Nicholas A. Peppas

Bio: Nicholas A. Peppas is an academic researcher from University of Texas at Austin. The author has contributed to research in topics: Self-healing hydrogels & Drug delivery. The author has an hindex of 141, co-authored 825 publications receiving 90533 citations. Previous affiliations of Nicholas A. Peppas include National Technical University & University of Texas System.

Method and process for the production of multi-coated recognitive and releasing systems

Abstract: The present invention includes compositions, methods, systems for the controlled delivery of an active agent within a polymeric network upon the binding of a molecule that decreases the structural integrity of the polymeric network at one or more micro- or nanovacuoles.

Reaction engineering aspects of suspension polymerization

Abstract: Suspension polymerization is used for the production of polymer particles with diameter in the range of 50–750 μm. The particle size distribution of the particles produced in batch-suspension polymerization is calculated using a population balance model. Power laws are derived for the average particle size and the standard deviation of the distribution. It is found that both quantities scale to the stable droplet mass of the initial dispersion of the organic phase into the aqueous one, which is a function of the agitation rate and the surface tension.

Dynamic swelling behavior of interpenetrating polymer networks in response to temperature and pH

Abstract: Temperature responsive hydrogels based on ionic polymers exhibit swelling transitions in aqueous solutions as a function of shifting pH and ionic strength, in addition to temperature. Applying these hydrogels to useful applications, particularly for biomedical purposes such as drug delivery and regenerative medicine, is critically dependent on understanding the hydrogel solution responses as a function of all three parameters together. In this work, interpenetrating polymer network (IPN) hydrogels of polyacrylamide and poly(acrylic acid) were formulated over a broad range of synthesis variables using a fractional factorial design, and were examined for equilibrium temperature responsive swelling in a variety of solution conditions. Due to the acidic nature of these IPN hydrogels, usable upper critical solution temperature (UCST) responses for this system occur in mildly acidic environments. Responses were characterized in terms of maximum equilibrium swelling and temperature-triggered swelling using turbidity and gravimetric measurements. Additionally, synthesis parameters critical to achieving optimal overall swelling, temperature-triggered swelling, and sigmoidal temperature transitions for this IPN system were analyzed based on the fractional factorial design used to formulate these hydrogels.

Intelligent Biomaterials as Pharmaceutical Carriers in Microfabricated and Nanoscale Devices

Abstract: The emergence of micro- and nanoscale science and engineering has provided new avenuas for engineering materials with macromolecular and even molecular-scale precision, leading to diagnostic and therapeutic technologies that will revolutionize the way healthcare is administered Biomaterials have evolved from off-the-shelf products to materials designed with molecular precision to exhibit the desired properties for a specific application, often mimicking biological systems Controlling interactions at the level of natural building blocks, from proteins to cells, facilitates the novel exploration, manipulation, and application of living systems and biological phenomena In addition, polymer networks with precisely engineered binding sites have been created via molecular imprinting, where functional monomers are preassembled with a target molecule and then the structure is locked with network formation Nanoscale science and engineering have accelerated the development of novel drug delivery systems and led to enhanced control over how a given pharmaceutical is administered, helping biological potential to be transformed into medical reality Micro- and nanoscale devices have been fabricated using integrated-circuit processing techniques, enabling strict temporal control over drug release The advantages of these microdevices include simple release mechanisms, very accurate dosing, the capability of complex release patterns, the potential for local delivery, and possible biological drug stability enhancement by means of storage in a microvolume that can be precisely controlled In particular, the development of polymer systems that are able to interact with their environment in a thermodynamically responsive manner has led to novel intelligent biomaterials and applications Intelligent biomedical materials can be used for the delivery of drugs, peptides, and proteins; as targeting agents for site-specific delivery; or as components for the preparation of protein or drug conjugates These intelligent materials are attractive options as functional components in micro- and nanodevices because of the ease with which recognition and actuation properties can be precisely tailored Recent developments in intelligent materials and nano- or microdevices for drug delivery systems are the emphasis of this review, which addresses the use of intelligent biomedical materials as carriers for the development of novel pharmaceutical formulations

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

The Design and Analysis of Experiments

Abstract: THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

Harrison's Principles of Internal Medicine

Abstract: The 11th edition of Harrison's Principles of Internal Medicine welcomes Anthony Fauci to its editorial staff, in addition to more than 85 new contributors. While the organization of the book is similar to previous editions, major emphasis has been placed on disorders that affect multiple organ systems. Important advances in genetics, immunology, and oncology are emphasized. Many chapters of the book have been rewritten and describe major advances in internal medicine. Subjects that received only a paragraph or two of attention in previous editions are now covered in entire chapters. Among the chapters that have been extensively revised are the chapters on infections in the compromised host, on skin rashes in infections, on many of the viral infections, including cytomegalovirus and Epstein-Barr virus, on sexually transmitted diseases, on diabetes mellitus, on disorders of bone and mineral metabolism, and on lymphadenopathy and splenomegaly. The major revisions in these chapters and many

Understanding biophysicochemical interactions at the nano–bio interface

Abstract: Rapid growth in nanotechnology is increasing the likelihood of engineered nanomaterials coming into contact with humans and the environment. Nanoparticles interacting with proteins, membranes, cells, DNA and organelles establish a series of nanoparticle/biological interfaces that depend on colloidal forces as well as dynamic biophysicochemical interactions. These interactions lead to the formation of protein coronas, particle wrapping, intracellular uptake and biocatalytic processes that could have biocompatible or bioadverse outcomes. For their part, the biomolecules may induce phase transformations, free energy releases, restructuring and dissolution at the nanomaterial surface. Probing these various interfaces allows the development of predictive relationships between structure and activity that are determined by nanomaterial properties such as size, shape, surface chemistry, roughness and surface coatings. This knowledge is important from the perspective of safe use of nanomaterials.