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Thursday, 12 May 2016

Alex M. Szpilman

Alex M. Szpilman

Alex M. Szpilman

Assistant Professor at Technion Israel Institute of Technology
LINKS

 

HeaderSummary

Specialties:
Organic chemistry
Organic synthesis
Reaction design and development
Physical organic chemistry
Chemical biology
Total synthesis of natural products
Mechanism of action of biologically active molecules
Asymmetric catalysis
Frontis

Experience

Assistant Professor

Technion Israel Institute of Technology
 – Present (7 years 3 months)

postdoc

ETH Zurich
 –  (6 years)

Education

Weizmann Institute of Science

Doctor of Philosophy (Ph.D.)

Danmarks Tekniske Universitet

M. Sc., Chemistry

Frederiksborg Gymnasium

 

Alex M Szpilman

Publications

Water Soluble Amphotericin B-PEG Conjugates with Low Toxicity and Potent In Vivo Efficacy(Link)

Journal of Medicinal Chemistry
January 14, 2016
Systemic fungal infections are an increasingly prevalent health problem, especially among immunocompromised patients. Antifungal drug development lags far behind in comparison to other types of antimicrobial drugs. Current commercially available antifungals are limited by their insufficient potency, side effects, drug–drug interactions, developing drug-resistance, and narrow formulation options....more

Design Concept for α-Hydrogen Substituted Nitroxides(Link)

Nature Communications
February 6, 2015
Stable nitroxides (nitroxyl radicals) have many essential and unique applications in chemistry,
biology and medicine. However, the factors influencing their stability are still under
investigation, and this hinders the design and development of new nitroxides. Nitroxides with
tertiary alkyl groups are generally stable but obviously highly encumbered. In contrast,
a-hydrogen-substituted...more

Synthesis and stability of cyclic α-hydrogen nitroxides(Link)

Organic & Biomolecular Chemistry
August 20, 2015
Selected as a HOT paper:
Nitroxides (nitroxyl radicals) hold a unique place in science due to their stable radical nature. We have recently reported the first design concept providing a general solution to the problem of designing and preparing monocyclic α-hydrogen nitroxides. The initial studies were limited to aryl derivatives. We now report a wider study showing that alkyl substituents may...more

Catalytic Aerobic Oxidation of Alcohols using Recoverable IAPNO α-Hydrogen Nitroxyl Radicals(Link)

ChemCatChem
March 12, 2015
α-Hydrogen-substituted nitroxyl radicals are of considerable interest as catalysts for oxidation and polymerization, but are usually inherently unstable. We report herein the catalytic activity of a new family of stable iso-azaphenalene (IAPNO) α-hydrogen nitroxyl radicals in the copper/bipyridine/N-methylimidazole co-catalyzed aerobic oxidation of alcohols. The nitroxyl radical Mes/TIPSO-IAPNO (...more

Oxidative Asymmetric Umpolung Alkylation of Evans’ β-Keto Imides by Dialkylzinc Nucleophiles(Link)

Organic and Biomolecular Chemistry
January 12, 2015
Seleected as a HOT paper:
Umpolung alkylation of Evans’ auxiliary substituted β-ketoimides affords the diastereomerically pure products in yields ranging from 40-80%. The reaction itself proceeds with diastereoselectivities between 3:1 and 18:1. Dialkylzinc serves as the nucleophile and umpolung of the β-keto-imide enolate is achieved by the action of Koser’s reagent.

