (1100 nm-2400 nm). While undergoing filamentation, each source wavelength was spectrally broadened resulting in supercontinuum and third harmonic generation in the visible and near-IR spectrum. We record the spectra at the center and fringes of the supercontinuum as it is imaged onto a planar surface. In a full beam collection regime, we report the energy of the sub-1000 nm light generation for source wavelengths from 1100 nm to 1600 nm and compare the energy density to the maximum permissible exposure values under the ANSI Z136.1 laser safety standard.

11.
Br J Dermatol ; 181(4): 691-699, 2019 10.
Article in English | MEDLINE | ID: mdl-31342510

ABSTRACT

BACKGROUND: The role of skin microbiota in acne remains to be fully elucidated. Initial culture-based investigations were hampered by growth rate and selective media bias. Even with less biased genomic methods, sampling, lysis and methodology, the task of describing acne pathophysiology remains challenging. Acne occurs in sites dominated by Cutibacterium acnes (formerly Propionibacterium acnes) and Malassezia species, both of which can function either as commensal or pathogen. OBJECTIVES: This article aims to review the current state of the art of the microbiome and acne. METHODS: The literature regarding the microbiome and acne was reviewed. RESULTS: It remains unclear whether there is a quantitative difference in microbial community distribution, making it challenging to understand any community shift from commensal to pathogenic nature. It is plausible that acne involves (i) change in the distribution of species/strains, (ii) stable distribution with pathogenic alteration in response to internal (intermicrobe) or external stimuli (host physiology or environmental) or (iii) a combination of these factors. CONCLUSIONS: Understanding physiological changes in bacterial species and strains will be required to define their specific roles, and identify any potential intervention points, in acne pathogenesis and treatment. It will also be necessary to determine whether any fungal species are involved, and establish whether they play a significant role. Further investigation using robust, modern analytic tools in longitudinal studies with a large number of participants, may make it possible to determine whether the microbiota plays a causal role, is primarily involved in exacerbation, or is merely a bystander. It is likely that the final outcome will show that acne is the result of complex microbe-microbe and community-host interplay.


Subject(s)
Acne Vulgaris/etiology , Malassezia/immunology , Microbiota/immunology , Propionibacterium acnes/immunology , Skin/microbiology , Humans , Malassezia/pathogenicity , Propionibacterium acnes/pathogenicity , Skin/immunology , Symbiosis/immunology
12.
Opt Express ; 27(3): 2828-2836, 2019 Feb 04.
Article in English | MEDLINE | ID: mdl-30732314

ABSTRACT

Polycrystalline zinc selenide (ZnSe) has been the subject of many nonlinear optics studies for wavelengths under 4.0 µm including sum/difference frequency generation, harmonic generation, and filamentation. In this report, the conversion efficiency of high harmonic generation (HHG) in ZnSe is quantified for mid-infrared wavelengths ranging from 2.7 µm to 8.0 µm. By increasing the fundamental wavelength, we demonstrate that HHG in thick ZnSe targets is limited by the band gap. The high conversion efficiency of mid-infrared to near-infrared light in ZnSe raises concerns of a nonlinear retinal hazard. We contrast the HHG behavior of ZnSe against the observed harmonic generation of calcium fluoride, BK7, and fused silica over the same wavelengths.

