Buddy D Ratner

Buddy D Ratner
University of Washington Seattle | UW · Department of Bioengineering

Ph.D.

About

458
Publications
36,406
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33,398
Citations
Citations since 2017
13 Research Items
8404 Citations
201720182019202020212022202305001,0001,500
201720182019202020212022202305001,0001,500
201720182019202020212022202305001,0001,500
201720182019202020212022202305001,0001,500

Publications

Publications (458)
Article
Portable Dialysis In article number 2102308, Guozheng Shao, Bruce J. Hinds, and co‐workers report a portable dialysis device for end‐stage renal disease (ESRD) patients enabled by a two‐stage dialyzer system coupled with a photooxidation urea removal (POUR) unit. Working together with the hemodialyzer, the forward osmosis cartridge selectively remo...
Article
Portable dialysis can meaningfully improve the health outcomes and life quality of end‐stage renal disease (ESRD) patients and reduce the economic burdens of dialysis related care. Current treatment sessions use 120 Kg of aqueous dialysate, thus key to realizing portability is the continuous regeneration of small volumes of spent dialysate. Urea is...
Article
Unmet needs for small diameter, non-biologic vascular grafts and the less-than-ideal performance of medium diameter grafts suggest opportunities for major improvements. Biomaterials that are mechanically matched to native blood vessels, reduce the foreign body capsule (FBC) and demonstrate improved integration and healing are expected to improve gr...
Article
Protein and cell interactions on implanted, blood-contacting medical device surfaces can lead to adverse biological reactions. Medical-grade poly(vinyl chloride) (PVC) materials have been used for decades, particularly as blood-contacting tubes and containers. However, there are numerous concerns with their performance including platelet activation...
Chapter
This chapter outlines methods and concerns in evaluating the blood compatibility of biomaterials and medical devices. It does not automatically follow that if the materials comprising a device are blood compatible, then a device fabricated from those materials will also be blood compatible. The interplay between the biomaterial, flow conditions, an...
Chapter
This chapter provide a brief overview of the development of the field of biomaterials from the days of adventurous practices by surgeon-heroes, to the many accidental discovery and development of unexpected biomaterials, and to the modern era where engineers, chemists, physicists, biologists and clinicians work together to engineer novel medical tr...
Chapter
Biomaterials Science: An Introduction to Materials in Medicine directly addresses the multidisciplinary nature of the biomaterials field by providing concise tutorials in the key concepts essential for practitioners of biomaterials science. The word “biomaterials” implies an intersection of biology and materials. This Section 2.1 addresses the fund...
Chapter
While many different surface compositions have non-fouling properties, one major factor favoring resistance to protein adsorption is the retention of bound water molecules by surface molecules. A better understanding of how to optimize the surface density and composition of non-fouling surfaces will lead to improvements in surface quality with fewe...
Chapter
The surface of a biomaterial typically represents a very small fraction of a biomaterial, but the surface structure and composition usually differ from the bulk. Since the surface region of a biomaterial is what interacts with the biological environment, characterization of its structure and composition is essential. Specialized techniques are requ...
Chapter
This chapter clarifies some of the issues in biocompatibility, and also raises questions that will likely impact the field in the coming years. In contrast to empirical approaches and practical considerations focused solely about the safety of implanted devices (for example, toxicology, the state of the art today), modern cell and molecular biology...
Chapter
Much effort goes into the design, synthesis, and fabrication of biomaterials and devices to ensure that they have the appropriate mechanical properties, durability, and functionality. The bulk composition and organization of materials govern these properties. Surface modifications are widely applied to modulate or enhance the biointeractions of bio...
Chapter
This chapter first introduces the physical and chemical properties of water, and then expands upon water’s significance for biomaterials and biology. This chapter encourages you to think about how the phenomena you are reading about may be driven or controlled by the water that comprises such a large fraction of all biological systems.
Article
Statement of significance: We report here on the use of a highly sensitive analytical technique, time of flight secondary ion mass spectroscopy (ToF-SIMS) to characterize detergent decellularized scaffolds. ToF-SIMS detected cellular remnants and residual detergent fragments; increased intensity of the detergent fragments correlated with adverse c...