Oxidative Umpolung α-Alkylation of Ketones(Link)

Organic Letters
January 6, 2015
We disclose a hypervalent iodine mediated α-alkylative umpolung reaction of carbonyl compounds with dialkylzinc as the alkyl source. The reaction is applicable to all common classes of ketones including 1,3-dicarbonyl compounds and regular ketones via their lithium enolates. The α-alkylated carbonyl products are formed in up to 93% yield. An ionic mechanism is inferred based on meticulous analysis...more

Synthetic and Mechanistic Study of the Catalytic Enantioselective Preparation of Primary β-Aminoketones from Enones and a Fluorinated Gabriel Reagent(Link)

ACS Catalysis
November 19, 2014
Salen μ-oxo complex of aluminum catalyzes the asymmetric 1,4-addition of the novel ammonia equivalent 3,4,5,6-tetrafluorophthalimide to unsaturated ketones. All of the reagents are inexpensive and are readily available. The products are formed in up to 89% yield and up to 96% ee. The tetrafluorophthalimide group is removed under mild chemoselective conditions and in high yields to afford the free...more

Probing the Biology of Natural Products: Molecular Editing by Diverted Total Synthesis(Link)

Angewandte Chemie
November 2010
The systematic modification of natural products through diverted total synthesis is a powerful concept for the systematic modification of natural products with the aim of studying mechanistic aspects of their biological activity. This concept offers far-reaching opportunities for discovery at the interface of biology and chemistry. It is underpinned by the power of chemical synthesis, which...more

Publications

Water Soluble Amphotericin B-PEG Conjugates with Low Toxicity and Potent In Vivo Efficacy(Link)

Journal of Medicinal Chemistry
January 14, 2016
Systemic fungal infections are an increasingly prevalent health problem, especially among immunocompromised patients. Antifungal drug development lags far behind in comparison to other types of antimicrobial drugs. Current commercially available antifungals are limited by their insufficient potency, side effects, drug–drug interactions, developing drug-resistance, and narrow formulation options....more

Design Concept for α-Hydrogen Substituted Nitroxides(Link)

Nature Communications
February 6, 2015
Stable nitroxides (nitroxyl radicals) have many essential and unique applications in chemistry,
biology and medicine. However, the factors influencing their stability are still under
investigation, and this hinders the design and development of new nitroxides. Nitroxides with
tertiary alkyl groups are generally stable but obviously highly encumbered. In contrast,
a-hydrogen-substituted...more

Synthesis and stability of cyclic α-hydrogen nitroxides(Link)

Organic & Biomolecular Chemistry
August 20, 2015
Selected as a HOT paper:
Nitroxides (nitroxyl radicals) hold a unique place in science due to their stable radical nature. We have recently reported the first design concept providing a general solution to the problem of designing and preparing monocyclic α-hydrogen nitroxides. The initial studies were limited to aryl derivatives. We now report a wider study showing that alkyl substituents may...more

Catalytic Aerobic Oxidation of Alcohols using Recoverable IAPNO α-Hydrogen Nitroxyl Radicals(Link)

ChemCatChem
March 12, 2015
α-Hydrogen-substituted nitroxyl radicals are of considerable interest as catalysts for oxidation and polymerization, but are usually inherently unstable. We report herein the catalytic activity of a new family of stable iso-azaphenalene (IAPNO) α-hydrogen nitroxyl radicals in the copper/bipyridine/N-methylimidazole co-catalyzed aerobic oxidation of alcohols. The nitroxyl radical Mes/TIPSO-IAPNO (...more

Oxidative Asymmetric Umpolung Alkylation of Evans’ β-Keto Imides by Dialkylzinc Nucleophiles(Link)

Organic and Biomolecular Chemistry
January 12, 2015
Seleected as a HOT paper:
Umpolung alkylation of Evans’ auxiliary substituted β-ketoimides affords the diastereomerically pure products in yields ranging from 40-80%. The reaction itself proceeds with diastereoselectivities between 3:1 and 18:1. Dialkylzinc serves as the nucleophile and umpolung of the β-keto-imide enolate is achieved by the action of Koser’s reagent.

