Rapid determination of 111 anti-infective drugs possibly added in cosmetics using high-performance liquid chromatography-tandem mass spectrometry with scheduled multiple reaction monitoring.

RATIONALE: Illegal addition of anti-infective drugs to cosmetics at low concentrations has been found. The illicit addition of anti-infective drugs encompasses a wide variety of medications. The current sample purification methods are inadequate to detect all these compounds. A sensitive, wide-coverage, and weak-matrix-effect measurement method needs to be established to address this issue. METHODS: Samples were extracted using acetonitrile, diluted 25 times, and then analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS) to detect 111 anti-infective drugs. The method was validated and assessed for matrix effect before being applied to cosmetic products. RESULTS: The calibration curves for the analytes exhibited a strong correlation coefficient (r > 0.995). The limit of detection ranged from 0.006 to 0.6 mg/kg. Matrix effects were significantly improved after a 25-fold dilution. The method was successfully applied to various cosmetics. Two of 82 samples tested contained lincomycin and miconazole, respectively. CONCLUSIONS: The developed method is quick and reliable to analyze anti-infective drugs in cosmetics, with potential for both qualitative and quantitative analyses. It is a valuable tool for cosmetic research and development, contributing to safer and more effective cosmetic products.

Screening for illegal addition of glucocorticoids in adulterated cosmetic products using ultra-performance liquid chromatography/tandem mass spectrometry with precursor ion scanning.

RATIONALE: The screening for illegal adulteration of glucocorticoids (GCs) in cosmetics is challenging due to the vast variety of potential GCs that are present to improve the declared effects. An effective analytical method to screen illegally added GCs in cosmetics is vital to protect consumers. METHODS: An ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) method using precursor ion scanning (PIS) acquisition mode was developed to screen GCs in cosmetics. Forty-seven GCs were investigated to identify their common product ions formed by collision-induced dissociation. Cosmetic samples spiked with GCs were extracted using solid-phase extraction. RESULTS: Four common positive product ions, m/z 121, 135, 147, and 171, were selected for PIS analysis. Limits of detection (LODs) were established for all 47 GCs. The method was validated on spiked samples to ensure its effectiveness in terms of sensitivity and selectivity. Sixty samples were analyzed. Seven GCs were detected in six samples. CONCLUSIONS: An effective screening method using UPLC/MS/MS with PIS acquisition mode was developed and successfully applied to screen for targeted and untargeted GCs in cosmetic samples.

[Research in rheological properties of four types of ophthalmic preparations].

This study is prepared to provide the basis of rheological parameters for the additional quality standard of ophthalmic gels, the rheological properties of the ophthalmic gels and the other three types of ophthalmic preparations. The medicines were compared through the study of the rheological properties for four types of ophthalmic preparations. The cone-plate rheometer was used to determine the dynamic and steady rheological parameters of four types of ophthalmic preparations. The similarities and differences of the measured results were analyzed to summarize the rheological indexes and parameters which are applied to distinguish the ophthalmic gels and the other types of ophthalmic preparations. 1 The elastic modulus should be greater than the viscous modulus for the ophthalmic gels in the range of the linear viscoelastic region. 2 The ophthalmic gels should be shear thinning non-Newtonian fluid with a certain yield stress and thixotropy. 3 The dynamic viscosity of the ophthalmic gels should be greater than 0.5 Pa·S at the temperature of 25 ℃ with the 50 s-1 shear rate. The typical rheological indexes and parameters of the ophthalmic gels were proposed in this article. The determination methods are simple and feasible. The rheological indexes and parameters have an important significance in the prescription design, production technology and quality control of the ophthalmic gels.

Generation of a human induced pluripotent stem cell line (FDCHi012-A) from a patient with DYRK1A-related intellectual disability syndrome carrying DYRK1A mutation (c.1024G > T).

DYRK1A haploinsufficiency causes a neurodevelopmental syndrome termed DYRK1A-related intellectual disability syndrome which is associated with a range of symptoms including microcephaly, epileptic seizures, and autism spectrum disorder. Here, we generated an induced Pluripotent Stem Cell (iPSC) line with a de novo missense mutation (DYRKIA c.1024G > T) from the peripheral blood mononuclear cells of a patient with DYRK1A-related intellectual disability syndrome. This iPSC line showed normal karyotype, exhibited pluripotency, and has three embryonic germ layers differentiation capacity. This iPSC line will be of great use in investigating the disease mechanisms and drug screening for patients with DYRK1A-related intellectual disability syndrome.

Characterization of unknown impurities in Coenzyme Q10 using LC-MS and NMR.

During studies on related substances in coenzyme Q10 (CoQ10) active pharmaceutical ingredient (API) and capsules, two impurities (Impurity 1 and Impurity 2) with each content more than 0.1% attracted our attention. Accelerated testing (40 °C /75%RH) and forced degradation of CoQ10 API and drug products in different stress conditions (base and heat) gave rise to the two unknown impurities. These unknown impurities were separated by reverse phase ultra-performance liquid chromatography (UPLC), where they were eluted at 0.77 (Impurity 1) and 1.10 (Impurity 2) relative retention times to CoQ10 peak. Impurity 2 was separated into two peaks (Impurity 2-1 and Impurity 2-2) by normal phase high performance liquid chromatography (NP-HPLC). In this study, an ultra-performance liquid chromatography complied with quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF/MS) via atmospheric pressure chemical ionization (APCI) was used to identify the proposed structure of the three impurities (Impurity 1, Impurity 2-1 and Impurity 2-2). We got the three impurities through preparative high performance liquid chromatography and their structures were further confirmed by 1D and 2D nuclear magnetic resonance (NMR). Based on the significance of these results, Impurity 1 was the impurity E referred in British Pharmacopoeia (BP), Impurity 2-1 and Impurity 2-2 were a pair of isomers which had not been reported before.