13.
J Biol Chem ; 294(2): 559-575, 2019 01 11.
Article in English | MEDLINE | ID: mdl-30429220

ABSTRACT

Rapid expression of critical stress response factors is a key survival strategy for diseased or stressed cells. During cell stress, translation is inhibited, and a pre-existing pool of cytoplasmic mRNA-protein complexes reversibly assembles into cytoplasmic stress granules (SGs). Gle1 is a conserved modulator of RNA-dependent DEAD-box proteins required for mRNA export, translation, and stress responses. Proper Gle1 function is critical as reflected by some human diseases such as developmental and neurodegenerative disorders and some cancers linked to gle1 mutations. However, the mechanism by which Gle1 controls SG formation is incompletely understood. Here, we show that human Gle1 is regulated by phosphorylation during heat shock stress. In HeLa cells, stress-induced Gle1 hyperphosphorylation was dynamic, primarily in the cytoplasmic pool, and followed changes in translation factors. MS analysis identified 14 phosphorylation sites in the Gle1A isoform, six of which clustered in an intrinsically disordered, low-complexity N-terminal region flanking the coil-coiled self-association domain. Of note, two mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK), phosphorylated the Gle1A N-terminal domain, priming it for phosphorylation by glycogen synthase kinase 3 (GSK3). A phosphomimetic gle1A6D variant (in which six putative Ser/Thr phosphorylation sites were substituted with Asp) perturbed self-association and inhibited DEAD-box helicase 3 (X-linked) (DDX3) ATPase activity. Expression of alanine-substituted, phosphodeficient GFP-gle1A6A promoted SG assembly, whereas GFP-gle1A6D enhanced SG disassembly. We propose that MAPKs and GSK3 phosphorylate Gle1A and thereby coordinate SG dynamics by altering DDX3 function.


Subject(s)
DEAD-box RNA Helicases/metabolism , Glycogen Synthase Kinase 3/metabolism , Mitogen-Activated Protein Kinases/metabolism , Nucleocytoplasmic Transport Proteins/metabolism , Adenosine Triphosphatases/metabolism , Cytoplasmic Granules/metabolism , HeLa Cells , Humans , Phosphorylation , RNA, Messenger/metabolism
14.
Opt Lett ; 43(17): 4196-4199, 2018 Sep 01.
Article in English | MEDLINE | ID: mdl-30160750

ABSTRACT

Understanding the nonlinear properties of water is essential for laser surgery applications, as well as understanding supercontinuum generation in water. Unfortunately, the nonlinear properties of water for wavelengths longer than 1064 nm are poorly understood. We extend the application of the Z-scan technique in water to determine its nonlinear refractive index (n2) and nonlinear absorption (ß) for wavelengths in the 1150-1400 nm range, where linear absorption is also significant. We observe the wavelength-dependent variation of the nonlinear properties of water around the water absorption band.

15.
Neuropathol Appl Neurobiol ; 44(7): 663-672, 2018 12.
Article in English | MEDLINE | ID: mdl-29533475

ABSTRACT

AIMS: To develop an expert consensus statement regarding appropriate clinical and forensic post mortem neurological imaging. METHODS: An expert panel of clinicians were recruited from registered members of the British Neuropathological Society (BNS) and the International Society of Forensic Radiology and Imaging (ISFRI) with post mortem expertise. Following a focus group meeting, 16 core statements were incorporated into an online modified Delphi survey and each panellist was asked to score their level of agreement. Following the first iteration, two statements that failed to reach consensus were modified and re-rated. Consensus was predefined as 75% agreement across responders. RESULTS: Seventeen experts joined the panel and 12 (70.6%) attended the focus group meeting; 14 (82%) completed both iterations of the survey. Consensus was reached for need of adequate clinical history, multidisciplinary discussion, establishment of special interest groups to discuss cases, gathering further evidence to inform imaging choices, establishment of methods for quality assessment in reporting standards and adequate funding for imaging services. The panel agreed that pathologists should be responsible for neuroimaging referrals, collating results of ancillary tests, and producing the final post mortem report. Areas requiring further discussion include the impact of double reporting, indications for neuroimaging and utilities of three-dimensional printing. CONCLUSION: The BNS/ISFRI statement represents current views of an expert panel of health professionals engaged in post-mortem neuroimaging. We hope this provides a working guideline for less experienced operators, stimulates discussion and highlights the most pressing clinical and research questions.


