2023
[November]
November 4: Congratulations to Zofia and co-workers for their recent publication “Topical application of synthetic melanin promotes tissue repair” in npj Regenerative Medicine.
[March]
March 8: Cheers to Maria’s new Central Science paper examining the Ouzo effect via liquid phase transmission electron microscopy being featured by the following news outlets. Yasou!
Phys.org
Science Daily
EurekaAlert!
ScienMag
News Azi
SciTechDaily
[January]
January 16: Organic solution-phase transmission electron microscopy of copolymer nanoassembly morphology and dynamics has been selected for Cell Reports Physical Science Editors Choice, 2022.
2022
[November]
November 15: Congratulations to graduate student Mara Fattah for being named a Ryan Fellow!
[October]
October 31: Congratulations to graduate students Joanna Korpanty and Mara Fattah for receiving awards at their Gordon Research Conferences! Joanna received a poster award at the GRC for Liquid Phase Electron Microscopy and Mara was awarded Outstanding Oral Presentation at the Chemistry and Biology of Peptides GRS. Nicely done!
[August]
August 12: Undergraduate researcher JoJo Holms has been awarded the prestigious Lambert Fellowship by the Chemistry of Life Processes Institute. Read more here.
[March]
March 3: Northwestern Now has featured our work using mussel proteins as a bioinspired synthetic adhesive, recently published by Dr. Or Berger in JACS. Congrats Or! Check out the features in the other news outlets below:
[February]
February 17: Joanna Korpanty’s recent paper in Cell Reports Physical Science has been featured in several news outlets! See stories below. Congrats Joanna!
Northwestern Now
International Institute for Nanotechnology
Eureka
McCormick School of Engineering
2021
[November]
November 30: Fourth year graduate student Joanna Korpanty’s recent paper in Nature communications has been featured in the Editors’ Highlights of research in Materials Science and Chemistry. Congrats Joanna!
[July]
July 22: Our recent work investigating the evolution of melanin in the wings of seabirds has been featured in several news outlets!
New Atlas
Phys. Org
Science
The Naked Scientists
[March]
March 25: Second year Chemistry student Omar Ebrahim has been awarded a National Science Foundation Graduate Research Fellowship. Congrats Omar!
March 11: Third year Materials Science and Engineering student Maria Vratsanos has been named a Dr. John N. Nicholson Fellow for the 2021-2022 school term.
March 08: Northwestern Now has featured our recent JACS paper on using bioinspired synthetic melanin as a natural detoxifier, and it has been featured in several other news outlets!
2020
[December]
December 22: Northwestern Now and Eureka Alert have covered our recent paper on using VT-LCTEM to visualize the PISA process from group alumnae Dr. Mollie Touve and Dr. Andrea Carlini.
[August]
August 24: Harvard University’s Science in the News blog covered Dr. Wei Cao’s selenomelanin paper!
August 17: What Da Math?’s new video is an excellent overview of the recent selenomelanin paper, with a focus on its significance for space travel.
August 7: The Selenomelanin paper continues to be covered in a variety of news outlets! Congratulations, everyone!
[July]
July 29: The Selenomelanin JACS paper has been covered in Materials Today, Nano Today, So Cool So Good, Live Science, and The Daily Mail (UK)!
July 13: The group’s recent JACS paper has been featured on today’s edition of C&EN, on the JACS Twitter account, The Latest News, and Science Daily!
July 12: The Selenomelanin paper was featured The 5 Coolest Things on Earth This Week!
July 8: The JACS paper, Selenomelanin: An Abiotic Selenium Analogue of Pheomelanin, by seven members of the lab group has been covered by several news sites!
[June]
June 24: The recent paper, Paclitaxel-terminated peptide brush polymers, by Jialei Zhu and former and current group members Doctors Hao Sun, Cassandra Callmann, Matt Thompson, Claudia Battistella, Maria Proetto, and Andrea Carlini was accepted a the back cover article for the latest issue of Chemical Communications. Congratulations, everyone!
