1
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Heaton AR, Lechuga LM, Tangsangasaksri M, Ludwig KD, Fain SB, Mecozzi S. A stable, highly concentrated fluorous nanoemulsion formulation for in vivo cancer imaging via 19F-MRI. NMR Biomed 2024; 37:e5100. [PMID: 38230415 PMCID: PMC10987282 DOI: 10.1002/nbm.5100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 12/06/2023] [Accepted: 12/07/2023] [Indexed: 01/18/2024]
Abstract
Magnetic resonance imaging (MRI) is a routine diagnostic modality in oncology that produces excellent imaging resolution and tumor contrast without the use of ionizing radiation. However, improved contrast agents are still needed to further increase detection sensitivity and avoid toxicity/allergic reactions associated with paramagnetic metal contrast agents, which may be seen in a small percentage of the human population. Fluorine-19 (19F)-MRI is at the forefront of the developing MRI methodologies due to near-zero background signal, high natural abundance of 100%, and unambiguous signal specificity. In this study, we have developed a colloidal nanoemulsion (NE) formulation that can encapsulate high volumes of the fluorous MRI tracer, perfluoro-[15-crown-5]-ether (PFCE) (35% v/v). These nanoparticles exhibit long-term (at least 100 days) stability and high PFCE loading capacity in formulation with our semifluorinated triblock copolymer, M2F8H18. With sizes of approximately 200 nm, these NEs enable in vivo delivery and passive targeting to tumors. Our diagnostic formulation, M2F8H18/PFCE NE, yielded in vivo 19F-MR images with a high signal-to-noise ratio up to 100 in a tumor-bearing mouse model at clinically relevant scan times. M2F8H18/PFCE NE circulated stably in the vasculature, accumulated in high concentration of an estimated 4-9 × 1017 19F spins/voxel at the tumor site, and cleared from most organs over the span of 2 weeks. Uptake by the mononuclear phagocyte system to the liver and spleen was also observed, most likely due to particle size. These promising results suggest that M2F8H18/PFCE NE is a favorable 19F-MR diagnostic tracer for further development in oncological studies and potential clinical translation.
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Affiliation(s)
- Alexa R. Heaton
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave Madison WI 53706, USA
| | - Lawrence M. Lechuga
- Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Ave Madison WI 53705, USA
| | | | - Kai D. Ludwig
- Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Ave Madison WI 53705, USA
| | - Sean B. Fain
- Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Ave Madison WI 53705, USA
- Department of Radiology, University of Iowa, 200 Hawkins Drive Iowa City IA 52242, USA
| | - Sandro Mecozzi
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave Madison WI 53706, USA
- School of Pharmacy, University of Wisconsin-Madison, 777 Highland Ave Madison WI 53705, USA
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2
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Padilla MS, Tangsangasaksri M, Chang CC, Mecozzi S. MCT Nanoemulsions for the Efficient Delivery of siRNA. J Pharm Sci 2024; 113:764-771. [PMID: 37984699 DOI: 10.1016/j.xphs.2023.11.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 11/14/2023] [Accepted: 11/14/2023] [Indexed: 11/22/2023]
Abstract
In this study, an oil-in-water (o/w) nanoemulsion is used to deliver siRNA targeting Twist1, a protein that contributes to tumor metastasis in a variety of cancers. The FDA-approved oil, medium chain triglycerides (MCT), is used as the hydrophobic phase for the nanoemulsion. The siRNA is paired with dioleoyl-3-trimethylammonium-propane (DOTAP) to form a hydrophobic salt that is soluble at high concentrations in MCT. The resulting MCT/siRNA-DOTAP solution is formulated into a nanoemulsion with an average particle size of 140 nm. The nanoemulsion displays long term stability over the course of 195 days. In an in vivo murine tumor model, the nanoemulsion facilitates a 46% decrease in Twist1 mRNA after 48 h.
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Affiliation(s)
- Marshall S Padilla
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, United States of America
| | - Montira Tangsangasaksri
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, United States of America
| | - Chih-Chun Chang
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, United States of America
| | - Sandro Mecozzi
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, United States of America.