Article
Full-text available
The grim prognosis for patients diagnosed with malignant gliomas necessitates the development of new therapeutic strategies for localized and sustained drug delivery to combat tumor drug resistance and regrowth. Here we introduce drug encapsulated aerosolized microspheres as a biodegradable , intelligent glioma therapy (DREAM BIG therapy). DREAM BI...
Article
The grim prognosis for patients diagnosed with malignant gliomas necessitates the development of new therapeutic strategies for localized and sustained drug delivery to combat tumor drug resistance and regrowth. Here we introduce drug encapsulated aerosolized microspheres as a biodegradable, intelligent glioma therapy (DREAM BIG therapy). DREAM BIG...
Article
Combat-related penetrating ocular injuries have become a common form of battlefield injury in modern warfare and can lead to potentially devastating visual impairments. Prompt stabilization of the wounded globe via prevention of infection and fibrosis enhances the probability of successful outcome after professional medical treatment. In this study...
Article
Full-text available
Revealing cytokine-induced changes in the extracellular matrix with secondary ion mass spectrometry, Acta Biomaterialia (2014), doi: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typese...
Article
Disease or inflammation can have substantial impact on biomaterials performance and the loosely defined term "biocompatibility" (Oliva et al., this issue). Copyright © 2015, American Association for the Advancement of Science.
Article
Background: Circulating tumor cells are found in approximately 70% of men with prostate cancer at the time of primary treatment. Less than a third of these men will develop recurrent cancer within 20 years of primary treatment, suggesting that only a subset of dormant tumor cells are able to escape dormancy and develop into clinical metastases. Esc...
Article
Appropriate mechanical properties and highly interconnected porosity are important properties for tissue engineering scaffolds. However, most existing hydrogel scaffolds suffer from poor mechanical properties limiting their application. Furthermore, it is relatively infrequent that precision control is achieved over pore size and structure of the s...
Article
Synthetic biomaterial scaffolds show promise for in vitro and in vivo 3D cancer models. Tumors engineered in biomaterial scaffolds have shown evidence of being more physiologically relevant than some traditional preclinical model systems, and synthetic biomaterials provide the added benefit of defined and consistent microenvironmental control. Here...
Article
Full-text available
Hydrogels, such as crosslinked poly(2-hydroxyethyl methacrylate) (pHEMA) have been used extensively in controlled release drug delivery systems. Our previous work demonstrated an ultrasound (US)-responsive system based on pHEMA coated with a self-assembled multilayer of C12-C18 methylene chains. The resulting coating was predominantly crystalline a...
Article
Full-text available
For cell-based treatments of myocardial infarction, a better understanding of key developmental signaling pathways and more robust techniques for producing cardiomyocytes are required. Manipulation of Notch signaling has promise as it plays an important role during cardiovascular development, but previous studies presented conflicting results that...
Chapter
This chapter will familiarize the reader with the more common microscopy tools used in current biomaterials research. The key concepts of magnification, resolution, and contrast are first introduced and then their meaning explored in the context of light microscopy. Digital imaging is very briefly addressed. Attention then moves to the electron mic...
Article
The foreign body reaction (FBR) to implanted materials is of critical importance when medical devices require biological integration and vascularization to support their proper function (e.g., transcutaneous devices, implanted drug delivery systems, tissue replacements, and sensors). One class of materials that improves FBR outcomes is made by sphe...
Article
Starting with the observations that fetuses effortlessly grow limbs, fetuses heal wounds without scar and children up to the age of two can partially regrow amputated digits, the potential for adult humans to regrow limbs is explored. The process of limb growth in amphibians is reviewed with these steps summarizing the process: blood vessels contra...
Article
Full-text available
This Master thesis provides a proof of concept for a novel, implantable continuous glucose sensing technology. Immobilized glucose oxidase in a poly 2-hydroxyethyl methacrylate hydrogel is used to enzymatically convert an increase in glucose level to a local decrease in pH, which leads to a swelling of the hydrogel. Encapsulated gold nanoparticles...
Chapter
Peripheral arterial disease (PAD) is the atherosclerotic arterial occlusive disease of the legs that leads to muscle ischemia, disability, and limb loss. Therapeutic approaches that can restore circulation to ischemic limbs are needed. Here we explore the potential of a sphere-templated hydrogel scaffold with 30 micron diameter interconnected pores...