[May]
May 5: Dr. Claudia Battistella’s melanin-based hair dye paper has been covered by a wide variety of news outlets, and ranks in the top 5% of all Altmetric research outputs!
New Atlas
Technology Networks – Covering the Grey a Safer Way
MDR (German)
EurekAlert
Environmental News Network
The Medical News
Science Daily
Newswise
Phys.org
May 4: Dr. Claudia Battistella’s paper on melanin-based hair dyes has been covered extensively in Italian newspapers!
The Medical News
ANSA
ADN Kronos
IL Digitale
Sky TG24
May 3: Chemical & Engineering News’ (C&EN’s) May cover story focuses on new epidemiological studies that correlate the use of long-lasting hair dyes with increased risk of breast cancer. Dr. Claudia Battistella’s new technique of using synthetic melanin and mild application conditions is featured as a potential solution, as it does not require any of the chemicals attributed to the increased cancer risk! Well done Claudia!
[April]
April 29: Dr. Claudia Battistella’s new paper in ACS Central Science on using synthetic melanin as a gentler, safer method of dying hair was covered in Northwestern Now!
[March]
March 27: Nathan was named a 2020 American Institute for Medical and Biological Engineering (AIMBE) Fellow! Election to AIMBE is among the highest distinctions accorded to medical and biological engineers. Congratulations Nathan!
March 16: Covid-19 precautions may limit in-person contact, but that just means that group meetings happen online now! Though we’re not sure how the no-laptop-at-group-meeting rule works for online meetings…
March 15: Recent graduates Dr. Andrea Carlini and Dr. Mollie Touve and current group member Joanna Korpanty’s Nature Communications paper on 4D nanoscale printing was covered in CUNY Advanced Science Research Center news bulletin and in CEN news! Congratulations on the awesome paper!
2019
[November]
November 18: Dr. Nanzhi Zang successfully defended her thesis, Polymeric Nanostructures as Tools for Neuroanatomy, becoming the 17th Gianneschi group graduate!
November 4: Dr. Hao Sun and Wonmin Choi’s paper on using photoinduce reversible-deactivation radical polymerization (photo-RDRP) to make poly(peptide) brush polymers earned the cover of Angewandte Chemie!
[October]
October 23: Dr. Mollie Touve & Dr. Andrea Carlini’s paper on combining in situ LC-TEM imaging with MALDI-IMS post mortem analysis was published in Nature Communications.
Simpson Querrey Institute Press Release
[August]
August 13: Dr. Mollie Touve, the 16th graduate from the Gianneschi group and the first from Northwestern, successfully defended her thesis, and in the Finnish tradition was presented with her doctoral sword and top hat!
[July 2019]
July 30: The Naked Scientists, a UK science podcast site, interviewed Nathan about how the “Trojan Horse” drug delivery technique works.
July 24: Nathan was interviewed about Cassi’s new “Trojan Horse” anti-cancer paper by WGN radio! Listen to the interview here.
July 19: Postdoc Dr. Karthikeyan Gnanasekaran’s paper on liquid cell transmission electron microscopy (LC-TEM) of Metal-Organic Nanotubes (MONTs) was featured as an Editor’s Choice in Science!
July 18: Group alum Dr. Cassi Callmann’s new paper on “Trojan Horse” anti-cancer drugs was just published. This method of disguising anticancer drugs as fat molecules allows for higher concentrations of anticancer drugs to be delivered much more selectively to tumors. Congratulations on the excellent paper Cassi!
NU Chemistry of Life Processes Institute
GE Reports – The Coolest Things on Earth This Week (Check out #5!)
[April 2019]
+ See Nathan’s writeup on our new publication in Nature Communications. The work stemmed from years of effort and leadership by first author and alum, Dr. Andrea Carlini. Congrats on a fantastic paper Andrea!
ScienMag
Science Daily
Eureka Alert
Medical Xpress
Xinhua
+ Congratulations to Ioannina Castano and Maria Vratsanos as recipients of this year’s National Science Foundation Graduation Research Fellowships!