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3
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Wang J, Drelich AJ, Hopkins CM, Mecozzi S, Li L, Kwon G, Hong S. Gold nanoparticles in virus detection: Recent advances and potential considerations for SARS-CoV-2 testing development. Wiley Interdiscip Rev Nanomed Nanobiotechnol 2021; 14:e1754. [PMID: 34498423 PMCID: PMC8646453 DOI: 10.1002/wnan.1754] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 08/05/2021] [Accepted: 08/11/2021] [Indexed: 12/24/2022]
Abstract
Viruses are infectious agents that pose significant threats to plants, animals, and humans. The current coronavirus disease 2019 pandemic, which is caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), has spread globally and resulted in over 2 million deaths and immeasurable financial losses. Rapid and sensitive virus diagnostics become crucially important in controlling the spread of a pandemic before effective treatment and vaccines are available. Gold nanoparticle (AuNP)‐based testing holds great potential for this urgent unmet biomedical need. In this review, we describe the most recent advances in AuNP‐based viral detection applications. In addition, we discuss considerations for the design of AuNP‐based SARS‐CoV‐2 testings. Finally, we highlight and propose important parameters to consider for the future development of effective AuNP‐based testings that would be critical for not only this COVID‐19 pandemic, but also potential future outbreaks. This article is categorized under:Diagnostic Tools > Biosensing Diagnostic Tools > In Vitro Nanoparticle‐Based Sensing
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Affiliation(s)
- Jianxin Wang
- Wisconsin Center for NanoBioSystems, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Adam J Drelich
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Caroline M Hopkins
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Sandro Mecozzi
- Wisconsin Center for NanoBioSystems, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Lingjun Li
- Wisconsin Center for NanoBioSystems, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Glen Kwon
- Wisconsin Center for NanoBioSystems, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Seungpyo Hong
- Wisconsin Center for NanoBioSystems, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Yonsei Frontier Lab and Department of Pharmacy, Yonsei University, Seoul, Republic of Korea
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4
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Esson MM, Mecozzi S. Preparation, Characterization, and Formulation Optimization of Ionic-Liquid-in-Water Nanoemulsions toward Systemic Delivery of Amphotericin B. Mol Pharm 2020; 17:2221-2226. [PMID: 32343901 DOI: 10.1021/acs.molpharmaceut.9b00809] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Amphotericin B (AmB) is an antifungal agent that poses a challenge for intravenous drug delivery due to its hydrophobicity and severe side effects that are attributed to the self-aggregation of AmB in aqueous solution. To overcome this problem, we have rationally designed an ionic-liquid-in-water nanoemulsion drug delivery system that harnesses the unique properties of ionic liquids. The complex drug AmB serves as a model pharmaceutical agent to demonstrate the robustness of ionic-liquid-in-water nanoemulsions. High concentrations of AmB were solubilized in a new hydrophobic dicholinium-based ionic liquid. The absorption spectrum of AmB in an ionic liquid mixture and prepared nanoemulsion indicates AmB solubilization in the monomeric form. The hydrophobic ionic liquid exhibits high in vivo biocompatibility with zebrafish. The hemolytic activity of the AmB nanoemulsion was negligible, yet it maintained antifungal activity against Candida albicans. The preliminary results presented in this Communication indicate that ionic-liquid-in-water nanoemulsions may allow for the delivery of a variety of pharmaceuticals intravenously, broadening the scope of ionic liquids in the pharmaceutical sciences.
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Affiliation(s)
- Moira M Esson
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Sandro Mecozzi
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States.,School of Pharmacy, University of Wisconsin-Madison, 777 Highland Avenue, Madison, Wisconsin 53705, United States
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5
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Barres AR, Molugu SK, Stewart PL, Mecozzi S. Droplet Core Intermolecular Interactions and Block Copolymer Composition Heavily Influence Oil-In-Water Nanoemulsion Stability. Langmuir 2019; 35:12765-12772. [PMID: 31532686 PMCID: PMC7454039 DOI: 10.1021/acs.langmuir.9b01519] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Colloidal oil-in-water nanoemulsions are gaining increasing interest as a nanoparticle delivery system because of their large oil droplet core that can carry a large payload. In order to formulate these particles with long-term stability, an appropriate oil media and block copolymer pair must be selected. The interaction between the nanoemulsion core and the polymer shell is critical to forming stable nanoparticles. Herein, we probed how interactions between various polymers with hydrocarbon and perfluorocarbon oil media influenced nanoemulsion formation, stability, and size. Through a series of nanoemulsions with unique polymer/oil media combinations, we examined the effects of oil core hydrophobicity, fluorophilicity, surface charge, and volume as well as the effects of polymer tail composition. Surprisingly, we found that nanoemulsions formulated with pure perfluorocarbon oil cores versus perfluoro poly(ether) oil cores exhibited very different characteristics. We also found that both hydrocarbon and fluorocarbon polymer tails interacted favorably with perfluoro poly(ethers) as well as hydrocarbon oil cores forming stable nanoemulsions. We believe these results are focused on the unique properties of perfluorocarbons especially their rigidity, low polarizability, and near-zero surface charge. Interestingly, we saw that perfluoro poly(ethers) deviated from these expected properties resulting in an increased versatility when formulating nanoemulsions with perfluoro poly(ether) oil cores compared to pure perfluorocarbon oil cores. Nanoemulsion size, stability, growth rate, and life time were explored to probe these factors. Experimental and computational data are presented as a rationale.