Article
Osteochondral tissue engineering poses the challenge of combining both cartilage and bone tissue engineering fundamentals. In this study, a sphere-templating technique was applied to fabricate an integrated bi-layered scaffold based on degradable poly(hydroxyethyl methacrylate) hydrogel. One layer of the integrated scaffold was designed with a sing...
Article
The performance of implantable biomedical devices is impeded by the foreign-body reaction, which results in formation of a dense collagenous capsule that blocks mass transport and/or electric communication between the implant and the body. No known materials or coatings can completely prevent capsule formation. Here we demonstrate that ultra-low-fo...
Article
Biodegradable poly(N-isopropyl acrylamide) (polyNIPAM) hydrogels with controlled molecular weight of the parent polymer and its degradation products were synthesized by atom transfer radical polymerization in the presence of a polycaprolactone-based di-chlorinated macroinitiator and polycaprolactone dimethacrylate. The phase transition temperature,...
Article
Biomaterials-based tissue engineered tumor models are now widely used in cancer biology studies. However, specific methods for efficient and reliable cell seeding into these and tissue engineering constructs used for regenerative medicine often remain poorly defined. Here, we describe a capillary force-based method for seeding the human prostate ca...
Article
Objective: To evaluate the performance of a sphere-templated poly(2-hydroxyethyl methacrylate) (poly[HEMA]) tissue scaffold as a subcutaneous implant by comparing it with widely used high-density porous polyethylene (HDPPE) implant material. Design: We implanted sphere-templated porous poly-(HEMA) and HDPPE disks into the dorsal subcutis of C57B...
Article
Myocardial infarction (MI) causes significant cell loss and damage to myocardium. Cell-based therapies for treatment of MI aim to remuscularize the resultant scar tissue, but the majority of transplanted cells do not survive or integrate with the host tissue. Scaffolds can improve cell retention following construct implantation, but often do little...
Conference Paper
The American Cancer Society 2012 estimate is that 22,910 malignant tumors of the brain or spinal cord will be diagnosed in the United Sates. Approximately 59.8% will be fatal. Despite current treatments, survival remains low with a median survival of approximately one year despite maximal therapy. Complete tumor removal cannot always be achieved be...
Article
OBJECTIVE To evaluate the performance of a sphere-templated poly(2-hydroxyethyl methacrylate) (poly[HEMA]) tissue scaffold as a subcutaneous implant by comparing it with widely used high-density porous polyethylene (HDPPE) implant material. DESIGN We implanted sphere-templated porous poly-(HEMA) and HDPPE disks into the dorsal subcutis of C57BL/6 m...
Article
This article focuses on one of the major failure routes of implanted medical devices, the foreign body reaction (FBR)--that is, the phagocytic attack and encapsulation by the body of the so-called "biocompatible" biomaterials comprising the devices. We then review strategies currently under development that might lead to biomaterial constructs that...
Article
Albumin-scavenging surfaces decorated with n-alkyl chains represent an established strategy for blood-contacting applications. To evaluate this concept, a set of poly (2-hydroxyethyl methacrylate) (pHEMA) films modified with different amounts of octadecyl isocyanate (C18) was investigated in an in vitro hemocompatibility assay using freshly drawn h...
Article
Tumor dormancy and escape from dormancy remains an elusive mystery in cancer progression; clinically, escape from dormancy is thought to result in recurrent, aggressive disease. Over 70% of prostate cancer patients have disseminated tumor cells (DTCs) in their bone marrow at the time of primary treatment, yet less than 30% of those patients develop...
Article
This study investigates mouse cutaneous responses to long-term percutaneously implanted rods surrounded by sphere-templated porous biomaterials engineered to mimic medical devices surrounded by a porous cuff. We hypothesized that keratinocytes would migrate through the pores and stop, permigrate, or marsupialize along the porous/solid interface. Po...
Article
The host response to biomaterials has been studied for decades. Largely, the interaction of host immune cells, macrophages in particular, with implanted materials has been considered to be a precursor to granulation tissue formation, the classic foreign body reaction, and eventual encapsulation with associated negative impacts upon device functiona...