2018
[December, 2018]
+ We develop a hybrid computational and biochemical method to rapidly optimize peptides for specific, orthogonal biochemical functions. The method is an iterative machine learning process by which experimental data is deposited into a mathematical algorithm that selects potential peptide substrates to be tested experimentally. Once tested, the algorithm uses the experimental data to refine future selections. This process is repeated until a suitable set of de novo peptide substrates are discovered. We employed this technology to discover orthogonal peptide substrates for 4′-phosphopantetheinyl transferase, an enzyme class that covalently modifies proteins. In this manner, we have demonstrated that machine learning can be leveraged to guide peptide optimization for specific biochemical functions not immediately accessible by biological screening techniques, such as phage display and random mutagenesis.
News and Highlights:
R&D
Long Room
Phys.org
Nanowerk
EurekAlert!
Science Daily
+ We report phosphorescent Pt(II) complexes as monomers which can be directly incorporated into growing polymers. Due to the amphiphilic nature of the polymers they can self-assemble into micellar nanoparticles, where the phosphorescent Pt(II) complexes can arrange selectively in the core or shell of the nanoparticles. The complexes enable dual orthogonal imaging, made possible by the heavy metal, which enhances the contrast for these micelles in electron microscopy and facilitates spin-orbit coupling that turns on microsecond lifetime luminescence.
[October, 2018]
+ We determine the physical form of the natural spidroin precursor nanostructures stored within spider glands that seed the formation of their silks and reveal the fundamental structural transformations that occur during the initial stages of extrusion en route to fiber formation. Using a combination of solution phase diffusion NMR and cryogenic transmission electron microscopy (cryo-TEM), we reveal direct evidence that the concentrated spidroin proteins are stored in the silk glands of black widow spiders as complex, hierarchical nanoassemblies (~300 nm diameter) that are composed of micellar subdomains, substructures that themselves are engaged in the initial nanoscale transformations that occur in response to shear. We find that the established micelle theory of silk fiber precursor storage is incomplete and that the first steps toward liquid crystalline organization during silk spinning involve the fibrillization of nanoscale hierarchical micelle subdomains.
**Photo credit: Holland Lab, SDSU
News and Highlights:
The Washington Post
DailyMail
EurekAlert! AAAS
Cosmos
Northwestern Now
SDSU NewsCenter
Popular Science
[October, 2018]
+ We determine the physical form of the natural spidroin precursor nanostructures stored within spider glands that seed the formation of their silks and reveal the fundamental structural transformations that occur during the initial stages of extrusion en route to fiber formation. Using a combination of solution phase diffusion NMR and cryogenic transmission electron microscopy (cryo-TEM), we reveal direct evidence that the concentrated spidroin proteins are stored in the silk glands of black widow spiders as complex, hierarchical nanoassemblies (~300 nm diameter) that are composed of micellar subdomains, substructures that themselves are engaged in the initial nanoscale transformations that occur in response to shear. We find that the established micelle theory of silk fiber precursor storage is incomplete and that the first steps toward liquid crystalline organization during silk spinning involve the fibrillization of nanoscale hierarchical micelle subdomains.
**Photo credit: Holland Lab, SDSU
News and Highlights:
The Washington Post
DailyMail
EurekAlert! AAAS
Cosmos
Northwestern Now
SDSU NewsCenter
Popular Science
[September, 2018]
+ We describe nanoparticles capable of Enzyme-Directed Assembly of Particle Therapeutics (EDAPT), containing an analog of the Pt(II)-containing drug oxaliplatin, an 15N-labeled monomer in the hydrophobic block of the backbone of the polymer, the near-infrared dye Cy5.5, and a peptide that is a substrate for tumor metalloproteinases in the hydrophilic block. To evaluate the distribution of drug and EDAPT carrier in vivo, we correlate the localization of the isotopically labeled polymer backbone and Pt by NanoSIMS with super-resolution fluorescence microscopy of the polymer to monitor release of drug from the nanocarrier and co-localization with cellular DNA within tumor tissue. These techniques are powerful for the elucidation of the localization of cargo and carrier, and enable a high-resolution assessment of their performance following in vivo delivery.
