{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,6]],"date-time":"2025-10-06T16:40:10Z","timestamp":1759768810417,"version":"build-2065373602"},"reference-count":5,"publisher":"S. Karger AG","issue":"4","license":[{"start":{"date-parts":[[2025,7,2]],"date-time":"2025-07-02T00:00:00Z","timestamp":1751414400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"},{"start":{"date-parts":[[2025,7,2]],"date-time":"2025-07-02T00:00:00Z","timestamp":1751414400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Skin Pharmacol Physiol"],"abstract":"<jats:p>Introduction: A new method for conducting in vitro release testing (IVRT) was developed by adapting Higuchi\u2019s square root approximation for use with UV-Vis spectrophotometry, and over the counter hydrocortisone formulations at 0.5% and 1.0% concentrations. This IVRT method was investigated for the required validation elements as specified by abbreviated new drug applications (ANDAs) and USP General Chapter &lt;1724&gt; for linearity and range, precision and reproducibility, and discrimination sensitivity, specificity, and selectivity. Methods: IVRT kinetic experiments were conducted using UV-Vis spectrophotometer, a quartz cuvette, with measurements collected every 15 s for 5 min, and methanol as the receptor solution. Six measurements of the 1% hydrocortisone formulation were conducted over 3 different days, for a total of 18 measurements. The 0.5% formulation was measured 6 times over 1 day. Release rates were obtained by plotting the slope of Abs&lt;sub&gt;242&lt;\/sub&gt; vs. \u221at. HPLC was used to demonstrate specificity via an alternate analytical technique and to show membrane inertness. Results: The hydrocortisone cream formulations demonstrated specificity via HPLC compared to a USP traceable hydrocortisone reference standard. IVRT sensitivity and selectivity were demonstrated by the statistically different release rates (slopes) of the 0.5% vs. the 1% hydrocortisone formulations at 90% confidence interval (75\u2013133.33%). Linearity throughout the duration of the assay was demonstrated through a r2 value of \u22650.97 for each experiment and for each formulation. All intra-run and inter-run precision calculations relating to the IVRT experiments had %CV values of \u226415%. Conclusion: IVRT experiments were conducted using UV-Vis spectrophotometry kinetic monitoring of 0.5% and 1% hydrocortisone formulations. This IVRT method was validated for specificity, selectivity, sensitivity, linearity and range, precision and reproducibility following the guidance for ANDAs and USP General Chapter &lt;1724&gt;, thus demonstrating the capability of UV-Vis spectrophotometry as a reliable way of discerning release rates of semisolid formulations. This novel approach can be conducted in a matter of minutes as opposed to hours, a vast improvement over conventional IVRT studies. <\/jats:p>","DOI":"10.1159\/000546534","type":"journal-article","created":{"date-parts":[[2025,7,2]],"date-time":"2025-07-02T12:02:38Z","timestamp":1751457758000},"page":"165-171","source":"Crossref","is-referenced-by-count":0,"title":["Kinetic Monitoring of in vitro Release Testing Using UV-Vis Spectrophotometry with Hydrocortisone Creams"],"prefix":"10.1159","volume":"38","author":[{"given":"Kelsey","family":"Leach","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-6594-8566","authenticated-orcid":false,"given":"Lola","family":"Sibaud","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bradley","family":"Towey","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"127","published-online":{"date-parts":[[2025,7,2]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","DOI":"10.1002\/wics.1310"},{"key":"ref2","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijpharm.2017.09.049"},{"key":"ref3","doi-asserted-by":"publisher","DOI":"10.14227\/dt200213p15"},{"key":"ref4","doi-asserted-by":"publisher","DOI":"10.1002\/jps.2600501018"},{"key":"ref5","doi-asserted-by":"publisher","DOI":"10.3390\/pharmaceutics12020119"}],"container-title":["Skin Pharmacology and Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/karger.com\/article-pdf\/doi\/10.1159\/000546534","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,6]],"date-time":"2025-10-06T16:07:10Z","timestamp":1759766830000},"score":1,"resource":{"primary":{"URL":"https:\/\/karger.com\/article\/doi\/10.1159\/000546534"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,7,2]]},"references-count":5,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2025,10,6]]},"published-print":{"date-parts":[[2025,10,8]]}},"URL":"https:\/\/doi.org\/10.1159\/000546534","archive":["Portico"],"relation":{"is-supplemented-by":[{"id-type":"doi","id":"10.6084\/m9.figshare.29148410","asserted-by":"subject"}]},"ISSN":["1660-5527","1660-5535"],"issn-type":[{"type":"print","value":"1660-5527"},{"type":"electronic","value":"1660-5535"}],"subject":[],"published":{"date-parts":[[2025,7,2]]}}}