Oxidative Umpolung α-Alkylation of Ketones(Link)

Organic Letters
January 6, 2015
We disclose a hypervalent iodine mediated α-alkylative umpolung reaction of carbonyl compounds with dialkylzinc as the alkyl source. The reaction is applicable to all common classes of ketones including 1,3-dicarbonyl compounds and regular ketones via their lithium enolates. The α-alkylated carbonyl products are formed in up to 93% yield. An ionic mechanism is inferred based on meticulous analysis...more

Synthetic and Mechanistic Study of the Catalytic Enantioselective Preparation of Primary β-Aminoketones from Enones and a Fluorinated Gabriel Reagent(Link)

ACS Catalysis
November 19, 2014
Salen μ-oxo complex of aluminum catalyzes the asymmetric 1,4-addition of the novel ammonia equivalent 3,4,5,6-tetrafluorophthalimide to unsaturated ketones. All of the reagents are inexpensive and are readily available. The products are formed in up to 89% yield and up to 96% ee. The tetrafluorophthalimide group is removed under mild chemoselective conditions and in high yields to afford the free...more

Probing the Biology of Natural Products: Molecular Editing by Diverted Total Synthesis(Link)

Angewandte Chemie
November 2010
The systematic modification of natural products through diverted total synthesis is a powerful concept for the systematic modification of natural products with the aim of studying mechanistic aspects of their biological activity. This concept offers far-reaching opportunities for discovery at the interface of biology and chemistry. It is underpinned by the power of chemical synthesis, which...more

Alex M. Szpilman
Assistant Professor
Post doc: ETH Zurich, Swiss Federal Institute of Technology with Prof. Erick M. Carreira
Ph.D: Weizmann Institute of Science, 2003, with Prof. Mario D. Bachi
Room Number: 554
Phone: +972-4-829-5953
Fax: +972-4-829-5703
szpilman@tx.technion.ac.il
Group/Personal Website
Research Interests
New Reactions and Methods Asymmetric Synthesis and Catalysis Total Synthesis of Natural Products Cascade reactions for rapid increase in molecular complexity Probing the Molecular Mechanism of Action of Natural Products
Research Abstract
Organic Synthesis is the Art and Science of preparing complex functional  molecules from simple starting materials. Thus, it is a technology that  is essential for a wide range of other fields and of prime importance in  both academia and industry. The primary focus of the Szpilman group is  the development of new ways of forging chemical bonds. Lessons learned  from supra-molecular chemistry, structural biology and chemistry serve  as the inspiration for solving synthetic problems of general importance.
Our research interests include:
a) Designing structurally novel and efficient catalysts for chemical  processes. We are especially interested in developing chiral catalysts  for asymmetric catalysis. Asymmetric catalysis is important e.g. in  drug production.
b) Discovering and inventing, efficient and environmentally friendly  chemical reactions that allow preparing important materials with a  minimum of waste generation and energy consumption.
c) Innovating safe, environmentally friendly ways of storing and  delivering energy.
d) Creative step-economical ways to synthesize natural products. Targets  are chosen, which possess intriguing structures and biological  properties. Bottom up chemical synthesis of biologically active  molecules represents a unique and powerful tool to address biological  mechanisms relevant to medicine.
Selected Publications
  • “Design Concept for α-Hydrogen Substituted Nitroxides” Michal Amar, Sukanta Bar, Mark A. Iron, Hila Toledo, Boris Tumanskii, Linda J. W. Shimon, Mark Botoshansky, Natalia Fridman, and Alex M. Szpilman   Nature Communications,2015, 6, 6070
  • “Oxidative Umpolung α-Alkylation of Ketones” O. Svetlana Shneider, Evgeni Pisarevsky, Peter Fristrup, and Alex M. Szpilman Organic Letters, 2015, 17, 282-285
  • “Synthetic and Mechanistic study of the Catalytic Enantioselective Synthesis of primary β-Amino Ketones from Enones and a Fluorinated Gabriel Reagent”Shlomit Avidan-Shlomovich, Harisadhan Ghosh, and Alex M. Szpilman*  ACS Catalysis, 2015, 5, 336-342
  • “Direct Organocatalytic Oxidation of Aldehydes to Mixed Anhydrides” Hila  Toledo, Evgeni Piseravsky, Adi  Abramovich, and  Alex M. Szpilman , Chem. Commun., 2013, 49, 4367-4369
  • “Probing the Biology of Natural Products: Molecular Editing by Diverted  Total Synthesis”  Alex M. Szpilman and Erick M. Carreira, Angewandte  Chemie International Edition, 2010, 49, 9592–9628
Awards
2010 Chaya Career Advancement Chair
2004 Carlsberg Foundation Postdoctoral Fellowship
2003 Carlsberg Foundation Postdoctoral Fellowship
Group Members
Shlomit Avidan
Irit Cohen
Michal Amar
Orel Svetlana Shneider
Shimon Maximenko
Ravishashidha Vavilala
Sukanta Bar
Tom Targel
Hila Toledo