+ We describe the use of liquid cell transmission electron microscopy (LCTEM) for inducing and imaging the formation of spherical micelles from amphiphilic block copolymers. We demonstrate that nanoparticle formation can be visualized in situ and that in the presence of excess monomer, nanoparticle growth occurs to yield sizes and morphologies consistent with standard PISA conditions.
+ Congratulations to Cassandra Callmann for being awarded the Department of Chemistry and Biochemistry 2017-18 Oustanding Dissertation Award. She is one of six recipients of this award.
+ Congratulations to Nathan C. Gianneschi, who has been name associate director of the International Institute for Nanotechnology at Northwestern!
[April, 2018]
+ We report open-to-air aqueous-phase ring-opening metathesis polymerization-induced self-assembly (ROMPISA) for forming well-defined peptide polymer nanoparticles at room temperature and with high solids concentrations (10 w/w%). For these materials, ROMPISA is shown to provide control over molecular weight with high conversion while open-to-air. Moreover, these peptide polymer nanoparticles can spontaneously rearrange into larger aggregate scaffolds in the presence of the proteolytic enzyme, thermolysin. This work demonstrates the robust nature of ROMPISA, highlighted here for the preparation of stimuli-responsive nanostructures in one pot, in air.
News and Highlights:
Northwestern Now
Microscopy and Analysis
UF News
ScienceDaily
Breitbart
[March, 2018]
+ Congratulations to Karthikeyan Gnanasekaran for being awarded the International Human Frontier Science Program Fellowship (HFSP). This award funds 3 years of post-doctoral research for early career scientists to broaden their research skills by moving into new areas of study while working in a new country.
+ We report aqueous-phase Ring-Opening Metathesis Polymerization-Induced Self-Assembly (ROMPISA) for forming well-defined micellar polymer nanoparticles at room temperature and high solids concentration (20 w/w%). This is achieved with a new polymerization initiator, in the form of a water-soluble cationic Hoveyda-Grubbs second generation catalyst. This reaction was used in water to produce diblock copolymers from norbornenyl monomers, which then self-assemble into myriad nanostructure morphologies for which a phase diagram was constructed. Additionally, the living nature of the polymerization initiated by the aqueous initiator was confirmed, as shown by kinetic evaluation under mild conditions in water.
[February, 2018]
We report the synthesis of families of amphiphilic polymers that differ in (i) side-chain molecular structure, (ii) polymer architecture, and (iii) copolymer composition. We used this library in experiments to establish structure-property relationships relevant to the design of multi-functional polymers that can amplify and transduce biomolecular recognition events into optically detectable, macroscopic ordering transitions in LCs. We then utilized these structure-property relationships to guide the design of a peptide-polymer amphiphile (PPAs) that assembles at the interface of LC droplets. Enzymatic cleavage of PPA-coated LC droplets by thermolysin directly triggered a change in the internal ordering of the LC within the droplets and the scattering of light from the droplets. The results of our study provide important guidance to future designs of triggerable LC systems.
[January, 2018]
We develop novel RNA-polymer amphiphiles that assemble into spherical micellar nanoparticles with diameters of ca. 15�30 nm and efficiently enter live cells without transfection reagents. The surface-displayed RNA remains accessible for hybridization with complementary RNA. Chemical modification of the termini of hybridized RNA strands has a tremendous impact on cellular internalization efficiencies. The display of hydrophobic dabcyl or stilbene units dramatically increased cell uptake, whereas hydrophilic neutral hydroxy or anionic phosphate residues were ineffective. Interestingly, neither of these modifications mediated noticeable uptake of free RNA oligonucleotides. We infer that their high density display on micellar nanoparticle surfaces is key for the observed effect; achieved with local effective surface concentrations in the millimolar range. We speculate that weak interactions with cell surface receptors that are amplified by the multivalent presentation of such modifications may be responsible. The installation of small molecule ligands on nanomaterial surfaces via hybridization of chemically modified oligonucleotides offers a simple and straightforward way to modulate cellular uptake of nanoparticles.