Article
This article reports the fabrication and characterization of NPs based on the self-assembling of polymeric drugs with amphiphilic character synthetized from oleyl 2-acetamido-2-deoxy-α-d-glucopyranoside methacrylate and vinyl pyrrolidone (OAGMA-VP). NPs were spherical, with an apparent hydrodynamic diameter between 91 and 226 nm and with zeta poten...
Article
Analysis and detection of micronutrients is important for the reduction of the global burden of malnutrition-related disease. A relatively new technique, plasma pencil atmospheric mass spectrometry (PPAMS) was applied in a comprehensive evaluation for rapid, simultaneous detection of the key micronutrients zinc, iron, folate, vitamin A, and iodine....
Book
The revised edition of this renowned and bestselling title is the most comprehensive single text on all aspects of biomaterials science. It provides a balanced, insightful approach to both the learning of the science and technology of biomaterials, and acts as the key reference for practitioners who are involved in the applications of materials in...
Article
Tissue engineering approaches fabricate and subsequently implant cell-seeded and unseeded scaffold biomaterials. Once in the body, these biomaterials are repopulated with somatic cells of various phenotypes whose identification upon explantation can be expensive and time-consuming. We show that imaging time-of-flight secondary ion mass spectrometry...
Article
The sinus between skin and a percutaneous medical device is often a portal for infection. Epidermal integration into an optimized porous biomaterial could seal this sinus. In this study, we measured epithelial ingrowth into rods of sphere-templated porous poly(2-hydroxyethyl methacrylate) implanted percutaneously in mice. The rods contained spheric...
Article
This study reports the use of tetraethylene glycol-terminated self-assembled monolayers (EG(4) SAMs) as a background non-fouling surface to study the effect of an 18 carbon ligand (C18) on albumin selective and reversible adsorption and subsequent platelet and leukocyte adhesion. Surface characterization techniques revealed an efficient immobilizat...
Article
Full-text available
A number of papers appeared in the 1940s, 1950s, and 1960s examining the tissue reaction to implanted biomaterials (for example, see [1]). Though many of these early observations were accurate, the word “biocompatible” was never used. By 1970, a few papers appeared that used the word “biocompatible.” According to the biocompatibility article in Wik...
Article
An ideal surface for implantable glucose sensors would be able to evade the events leading to chronic inflammation and fibrosis, thereby extending its utility in an in vivo environment. Nafion™, a perfluorinated ionomer, is the membrane material preferred for in situ glucose sensors. Unfortunately, the surface properties of Nafion™ promote random p...
Article
Nano-sized hafnium oxide (HfO(2)) particles are being considered for applications within the semiconductor industry. However, little is known about their cytotoxicity. The objective of this work was to assess several HfO(2) nanoparticles (NPs) samples for their acute cytotoxicity. Dynamic light scattering analysis of the samples indicated that the...
Article
Full-text available
Electrospinning from a melt, in contrast to from a solution, is an attractive tissue engineering scaffold manufacturing process as it allows for the formation of small diameter fibers while eliminating potentially cytotoxic solvents. Despite this, there is a dearth of literature on scaffold formation via melt electrospinning. This is likely due to...
Article
Surfaces that bind heparin are important for biomaterials for blood deheparinization. In our recent work it was demonstrated that a polypeptide composed of L-lysine and L-leucine (pKL), after immobilization onto tetra(ethylene glycol) terminated self-assembled monolayers (EG4-SAMs), can bind heparin from blood plasma in a selective, concentration-d...
Article
Full-text available
The importance of biomechanics in glucose sensor function has been largely overlooked. This article is the first part of a two-part review in which we look beyond commonly recognized chemical biocompatibility to explore the biomechanics of the sensor-tissue interface as an important aspect of continuous glucose sensor biocompatibility. Part I provi...
Article
Full-text available
This article is the second part of a two-part review in which we explore the biomechanics of the sensor-tissue interface as an important aspect of continuous glucose sensor biocompatibility. Part I, featured in this issue of Journal of Diabetes Science and Technology, describes a theoretical framework of how biomechanical factors such as motion and...
Article
Full-text available
To develop a simple, novel polymeric drug-delivery device for prevention of postoperative bacterial infection after cataract surgery in the developing world. A poly(2-hydroxyethyl-methacrylate) (pHEMA) hydrogel was developed to achieve sustained release characteristics of antibiotics. The in vitro antibiotic release kinetics and efficacy of antibio...