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Affiliation(s)
- Alexa R. Barres
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave Madison WI 53706, USA
| | - Sudheer K. Molugu
- School of Medicine, Department of Pharmacology and Cleveland Center for Membrane and Structural Biology, Case Western Reserve University, 10900 Euclid Ave Cleveland OH 44106, USA
| | - Phoebe L. Stewart
- School of Medicine, Department of Pharmacology and Cleveland Center for Membrane and Structural Biology, Case Western Reserve University, 10900 Euclid Ave Cleveland OH 44106, USA
| | - Sandro Mecozzi
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave Madison WI 53706, USA
- School of Pharmacy, University of Wisconsin-Madison, 777 Highland Ave Madison WI 53705, USA
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6
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Abstract
The presence of a perfluorocarbon block in a multiblock polymer has been shown to be an additional driving force toward nanoparticle assembly. In the preparation of nanoemulsions, this perfluorocarbon block also provides enhanced particle stability. Herein, the synthesis of a new triphilic, semifluorinated copolymer, M2F8H18, is introduced. This ABC type block copolymer can be used to formulate extremely stable nanoemulsions, assembled around a lipophilic droplet, with lifetimes of one year or more. The central oil droplet can stably solubilize high concentrations of hydrophobic drugs, making this system an ideal drug delivery vehicle. The incorporation of the perfluorocarbon block modulates drug release from the lipophilic core via the surrounding fluorous shell. Fluorous imaging agents incorporated into the fluorous shell prolong drug release even further as well as provide potent 19F-MRI contrast ability. In vitro studies show that these nanoemulsions efficiently inhibit cancer cell growth, thus providing a theranostic drug delivery system.
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Affiliation(s)
- Alexa R Barres
- Department of Chemistry and ‡School of Pharmacy, University of Wisconsin-Madison , Madison, Wisconsin 53705, United States
| | - Megan R Wimmer
- Department of Chemistry and ‡School of Pharmacy, University of Wisconsin-Madison , Madison, Wisconsin 53705, United States
| | - Sandro Mecozzi
- Department of Chemistry and ‡School of Pharmacy, University of Wisconsin-Madison , Madison, Wisconsin 53705, United States
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7
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Fleetwood MC, McCoy AM, Mecozzi S. Synthesis and characterization of environmentally benign, semifluorinated polymers and their applications in drug delivery. J Fluor Chem 2016. [DOI: 10.1016/j.jfluchem.2016.09.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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8
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Razgulin AV, Mecozzi S. Synthesis, emulsification and self-assembly properties of sugar-containing semifluorinated amphiphiles. Carbohydr Res 2015; 406:10-8. [PMID: 25658061 DOI: 10.1016/j.carres.2014.12.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 12/20/2014] [Accepted: 12/22/2014] [Indexed: 11/16/2022]
Abstract
Surfactants with two and three monosaccharide-based heads and a perfluoroalkyl tail have been synthesized. Perfluoroalkyl C3-symmetric triol and C2-symmetric diol were conveniently prepared via Cu-catalyzed azide-alkyne cycloaddition between a fluorous alkyne and tertiary and secondary azides, respectively. Glycosylation of the perfluoroalkyl diol and triol led to orthoester-type structures, which were evaluated for their capacity to stabilize aqueous emulsions of highly fluorinated anesthetics. The self-assembly properties of the tri-sugar amphiphile were examined by transmission electron microscopy.
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Affiliation(s)
- Andrew V Razgulin
- Department of Chemistry, University of Wisconsin, 777 Highland Avenue, Madison, WI 53705, USA
| | - Sandro Mecozzi
- Department of Chemistry, University of Wisconsin, 777 Highland Avenue, Madison, WI 53705, USA; School of Pharmacy, University of Wisconsin, 777 Highland Avenue, Madison, WI 53705, USA.