2023
[January]
January 16: Organic solution-phase transmission electron microscopy of copolymer nanoassembly morphology and dynamics has been selected for Cell Reports Physical Science Editors Choice, 2022.
2022
[November]
November 15: Congratulations to graduate student Mara Fattah for being named a Ryan Fellow!
[October]
October 31: Congratulations to graduate students Joanna Korpanty and Mara Fattah for receiving awards at their Gordon Research Conferences! Joanna received a poster award at the GRC for Liquid Phase Electron Microscopy and Mara was awarded Outstanding Oral Presentation at the Chemistry and Biology of Peptides GRS. Nicely done!
[August]
August 12: Undergraduate researcher JoJo Holms has been awarded the prestigious Lambert Fellowship by the Chemistry of Life Processes Institute. Read more here.
[March]
March 3: Northwestern Now has featured our work using mussel proteins as a bioinspired synthetic adhesive, recently published by Dr. Or Berger in JACS. Congrats Or! Check out the features in the other news outlets below:
[February]
February 17: Joanna Korpanty’s recent paper in Cell Reports Physical Science has been featured in several news outlets! See stories below. Congrats Joanna!
Northwestern Now
International Institute for Nanotechnology
Eureka
McCormick School of Engineering
2021
[November]
November 30: Fourth year graduate student Joanna Korpanty’s recent paper in Nature communications has been featured in the Editors’ Highlights of research in Materials Science and Chemistry. Congrats Joanna!
[July]
July 22: Our recent work investigating the evolution of melanin in the wings of seabirds has been featured in several news outlets!
New Atlas
Phys. Org
Science
The Naked Scientists
[March]
March 25: Second year Chemistry student Omar Ebrahim has been awarded a National Science Foundation Graduate Research Fellowship. Congrats Omar!
March 11: Third year Materials Science and Engineering student Maria Vratsanos has been named a Dr. John N. Nicholson Fellow for the 2021-2022 school term.
March 08: Northwestern Now has featured our recent JACS paper on using bioinspired synthetic melanin as a natural detoxifier, and it has been featured in several other news outlets!
2020
[December]
December 22: Northwestern Now and Eureka Alert have covered our recent paper on using VT-LCTEM to visualize the PISA process from group alumnae Dr. Mollie Touve and Dr. Andrea Carlini.
[August]
August 24: Harvard University’s Science in the News blog covered Dr. Wei Cao’s selenomelanin paper!
August 17: What Da Math?’s new video is an excellent overview of the recent selenomelanin paper, with a focus on its significance for space travel.
August 7: The Selenomelanin paper continues to be covered in a variety of news outlets! Congratulations, everyone!
[July]
July 29: The Selenomelanin JACS paper has been covered in Materials Today, Nano Today, So Cool So Good, Live Science, and The Daily Mail (UK)!
July 13: The group’s recent JACS paper has been featured on today’s edition of C&EN, on the JACS Twitter account, The Latest News, and Science Daily!
July 12: The Selenomelanin paper was featured The 5 Coolest Things on Earth This Week!
July 8: The JACS paper, Selenomelanin: An Abiotic Selenium Analogue of Pheomelanin, by seven members of the lab group has been covered by several news sites!
[June]
June 24: The recent paper, Paclitaxel-terminated peptide brush polymers, by Jialei Zhu and former and current group members Doctors Hao Sun, Cassandra Callmann, Matt Thompson, Claudia Battistella, Maria Proetto, and Andrea Carlini was accepted a the back cover article for the latest issue of Chemical Communications. Congratulations, everyone!
[May]
May 5: Dr. Claudia Battistella’s melanin-based hair dye paper has been covered by a wide variety of news outlets, and ranks in the top 5% of all Altmetric research outputs!