Article
In 2009, the National Academy for Engineering issued the Grand Challenges for Engineering in the 21st Century comprised of 14 technical challenges that must be addressed to build a healthy, profitable, sustainable, and secure global community (http://www.engineeringchallenges.org). Although crucial, none of the NEA Grand Challenges adequately addre...
Article
A set of methods that can be used to create surfaces to accurately control biological reactions is described. These include strategies for inhibiting non-specific reactions, making highly organized surfaces, spatially arraying recognition moieties and characterizing complex surfaces.
Article
Angular-resolved ESCA was used to study single cadmium arachidate monolayers transferred to Si (100) wafers by the Langmuir-Blodgett technique. We find the monolayers to be of high integrity with respect to those defects which enhance the escape probability of substrate photoelectrons through the overlayer. The inelastic mean-free pathlengths of Si...
Article
Nonspecific protein adsorption, particularly fibrinogen (Fg), is thought to be an initiating step in the foreign body response (FBR) to biomaterials by promoting phagocyte attachment. In previous studies, we therefore prepared radiofrequency glow discharge (ethylene oxide)-like tetraglyme (CH(3)O(CH(2)CH(2)O)(4)CH(3)) coatings adsorbing <10 ng/cm(2...
Article
The effect of biomaterial topography on healing in vivo and monocyte/macrophage stimulation in vitro was assessed. A series of expanded polytetrafluoroethylene (ePTFE) materials were characterized by increasing average intranodal distance of 1.2 μm (1.2-ePTFE), 3.0 μm (3.0-ePTFE), and 4.4 μm (4.4-ePTFE), but presented consistent surface chemistry w...
Article
Full-text available
Extracellular matrix (ECM)-based scaffold materials have been used successfully in both preclinical and clinical tissue engineering and regenerative medicine approaches to tissue reconstruction. Results of numerous studies have shown that ECM scaffolds are capable of supporting the growth and differentiation of multiple cell types in vitro and of a...
Article
Decellularization of tissues and organs is a successful platform technology for creating scaffolding materials for tissue engineering and regenerative medicine. It has been suggested that the success of these materials upon implantation is due to the molecular signals provided by the remaining scaffold extracellular matrix (ECM) components presente...
Article
We have developed a thermoresponsive poly(N-isopropyl acrylamide)-based scaffold with degradability and controlled porosity. Biodegradable poly(N-isopropyl acrylamide) hydrogels were synthesized by photocopolymerization of N-isopropylacrylamide with 2-methylene-1,3-dioxepane and polycaprolactone dimethacrylate. The hydrogels' phase transition tempe...
Article
Cell-seeded synthetic polymer scaffolds constitute an emerging technology for urethroplastic applications. The study goal was to identify urethral proteins appropriate for cell attachment and optimize their adsorption onto two types of scaffolds: porous poly(ester urethane) with a poly(caprolactone) soft segment (PEU-PCL) and poly-(96% L/4% D)-lact...
Article
Percutaneous medical devices remain susceptible to infection and failure. We hypothesize that healing of the skin into the percutaneous device will provide a seal, preventing bacterial attachment, biofilm formation, and subsequent device failure. Porous poly(2-hydroxyethyl methacrylate) [poly(HEMA)] with sphere-templated pores (40 microm) and inter...
Article
Full-text available
We demonstrate here a cardiac tissue-engineering strategy addressing multicellular organization, integration into host myocardium, and directional cues to reconstruct the functional architecture of heart muscle. Microtemplating is used to shape poly(2-hydroxyethyl methacrylate-co-methacrylic acid) hydrogel into a tissue-engineering scaffold with ar...
Chapter
Hydrogels are widely used in medicine and offer advantages in many implant situations. However, the body responds to them as with any other material — by walling them off in a foreign body capsule. We show here that by making hydrogels with uniform, interconnected spherical pores of about 35 microns, the healing reaction can be shifted to one of va...
Article
Full-text available
Protein micropatterns have applications in fundamental life sciences and clinical medicine. In this work, we present a new technique to create 2-D protein micropatterns by local activation of a thin film of thermoresponsive plasma-deposited poly(N-isopropylacrylamide) (ppNIPAM) using a computer-controlled infrared laser beam. While the whole substr...