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9
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Tucker W, McCoy AM, Fix S, Stagg M, Murphy M, Mecozzi S. Synthesis, physicochemical characterization, and self-assembly of linear, dibranched, and miktoarm semifluorinated triphilic polymers. J Polym Sci A Polym Chem 2014; 52:3324-3336. [PMID: 31223200 PMCID: PMC6586239 DOI: 10.1002/pola.27394] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Linear, dibranched and miktoarm amphiphiles containing both hydrophobic and fluorophilic moieties were synthesized and characterized in an attempt to elucidate the relationship between semi-fluorinated amphiphile structure and aggregate behaviour in aqueous solution. For the linear and dibranched amphiphiles, there was an exponential decrease in critical aggregation concentration (CMC) and a logarithmic increase in core microviscosity with increasing length of the fluorocarbon segments; while the miktoarm architecture produced no notable trend in microviscosity or CMC. Furthermore, the linear and dibranched surfactants showed enhanced kinetic stability, dissociating more slowly in the presence of human serum than did either the dibranched or miktoarm amphiphiles. Finally, encapsulation studies with the hydrophobic drug paclitaxel (PTX) showed that the ability to solubilize and retain PTX increased with the presence and with the increasing size of the fluorocarbon moiety for both the linear and dibranched amphiphiles, while no such trend was observed for the miktoarm amphiphiles.
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Affiliation(s)
- W.B. Tucker
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706
| | - A. M. McCoy
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706
| | - S.M. Fix
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706
| | - M.F. Stagg
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706
| | - M.M. Murphy
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706
| | - S. Mecozzi
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705
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10
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Decato S, Bemis T, Madsen E, Mecozzi S. Synthesis and characterization of perfluoro- tert-butyl semifluorinated amphiphilic polymers and their potential application in hydrophobic drug delivery. Polym Chem 2014; 5:6461-6471. [PMID: 25383100 DOI: 10.1039/c4py00882k] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Semifluorinated polymer surfactants, composed of a monomethyl poly(ethylene glycol) (mPEG) hydrophilic head group and either 1, 2, or 3 perfluoro-tert-butyl (PFtB) groups as the fluorophilic tail, were synthesized, and their aqueous self-assemblies were investigated as a potential design for theranostic nanoparticles. Polymers with three PFtB groups (PFtBTRI) solely formed stable, spherical micelles, approximately 12 nm in size. These PFtBTRI surfactants demonstrate similar characteristics with those of polymers with linear perfluorocarbon tails, despite large differences in tail structure. For example, PFtB polymer solutions stably emulsified 20 v/v% sevoflurane with perfluorooctyl bromide (PFOB) as a stabilizer. However, these PFtB polymers have the additional potential to serve as F-MRI contrast agents. PFtBTRI micelles gave one narrow 19F-NMR signal in D2O, with T1 and T2 parameters of approximately 500 and 100 ms, respectively. 19F-MR images of PFtB polymer solutions at 1 mM gave intense signal at 4.7 T without sensitizers or selective excitation sequences. These preliminary data demonstrate the potential of PFtB polymers as a basic design, which can be further modified to serve as dual drug-delivery and imaging vehicles.
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Affiliation(s)
- Sarah Decato
- Department of Chemistry, University of Wisconsin - Madison, Madison, Wisconsin 53706
| | - Troy Bemis
- Department of Chemistry, University of Wisconsin - Madison, Madison, Wisconsin 53706
| | - Eric Madsen
- Department of Chemistry, University of Wisconsin - Madison, Madison, Wisconsin 53706
| | - Sandro Mecozzi
- School of Pharmacy, University of Wisconsin - Madison, Madison Wisconsin 53705
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11
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Abstract
The stability of fluorotelomer alcohols under basic conditions was studied. HF elimination across the CF2-CH2 junction is shown to be facilitated by an intramolecular hydrogen bond, while solvation is the key determinant in the stability of alcohols of various perfluoroalkyl lengths. Finally, fluorotelomer alcohols can be rendered kinetically stable if either the alcohol or the base has low solubility in the reaction medium.
