Bioabsorbable Magnesium Cardiovascular Stents

Overview

While stents are a lifesaving technology, they pose risks to patients when they remain in their arteries for long periods. Biodegradable stents are a promising alternative to permanent stents and can provide a solution to the problem of in-stent restenosis. The objective of this project is to develop nanostructured variants of several magnesium alloys that can be used to make cardiovascular stents which dissolve after they have served their primary function of restoring blood circulation in occluded arteries. Magnesium is an excellent candidate bioresorbable material for fabricating stents, but lacks the strength, ductility, and corrosion resistance needed for expandable stents. However, by nanostructuring we can enhance the mechanical properties and tailor absorbability.

Project Description

Multi-stage ECAP-C processing schemes are being developed that incorporate variable temperature and strain rates to refine grain size, increase stored dislocation density, and shear precipitates to alter their effects on bioabsorption rates. In addition, we control process conditions to alter the propensity for twin formation during and after processing to enhance the isotropy of the resulting ultrafine grained magnesium alloys.

Status

The project has demonstrated that a microalloyed, thixomolded Mg alloy can be modified by HSD to achieve 500 nm grain sizes, increases in ductility, controllable bioabsorption rates, and isotropic strength levels sufficient to enable implementation of the nanostructured alloy in bioabsorbable coronary stents. Prototype stents have been fabricated and tested in bench tests and animal studies. Scale up of the technology is pending market assessment by the sponsor and partner organizations.
Meanwhile, additional Mg alloys are being proposed for ECAP-C processing to create ultrafine grain variants suitable for dissolvable trauma screws and devices.

Key Convergences in this Project

Materials Science, Mechanical Metallurgy, Corrosion Engineering, Biomedical Engineering

With placement outcomes within three months of graduation exceeding 80 percent for the last five years and average starting salaries over $69,000, our graduates continue to be in high demand for industry, government, military and graduate school positions across the country.

Additional Program Information

Accreditation

Both degrees leading to the Bachelor of Science are accredited by the Engineering Accreditation Commission of the Accreditation Board for Engineering and Technology (ABET), 111 Market Place, Suite 1050, Baltimore, MD 21202-4012, (410) 347-7700. ABET, the recognized accreditor for college and university programs in applied science, computing, engineering, and technology, is a federation of 28 professional and technical societies representing these fields.

The Chemical and Biological Engineering Department at Mines has two undergraduate degree programs: 1) BS Chemical Engineering and 2) BS Chemical and Biochemical Engineering. Both degree programs are ABET-accredited through 2018.

To be accredited, a program must have educational objectives and associated student outcomes that lead to meeting those objectives. Programs must also have a comprehensive assessment methodology in place that provides continuous feedback and demonstrates that the objectives are being met.

For both degree programs. our objectives for our graduates within three to five years of completing their degree are that they will:

  1. be in graduate school or in the workforce utilizing their education in chemical engineering fundamentals; and
  2. be applying their knowledge of and skills in engineering fundamentals in conventional areas of chemical engineering and in contemporary and growing fields; and
  3. have demonstrated both their commitment to continuing to develop personally and professionally, and an appreciation for the ethical and social responsibilities associated with being an engineer and a world citizen.

In addition to the above objectives, our Chemical and Biochemical Engineering graduates three to five years out will:

  1. be applying their knowledge of and skills in biochemical engineering fundamentals.
Combined Baccalaureate / Master's Degree Program

The Chemical and Biological Engineering Department offers the opportunity to begin work on a master of science (with thesis) degree while completing the requirements of the bachelor’s degree. These combined BS/MS programs are designed to allow undergraduates engaged in research to apply their experience to an advanced degree. An advantage of the combined BS/MS program is that students may apply two classes (6 credit hours) to both their BS and MS degrees. These two classes must be chemical engineering elective courses at the 400-level or higher. The remaining MS curriculum consists of the four core graduate courses (CHEN507, CHEN509, CHEN516 and CHEN518) and 18 thesis credits. It is expected that a student would be able to complete both degrees in five to five and a half years. To take advantage of the combined program, students should be engaged in research and taking graduate coursework during their senior year. For this reason, students are expected to apply to the program by the end of their junior year. Students must have a GPA greater than 3.0 to be considered for the program. Interested students are encouraged to get more information from their advisor or the faculty member in charge of graduate affairs.

