U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications by: Dean C Ripple (Fed)

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 1 - 25 of 80

Humanized Monoclonal Antibody IgG1k, NISTmAb RM 8671 Summary of 5 Year Stability Verification (5YSV)

March 31, 2023
Author(s)
Katharina Yandrofski, John E. Schiel, Trina Mouchahoir, Srivalli Telikepalli, N. Alan Heckert, Dean C. Ripple, Paul C. DeRose, Karen W. Phinney, John Marino
NISTmAb RM 8671 is an IgG1κ monoclonal antibody that has been extensively characterized and released as the first of its kind biopharmaceutical reference material in 2016. This material was intended primarily for use in evaluating the performance of

An Interlaboratory Study of Potential Visible Protein-Like Particle Standards

November 1, 2022
Author(s)
Srivalli Telikepalli, Michael J. Carrier, Dean C. Ripple
Visible protein-like particle standards can improve visual inspection and/or appearance testing practices used in the biotechnology industry. It will improve assay performance resulting in better alignment and more standardized training among different

Size and Number Concentration Measurements of Polystyrene Nanoparticle Suspensions using Several Different Techniques

September 8, 2022
Author(s)
Paul C. DeRose, Kurt D. Benkstein, Elzafir B. Elsheikh, Adolfas K. Gaigalas, Sean Lehman, Dean C. Ripple, Linhua Tian, Wyatt N. Vreeland, Adam York, Yu-Zhong Zhang, Lili Wang
The number concentrations of nominal 100 nm, 200 nm and 500 nm diameter, fluorescently-labeled polystyrene nanosphere suspensions were measured using seven different techniques. Diameter values were also measured where possible. The diameter values were

Testing Precision Limits of Neural Network-Based Quality Control Metrics in High-Throughput Digital Microscopy

January 26, 2022
Author(s)
Chris Calderon, Dean C. Ripple, Charudharshini Srinivasan, Youlong Ma, Michael J. Carrier, Theodore Randolph, Thomas O'Connor
Digital microscopy is used to monitor particulates such as protein aggregates within biologic pharmaceutical products. The digital images that result encode a wealth of information, but much of this image data is underutilized in pharmaceutical process

Establishing Standards and Methods for Qualification and Validation of New Particle Measurement Technologies

November 12, 2019
Author(s)
Srivalli Telikepalli, Dean C. Ripple, Kurt D. Benkstein, Kristen L. Steffens, Michael J. Carrier, Christopher B. Montgomery
Numerous particle sizing and counting methods exist for measuring particles in the submicrometer, subvisible, and visible size range. This article will briefly describe some key aspects that need to be considered for the most commonly used methods in order

Phase-Appropriate Application of Analytical Methods to Monitor Subvisible Particles Across the Biotherapeutic Drug Product Life Cycle

October 30, 2019
Author(s)
Roman Mathaes, Linda Narhi, Andrea Hawe, Anja Matter, Karoline Bechtold-Peters, Sophia Kenrick, Sambit Kar, Olga Laskina, John Carpenter, Richard E. Cavicchi, Ellen Koepf, Neil Lewis, Rukman De Sliva, Dean C. Ripple
The phase-appropriate application of analytical methods to characterize, monitor, and control particles is an important aspect of the development of safe and efficacious biotherapeutics. The AAPS Product Attribute and Biological Consequences (PABC) focus

Development of Protein-Like Reference Material for Semi-Quantitatively Monitoring Visible Proteinaceous Particles in Biotherapeutics

June 17, 2019
Author(s)
Srivalli Telikepalli, Kristen Gonzalez, Sonia Dragulin-Otto, Dean C. Ripple, Michael J. Carrier, M Khan
Visual inspection of biotherapeutics is required at various stages of drug production and manufacturing to ensure quality and consistency of drug products. Inherent particles, composed of aggregated protein from the drug-product, may potentially pose

Reference Material 8634: Ethylene Tetrafluoroethylene for Particle Size Distribution and Morphology

