Metalloporphyrin molecular size

Biggs and co-workers used a DC arc plasma detector to measure iron, nickel, vanadium, and sulfur profiles from SEC of petroleum and its distillation and adsorption chromatography fractions [118-123]. They found that the metal species were present as three distinct molecular sizes. They identified the low molecular weight ones as metalloporphyrins. They also measured the variety of siliconpolysiloxane polymers and synthetic alkyl- and arylsulfonates [124]. 

Porphyrin-based self-assembled molecular squares 389 can form mesoporous thin films in which the edge of a square, thus the size of the cavity, can be adjusted by appropriate choice of substituents [8]. Fibers that form coil-coiled aggregates with distinct, tunable helicity are built from crown ethers bearing porphyrins 390 [9]. In addition to the porphyrin applications discussed in Sections 6.3.2.2 and 6.4, dendrimer metalloporphyrins 391 to be applied in catalysis [10] and the water-soluble dendritic iron porphyrin 319 modelling globular heme proteins [11] can be mentioned. 

Metal nanoparticles have extraordinary size-dependent optical properties, not present in the bulk metal and have, consequently, been the subject of intense research during the past decade or so.27 Attention has recently focused on functionalising colloidal nanoparticles with molecular recognition components for potential sensing applications.28,29,30 We have prepared a new amido-disulfide functionalised zinc metalloporphyrin (8) which was self-assembled on to gold nanoparticles to produce a novel anion-selective optical sensing system (9) (Scheme 3).4... 

The incorporation of vitamin B12 derivatives into plasticized poly(vinyl chloride) membranes has resulted in the development of several ion-selective electrodes (ISEs). The response of the electrodes has been related to principles of molecular recognition chemistry. In addition, ISEs have been prepared by electropolymerization of a cobalt porphyrin. These electrodes have selectivity properties that are controlled by both the intrinsic selectivity of the metalloporphyrin and the characteristics of the polymer film (e.g., pore size). 

The geometry of metalloporphyrins and other tetrapyrroles have been studied in detail by molecular mechanics. The effect of (i) the size of the metal ion, (ii) axial ligation by planar ligands, such as imidazoles, (iii) the phenyl group orientation in tet-raphenyl porphinato complexes, and (iv) the flexibility of the porphyrin macrocycle,... 

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