Unconsumed precursors and couplers after formation of oxidative hair dyes

Contact allergy to hair dye ingredients, especially precursors and couplers, is a well-known entity among consumers having hair colouring done at home or at a hairdresser. The aim of the present investigation was to estimate consumer exposure to some selected precursors (p-phenylenediamine, toluene-2,5-diamine) and couplers (3-aminophenol, 4-aminophenol, resorcinol) of oxidative hair dyes during and after hair dyeing. Concentrations of unconsumed precursors and couplers in 8 hair dye formulations for non-professional use were investigated, under the conditions reflecting hair dyeing. Oxidative hair dye formation in the absence of hair was investigated using 6 products, and 2 products were used for experimental hair dyeing. In both presence and absence of hair, significant amounts of unconsumed precursors and couplers remained in the hair dye formulations after final colour development. Thus, up to 1.1% p-phenylenediamine (PPD), 0.04% toluene-2,5-diamine, 0.02% 3-aminophenol and 0.02% resorcinol were found in the hair dye formulation after the required colour was developed. The consumers are thus exposed to precursors and couplers of oxidative hair dyes, both during and after hair dyeing, when the hair is washed. Furthermore, the consumers are also expected to be exposed to intermediates of oxidative hair dyes. The allergenic potential of oxidative hair dyes as well as the intermediates of these remains unknown.     

HPLC法同时测定足菌清中水杨酸等4种成分的含量

用反相高效液相色谱法同时分离测定足菌清中水杨酸、苯甲酸、间苯二酚及呋喃西林的含量。水杨酸、苯甲酸、间苯二酚的线性为 0 15～ 0 75 g/L,r值分别为 0 9998、0 9999、0 9997;呋喃西林的线性为 0 0 0 72～ 0 0 36 g/L,r =1 0 0 0 ;平均回收率 (X±RSD) %分别为 ,水杨酸 (99 9±2 4) % ,苯甲酸 (10 0 1± 1 9) % ;间苯二酚 (99 7± 2 8) % ;呋喃西林 (10 0 9± 3 0 ) %。     

褶合光谱法测定复方间苯二酚搽剂中苯酚间苯二酚的含量

本文采用褶合光谱法,在不经分离的条件下,同时测定苯酚、间苯二酚的含量,平均回收率(ER)和相对平均偏差(RSD)分别为:99.44％,1.44％;99.64％,0.41％。     

高效液相色谱法测定复方间苯二酚搽剂中间苯二酚、水杨酸及醋酸氟轻松的含量

目的 建立高效液相色谱(HPLC)法测定复方间苯二酚搽剂中间苯二酚、水杨酸和醋酸氟轻松的含量.方法 采用HPLC法.色谱柱为WondaSil C18(250 mm×4.6 mm,5μm),流动相组成为甲醇-乙腈-0.1%磷酸溶液(55:10:35),流速为1.0 mL·min-1,柱温为30℃,紫外检测器波长:240 nm,进样量:10μL.结果 间苯二酚、水杨酸和醋酸氟轻松检测质量的线性范围分别为16~56、10~35和0.08~0.28μg;精密度、稳定性、重复性试验的RSD≤0.50%;平均加样回收率分别为99.05%(n=6,RSD=0.70%)、100.16%(n=6,RSD=0.63%)和99.20%(n=6,RSD=0.81%).结论 该方法结果准确,精密度高,可同时测定间苯二酚、水杨酸和醋酸氟轻松的含量,可用于此制剂的质量控制.     

Green microparticles based on a chitosan/lactobionic acid/linoleic acid association. Characterisation and evaluation as a new carrier system for cosmetics

The association chitosan/linoleic acid/lactobionic acid in aqueous solution spontaneously led to the formation of stable microparticles with a liquid hydrophobic core consisting of linoleic acid surrounded by a shell of chitosan/lactobionic acid. The originality of the microparticles arises from the fact that they are formed by the association of three ingredients of cosmetic interest, including a skin penetration enhancer (linoleic acid). Dynamic light scattering (DLS) measurements showed microparticles with a mean diameter of 1–2?μm. The presence of a hydrophobic liquid core was observed by transmission electron microscopy (TEM). The ability of these microparticles to encapsulate phenylethyl resorcinol, a hydrophobic skin lightener, was evaluated and its encapsulation was confirmed thanks to T₂ measurements and nuclear Overhauser effects (nOe) signs.     

