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CRISPR/Cas9 systems have great potential to achieve sophisticated gene therapy and cell engineering by editing multiple genomic loci. However, to achieve efficient multiplex gene editing, the delivery system needs adequate capacity to transfect all CRISPR/Cas9 RNA species at the required stoichiometry into the cytosol of each individual cell. Herein, inspired by biomineralization in nature, we develop an all-in-one biomimetic mineralized CRISPR/Cas9 RNA delivery system. This system allows for precise control over the coencapsulation ratio between Cas9 mRNA and multiple sgRNAs, while also exhibiting a high RNA loading capacity. In addition, it enhances the storage stability of RNA at 4 °C for up to one month, and the surface of the nanoparticles can be easily functionalized for precise targeting of RNA nanoparticles in vivoat nonliver sites. Based on the above characteristics, as a proof-of-concept, our system was able to achieve significant gene-editing at each target gene (Survivin: 31.9%, PLK1: 24.41%, HPV: 23.2%) and promote apoptosis of HeLacells in the mouse model, inhibiting tumor growth without obvious off-target effects in liver tissue. This system addresses various challenges associated with multicomponent RNA delivery in vivo, providing an innovative strategy for the RNA-based CRISPR/Cas9 gene editing.

The combined use of modified QuEChERS extraction and ultra high-performance chromatography-tandem mass spectrometry (UHPLC-MS/MS) for determining all seven triazolopyrimidine sulfonamide herbicides in cereals (wheat, rice, and corn), soybean and soil was developed. The seven herbicides (metosulam, flumetsulam, pyroxsulam, florasulam, diclosulam, cloransulam-methyl and penoxsulam) were extracted using acetonitrile from five matrices, and then cleaned up using octadecylsilane or Florisil prior to UHPLC-MS/MS. The method has excellent linearity (R2≥ 0.996). The average recoveries in wheat, rice, corn, soybean and soil at three spiked concentrations (0.005, 0.010 and 0.10 mg kg−1) ranged from 73.8% to 113.2% with all RSD values less than 17.5%. The LOQs for seven herbicides were 0.005 mg kg−1in cereals, soybean and soil. This method has been demonstrated to be reliable and convenient for monitoring triazolopyrimidine sulfonamide herbicides.

A rapid, sensitive and selective method for determining phthalanilic acid residue in bean, fruits and vegetables based on a modified quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction procedure was developed by ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS). The samples were extracted by acidified acetonitrile (0.4% (v/v) formic acid) and simultaneous liquid–liquid partitioning formed by adding anhydrous magnesium sulfate (MgSO4) and sodium chloride (NaCl). The extract was then cleaned up by dispersive-SPE using florisil and graphitized carbon black (GCB) as selective sorbent. Parameters including the matrix effect, linearity, precision, accuracy and stability were undertaken. The method showed good linearity in the concentration range of 10–1000 μg L−1, with correlation coefficients ≥0.997. Recovery studies were performed at three fortification levels of 10, 100 and 1000 μg kg−1in soybean, apple, grape, cucumber, tomato and pepper. Further optimization of sample preparation and determination achieved recoveries ranging between 70.1% and 105.3% for the analyte with 0.7–14.9% intra-day relative standard deviations (RSD) and 0.2–8% inter-day RSD at three spiked levels (10, 100 and 1000 μg kg−1). The limits of detection (LOD) were below 1 μg kg−1, and the limits of quantification (LOQ) did not exceed 3 μg kg−1. The effects of two columns on the separation were also investigated. The method is demonstrated to be convenient and reliable for determination of phthalanilic acid in bean, fruits and vegetables. With the developed method, 60 samples of commercial fruit products (grape, apple), soybean and vegetables (pepper, tomato, cucumber) were analyzed. Phthalanilic acid was not detected in all samples.