May 1, 2019
Author(s)
Dean C. Ripple, Srivalli Telikepalli, Kristen L. Steffens, Michael J. Carrier, Christopher B. Montgomery, Nicholas W. Ritchie, John Lu
Reference Material (RM) 8634 is a NIST particle standard produced from abraded ethylene tetrafluoroethylene (ETFE), a chemically inert polymer, that will help standardize and allow more accurate monitoring of subvisible proteinaceous particles in

The NISTmAb Reference Material 8671 Value Assignment, Homogeneity, and Stability

March 1, 2018
Author(s)
John E. Schiel, Abigail Turner, Catherine A. Mouchahoir, Katharina S. Yandrofski, Srivalli Telikepalli, Jason King, Paul C. DeRose, Dean C. Ripple, Karen W. Phinney
The NISTmAb Reference Material (RM) 8671 is intended to be the common industry standard monoclonal antibody for pre-competitive research in harmonizing current state-of-the-art technology and designing next generation characterization technologies for

Development of Orthogonal NISTmAb Size Heterogeneity Control Methods

February 10, 2018
Author(s)
Abigail Turner, Katharina S. Yandrofski, Srivalli Telikepalli, N. Alan Heckert, James J. Filliben, Dean C. Ripple, John E. Schiel
The NISTmAb is an innovative monoclonal antibody reference material from the National Institute of Standards and Technology; it is a class-representative IgG1κ intended to serve as a pre-competitive platform for harmonization and technology development in

Variable Threshold Method for Determining the Boundaries of Imaged Subvisible Particles

February 15, 2017
Author(s)
Richard E. Cavicchi, Cayla Collett, Srivalli Telikepalli, Zhishang Hu, Michael J. Carrier, Dean C. Ripple
An accurate assessment of particle characteristics and concentrations in pharmaceutical products by flow imaging requires accurate particle sizing and morphological analysis. Analysis of images begins with the definition of particle boundaries from the

Analytical Gaps and Challenges for Particles in the Submicrometer Size Domain

November 30, 2016
Author(s)
Scott Aldrich, Shawn Cao, Andrea Hawe, Desmond Hunt, Linda Narhi, Dean C. Ripple, Satish Singh
This Stimuli article provides a technical discussion of the available technologies for submicrometer particle analysis, including consideration of the advantages, disadvantages, and technical gaps for each application. These methods can be used in the

SRM 1967a: High-Purity Platinum Thermoelement

March 9, 2016
Author(s)
Karen M. Garrity, Weston L. Tew, Dean C. Ripple
Consisting of a 1 m long piece of 0.5 mm diameter platinum wire, SRM 1967a meets the requirements for a thermoelectric reference material for temperatures from 196 °C up to approximately 1700 °C. We have tested the thermoelectric emf of four SRM 1967a

Protein Particles (0.1 ym to 100 ym)

October 15, 2015
Author(s)
Dean C. Ripple, Linda Narhi
Protein molecules in solution can form proteinaceous particles by a variety of aggregation processes. The size and concentration of these particles is an important quality attribute for therapeutic MAb solutions. In this chapter, we describe the techniques

Sub-visible (2 mm to 100 mm) particle analysis during biotherapeutic drug product development: Part 1, considerations and strategy

April 1, 2015
Author(s)
Dean C. Ripple, Linda Narhi, Natliya Afonina, Satish Singh, Andrea Herre, Patrick Garidel, Atanas Koulov, Vincent Corvari, Thomas Spitznagel, Paolo Mangiagalli, Irene Cecchini, Klaus Wuchner, Tony Lubiniecki, Hanns-Christian Mahler, Roland Schmidt, Alla Polozova, Patricia Cash, Andrew Weiskopf, Douglas Nesta, Mara Rossi, Robert Simler
Measurement and characterization of particles in the 1 µm to 100 µm range (sub-visible particles), including protein aggregates, is an important part of every stage of protein therapeutic development. The tools used and the ways in which the information

The Use of Index-Matched Beads in Optical Particle Counters

January 8, 2015
Author(s)
Dean C. Ripple
Although multiple methods are available for counting and sizing of protein particles over a broad range of sizes, differences in physical properties between common polystyrene-bead reference materials and the actual protein particles of interest result in