Article
Multifunctional superparamagnetic nanoparticles have been developed for a wide range of applications in nanomedicine, such as serving as tumor-targeted drug carriers and molecular imaging agents. To function in vivo, the development of these novel materials must overcome several challenging requirements including biocompatibility, stability in phys...
Article
Plasma-polymerized tetraglyme films (PP4G) have been modified by exposure to ultraviolet (UV) light from a frequency-doubled argon ion laser (244 nm) and characterized using X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). XPS data indicated that the ether component of the C 1s spectrum declined after UV exposure, while com...
Article
Cellular cardiomyoplasty to replace non-functional tissue following cardiac infarction appears clinically viable. Current strategies utilizing direct injection of cell suspensions are limited by low cell retention, poor cell localization, and high cell death. Synthetic biomaterials developed to enhance cell delivery can lead to problems with immune...
Article
Extracellular matrix (ECM) scaffolds prepared from different tissue sources or using different methods have been demonstrated to have distinctive effects upon cell adhesion patterns and the ability to support and maintain differentiated phenotypes. It is unknown whether the molecular composition or the ultrastructure of the ECM plays a greater role...
Article
Human embryonic stem cells (hESCs) offer a sustainable source of endothelial cells for therapeutic vascularization and tissue engineering, but current techniques for generating these cells remain inefficient. We endeavored to induce and isolate functional endothelial cells from differentiating hESCs. To enhance endothelial cell differentiation abov...
Article
Zwitterionic hydrogels, including poly(sulfobetaine methacrylate) (polySBMA) and poly(carboxybetaine methacrylate) (polyCBMA), and co-polymeric hydrogels of CBMA and 2-hydroxyethyl methacrylate (HEMA) (poly(CBMA-co-HEMA)) were prepared. Their in vitro and in vivo properties were evaluated and compared with those of polyHEMA hydrogels. Bovine aortic...
Article
We aimed to evaluate a new technique using a thermosensitive glue coating for impression cytology of the ocular surface. We prepared plasma polymerized N-isopropyl acrylamide (pNIPAM)-coated parylene C (poly(monochloro-p-xylylene)) films to obtain cytological samples from the conjunctival surface. We compared this new technique with the conventiona...
Article
This work intended to create a nanostructured biomaterial that would bind albumin in a selective and reversible way in order to inhibit the adsorption of other blood proteins and therefore minimize activation of coagulation. Different levels of C18 ligand have been immobilized on poly(2-hydroxyethyl methacrylate) (pHEMA). We hypothesize that sample...
Article
Intraocular lens implantation after opacified natural lens removal is the primary treatment for cataracts in developed countries. Cataract surgery is generally considered safe, but entails significant risks in countries where sophisticated sterile operating theaters are not widely available. Post-operative infection (endophthalmitis) is a potential...
Article
Sum-frequency generation (SFG) vibrational spectroscopy is used to study the surface and the underlying substrate of both homogeneous and mixed self-assembled monolayers (SAMs) of 11-mercaptoundecyl-1-sulphobetainethiol (HS(CH(2))(11)N(+)(CH(3))(2)(CH(2))(3)SO(3)(-)) and 1-mercapto-11-undecyl tetra(ethylene glycol) (HS(CH(2))(11)O(CH(2)CH(2)O)(4)OH...
Article
Electrospun scaffolds have been increasingly used in tissue engineering applications due to their size-scale similarities with native extracellular matrices. Their inherent fibrous features may be important in promoting cell attachment and proliferation on the scaffolds. In this study, we explore the technique of fabricating electrospun fibers with...
Article
Full-text available
In this article, the authors describe new approaches to synthesize and pattern surfaces with poly[oligo(ethylene glycol) methyl methacrylate] (POEGMA) polymer brushes synthesized by surface-initiated atom transfer radical polymerization. These patterned coatings confer "nonfouling" properties protein and cell resistance-to the surface in a biologic...
Article
This study focuses on the selective binding of albumin to a nanostructured surfaces to inhibit other blood proteins from adsorbing thereby reducing platelet adhesion and activation. Tetra (ethylene-glycol)-terminated self-assembled monolayers (EG4 SAMs) with different percentages of C18 ligands on the surface were characterized by contact angle mea...