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Sandra M Da Silva (Fed)

Research Chemist

Sandra works as a Research Chemist in the Biomaterials Group. Her work is focused on developing methods and reference materials for microbial characterization to support stakeholders from different fields where microbes play a role, such as live biotherapeutics and human health (e.g., gut microbiome). Current research interests can be observed in the following projects:

  • Microbial metabolomics 
    • Whole Human Stool reference material (RM 8048)
  • Microbial Quantification and Viability
    • Escherichia coli reference material
    • Saccharomyces cerevisiae reference material (RM8230)
  • Rapid Microbial Testing Methods (RMTM)


  • Crivat, G.; Da Silva, S. M.; Quach, A. D.; Kethineedi, V.R.; Rosenzweig, Z., 2014. “Luminescent Nanoparticle-Based Probes for Bioassays” Biomedical Photonics Handbook, Second Edition, Taylor & Francis Group; (ISBN: 978-1-4200-8516-7)


  1. Da Silva SM, Lang, AP, Dos Santos, APF, Cabelo, MC, Ciscato, LFML, Bartoloni, FH, Bastos, EL and Baader, WJ, “Cyclic Peroxidic Carbon Dioxide Dimer Fuels Peroxyoxalate Chemiluminescence”. J. Org. Chem., 86(17), 11434-41, 2021.
  2. Da Silva SM, Piotrowski PK, Jones CM, Servetas SL, Lin NJ, Lippa KA and Jackson SA. “A NIST-hosted Virtual Workshop on Measuring SARS-COV-2 in wastewater and Fecal Material: A Call for Standards. NIST Special Publication (NIST SP1256), 2020.
  3. Mandal R, Cano R, Davis CD, Hayashi D, Jackson SA, Jones CM, Lampe JW, Latullippe ME, Lin NJ, Lippa KA, Piotrowski P, Da Silva SM, Swanson KS and Wishart DS. “Workshop report: Toward the Development of a human whole stool reference material for metabolomic and metagenomic gut microbiome measurements. Metabolomics, 2-16:119, 2020.
  4. Berkstein KD, Da Silva SM, Lin NJ and Ripple DC. “Evaluating changes to Ralstonia pickettii in high-purity water to guide selection of potential calibration materials for online water bioburden analyzers”. J. Ind. Microbiol. Biotech., 46pages1469-78. 2019.
  5. Da Silva SM, Vang LK, Olson ND, Downey AS, Kelman Z, Salit ML, Lin NJ and Morrow JB, Evaluation of microbial qPCR workflows using engineered Saccharomyces cerevisiae, Biomolecular Detection and Quantification, 27-33(7), 2016.
  6. Haghpanah J, Tu R, Da Silva S, Yang D, Mueller S, Weder C, Foster JE, Sacui I, Gilman J, Montclare J, 2013, "Bionanocomposites: Differential Effects of Cellulose Nanocrystals on Protein Diblock Copolymers", Biomacromolecules, 14(12), 4360-7.
  7. Goncalves LCP, Da Silva SM, DeRose PC, Ando RA and Bastos EL, 2013 “Beetroot-Pigment-Derived Colorimetric Sensor for Detection of Calcium Dipicolinate in Bacterial Spores”, PLOS One, 8(9), e73701
  8. Da Silva SM, Urbas AA, Filliben JJ and Morrow JB; 2013 “Recovery balance: a method for estimating losses in a Bacillus anthracis spore sampling protocol”, J. Applied Microbiology, 114(3), 807-18.
  9. Bastos EL, Da Silva SM, Baader WJ; 2013 “Solvent Cage Effects: Basis of a General Mechanism for Efficient Chemiluminescence”, Journal of Organic Chemistry, 78, 4432-9.
  10. Downey AS, Da Silva S.M, Olson ND, Filliben JJ and Morrow JB., “Impact of processing method on recovery of bacteria from wipes used in biological surface sampling” Applied and Environmental Microbiology, 2012, 78, 5872-5881.
  11. Belostotsky I, Da Silva SM, Paez MG and Indig GL, “Mitochondrial Targeting for Photochemotherapy. Can Selective Tumor Cell Killing Be Predicted Based on n-octanol/water Distribution Coefficients? Biotechnic. Histochem. 2011, 86(5), 302-314.
  12. Da Silva SM, Filliben JJ and Morrow JB., Parameters Affecting Spore Recovery from Wipes Used in Biological Surface Sampling, Applied and Environmental Microbiology, 2011, 77(7), 2374-2380.
  13. Crivat, G., Da Silva, S.M., Reyes, D. R., Locascio, L. E., Gaitan, M., Rosenzweig, N. and Rosenzweig Z.  “Quantum Dot FRET-Based Probes in Thin Films Grown in Microfluidic Channels, J. Am. Chem. Soc. 2010, 132(5), 1460-1461.