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Affiliation(s)
- William B Tucker
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin, 53705 USA
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12
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Jee JP, Parlato MC, Perkins MG, Mecozzi S, Pearce RA. Exceptionally stable fluorous emulsions for the intravenous delivery of volatile general anesthetics. Anesthesiology 2012; 116:580-5. [PMID: 22354241 DOI: 10.1097/aln.0b013e3182475d4d] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND IV delivery of volatile fluorinated anesthetics has a number of potential advantages when compared with the current inhalation method of administration. We reported previously that the IV delivery of sevoflurane can be achieved through an emulsion composed of a linear fluorinated diblock copolymer, a stabilizer, and the anesthetic. However, this original emulsion was subject to particle size growth that would limit its potential clinical utility. We hypothesized that the use of bulkier fluorous groups and smaller polyethylene glycol moieties in the polymer design would result in improved emulsion stability while maintaining anesthetic functionality. METHODS The authors prepared emulsions incorporating sevoflurane, perfluorooctyl bromide as a stabilizing agent, and combinations of linear fluorinated diblock copolymer and a novel dibranched fluorinated diblock copolymer. Emulsion stability was assessed using dynamic light scattering. The ability of the emulsions to induce anesthesia was tested in vivo by administering them intravenously to 15 male Sprague-Dawley rats and measuring loss of the forepaw righting reflex. RESULTS 20% (volume/volume) sevoflurane emulsions incorporating mixtures of dibranched and linear diblock copolymers had improved stability, with those containing an excess of the dibranched polymers displaying stability of particle size for more than 1 yr. The ED50s for loss of forepaw-righting reflex were all similar, and ranged between 0.55- 0.60 ml/kg body weight. CONCLUSIONS Hemifluorinated dibranched polymers can be used to generate exceptionally stable sevoflurane nanoemulsions, as required of formulations intended for clinical use. IV delivery of the emulsion in rats resulted in induction of anesthesia with rapid onset and smooth and rapid recovery.
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Affiliation(s)
- Jun-Pil Jee
- School of Pharmacy, Department of Anesthesiology,University of Wisconsin, Madison, Wisconsin 53705, USA
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14
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Simmons K, Nejati E, Johnson R, Pearce R, Albrecht R, Mecozzi S. Investigation of Hypersensitivity to PEGylated Particles For Use in Drug Delivery. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.1120.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ken Simmons
- School of PharmacyUniversity of Wisconsin - MadisonMadisonWI
| | - Elham Nejati
- School of PharmacyUniversity of Wisconsin - MadisonMadisonWI
| | - Rebecca Johnson
- School of Veterinary MedicineUniversity of Wisconsin - MadisonMadisonWI
| | - Robert Pearce
- Department of AnesthesiologyUniversity of Wisconsin - MadisonMadisonWI
| | - Ralph Albrecht
- School of PharmacyUniversity of Wisconsin - MadisonMadisonWI
- Department of Animal SciencesUniversity of Wisconsin - MadisonMadisonWI
| | - Sandro Mecozzi
- School of PharmacyUniversity of Wisconsin - MadisonMadisonWI
- Department of ChemistryUniversity of Wisconsin - MadisonMadisonWI
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Abstract
Here we describe the synthesis and the physicochemical and preliminary pharmaceutical assessment of a novel class of hemifluorinated dibranched derivatives: M(1)diH(x)F(y). These compounds have the remarkable ability to completely stop the Ostwald ripening commonly associated with nanoemulsions. The developed synthesis is modular and allows easy incremental structural variations in the fluorophilic (fluorous chains), lipophilic (alkyl spacer head), and hydrophilic (polar head) domains. Furthermore, the synthesis can be easily scaled up and highly pure compounds can be readily obtained through silica gel and fluoro-silica gel column chromatography, without any need to use HPLC or other time-consuming techniques. Surface properties such as micelle formation, critical aggregation concentration (CAC), and emulsion stability studies demonstrated the different behavior of the dibranched hemifluorinated surfactant M(1)diH(x)F(y) with respect to that of single-chain semifluorinated analogues M(z)F(y). Remarkably, the new polymer M(1)diH(3)F(8) drastically slowed the ripening of nanoemulsions of the commonly used fluorinated anesthetic sevoflurane over a period of more than 1 year. During this time, the nanodroplet size did not increase to more than 400 nm. This result is very promising for inducing and maintaining general anesthesia through intravenous delivery of volatile anesthetics, eliminating the need for the use of large and costly vaporizers in the operating room.
