Characterization, Direct Electrochemistry, and Amperometric Biosensing of Graphene by Noncovalent Functionalization with Picket‐Fence Porphyrin

Abstract

Reduced graphene oxide (RGO) was prepared and functionalized with picket-fence porphyrin, 5,10,15,20-tetrakis [αααα-2-trismethylammoniomethylphenyl] porphyrin iron(III) pentachloride (FeTMAPP), through π-π interactions. The resulting nanocomposite was characterized by atomic force microscopy (AFM); transmission electron microscopy (TEM); contact angle measurements; and fluorescence, Raman, and UV/Vis absorption spectroscopy. On account of the introduction of positively charged FeTMAPP, the functionalized RGO showed good dispersion in aqueous solution. The RGO could greatly accelerate the electron transfer of FeTMAPP to produce a well-defined redox couple of Fe(III)/Fe(II) at -0.291 and -0.314 V. Due to the synergic effect between RGO and the porphyrin, the nanocomposite showed excellent electrocatalytic activity toward the reduction of chlorite, thus leading to highly sensitive amperometric biosensing at low applied potential. The biosensor for chlorite showed a linear range from 5.0×10(-8) to 1.2×10(-4) mol L(-1) with a detection limit of 2.4×10(-8) mol L(-1) at a signal-to-noise ratio of 3. The picket-fence porphyrin could serve as an efficient species to functionalize graphene for electronic and optical applications.

Photoelectrochemistry of Free‐Base‐Porphyrin‐Functionalized Zinc Oxide Nanoparticles and Their Applications in Biosensing

“…Metalloporphyrins such as iron-porphyrin, cobalt-porphyrin, and manganese-porphyrin exhibited good electrocatalysis toward many small molecules related to life processes. [15][16][17] However, their photochemical and photoelectrochemical applicaAbstract: The photoelectrochemical properties of free-base-porphyrin-functionalized zinc oxide nanoparticles were studied. A universal photoelectrochemical biosensing platform was constructed on indium tin oxide (ITO) by using the functional nanohybrid.…”

Graphene for Detection of Adenosine Triphosphate, Nicotinamide Adenine Dinucleotide, Other Molecules, Gas, and Ions

“…Graphene sheets also serve as good substrates for various other molecule detection, including acetylcholine/choline [42], cholesterol [43], benzenediol isomers (hydroquinone, resorcinol, catechol) [44], epinephrine [45], aromatic molecules (crystal violet, amaranth, phosphorus triphenyl [46], and rhodamine 6G, rhodamine B, methyl violet, methylene blue [47]), folic acid [48], naphthalene and 1-naphthol [49], malachite green [50], microcystin-LR [51], cocaine/adenosine [52], pyrogallol [53,54], nitric oxide [55], urea [56], hydrazine [57], nitrophenol [58], catechol [59], hypoxanthine [60], chlorite [61], paraoxon [62,63], phenol [64], heparin [65,66], trinitrotoluene (TNT) [67,68], bleomycin [69], ochratoxin A, and fumonisin B 1 [70].…”

One-pot synthesis of manganese porphyrin covalently functionalized graphene oxide for enhanced photocatalytic hydrogen evolution

“…The calculated quenching efficiency is about 89.4%. The high quenching efficiency of GO-MnTPP indicates the occurrence of photo-induced intramolecular electrons transfer between GO and MnTPP moieties [56].…”