Group Picture
Szpilman Group March 2013
Postdoctoral Fellows
 
None  
Dr. Jayprakash Kumar,
Schulich Postdoctoral FellowPh.D.: Indian Institute of Chemical
Technology (IICT) Hyderabad		  
 
Graduate Students
 No Picture AvilableNo Picture Avilable
Shlomy Arava, M.Sc.M.Sc.: Bar Ilan University
B.Sc.: Bar Ilan University
Shlomy joined the group for his Ph.D. March 2015		Hila Toledo, M. Sc.M.Sc.: Technion
B.Sc.: Technion
Hila  joined the group in 2010 for her Masters and is now studying towards her Ph.D. 		Shimon Maksymenko, M.Sc.
M.Sc.: Technion
B. Sc.: Technion
Shimon joined the group for his Ph.D. August 2014.



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Ester Segal

Ester Segal

Ester Segal

Associate Professor at Technion - Israel Institute of Technology

Prof. Ester Segal

Email:esegal@tx.technion.ac.ilEster Segal earned her B.Sc. (cum laude) in chemical engineering in 1997 from the Technion – Israel Institute of Technology. Her M.Sc. and Ph.D. in polymer science under Professor Moshe Narkis focused on the development of electrically conductive polymer systems and their application as sensors for volatile organic compounds. After completing her PhD in 2004, she was awarded with the Rothschild Postdoctoral Fellowship and she joined the group of Prof. Mike Sailor at the Department of Chemistry and Biochemistry at the University of California, San Diego, working on porous Si nanomaterials.  In 2007 she returned to Israel and joined the Department of Biotechnology and Food Engineering at the Technion.
At the Technion, she is leading a research group focusing at the broad interface between materials science and biotechnology. Research projects in Prof. Segal’s laboratory implement a multidisciplinary approach coupling materials science and engineering, chemistry and biology for addressing problems in biotechnology, food engineering, and medicine. Current projects include the development of novel nanomaterials for sensing, biosensing, bioassays, and advanced new drug delivery schemes.
LINKS

Experience

Associate Professor

Technion - Israel Institute of Technology
 – Present (3 years)Haifa, Israel

Assistant Professor

Technion - Israel Institute of Technology
 –  (6 years)Haifa, Israel

Postdoc

University of California, San Diego
 –  (3 years)


Has that food in the fridge gone bad?