Subject(s)
Autopsy/methods , Brain/diagnostic imaging , Neuroimaging , Brain/pathology , Consensus , Humans , Magnetic Resonance Imaging , Tomography, X-Ray Computed
16.
Dev Cell ; 43(2): 115-117, 2017 10 23.
Article in English | MEDLINE | ID: mdl-29065301

ABSTRACT

Reporting in this issue of Developmental Cell, Linder et al. (2017) and Martino et al. (2017) reveal in highly complementary studies that Plk1 is recruited to the nuclear pore complex upon mitotic entry, where it acts with Cdk1 to hyperphosphorylate nucleoporin interfaces to promote NPC disassembly and nuclear envelope breakdown.


Subject(s)
Nuclear Pore Complex Proteins , Nuclear Pore , Mitosis , Nuclear Envelope , Phosphorylation
17.
Sci Rep ; 7: 44572, 2017 03 15.
Article in English | MEDLINE | ID: mdl-28294165

ABSTRACT

Optical imaging of fast events and processes is essential for understanding dynamics of complex systems. A bright flash of illuminating light is required to acquire sufficient number of photons for superior image quality. Laser pulses can provide extreme brightness and are typically employed to achieve high temporal resolution; however, the high degree of coherence associated with the lasing process degrades the image quality with speckle formation. Random lasers are low-coherence sources of stimulated emission and do not suffer from speckle, but are rather broadband and have a relatively low output power limiting the scope of their potential applications. In this report, we demonstrate the use of random Raman lasing as a novel imaging light source with unprecedented brightness for a speckle-free and narrowband light source. We showcase the advantages of a random Raman laser to image the nanosecond scale dynamics of cavitation formation in water and quantitatively compare these images to those taken with incoherent fluorescent emission and coherent laser light as illumination source.

18.
Analyst ; 142(7): 1054-1060, 2017 Apr 07.
Article in English | MEDLINE | ID: mdl-28294227

ABSTRACT

Lipids produced by microalgae are viewed as a potential renewable alternative to fossil fuels, however, significant improvements in productivity are required for microalgal biofuels to become economically feasible. Here we present a method that allows for the use of Raman spectroscopy with poly(dimethylsiloxane) (PDMS) droplet microfluidic devices, which not only overcomes the high Raman background of PDMS, but also achieves pairing of the high-throughput single-cell resolution advantages of droplet microfluidics with the direct, chemically specific, label-free, and non-destructive nature of Raman spectroscopy. The platform was successfully utilized for in situ characterization of microalgal lipid production over time within droplets, paving the way towards high-throughput microalgal lipidomics assays.


Subject(s)
Biofuels , Lipids/analysis , Microalgae/chemistry , Microfluidic Analytical Techniques/instrumentation , Spectrum Analysis, Raman , Chlamydomonas reinhardtii/chemistry , Lipids/biosynthesis
20.
Org Biomol Chem ; 14(24): 5714-20, 2016 Jun 28.
Article in English | MEDLINE | ID: mdl-26880344

ABSTRACT

Reversible template-directed micellar-size and shape modulation by virtue of host-guest reversible docking of molecular templates at the micellar-solvent interface was achieved in water. By combining a π-electron deficient bipyridinium-based gemini amphiphile which is capable of binding and aligning with a π-electron rich tri(ethylene glycol)-disubstituted 1,5-diaminonaphthalene, a switchable detergent system which operates through the pH-responsive formation of bisammonium dications was realised. The binding of the 1,5-diaminonaphthalene guest to the bipyridinium-based micellar aggregate superstructure can be actuated by the addition of acid and base. Upon the addition of acid, protonation of the guest forming the dication deactivates molecular recognition with the charged head groups of the micellar aggregate by Coulombic repulsion. This process is completely reversible upon the addition of base, whereby the guest reintercalates into the superstructure -again forming donor-acceptor π-π stacks at the micellar-solvent interface amongst contiguous surfactant head groups. Synchrotron small angle X-ray scattering and dynamic laser light scattering confirm that this form of reversible directionally-templated micellisation results in an oblate spheroid-to-lamellar micelle morphological transition with a stabilising net decrease in the free energy of micellisation of 1.4 kcal mol(-1) per hydrophobic tail.

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