Advising Sheet: Chemical Engineering

Freshman Year, Fall Semester

Course No. Title Hours
CHGN 121 Principles of Chemistry 4
CSM 101 Freshman Success Seminar 0.5
EPIC 151 Design I 3
CBEN 110 Fundamentals of Biology I 4
MATH 111 Calculus for Scientists and Engineers I 4
PAGN XXX Physical Education I 0.5
TOTAL 16

Freshman Year, Spring Semester

Course No. Title Hours
LAIS 100 Nature and Human Values 4
CHGN 122 Principles of Chemistry 4
MATH 112 Calculus for Scientists and Engineers II 4
PAGN XXX Physical Education II 0.5
PHGN 100 Physics I 4.5
TOTAL 17

Sophomore Year, Fall Semester

Course No. Title Hours
CBEN 210 Introduction to Thermodynamics 3
CHGN 221 Organic Chemistry I 3
CHGN 223 Organic Chemistry I Lab (or in spring) 1
MATH 213 Calculus for Scientists and Engineers III 4
PAGN XXX Physical Education III .5
PHGN 200 Physics II 4.5
TOTAL 16

Sophomore Year, Spring Semester

Course No. Title Hours
CBEN 201 Mass and Energy Balances 3
CBEN 202 Chemical Process Principles Lab 1
CHGN 222 Organic Chemistry II 3
EBGN 201 Principles of EconomicsI 3
EPIC 265 Biochemical Processes Design II 3
MATH 225 Differential Equations 3
PAGN XXX Physical Education IV 0.5
TOTAL 16.5

Junior Year, Fall Semester

Course No. Title Hours
CBEN 307 Fluid Mechanics 3
CBEN 357 Chemical Engineering Thermodynamics 3
CHGN 351 Physical Chemistry I 3
LAIS 200 Human Systems 3
Free Elective 1 3
TOTAL 15

Summer Field Session

CBEN 312/313 Unit Operations Lab 6

Junior Year, Spring Semester

Course No. Title Hours
CBEN 308 Chemical Engineering Heat Transfer 3
CBEN 358 Chemical Engineering Thermodynamics Lab 1
CBEN 375 Chemical Engineering Mass Transfer 3
CBEN or CHGN Elective (at least 300 level) 3
LAIS / EBGN Elective 1 3
Free Elective 2 3
TOTAL 16

Senior Year, Fall Semester

Course No. Title Hours
CBEN 418 Reaction Engineering 3
CBEN 430 Transport Phenomena 3
CBEN* Elective I 3
LAIS / EBGN Elective 2 3
Free Elective 3 4
TOTAL 16

Senior Year, Spring Semester

Course No. Title Hours
CBEN 402 Chemical Engineering Design 3
CBEN 403 Process Dynamics and Control 3
EBGN 321 Engineering Economics 3
CBEN* Elective 2 (400 level) 3
LAIS / EBGN Elective 3 (400 level) 3
TOTAL 15

*Not all CBEN courses count as CBEN electives.

Advising Sheet: Chemical and Biochemical Engineering

Freshman Year, Fall Semester

Course No. Title Hours
CHGN 121 Principles of Chemistry 4
CSM 101 Freshman Success Seminar 0.5
EPIC 151 Design I 3
CBEN 110 Fundamentals of Biology I 4
MATH 111 Calculus for Scientists and Engineers I 4
PAGN XXX Physical Education I 0.5
TOTAL 16

Freshman Year, Spring Semester

Course No. Title Hours
LAIS 100 Nature and Human Values 4
CHGN 122 Principles of Chemistry 4
MATH 112 Calculus for Scientists and Engineers II 4
PAGN XXX Physical Education II 0.5
PHGN 100 Physics I 4.5
TOTAL 17

Sophomore Year, Fall Semester

Course No. Title Hours
CBEN 210 Introduction to Thermodynamics 3
CHGN 221 Organic Chemistry I 3
CHGN 223 Organic Chemistry I Lab (or in spring) 1
MATH 213 Calculus for Scientists and Engineers III 4
PAGN XXX Physical Education III .5
PHGN 200 Physics II 4.5
TOTAL 16

Sophomore Year, Spring Semester

Course No. Title Hours
CBEN 201 Mass and Energy Balances 3
CBEN 202 Chemical Process Principles Lab 1
CHGN 222 Organic Chemistry II 3
EBGN 201 Principles of EconomicsI 3
EPIC 265 Biochemical Processes Design II 3
MATH 225 Differential Equations 3
PAGN XXX Physical Education IV 0.5
TOTAL 16.5

Junior Year, Fall Semester

Course No. Title Hours
CBEN 307 Fluid Mechanics 3
CBEN 357 Chemical Engineering Thermodynamics 3
CHGN 428 Intro to Biochemistry 3
LAIS 200 Human Systems 3
Free Elective 1 3
TOTAL 15

Summer Field Session

CBEN 312/313 Unit Operations Lab 6

Junior Year, Spring Semester

Course No. Title Hours
CBEN 308 Chemical Engineering Heat Transfer 3
CBEN 358 Chemical Engineering Thermodynamics Lab 1
CBEN 375 Chemical Engineering Mass Transfer 3
CHGN 351 Physical Chemistry I 4
CHGN 462 Microbiology 3
LAIS / EBGN Elective 1 3
TOTAL 17

Senior Year, Fall Semester

Course No. Title Hours
CBEN 418 Reaction Engineering 3
CBEN 430 Transport Phenomena 3
CBEN 460 Bioprocess Engineering 3
CBEN 461 Bioprocess Engineering Laboratory 1
LAIS / EBGN Elective 2 3
Free Elective 2 3
TOTAL 16