 BY  
 
 
Ester Segal of Technion explains her team’s creation of a sensor to detect bacteria in food and water. Photos by Suzanne Pollak
ESTER SEGAL OF TECHNION EXPLAINS HER TEAM’S CREATION OF A SENSOR TO DETECT BACTERIA IN FOOD AND WATER.
PHOTOS BY SUZANNE POLLAK
Those expiration dates on the yogurt and salad dressing in the back of the refrigerator may one day be a thing of the past.
A team at Technion- Israel Institute of Technology has a developed an inexpensive and quick way to identify bacteria in food and water, with the invention currently in testing stages.
Ester Segal, associate professor at Technion, spoke Jan. 29 at Ohr Kodesh Congregation in Chevy Chase about her team’s design.
While thinking big, Segal worked on an incredibly small scale. Her team’s invention, called a biosensor, is designed to greatly reduce the amount of contaminated food available for consumption. Work was done using nanotechnology, which means her team’s measurements were done using the nanoscale. A nanometer is equal to one-billionth of a meter.
As any parent who has waited to learn results of a throat culture knows, it can take two days in a lab for bacteria to grow and for health care providers to obtain test results, she said.
But, if the results can be learned instantly, medicine can administered sooner.
Similarly, bacteria-infected food can be removed before it reaches stores.
“The challenge is to ID [the bacteria], ideally in real time and outside the lab [at the site of the contamination],” Segal said during her talk, which was sponsored by the Israel Solidarity Committee of Ohr Kodesh and the Washington Chapter of American Technion.
The biosensor has two elements.
One is a receptor, often an antibiotic, which recognizes bacteria. The other is a transducer, which enables a person using the biosensor to recognize the presence of bacteria. The person reading the results is alerted to bacteria by a light that changes color.
The machine uses a silicon wafer similar to the ones in cellular phones. However, this piece of silicon is perforated so that it has tiny holes throughout, Segal explained.
When water or food is tested, the bacteria present either fall down these holes or stay atop the wafer. Either way, the change disturbs the way light is reflected, sending off a different color.
Segal anticipates that her biosensor one day will be inexpensive enough for people to test the yogurt in their refrigerators, instead of relying on a printed expiration date.
Those dates are “intellectual guesses” and “assumptions,” she said.
She asked the 25 people gathered in the synagogue’s library how often they threw something away even though it had yet to expire or noticed that one piece of food had mold on it while another did not, although they both had the same expiration date.
The biosensor is licensed by Technion and is undergoing testing in a European lab.
A pilot program will be conducted in the Netherlands during this spring’s growing season. This is important, Segal said, because the Netherlands does not allow chlorine in its water, which permits bacteria to grow. Without chlorine, there is a “huge potential” for contamination, Segal said.
If everything is successful, Segal expects the biosensor to be approved for use. She is optimistic the new nanotechnology will greatly reduce the roughly 3,000 deaths and 45 million non-fatal illnesses annually in the United States due to bacteria-contaminated food and water.
Meanwhile, her team is trying to create better food packaging material using essential oils that will lengthen the shelf life of food and prevent bacteria from growing while food is being transported. Currently, plastics are used in a great deal of packaging materials, although fungi and mold grow in that environment, Segal said.
“Fungi and molds are very difficult to kill. You must know that from your shower curtains,” she said.
He team also is looking into detecting bacteria more quickly in illnesses, including urinary tract infections, and being able to determine more readily which antibiotics work on which bacteria.
Segal’s use of nanotechnology to improve food safety has been in the works since 2008.
That includes time spent raising funds and seeking grants, she said, as raising money for her work is part of her job. She said it took her about one year to obtain money from the Israel Science Foundation before she was able to begin her scientific work. As the biosensor progressed, Segal often found herself involved in applying for competitive grants to keep her work on track.

