{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,13]],"date-time":"2026-09-13T18:18:52Z","timestamp":1789323532334,"version":"build-2803163510"},"reference-count":50,"publisher":"Oxford University Press (OUP)","issue":"3","license":[{"start":{"date-parts":[[2022,5,16]],"date-time":"2022-05-16T00:00:00Z","timestamp":1652659200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["1827717"],"award-info":[{"award-number":["1827717"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2022,7,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Lyophilization is a common unit operation in pharmaceutical manufacturing but is a prolonged vacuum drying process with poor energy utilization. Microwave-assisted vacuum drying has been investigated to accelerate the lyophilization process. However, the literature lacks methodical approaches that consider the lyophilizer, the lyophilizate, the microwave power uniformity, the resulting heat uniformity, and the scalability. We present a microwave\u2013vacuum drying method based on the statistical electromagnetics theory. The method offers an optimum frequency selection procedure that accounts for the lyophilizer and the lyophilizate. The 2.45\u00a0GHz frequency conventionally utilized is proven to be far from optimum. The method is applied in a microwave-assisted heating configuration to pharmaceutical excipients (sucrose and mannitol) and different myoglobin formulations in a lab-scale lyophilizer. At 18\u00a0GHz frequency and 60\u00a0W microwave power, the method shows nearly three times speed-up in the primary drying stage of sucrose relative to the conventional lyophilization cycle for typical laboratory batches. The uniformity of the microwave power inside the chamber is controlled within \u00b1 1 dB. The resulting heating uniformity measured through residual moisture analysis shows 12.7% of normalized SD of moisture level across the batch in a microwave-assisted cycle as opposed to 15.3% in the conventional cycle. Conventional and microwave lyophilized formulations are characterized using solid-state hydrogen-deuterium exchange-mass spectrometry (ssHDX-MS), solid-state Fourier transform infrared spectroscopy (ssFTIR), circular dichroism (CD), and accelerated stability testing (AST). Characterization shows comparable protein structure and stability. Heat and mass transfer simulations quantify further effects of optimal volumetric heating via the high-frequency statistical microwave heating.<\/jats:p>","DOI":"10.1093\/pnasnexus\/pgac052","type":"journal-article","created":{"date-parts":[[2022,5,16]],"date-time":"2022-05-16T09:30:21Z","timestamp":1652693421000},"source":"Crossref","is-referenced-by-count":18,"title":["Statistical electromagnetics for industrial pharmaceutical lyophilization"],"prefix":"10.1093","volume":"1","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4287-5422","authenticated-orcid":false,"given":"Ahmed","family":"Abdelraheem","sequence":"first","affiliation":[{"name":"Birck Nanotechnology Center, Purdue University , 1205\u00a0W State St, West Lafayette, 47907 IN, USA"},{"name":"School of Electrical and Computer Engineering, Purdue University , Electrical Engineering Building, 465, Northwestern Ave, West Lafayette, 47907 IN, USA"},{"name":"Electronic Engineering Department, Military Technical College, Al-Khalifa Al-Mamoon Street Kobry Elkobbah , Cairo, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rishabh","family":"Tukra","sequence":"additional","affiliation":[{"name":"Birck Nanotechnology Center, Purdue University , 1205\u00a0W State St, West Lafayette, 47907 IN, USA"},{"name":"Department of Industrial and Physical Pharmac, College of Pharmacy, Purdue University , Heine (Robert E.) Pharmacy Bldg, 575\u00a0W Stadium Ave, West Lafayette, 47907 IN, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Petr","family":"Kazarin","sequence":"additional","affiliation":[{"name":"Birck Nanotechnology Center, Purdue University , 1205\u00a0W State St, West Lafayette, 47907 IN, USA"},{"name":"School of Aeronautics and Astronautics, Purdue University , 701\u00a0W Stadium Ave, West Lafayette, 47907 IN, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4477-5778","authenticated-orcid":false,"given":"Michael D","family":"Sinanis","sequence":"additional","affiliation":[{"name":"Birck Nanotechnology Center, Purdue University , 1205\u00a0W State St, West Lafayette, 47907 IN, USA"},{"name":"School of Electrical and Computer Engineering, Purdue University , Electrical Engineering Building, 465, Northwestern Ave, West Lafayette, 47907 IN, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elizabeth M","family":"Topp","sequence":"additional","affiliation":[{"name":"Birck Nanotechnology Center, Purdue University , 1205\u00a0W State St, West Lafayette, 47907 IN, USA"},{"name":"Department of Industrial and Physical Pharmac, College of Pharmacy, Purdue University , Heine (Robert E.) Pharmacy Bldg, 575\u00a0W Stadium Ave, West Lafayette, 47907 IN, USA"},{"name":"National Institute for Bioprocessing Research and Training , Blackrock, Co. Dublin A94 X099, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2123-9064","authenticated-orcid":false,"given":"Alina","family":"Alexeenko","sequence":"additional","affiliation":[{"name":"Birck Nanotechnology Center, Purdue University , 1205\u00a0W State St, West Lafayette, 47907 IN, USA"},{"name":"School of Aeronautics and Astronautics, Purdue University , 701\u00a0W Stadium Ave, West Lafayette, 47907 IN, USA"},{"name":"Davidson School of Chemical Engineering, Purdue University , 480 Stadium Mall Drive, West Lafayette, 47907 IN, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4993-1653","authenticated-orcid":false,"given":"Dimitrios","family":"Peroulis","sequence":"additional","affiliation":[{"name":"Birck Nanotechnology Center, Purdue University , 1205\u00a0W State St, West Lafayette, 47907 IN, USA"},{"name":"School of Electrical and Computer Engineering, Purdue University , 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