New Atlas
Technology Networks – Covering the Grey a Safer Way
MDR (German)
EurekAlert
Environmental News Network
The Medical News
Science Daily
Newswise
Phys.org
May 4: Dr. Claudia Battistella’s paper on melanin-based hair dyes has been covered extensively in Italian newspapers!
The Medical News
ANSA
ADN Kronos
IL Digitale
Sky TG24
May 3: Chemical & Engineering News’ (C&EN’s) May cover story focuses on new epidemiological studies that correlate the use of long-lasting hair dyes with increased risk of breast cancer. Dr. Claudia Battistella’s new technique of using synthetic melanin and mild application conditions is featured as a potential solution, as it does not require any of the chemicals attributed to the increased cancer risk! Well done Claudia!
[April]
April 29: Dr. Claudia Battistella’s new paper in ACS Central Science on using synthetic melanin as a gentler, safer method of dying hair was covered in Northwestern Now!
[March]
March 27: Nathan was named a 2020 American Institute for Medical and Biological Engineering (AIMBE) Fellow! Election to AIMBE is among the highest distinctions accorded to medical and biological engineers. Congratulations Nathan!
March 16: Covid-19 precautions may limit in-person contact, but that just means that group meetings happen online now! Though we’re not sure how the no-laptop-at-group-meeting rule works for online meetings…
March 15: Recent graduates Dr. Andrea Carlini and Dr. Mollie Touve and current group member Joanna Korpanty’s Nature Communications paper on 4D nanoscale printing was covered in CUNY Advanced Science Research Center news bulletin and in CEN news! Congratulations on the awesome paper!
2019
[November]
November 18: Dr. Nanzhi Zang successfully defended her thesis, Polymeric Nanostructures as Tools for Neuroanatomy, becoming the 17th Gianneschi group graduate!
November 4: Dr. Hao Sun and Wonmin Choi’s paper on using photoinduce reversible-deactivation radical polymerization (photo-RDRP) to make poly(peptide) brush polymers earned the cover of Angewandte Chemie!
[October]
October 23: Dr. Mollie Touve & Dr. Andrea Carlini’s paper on combining in situ LC-TEM imaging with MALDI-IMS post mortem analysis was published in Nature Communications.
Simpson Querrey Institute Press Release
[August]
August 13: Dr. Mollie Touve, the 16th graduate from the Gianneschi group and the first from Northwestern, successfully defended her thesis, and in the Finnish tradition was presented with her doctoral sword and top hat!
[July 2019]
July 30: The Naked Scientists, a UK science podcast site, interviewed Nathan about how the “Trojan Horse” drug delivery technique works.
July 24: Nathan was interviewed about Cassi’s new “Trojan Horse” anti-cancer paper by WGN radio! Listen to the interview here.
July 19: Postdoc Dr. Karthikeyan Gnanasekaran’s paper on liquid cell transmission electron microscopy (LC-TEM) of Metal-Organic Nanotubes (MONTs) was featured as an Editor’s Choice in Science!
July 18: Group alum Dr. Cassi Callmann’s new paper on “Trojan Horse” anti-cancer drugs was just published. This method of disguising anticancer drugs as fat molecules allows for higher concentrations of anticancer drugs to be delivered much more selectively to tumors. Congratulations on the excellent paper Cassi!
NU Chemistry of Life Processes Institute
GE Reports – The Coolest Things on Earth This Week (Check out #5!)
[April 2019]
+ See Nathan’s writeup on our new publication in Nature Communications. The work stemmed from years of effort and leadership by first author and alum, Dr. Andrea Carlini. Congrats on a fantastic paper Andrea!
ScienMag
Science Daily
Eureka Alert
Medical Xpress
Xinhua
+ Congratulations to Ioannina Castano and Maria Vratsanos as recipients of this year’s National Science Foundation Graduation Research Fellowships!