Technion: Prof Ester Segal, multifunctional nanoparticles, winner of Yanai Prize

Prof Ester Segal, Technion, nanomedicine, nanotechnologyProf Ester Segal, Technion, nanomedicine, nanotechnology
On March, 12 2015 by Israël Science Info Desk
“Teaching is very demanding, and it’s not always easy finding the time to devote to it with all the other tasks before me, but for me it is a true calling,” explains Prof. Ester Segal from the Faculty of Biotechnology & Food Engineering. Prof. Segal was recently awarded the Yanai Prize for Excellence along with nine other faculty members. The prize, funded by Technion graduate Mr. Moshe Yanai in the amount of 100 thousand Shekels, is awarded to Technion faculty.
In her acceptance speech at the prize ceremony, Prof. Segal explained that, “The role of teacher for me is not only about the transfer of knowledge, imparting skills and assisting students in achieving the highest possible grades. It is our task to instil curiosity and a desire for knowledge, to nurture critical thinking, creativity and independence, and to prepare students for the real world that will be waiting for upon completing their studies. I believe that as educators, we should approach teaching with the same enthusiasm and responsibility we place on research on our research. Such attitude towards teaching makes it an interesting and challenging activity and motivates us to be innovative and effective in the classroom. We must keep in mind that in teaching, there is no ‘one size fits all’ – classes are always heterogeneous, and each student has a different learning style. I also believe that building communication and trust is critical for establishing an efficient and productive learning environment. I show the students empathy and care; this also means going an extra mile for them.”
Prof. Ester Segal completed all three of her degrees at the Technion’s Faculty of Chemical Engineering. In 2007, upon completion of her postdoctorate at the Faculty of Chemistry and Biochemistry at the University of California, San Diego (UCSD), she joined the Faculty of Biotechnology and Food Engineering at the Technion. She currently heads the Multifunctional Nanomaterials Laboratory, located at the Faculty, and in the past year she received the Henry Taub Prize for Excellence in Research.
The image illustrates porous silicon (PSi) particles used as a platform for the delivery of anticancer drugs (highlighted in green on the diagram) and its release at the targeted breast cancer tumors. The degradation of the PSi at the tumor microenvironment was investigated using novel imaging methods. The researchers tracked the decomposition of the material on the diseased tissue and uncovered its degradation mechanism, which triggers the release of the drugs trapped within the porous medium
The image illustrates porous silicon (PSi) particles used as a platform for the delivery of anticancer drugs (highlighted in green on the diagram) and its release at the targeted breast cancer tumors. The degradation of the PSi at the tumor microenvironment was investigated using novel imaging methods. The researchers tracked the decomposition of the material on the diseased tissue and uncovered its degradation mechanism, which triggers the release of the drugs trapped within the porous medium.
Prof. Segal heads a multidisciplinary research team investigating the interface between materials science and biotechnology. The main research at the laboratory focuses on the synthesis and characterization of nanomaterials and their application to the development of biological sensors and drug delivery systems.
In an article she recently published in the prestigious journal Nature Communications, she reported that silicon carriers for the local delivery of anticancer drugs degrade differently when they reach the diseased environment, which can affect clinical outcomes. The study, conducted jointly with Prof. Natalie Artzi from the Massachusetts Institute of Technology (MIT) and the Harvard Medical School, sheds light on this degradation process, opening the way for improved tumor treatments.
“In this study we have shown for the first time that biomaterials in general, and nanostructured porous silicon in particular, behave differently when they are injected (or implanted) at the tumor microenvironment. Over the last few years, we successfully engineered silicon to be used as a carrier of anticancer drugs that releases its contents in a controlled manner, and now we are focusing on the degradation mechanism of the silicon at the diseased tissue,” explains Prof. Segal.
Nanostructured Porous Silicon is the common name for a family of silicon-based materials containing nano-scale holes. This material is today seen as a promising drug delivery vehicle, mainly due to its unique characteristics: a large surface area (geared for drug unloading), biocompatbility, and bio-degradability in a safe and non-toxic manner. In recent years, Prof. Segal and her doctoral student Adi Tzur-Balter developed ‘containers’ (carriers) for the delivery of anticancer drugs. Through careful design of the silicon containers, in terms of their pore diameter and surface chemistry, the group achieved optimal features for effective drug delivery.
One of the important findings of the study, which investigates the behavior of the silicon ‘containers in breast cancer tumors, is associated with the accelerated degradation of the silicon material in the diseased area. The research showed that reactive oxygen species upregulated in the cancerous environment (in vivo), induce oxidation of the silicon, causing a rapid degradation of the ‘containers’ as compared with (in vitro) lab experiments. As a result, this article sheds light on the process of nanostructured silicon degradation at the tumor microenvironment, and allows for early and smart design intervention of the silicon structure to facilitate controlled release of the drug at the targeted site.