高效液相色谱法同时测定黄芪赤风胶囊中芍药苷、升麻素苷等9种成分的含量

 目的 建立HPLC同时测定黄芪赤风胶囊中9种成分的含量。方法 采用Waters Symmetry Shield RP₁₈（4.6 mm×150 mm,5 μm）色谱柱;以甲醇（A）-水溶液（B）为流动相进行梯度洗脱（0～15 min,5%A→20%A;15～55 min,20%A→35%A;55～100 min,35%A→85%A）,流速1.0 mL·min^-1;检测波长：230 nm（0～25 min,芍药苷）,254 nm（25～100 min,毛蕊异黄酮苷等）;柱温35 ℃。结果 芍药苷、升麻素苷、毛蕊异黄酮苷、升麻素、5-O-甲基维斯阿米醇苷、芒柄花苷、亥茅酚苷、毛蕊异黄酮、芒柄花素的线性范围分别为1.51～15.10,0.047～0.94,2.192～10.960,0.052 2～1.044,0.041 4～0.828,1.56～7.80,0.042 2～0.844,0.149～0.744和0.110～0.552 μg（r≥0.999 0）;平均回收率（n=6）分别为99.48%（RSD=2.59%）,103.15%（RSD=1.69%）,102.77%（RSD=1.56%）,99.27%（RSD=2.72%）,101.99%（RSD=2.36%）,102.25%（RSD=2.10%）,101.49%（RSD=3.00%）,100.45%（RSD=1.76%）和97.49%（RSD=2.03%）。结论 所建立的方法快速、准确、专属性强、精密度好,可用于黄芪赤风胶囊的质量控制。     

锌制剂的PAR—CTMAB比色测定法

对测定锌制剂含量的PAR-CTMAB比色法进行了研究。本法简便、快速,结果准确,重现性好,线性范围宽(0.08～1.2μg/ml),且干扰小,回收率为100.1±0.25%。本法同中国药典法比较,测定结果经F、t 测验无显著差异。     

The skin sensitization potential of resorcinol: experience with the local lymph node assay

Resorcinol is a simple aromatic chemical (1,3-benzenediol) that has found widespread use, particularly as a coupler in hair dyes. Clinical experience clearly shows that resorcinol is a (albeit uncommon) skin sensitizer. By contrast, predictive methods, both animal and human, have previously failed to identify resorcinol as such. Here, we describe the outcome of a recent local lymph node assay performed in accordance with Organisation for Economic Co-operation and Development guideline 429, which correctly identified resorcinol as a skin sensitizer. Clear evidence of a dose response was apparent, and an EC3 value of approximately 6% was calculated. This suggests that the skin-sensitizing potency of resorcinol is approximately 2 orders of magnitude lower than that of p-phenylenediamine but similar to that of hexyl cinnamic aldehyde. These data show the importance of adherence to test guidelines and aligns the clinical experience with resorcinol with that obtained in predictive animal methods.     

A potential in vitro epidermal equivalent assay to determine sensitizer potency

Most in vitro assays aim to distinguish sensitizers from non-sensitizers. Few aim to classify sensitizers according to potency. Here, we describe a potential method for classifying sensitizers according to their irritant potency with the aid of in house epidermal equivalents (EE). Sixteen sensitizers were applied topically in a dose response to EE for 24 h. The EE-EC₅₀ value (effective chemical concentration required to reduce cell viability by 50%) and the EE-IL-1α_10× value (chemical concentration which increases IL-1α secretion by 10-fold) were calculated. From 16 sensitizers, EE-EC₅₀ and/or EE-IL-1α_10× values were obtained from 12 skin sensitizers. EE-EC₅₀ and IL-1α_10× values decreased in proportion to increasing sensitizer potency. The in vitro assay correlated with existing in vivo mouse and human sensitization data (LLNA, HRIPT), and showed low intra- and inter-experimental variability. Additionally DNCB and resorcinol were correctly assessed as extreme and moderate sensitizers using commercial EE (EST1000™ and RHE™). In conclusion, our data supports the view that irritancy may in part be a factor determining sensitizer potency. Since this assay does not distinguish sensitizers from non-sensitizers, its potential application is in a tiered strategy, where Tier 1 identifies sensitizers which may then tested in Tier 2, this assay, which determines sensitizer potency.