2018
[December, 2018]
+ We develop a hybrid computational and biochemical method to rapidly optimize peptides for specific, orthogonal biochemical functions. The method is an iterative machine learning process by which experimental data is deposited into a mathematical algorithm that selects potential peptide substrates to be tested experimentally. Once tested, the algorithm uses the experimental data to refine future selections. This process is repeated until a suitable set of de novo peptide substrates are discovered. We employed this technology to discover orthogonal peptide substrates for 4′-phosphopantetheinyl transferase, an enzyme class that covalently modifies proteins. In this manner, we have demonstrated that machine learning can be leveraged to guide peptide optimization for specific biochemical functions not immediately accessible by biological screening techniques, such as phage display and random mutagenesis.
News and Highlights:
R&D
Long Room
Phys.org
Nanowerk
EurekAlert!
Science Daily
+ We report phosphorescent Pt(II) complexes as monomers which can be directly incorporated into growing polymers. Due to the amphiphilic nature of the polymers they can self-assemble into micellar nanoparticles, where the phosphorescent Pt(II) complexes can arrange selectively in the core or shell of the nanoparticles. The complexes enable dual orthogonal imaging, made possible by the heavy metal, which enhances the contrast for these micelles in electron microscopy and facilitates spin-orbit coupling that turns on microsecond lifetime luminescence.
[October, 2018]
+ We determine the physical form of the natural spidroin precursor nanostructures stored within spider glands that seed the formation of their silks and reveal the fundamental structural transformations that occur during the initial stages of extrusion en route to fiber formation. Using a combination of solution phase diffusion NMR and cryogenic transmission electron microscopy (cryo-TEM), we reveal direct evidence that the concentrated spidroin proteins are stored in the silk glands of black widow spiders as complex, hierarchical nanoassemblies (~300 nm diameter) that are composed of micellar subdomains, substructures that themselves are engaged in the initial nanoscale transformations that occur in response to shear. We find that the established micelle theory of silk fiber precursor storage is incomplete and that the first steps toward liquid crystalline organization during silk spinning involve the fibrillization of nanoscale hierarchical micelle subdomains.
**Photo credit: Holland Lab, SDSU
News and Highlights:
The Washington Post
DailyMail
EurekAlert! AAAS
Cosmos
Northwestern Now
SDSU NewsCenter
Popular Science
[October, 2018]
+ We determine the physical form of the natural spidroin precursor nanostructures stored within spider glands that seed the formation of their silks and reveal the fundamental structural transformations that occur during the initial stages of extrusion en route to fiber formation. Using a combination of solution phase diffusion NMR and cryogenic transmission electron microscopy (cryo-TEM), we reveal direct evidence that the concentrated spidroin proteins are stored in the silk glands of black widow spiders as complex, hierarchical nanoassemblies (~300 nm diameter) that are composed of micellar subdomains, substructures that themselves are engaged in the initial nanoscale transformations that occur in response to shear. We find that the established micelle theory of silk fiber precursor storage is incomplete and that the first steps toward liquid crystalline organization during silk spinning involve the fibrillization of nanoscale hierarchical micelle subdomains.
**Photo credit: Holland Lab, SDSU
News and Highlights:
The Washington Post
DailyMail
EurekAlert! AAAS
Cosmos
Northwestern Now
SDSU NewsCenter
Popular Science
[September, 2018]
+ We describe nanoparticles capable of Enzyme-Directed Assembly of Particle Therapeutics (EDAPT), containing an analog of the Pt(II)-containing drug oxaliplatin, an 15N-labeled monomer in the hydrophobic block of the backbone of the polymer, the near-infrared dye Cy5.5, and a peptide that is a substrate for tumor metalloproteinases in the hydrophilic block. To evaluate the distribution of drug and EDAPT carrier in vivo, we correlate the localization of the isotopically labeled polymer backbone and Pt by NanoSIMS with super-resolution fluorescence microscopy of the polymer to monitor release of drug from the nanocarrier and co-localization with cellular DNA within tumor tissue. These techniques are powerful for the elucidation of the localization of cargo and carrier, and enable a high-resolution assessment of their performance following in vivo delivery.