Prof. Ester Segal receives the Henry Taub Award for Academic Excellence

27 March, 2014
Ester will receive the prestigious prize during the upcoming annual meeting of Technion’s Board of Governors.

Webinars with Ester Segal

On this page, conducts webinars wonderful famous Esther Segal .Arhiv webinars updated as of meropriyatiy.Priyatnogo view.


Ester Segal

THE TECHNION INTEGRATED CANCER CENTER

The Technion Integrated Cancer Center (TICC) combines scientists from the university’s strong basic science and engineering departments with its researchers from its Faculty of Medicine and clinicians from the Rambam Health Care Campus. This multidisciplinary approach will help move scientific discoveries into medical applications. Nearly 600,000 people in the U.S. die of cancer yearly, and the Technion’s unique approach has led to life-saving cancer drugs and inroads into cancer diagnosis, drug delivery and other breakthroughs.



Nanomedicine: Can Cancer Tumor Control The Release Of Therapeutics?

Silicon carriers for local delivery of anticancer drugs degrade differently when reaching the diseased environment, affecting clinical outcome. A joint study conducted at Technion, MIT and Harvard sheds light on this degradation process, paving the way for improving tumor treatments of this kind  
 
Prof. Segal Technion

The prestigious journal Nature Communications reveals that silicon nanomaterials for localized delivery chemotherapeutics behaves differently in cancerous tumors in comparison to healthy tissues. The joint study was conducted at the Technion, Massachusetts Institute of Technology (MIT) and the Harvard Medical School. Professor Ester Segal, who heads the Technion group that led the study, explains, “We have shown for the first time that biomaterials in general, and nanostructured porous silicon in particular, behave differently when they are injected (or implanted) at the tumor microenvironment. Over the last few years we successfully engineered silicon to be used as a carrier of anticancer drugs that releases its contents in a controlled manner, and now we have focused on the degradation mechanism of the silicon at the diseased tissue.”

Nanostructured Porous Silicon is the common name for a family of silicon-based materials containing nano-scale holes. This material is known today as a promising drug delivery vehicle, mainly due to its unique characteristics: a large surface area (geared for drug unloading), biocompatbility, and bio-degradability in a safe and non-toxic manner. In recent years, Prof. Segal and her doctoral student Adi Tzur-Balter developed ‘containers’ (carriers) for the delivery of anticancer drugs. Through careful design of the silicon containers, in terms of their pore diameter and surface chemistry, the group achieved optimal features for effective drug delivery.

The important findings of the study, which investigated the behavior of the silicon ‘containers’ in breast cancer tumors, is associated with the accelarated degradation of the silicon material in the diseased area. The resaerch showed that reactive oxygen scecies upregulated in the cancerous environment (in vivo), induce oxidation of the silicon, causing a rapid degradation of the ‘containers’ as compared with (in vitro) lab experiments. As a result, this article sheds light on the process of nanostructured silicon degradation at the tumor microenvironment, and allows for early and smart design intervention of the silicon structure to facilitate controlled release of the drug atthe targeted site. Importantly, the ability to determine and predict material fate in vivounder specific environments is the next step in biomaterial design that would lead to faster and successful clinical translation.


The image illustrates porous silicon (PSi) particles used as a platform for the delivery of anticancer drugs (highlighted in green on the diagram) and its release at the targeted breast cancer tumors. The degradation of the PSi at the tumor microenvironment was investigated using novel imaging methods. The researchers tracked the decomposition of the material on the diseased tissue and uncovered its degradation mechanism, which triggers the release of the drugs trapped within the porous medium.


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