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16
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Jee JP, McCoy A, Mecozzi S. Encapsulation and release of Amphotericin B from an ABC triblock fluorous copolymer. Pharm Res 2011; 29:69-82. [PMID: 21739321 DOI: 10.1007/s11095-011-0511-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Accepted: 06/10/2011] [Indexed: 01/08/2023]
Abstract
PURPOSE PEG-phospholipid-based micelles have been successfully used for the solubilization of several hydrophobic drugs but generally lack sustained stability in blood. Our novel PEG-Fluorocarbon-DSPE polymers were designed to increase stability and improve time-release properties of drug-loaded micelles. METHODS Novel ABC fluorous copolymers were synthesized, characterized, and used for encapsulation release of amphotericin B. FRET studies were used to study micelle stability. RESULTS The micelles formed by the new polymers showed lower critical micelle concentrations and higher viscosity cores than those formed by the polymers lacking the fluorous block. FRET studies indicated that fluorocarbon-containing micelles had increased stability in presence of human serum. Physicochemical properties and in vitro release profile of micelles loaded with Amphotericin B (AmB) were studied. CONCLUSIONS The effect of PEG length and fluorocarbon incorporation were investigated. The shorter hydrophilic PEG2K induced greater stability than PEG5K by decreasing the proportion of hydrophilic block of the polymer. The fluorocarbon placed between hydrophilic and hydrophobic block formed a fluorous shell contributing to the enhanced thermodynamic stability of micelles and to the drug sustained release. Polymer mPEG2K-F(10)-DSPE, bearing both a fluorocarbon block and a shorter mPEG, showed the greatest stability and the longest half-life for AmB release.
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Affiliation(s)
- Jun-Pil Jee
- School of Pharmacy, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA
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17
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Johnson RA, Simmons KT, Fast JP, Schroeder CA, Pearce RA, Albrecht RM, Mecozzi S. Histamine release associated with intravenous delivery of a fluorocarbon-based sevoflurane emulsion in canines. J Pharm Sci 2011; 100:2685-92. [PMID: 21246564 DOI: 10.1002/jps.22488] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 12/29/2010] [Accepted: 12/29/2010] [Indexed: 11/06/2022]
Abstract
The purpose of this study was to evaluate the effectiveness of a novel fluorocarbon-based sevoflurane emulsion in dogs previously shown to produce short-term rodent anesthesia. On the basis of an unexpected allergic-type clinical reaction, we also tested the hypothesis that this type of formulation causes histamine release and complement activation. Physiological parameters, plasma histamine levels (radioimmunoassay), and complement activation (enzyme immunoassay) were quantified in response to emulsion components, including F13M5 (the emulsion's fluorocarbon-based polymer) and methoxy poly(ethylene glycol) 5000 (the polymer's hydrophilic block). Although the emulsion produced general anesthesia in dogs, they also experienced hypotension and clinical signs suggestive of an allergic-like response (i.e., vasodilation, urticaria, and pruritus upon recovery). Emulsions lacking sevoflurane failed to induce anesthesia but did elicit the allergic response. Plasma histamine levels were significantly increased following injection of micellar solutions of F13M5. Direct complement activation by the emulsion or its components was weak or absent. An allergic response leading to histamine release, likely initiated by the F13M5 component via an immunoglobulin pathway, is associated with an intravenous fluorocarbon-based emulsion of sevoflurane. Subsequently, its usefulness in medicine in its present formulation is limited.
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Affiliation(s)
- Rebecca A Johnson
- Department of Surgical Sciences, University of Wisconsin, Madison, Wisconsin 53706, USA.
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Anderson PC, Mecozzi S. Minimum sequence requirements for selective RNA-ligand binding: a molecular mechanics algorithm using molecular dynamics and free-energy techniques. J Comput Chem 2007; 27:1631-40. [PMID: 16900493 DOI: 10.1002/jcc.20459] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In vitro evolution techniques allow RNA molecules with unique functions to be developed. However, these techniques do not necessarily identify the simplest RNA structures for performing their functions. Determining the simplest RNA that binds to a particular ligand is currently limited to experimental protocols. Here, we introduce a molecular-mechanics based algorithm employing molecular dynamics simulations and free-energy methods to predict the minimum sequence requirements for selective ligand binding to RNA. The algorithm involves iteratively deleting nucleotides from an experimentally determined structure of an RNA-ligand complex, performing energy minimizations and molecular dynamics on each truncated structure, and assessing which truncations do not prohibit RNA binding to the ligand. The algorithm allows prediction of the effects of sequence modifications on RNA structural stability and ligand-binding energy. We have implemented the algorithm in the AMBER suite of programs, but it could be implemented in any molecular mechanics force field parameterized for nucleic acids. Test cases are presented to show the utility and accuracy of the methodology.
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Affiliation(s)
- Peter C Anderson
- School of Pharmacy, University of Wisconsin, 777 Highland Avenue, Madison, Wisconsin 53705, USA
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Abstract
A systematic computational analysis of the ability of aromatic carbon-bound fluorine to participate in hydrogen bonding and electrostatic interactions has been completed. The interaction energies between the most common fluoroaromatics used in medicinal chemistry and both water, the prototypical hydrogen bond donor, and several cations have been calculated at different levels of theory (HF, MP2, DFT). Our results show that aromatic fluorine can participate in significant hydrogen bonds and can also interact with charged molecules.
