Publications by authors named "Eunice Suenaga"

A new, rapid, selective and sensitive UPLC-MS/MS method was developed and validated for the quantification of (-) - hydroxycitric acid (HCA) in human plasma, using DL-malic acid-2,3,3-d3 as internal standard (IS) and simple protein precipitation for the sample preparations. HCA is a highly polar compound make challenging its determination in biological fluids. A specific chromatography column Acquity UPLC HSS T3 (100 × 2.

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Purpose: To compare the aqueous humor (AH) concentrations of moxifloxacin 0.5% and gatifloxacin 0.3% solutions alone or when treatment was combined with steroids, and to correlate these concentrations with the minimum inhibitory concentrations (MIC) for the most common endophthalmitis-causing organisms.

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Purpose: To compare aqueous humor concentrations of topically applied moxifloxacin 0.5% ophthalmic solution alone or in combination with dexamethasone 0.1% and to correlate these concentrations with the minimum inhibitory concentrations (MICs) for common endophthalmitis-causing organisms.

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We have developed and validated a fast and sensitive ultra high-performance liquid chromatography with positive ion electrospray ionization tandem mass spectrometry method for determining N-butylscopolamine levels in human plasma using propranolol as an internal standard. The acquisition was set up in the multiple reaction monitoring mode with the transitions m/z 360.3 → 138.

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A new automated SPE-LC-ESI-MS/MS method was developed and validated to quantify venlafaxine in human plasma using fluoxetine as an internal standard. The analytes were automatically extracted from plasma by C18 SPE cartridges, separated on a C8 RP column and analyzed by MS in the multiple reaction-monitoring (MRM) mode. The method has a chromatographic run time of 4.

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HPLC stability-indicating method was validated for Vitamin C (ascorbic acid) in semisolid pharmaceutical/cosmetic formulations containing glutathione and sodium metabisulfite, as antioxidants. The described procedure included a reliable, precise, accurate and specific method determination employing a 250mm x 4.6mm C(18) column, 0.

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Article Synopsis
  • Vitamin C plays a crucial role in skin health through collagen synthesis, depigmentation, and antioxidant effects, but it is highly unstable in various conditions, necessitating effective antioxidant systems for stability in cosmetic products.
  • The research aimed to develop O/W emulsions and aqueous gels containing vitamin C, testing the effects of antioxidants sodium metabisulfite (SMB) and glutathione (GLT) on its stability.
  • Stability tests showed that formulations with SMB or GLT maintained over 90% of vitamin C content under controlled conditions, confirming that these antioxidants are essential for preserving vitamin C in cosmetics.
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