Senior Year, Spring Semester

Course No. Title Hours
CBEN 402 Chemical Engineering Design 3
CBEN 403 Process Dynamics and Control 3
EBGN 321 Engineering Economics 3
LAIS / EBGN Elective 3 (400 level) 3
Free Elective 3 3
TOTAL 15
Chemical and Biological Engineering Electives

NOTE: Any CHGN or CBEN 3XX course counts as the CHGN or CBEN 3XX elective listed in the spring semester of the junior year. However, only CBEN courses with engineering content count as the CBEN electives listed in the senior year. Those courses include the following:

Course No. Title Credit Hours
CBEN 200 Computational Methods in Chemical Engineering 3
CBEN 250 Introduction to Chemical Engineering Analysis and Design 3
CBEN 310 Introduction to Biomedical Engineering 3
CBEN 315 Introduction to Electrochemical Engineering 3
CBEN 340 Cooperative Education 1-3
CBEN 35X, 45X, X98, X99 Honors UG Research, Special Topics, Independent Study* 1-6
CBEN 368 Introduction to Undergraduate Research 1
CBEN 401 Introduction to Chemical Process Design 3
CBEN 408 Natural Gas Processing 3
CBEN 409 Petroleum Processes 3
CBEN 415 Polymer Science and Technology 3
CBEN 416 Polymer Engineering and Technology 3
CBEN 420 Mathematical Methods in Chemical Engineering 3
CBEN 432 Transport Phenomena in Biological Systems 3
CBEN 435 Interdisciplinary Microelectronics 3
CBEN 440 Molecular Perspectives in Chemical Engineering 3
CBEN 460 Biochemical Process Engineering 3
CBEN 461 Biochemical Process Engineering 1
CBEN 469 Fuel Cell Science and Technology 3
CBEN 470 Introduction to Microfluidics 3
CBEN 472 Introduction to Energy Technologies 3
CBEN 480 Natural Gas Hydrates 3

*If content has sufficient engineering basis, as determined by the department head given the project description, these courses can count as a CBEN elective.

The following CBEN bio-related courses DO NOT have sufficient engineering content and therefore DO NOT count as CBEN electives.

Course No. Title Credit Hours
CBEN 110 (BIOL 110) Fundamentals of Biology I 4
CBEN 303/323/120 Fundamentals of Biology II 4
CBEN 304/305 Anatomy and Physiology 3
CBEN 306/309 Anatomy and Physiology: Bone, Muscle and Brain 3
CBEN 311 Introduction to Neuroscience 3
CBEN 320 Cell Biology and Physiology 3
CBEN 321 Introduction to Genetics 4
CBEN 411 Neuroscience, Memory and Learning 3
CBEN 412 Introduction to Pharmacology 3
CBEN 431 Immunology 3
CBEN 454 Applied Bioinformatics 3
Biomedical Engineering Minor

To obtain a Biomedical Engineering minor, students must take at least 18 credits related to Biomedical Engineering. Two courses (8 credits) of biology are required. Two restricted requirements include Intro to Biomedical Engineering (required) and at least 3 credits of engineering electives related to BME. Two more courses (or at least 4 credits) may be chosen from the engineering and/or additional electives. The lists of electives will be modified as new related courses that fall into these categories become available.

Required Courses (11 credits)

CBEN 110 Fundamentals of Biology I 4
CBEN 120 Studio Biology II 4
CBEN 310 Intro to Biomedical Engineering 3

Engineering Elective Courses Related to BME
(at least 3 credits)

CBEN 432 Transport Phenomena in Biological Systems 3
CBEN 470 Introduction to Microfluidics 3
CBEN 35x, 45x, x98, x99 Honors Undergraduate Research, Special Topics 1 – 3
MEGN 330 Introduction to Biomechanical Engineering 3
MEGN 430 Musculoskeletal Biomechanics 3
MEGN 435/535 Modeling and Simulation of Human Movement 3
MEGN 436/536 Computational Biomechanics 3
MEGN 530 Biomedical Instrumentations 3
MEGN 531 Prosthetic and Implant Engineering 3
MEGN 532 Experimental Methods in Biomech 3
MEGN 537 Probabilistic Biomechanics 3
MTGN 570 Intro to Biocompatibility 3

Additional Elective Courses Related to BME
(two courses or at least 4 credits from the list above or below)

CBEN 311 Introduction to Neuroscience 3
CBEN 322 Biology of Behavior 3
CBEN 398 Anatomy 3
CBEN 398 Anatomy Lab 1
CBEN 398 Physiology 3
CBEN 320 (410) Cell Biology and Physiology 3
CBEN 321 Intro to Genetics (+ Lab) 4
CBEN 411 Neuroscience, Memory, and Learning 3
CBEN 431/531 Immunology for Engineers and Scientists 3
CBEN 454/554 Applied Bioinformatics 3
CBEN 35x, 45x, x98, x99 Honors Undergraduate Research, Special Topics 1-3
CHGN428 Introductory Biochemistry 3
CHGN429 Intro to Biochemistry II 3
CHGN 462 Microbiology 3
MATH 331 Mathematical Biology 3
MTGN 472/572 Biomaterials I 3
PHGN 433 Introduction to Biophysics 3