Rapid Visual Detection of Spiroplasma eriocheiris by Loop-Mediated Isothermal Amplification with Hydroxynaphthol Blue Dye.

In recent years, a new type of Spiroplasma has been found that can cause "tremor disease" of the Chinese mitten crab Eriocheir sinensis. The outbreak of epidemic tremor disease has caused a serious setback in the Chinese mitten crab farming industry, with an incidence rate of more than 30% and mortality rates of 80-100%. Therefore, finding a sensitive method to detect tremor disease in E. sinensis has become a current research focus. In this research, a loop-mediated isothermal amplification detection method coupled with hydroxynaphthol blue dye (LAMP-HNB) was developed and used to rapidly detect Spiroplasma eriocheiris. First, we designed and synthesized specific outer primers, inner primers and loop primers based on the 16S ribosomal RNA gene of S. eriocheiris. Second, the LAMP-HNB detection method for S. eriocheiris was successfully established by screening the primers, adjusting the temperature and time of the reaction, and optimizing the concentrations of Mg2+ and dNTPs. In the specific tests, only samples infected with S. eriocheiris showed positive results, and other infections caused by bacteria and parasites tested negative, proving that the test has high specificity. Moreover, the detection limit was 2.5 × 10-6 ng/µL, indicating high sensitivity. This method for detecting S. eriocheiris provides rapid visual output based on LAMP-HNB detection and is a simple, fast, sensitive, and inexpensive method that can be applied to a wide range of field investigations.

Metal-free aminofluorination of α-diazo 2H-benzopyran-4-one: convenient access to ß-fluoramides.

We have developed a convenient synthesis of a series of ß-fluoramides in 65% yield. The process involved a tandem fluorination/Ritter reaction to synthesize ß-fluoramides using α-diazo 2H-benzopyran-4-one compounds. Selectfluor was used as the electrophilic fluoride source in acetonitrile to build the ß-fluorinated quaternary carbon center and amide derivatives of 2H-benzopyran-4-one in one step. The products N-(2-(2-fluoro-2,3-dihydro-3-oxobenzofuran-2-yl)propan-2-yl)acetamides were a series of bifunctional compounds with a 2-fluoro-2,3-dihydro-3-oxobenzofuran motif and amide groups.