Performance of qualitative urinary hCG assays

Significant differences in the sensitivity of eight frequently used qualitative urine human chorionic gonadotropin (hCG) tests in Belgium were observed in this study. Although most manufacturers claimed to detect hCG levels as low as 25 mIU/ml, only two out of six tests for home use and one out of two tests for professional use only, achieved the claimed detection limit. According to a survey, we performed among 20 acute care hospitals, 80% of the surveyed hospitals claimed to use these types of hCG analysis in a diagnostic setting. Unsatisfactory performance of these point-of-care testing (POC) assays for urinary hCG could have major consequences in a hospital setting, exposing the early pregnant woman to harmful diagnostic and therapeutic procedures. Although qualitative urine hCG tests are rapid and convenient, determination of hCG in blood remains the gold standard for the diagnosis of pregnancy.peerreview_statement: The publishing and review policy for this title is described in its Aims & Scope. aims_and_scope_url: http://www.tandfonline.com/action/journalInformation?show=aimsScope&journalCode=yacb20status: publishe

Temperature‐Responsive Photonic Devices Based on Cholesteric Liquid Crystals

Cholesteric liquid crystals (CLCs) are a major class of photonic materials that display selective reflection properties arising from their helical ordering. The temperature response of CLCs, comprising of dynamic reflection color changes upon variation of temperature, can be exploited using material systems consisting of small mesogenic molecules, polymer‐dispersed liquid crystals (PDLCs), polymer‐stabilized liquid crystals (PSLCs), or liquid‐crystalline polymers. Taking advantage of the easy processability and flexibility of the molecular design, these temperature‐responsive CLCs have been fabricated into different forms of photonic devices, including cells, coatings, free‐standing films, and three‐dimensional objects. Temperature‐responsive devices developed from CLCs could be integrated for application in temperature sensors, energy‐saving smart windows, smart labels, actuators, and adding aesthetically pleasing features to common objects. This review summarizes the device capabilities of the different material systems of temperature‐responsive CLCs: small mesogenic molecules, PDLCs, PSLCs, and CLC polymers. For each system, examples of different device forms are presented, with their temperature responsiveness and the underlying mechanisms discussed. Additionally, the potential of each material system for future device applications and product developments is envisioned