School of Marine Science and Policy, College of Earth, Ocean and Environment, University of Delaware, Lewes, DE 19958, USA.
Talanta. 2011 Apr 15;84(2):374-81. doi: 10.1016/j.talanta.2011.01.025. Epub 2011 Jan 19.
A new spectrophotometric protocol was developed for the simultaneous determination of soluble Mn(III), Mn(II) and total Mn [sum of soluble Mn(III) and Mn(II)] in sediment porewaters using a water soluble meso-substituted porphyrin [α,β,γ,δ-tetrakis(4-carboxyphenyl)porphine (T(4-CP)P)]. A simple kinetic rate model is used to quantify soluble Mn(II), Mn(III) and total Mn concentrations during a metal substitution reaction. Under optimized conditions, the method accurately determines soluble Mn(II) and Mn(III) within a concentration range of 100 nM-10 μM. The detection limit of total soluble Mn is 50 nM. Using this method, soluble Mn(II) and Mn(III) concentrations were determined in standard solutions within 0.4-2% of the known values and agreed closely with results of inductively coupled plasma mass spectrometric and voltammetric analyses. The procedure was successfully applied to determine soluble Mn(II), Mn(III) and total Mn in sediment porewaters of the Lower St. Lawrence Estuary. Mn(III) represented up to 85% of the total soluble Mn pool in surface sediments.
采用水溶性中取代卟啉[α,β,γ,δ-四（4-羧基苯基）卟啉（T（4-CP）P）]，开发了一种新的分光光度法协议，用于同时测定沉积物孔隙水中的可溶性 Mn(III)、Mn(II)和总 Mn[可溶性 Mn(III)和 Mn(II)之和]。使用简单的动力学速率模型来量化金属取代反应过程中可溶性 Mn(II)、Mn(III)和总 Mn 的浓度。在优化条件下，该方法可在 100 nM-10 μM 的浓度范围内准确测定可溶性 Mn(II)和 Mn(III)。总可溶性 Mn 的检测限为 50 nM。使用该方法，在已知值的 0.4-2%范围内，标准溶液中的可溶性 Mn(II)和 Mn(III)浓度的测定值与电感耦合等离子体质谱和伏安分析的结果非常吻合。该程序成功应用于测定下圣劳伦斯河口沉积物孔隙水中的可溶性 Mn(II)、Mn(III)和总 Mn。Mn(III)在表层沉积物中的总可溶性 Mn 库中占比高达 85%。