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Affiliation(s)
- Andrew V Razgulin
- Department of Chemistry and School of Pharmacy, University of Wisconsin, 777 Highland Avenue, Madison, WI 53705, USA
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Abstract
We have recently introduced a computational methodology that combines molecular dynamics (MD) simulations, free-energy calculations, and in vitro binding assays to predict the minimum RNA structural requirements for selective, high-affinity RNA binding to small-molecule ligands. Here, we show that this methodology can be applied to the conformationally flexible aminoglycoside antibiotic paromomycin. A RNA consisting of an 11-mer:10-mer duplex that contains one 16S ribosome RNA decoding A-site bound to paromomycin was simulated for 4 ns. The methodology predicts that the 11-mer:10-mer duplex binds to paromomycin with high affinity, whereas smaller RNA duplexes lose complex stability and the ability to bind paromomycin. The predicted high-affinity binding to paromomycin of the 11-mer:10-mer duplex was confirmed experimentally (EC(50) = 0.28 microM), as well as the inability of smaller complexes to bind. Our simulations show good agreement with experiment for dynamic and structural properties of the isolated A-site, including hydrogen-bonding networks and RNA structural rearrangements upon ligand binding. The results suggest that MD simulations can supplement in vitro methods as a tool for predicting minimum RNA-binding motifs for both small, rigid ligands, and large, flexible ligands when structural information is available.
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Affiliation(s)
- Peter C Anderson
- School of Pharmacy, University of Wisconsin, 777 Highland Avenue, Madison, WI 53705, USA
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Woll MG, Hadley EB, Mecozzi S, Gellman SH. Stabilizing and Destabilizing Effects of Phenylalanine → F5-Phenylalanine Mutations on the Folding of a Small Protein. J Am Chem Soc 2006; 128:15932-3. [PMID: 17165695 DOI: 10.1021/ja0634573] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report a systematic evaluation of phenylalanine-to-pentafluorophenylalanine (Phe --> F5-Phe) mutants for the 35-residue chicken villin headpiece subdomain (c-VHP), the hydrophobic core of which features a cluster of three Phe side chains (residues 6, 10, and 17). Phe --> F5-Phe mutations are interesting because aryl-perfluoroaryl interactions of optimal geometry are intrinsically more favorable than aryl-aryl interactions and because perfluoroaryl units are more hydrophobic than are analogous aryl units. One mutant, Phe-10 --> F5-Phe, provides enhanced tertiary structural stability relative to the native sequence. The other six mutants analyzed caused a decrease in stability.
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Affiliation(s)
- Matthew G Woll
- Department of Chemistry and School of Pharmacy, University of Wisconsin, Madison, Wisconsin 53706, USA
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Affiliation(s)
| | - Sandro Mecozzi
- b Department of Chemistry , University of Wisconsin - Madison , 777 Highland Ave., Madison, WI 53705, USA
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Abstract
Aptamers are nucleic acids developed by in vitro evolution techniques that bind to specific ligands with high affinity and selectivity. Despite such high affinity and selectivity, however, in vitro evolution does not necessarily reveal the minimum structure of the nucleic acid required for selective ligand binding. Here, we show that a 35mer RNA aptamer for the cofactor flavin mononucleotide (FMN) identified by in vitro evolution can be computationally evolved to a mere 14mer structure containing the original binding pocket and eight scaffolding nucleotides while maintaining its ability to bind in vitro selectively to FMN. Using experimental and computational methodologies, we found that the 14mer binds with higher affinity to FMN (KD ∼ 4 µM) than to flavin adenine dinucleotide (KD ∼ 12 µM) or to riboflavin (KD ∼ 13 µM),despite the negative charge of FMN. Different hydrogen-bond strengths resulting from differing ring-system electron densities associated with the aliphatic-chain charges appear to contribute to the selectivity observed for the binding of the 14mer to FMN and riboflavin. Our results suggest that high affinity and selectivity in ligand binding is not restricted to large RNAs, but can also be a property of extraordinarily short RNAs.