  • 2021 NIST MML Accolade - For the development of a multi-divisional collaboration ("The Poop Team") aimed at the production of a Human Gut Microbiome (a.k.a. human fecal) Reference Material for multi-omic analyses – MML Collaboration and Teamwork category.
  • 2020 NIST Gold Medal Award - Recognized for developing standards to improve the decision-making process and response to biological threat agents by first responders.  The suite of standards includes standard methods for powder collection, operational guidelines for first responders, and the first NIST live cell reference material. The suite of standards has been refined in field and interlaboratory studies with professional rescue personnel. These efforts have strengthened the national biothreat response and increased quality of results used to support high-stakes public safety decision-making.
  • 2018 NIST MML Accolade - For deployment of a quantitative yeast material that enables safe on-site training for first responders to increase confidence in biothreat detection – MML distinguished associated category.
  • 2016 NIST MML Accolade - Accolade For advancing measurement methods and standards to support the emerging field of microbial metrology - MML distinguished associated category.


Multi'omic Characterization of Human Whole Stool RGTMs

Amanda L. Bayless, Sandra M. Da Silva, Clay Davis, Abraham Kuri Cruz, Tracey Schock, Stephanie Servetas, Paulina Piotrowski
The gut microbiome plays a critical role in a vast and disparate set of health and disease states, including cancer and obesity. Human fecal is a complex

Enhancing untargeted metabolomics using metadata-based source annotation

Scott Jackson, Paulina Piotrowski, Nancy Lin, Sandra M. Da Silva, Katrice Lippa, Christina Jones, Stephanie Servetas, Julia Gauglitz, Kiana West, Wout Bittremieux, Candace Williams, Kelly Weldon, Morgan Panitchpakdi, Francesca Ottavio, Christine Aceves, Elizabeth Brown, Nicole Sikora, Alan Jarmusch, Cameron Martino, Pieter Dorrestein, Rob Knight, Rachel Dutton, Austin Swafford, Monica Guma, Norberto Peporine Lopes, Brigid Boland, Michelli Oliveira, Mark Manary, Maria Gloria Dominguez-Bello, Kenneth Wright, Julia Beauchamp-Walters, Kyung Rhee, Jae Kim, Megan Doty, Robert Terkeltaub, David Gonzalez, Curt Wittenberg, Tatyana Kalashnikova, Parambir Dulai, Douglas Galasko, Rima Kaddurah Daouk, Robert Mills, Paulo Louzada-Junior, Rene Donizeti Ribeiro Oliveira, Thaigo Mattar Cunha, Flavio Protaso Veras, Rodrigo Moreira Silva, Juliano Geraldo Amaral, Lucas Maciel Mauriz Marques, Barry Bradford, Lourdes Herrera, Gail Ackermann, Dana Withrow, Daniela Vargas Robles, Kate Sprecher, Clarisse Marotz, Mingxun Wang, Emmanuel Elijah, Dominic Nguyen, Qiyun Zhu, Daniel McDonald, Edgar Diaz, Pedro Belda-Ferre, Katharina Spengler, Abigail Johnson, Gregory Humphrey, MacKenzie Bryant, Tara Schwartz, Lindsay Goldasich, Fernando Vargas, Roxana Coras, Justin Schaffer, Erfan Sayyari, Kathleen Dorrestein, Michael Meehan, Anupriya Tripathi
Human untargeted metabolomics studies annotate only 10% of molecular features. We introduce reference-data-driven analysis to match metabolomics tandem mass

Key Considerations for Microbial Viability Measurements

Joy Dunkers, Sandra M. Da Silva, Stephanie Servetas, James J. Filliben, Guilherme L. Pinheiro, Nancy Lin
Making reliable measurements of antimicrobial killing efficacy requires careful consideration of the sources of biological variability, measurement bias and
Created September 12, 2019, Updated February 9, 2023