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Company History

Heartland Assays began as a joint venture between Dr. Ronald Horst and Dr. Bruce Hollis. Dr. Horst and Dr. Hollis have a combined experience of over 75 years of analytical instrument and method development, and application of these methodologies to assess Vitamin D status in humans and animals as well as Vitamin D analysis of supplements, food, and feed.

Dr. Horst received his B.S. from West Virginia University and his Ph.D. from the University of Wisconsin. Dr. Horst has significant contributions in the fields of nutrition, endocrinology, and physiology and has over 43 years of research experience with more than six hundred research papers, reviews, chapters and abstracts.

Dr. Hollis received his M.S. from the Ohio State University and his Ph.D. in Experimental Nutrition from the University of Guelph. Currently, Dr. Hollis is a Professor of Pediatrics at The Medical University of South Carolina, and he has also been contributing to Vitamin D research for over 35 years with over 200 peer-reviewed articles.

Dr. Horst and Dr. Hollis together founded Heartland Assays, LLC, where they have provided analytical services for many large-scale projects including the USDA National Food and Nutrient Analysis Program (NFNAP) and the Cohort Consortium Vitamin D Pooling Project of Rarer Cancers (VDPP).

In 2010, Metabolic Technologies, Inc. and Heartland Assays, LLC formed a strategic partnership to better serve our clientele.  Heartland Assays and the analytical services division of Metabolic Technologies, Inc. merged under one name – Heartland Assays, which was made effective on January 1, 2015. 

Former laboratory supervisor at Metabolic Technologies, Inc. and now current laboratory supervisor at Heartland Assays, Dr. John A. Rathmacher, received his B.S. and M.S. at Purdue University and went on to receive his Ph.D. from Iowa State University. Dr. Rathmacher not only has conducted extensive research on 3-Methylhistidine (3MH) analysis and modeling protein turnover, but has over 10 referred publications as well as 20 abstracts on the metabolic modeling and analytical methodologies. Dr. Rathmacher has been with Metabolic Technologies, Inc. for about 19 years and has conducted research on ß-hydroxy-ß-methylbutyrate (HMB) for nearly 25 years with 39 peer-reviewed articles.

With the leadership and expertise of Dr. Rathmacher and his analytical group, combined with the skilled Heartland Assays’ team, we believe we’ve created a best-of-class analytical lab to better serve our customers and their expanding needs.

Mission Statement

Heartland Assays' mission is to provide cutting-edge analytics, robust methodologies, and precise, accurate results for their clientele. Heartland Assays can help you with the assessment and evaluation of Vitamin D (including metabolites and binding proteins), physiological amino acids, β-hydroxy-β-methylbutyrate (HMB), hormones (by ELISA), and protein analysis. These analyses can be performed with all types of sample matrices including biological tissues and fluids from cell cultures, animals, and humans, and all types of foods, feeds, concentrates, and supplements. With cutting-edge technology and over 95 years of combined experience, Heartland Assays has the knowledge, skills, and expertise to support all of your analytical needs.

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