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Affiliation(s)
- Peter C. Anderson
- School of Pharmacy, University of Wisconsin777 Highland Avenue, Madison, WI 53705, USA
| | - Sandro Mecozzi
- School of Pharmacy, University of Wisconsin777 Highland Avenue, Madison, WI 53705, USA
- Department of Chemistry, University of Wisconsin777 Highland Avenue, Madison, WI 53705, USA
- To whom correspondence should be addressed. Tel: +1 608 262 7810; Fax: +1 608 262 5345;
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Abstract
RNA plays critical roles in numerous biological processes and constitutes valuable therapeutic targets. RNA is significant not only for its roles in transmitting the genetic code but also for its enzymatic functions in ribozymes and in peptide bond formation in ribosomes. Recent studies have shown that RNAs containing as few as 22 nucleotides can be key elements in cellular functions. This suggests the possibility of using short RNAs as regulatory elements. Here, we show that ligand recognition and selectivity by RNA molecules can occur with only the presence of a binding pocket and as few as six additional scaffolding nucleotides holding the binding pocket in place. A 13-mer RNA truncation of a 33-mer aptamer for theophylline preserves the ability to bind to theophylline and to discriminate against the structurally similar compound caffeine. The truncated aptamer retains nearly all of the same structural elements in its binding site as those present in the original aptamer. This is the first demonstration of selective ligand binding by a 13-mer RNA.
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Affiliation(s)
- Peter C Anderson
- School of Pharmacy and Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53705, USA
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Abstract
A novel amphiphilic semifluorinated calix[4]arene has been shown to exhibit liquid crystalline character and to self-assemble in solvents of varying polarity.
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Affiliation(s)
- Oana M Martin
- School of Pharmacy, University of Wisconsin-Madison, 777 Highland Ave., Madison, WI 53705, USA
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Abstract
The physical and chemical properties of organic compounds are deeply affected by the introduction of fluorinated substituents. Perfluorinated and highly fluorinated organic molecules are both hydrophobic and lipophobic. This makes the recognition and the binding of fluorinated molecules extremely difficult to achieve through classical elements of molecular recognition. Here we show that semifluorinated water-soluble block copolymers can generate micellar structures having a fluorous phase-based inner core in aqueous solution. Furthermore, we show that these micelles can be used to encapsulate and bind highly fluorinated molecules through association in the internal fluorous phase (fluorophobic effect). We report that semifluorinated block copolymers can be used for the aqueous solubilization of the widely diffused gaseous anesthetic sevoflurane, thereby suggesting the possibility of the intravenous delivery of this commonly used anesthetic.
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Ngola SM, Kearney PC, Mecozzi S, Russell K, Dougherty DA. A Selective Receptor for Arginine Derivatives in Aqueous Media. Energetic Consequences of Salt Bridges That Are Highly Exposed to Water. J Am Chem Soc 1999. [DOI: 10.1021/ja982499r] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Meissner R, Garcias X, Mecozzi S, Rebek J. Synthesis and Assembly of New Molecular Hosts: Solvation and the Energetics of Encapsulation. J Am Chem Soc 1997. [DOI: 10.1021/ja962991f] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- R. Meissner
- Contribution from the Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037
| | - X. Garcias
- Contribution from the Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037
| | - S. Mecozzi
- Contribution from the Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037
| | - J. Rebek
- Contribution from the Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037
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Mecozzi S, West AP, Dougherty DA. Cation-pi interactions in aromatics of biological and medicinal interest: electrostatic potential surfaces as a useful qualitative guide. Proc Natl Acad Sci U S A 1996; 93:10566-71. [PMID: 8855218 PMCID: PMC38193 DOI: 10.1073/pnas.93.20.10566] [Citation(s) in RCA: 463] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The cation-pi interaction is an important, general force for molecular recognition in biological receptors. Through the sidechains of aromatic amino acids, novel binding sites for cationic ligands such as acetylcholine can be constructed. We report here a number of calculations on prototypical cation-pi systems, emphasizing structures of relevance to biological receptors and prototypical heterocycles of the type often of importance in medicinal chemistry. Trends in the data can be rationalized using a relatively simple model that emphasizes the electrostatic component of the cation-pi interaction. In particular, plots of the electrostatic potential surfaces of the relevant aromatics provide useful guidelines for predicting cation-pi interactions in new systems.
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Affiliation(s)
- S Mecozzi
- Arnold and Mabel Beckman Laboratories of Chemical Synthesis, California Institute of Technology, Pasadena 91125, USA
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Affiliation(s)
- Sandro Mecozzi
- Contribution No. 9162 from the Arnold and Mabel Beckman Laboratories of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
| | - Anthony P. West
- Contribution No. 9162 from the Arnold and Mabel Beckman Laboratories of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
| | - Dennis A. Dougherty
- Contribution No. 9162 from the Arnold and Mabel Beckman Laboratories of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
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