+ We describe the use of liquid cell transmission electron microscopy (LCTEM) for inducing and imaging the formation of spherical micelles from amphiphilic block copolymers. We demonstrate that nanoparticle formation can be visualized in situ and that in the presence of excess monomer, nanoparticle growth occurs to yield sizes and morphologies consistent with standard PISA conditions.
+ Congratulations to Cassandra Callmann for being awarded the Department of Chemistry and Biochemistry 2017-18 Oustanding Dissertation Award. She is one of six recipients of this award.
+ Congratulations to Nathan C. Gianneschi, who has been name associate director of the International Institute for Nanotechnology at Northwestern!
[April, 2018]
+ We report open-to-air aqueous-phase ring-opening metathesis polymerization-induced self-assembly (ROMPISA) for forming well-defined peptide polymer nanoparticles at room temperature and with high solids concentrations (10 w/w%). For these materials, ROMPISA is shown to provide control over molecular weight with high conversion while open-to-air. Moreover, these peptide polymer nanoparticles can spontaneously rearrange into larger aggregate scaffolds in the presence of the proteolytic enzyme, thermolysin. This work demonstrates the robust nature of ROMPISA, highlighted here for the preparation of stimuli-responsive nanostructures in one pot, in air.
News and Highlights:
Northwestern Now
Microscopy and Analysis
UF News
ScienceDaily
Breitbart
[March, 2018]
+ Congratulations to Karthikeyan Gnanasekaran for being awarded the International Human Frontier Science Program Fellowship (HFSP). This award funds 3 years of post-doctoral research for early career scientists to broaden their research skills by moving into new areas of study while working in a new country.
+ We report aqueous-phase Ring-Opening Metathesis Polymerization-Induced Self-Assembly (ROMPISA) for forming well-defined micellar polymer nanoparticles at room temperature and high solids concentration (20 w/w%). This is achieved with a new polymerization initiator, in the form of a water-soluble cationic Hoveyda-Grubbs second generation catalyst. This reaction was used in water to produce diblock copolymers from norbornenyl monomers, which then self-assemble into myriad nanostructure morphologies for which a phase diagram was constructed. Additionally, the living nature of the polymerization initiated by the aqueous initiator was confirmed, as shown by kinetic evaluation under mild conditions in water.
[February, 2018]
We report the synthesis of families of amphiphilic polymers that differ in (i) side-chain molecular structure, (ii) polymer architecture, and (iii) copolymer composition. We used this library in experiments to establish structure-property relationships relevant to the design of multi-functional polymers that can amplify and transduce biomolecular recognition events into optically detectable, macroscopic ordering transitions in LCs. We then utilized these structure-property relationships to guide the design of a peptide-polymer amphiphile (PPAs) that assembles at the interface of LC droplets. Enzymatic cleavage of PPA-coated LC droplets by thermolysin directly triggered a change in the internal ordering of the LC within the droplets and the scattering of light from the droplets. The results of our study provide important guidance to future designs of triggerable LC systems.
[January, 2018]
We develop novel RNA-polymer amphiphiles that assemble into spherical micellar nanoparticles with diameters of ca. 15�30 nm and efficiently enter live cells without transfection reagents. The surface-displayed RNA remains accessible for hybridization with complementary RNA. Chemical modification of the termini of hybridized RNA strands has a tremendous impact on cellular internalization efficiencies. The display of hydrophobic dabcyl or stilbene units dramatically increased cell uptake, whereas hydrophilic neutral hydroxy or anionic phosphate residues were ineffective. Interestingly, neither of these modifications mediated noticeable uptake of free RNA oligonucleotides. We infer that their high density display on micellar nanoparticle surfaces is key for the observed effect; achieved with local effective surface concentrations in the millimolar range. We speculate that weak interactions with cell surface receptors that are amplified by the multivalent presentation of such modifications may be responsible. The installation of small molecule ligands on nanomaterial surfaces via hybridization of chemically modified oligonucleotides offers a simple and straightforward way to modulate cellular uptake of nanoparticles.