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A range of 5,15-diphenylporphyrins with symmetric and unsymmetric substitution patterns were subjected to osmium tetroxide-mediated dihydroxylations. The resulting chlorins and bacteriochlorins present an important group of compounds for studying structure-activity relationships of photodynamic sensitizers. The regioselectivity of the dihydroxylation of various 5,15-diphenylporphyrins with unsymmetrical substitution patterns was also examined. Both diphenylchlorin diol (DPC) and diphenylbacteriochlorin tetrol (DPBC) examples were converted into reactive isothiocyanates and conjugated with bovine serum albumin (BSA).

A novel, direct technique has been developed to measure the interactions of bovine serum albumin (BSA) on surfaces by using atomic force microscopy (AFM) in a liquid environment. We have been able to measure adhesion forces between proteins and substrate surfaces in phosphate-buffered saline (PBS) solution directly, without any modification to the substrate and the AFM tip. Two different surfaces have been used in the measurements: mica (hydrophilic surface) and polystyrene (hydrophobic surface). The results show that a polystyrene surface has larger adhesion forces to BSA than a mica surface. This is consistent with previous research, which demonstrated that hydrophobic surfaces enhance protein adhesion but hydrophilic surfaces do not.

Iron oxide nanoparticles were prepared and functionalized by succinamide based dendrimer. The resultant particles were characterized by XRD, VSM, and FTIR spectroscopy. The results indicate that the dendrimers has effectively functionalized the magnetite nanoparticles which remain dispersive and exhibited super-paramagnetism with a magnetization value of 33.2 emu/g in a field of 2T. Mean particle size as calculated from the AFM was found to be ~ 23 nm. Bovine serum albumin was immobilized on the magnetic nanoparticles as was confirmed by the FTIR results.

The binding interaction mechanism between 5-phenyl-10,15,20-tri-(4-pyridyl)-porphyrin (TriPyP) and bovine serum albumin (BSA) was investigated by the fluorescence method and presented in this paper. Based on the mechanism of fluorescence quenching of BSA caused by TriPyP, the binding constants between TriPyP and BSA were measured at different temperatures by fluorescence spectroscopy at pH 7.40. As the binding constants decreased with increasing temperature, the type of quenching between TriPyP and BSA was determined as static quenching. Based on the Förster theory of non-radiation energy transfer, the binding distance and energy transfer efficiency at 25 °C between TriPyP (acceptor of energy) and BSA (donor of energy) were obtained. The results confirmed that the interaction was similar to non-radiation energy transfer. According to the thermodynamic parameters, the main type of binding force between TriPyP and BSA could be deduced as electrostatic force. Using synchronous fluorescence spectra, the effect of TriPyP on conformation of BSA was studied, and the hydrophobicity in microenvironment was developed by TriPyP. All these experimental results and theoretical data clarified that TriPyP could bind to BSA and be effectively transported in the human body, which could be a useful guideline for further drug design.

The interaction of meso-tetra-($N$-methyl-3-pyridyl)bacteriochlorin tetra 4-methylbenzenesulfonate, meso-tetra-($N$-methyl-4-pyridyl)porphine tetraiodide and meso-tetra-($N$-methyl-3-pyridyl)porphine tetraiodide with protein was studied. The localization of macrocycles in the protein and their influence on the processes of protein aggregation were established. The aggregation process is initiated by the transition of alpha structures into beta folds, caused by the binding of porphyrins at the sites of protein IB and IIA. The complexes were irradiated with blue and green light. The data obtained showed that by varying the intensity of the light exposure, one can influence the shift of the aggregation equilibrium, obtaining predominantly monomeric or aggregated structures. Thus, photoexposure can be used as an alternative method of treating diseases caused by amyloidosis and for regulating the state of the protein in the pharmacological preparations.

In recent years, graphene biosensors have received much attention due to their high sensitivity, low noise and low detection limit. Vertical graphene field effect transistors (VGFETs) based on graphene/semiconductor heterojunctions are characterized by high switching ratios and have wide application prospects. In this study, we prepared the ion-gel gate VGFETs and used them for bovine serum albumin (BSA) quantification sensors. The results showed that the adsorption of BSA molecules on the substrate surface was maximized when the ionic strength was 10${}^{-3}$M. The limit of detection (LOD) of BSA concentration was 1$\mu$g/ml, suitable for simple and rapid quantitative analysis of protein molecules.

The binding interaction between tetra-(p-sulfoazophenyl-4-aminosulfonyl)-substituted aluminum (III) phthalocyanine (AlPc), and two-serum albumins (bovine serum albumin (BSA) and human serum albumin (HSA)) has been investigated. AlPc could quench the intrinsic fluorescence of BSA and HSA through a static quenching process. The primary and secondary binding sites of AlPc on BSA were domain I and III of BSA. The primary binding site of AlPc on HSA was domain I, and the secondary binding sites of AlPc on HSA were found at domains I and II. Our results suggest that AlPc readily interact with BSA and HSA implying that the amphiphilic substituents AlPc may contribute to their transportation in the blood.

Discrete biomolecule-nanoparticle (NP) conjugates play paramount roles in nanofabrication, in which the key is to get the precise molar extinction coefficient of NPs. By making best use of the gift from a specific separation phenomenon of agarose gel electrophoresis (GE), amphiphilic polymer coated NP with exact number of bovine serum albumin (BSA) proteins can be extracted and further experimentally employed to precisely calculate the molar extinction coefficient of the NPs. This method could further benefit the evaluation and extraction of any other dual-component NP-containing bio-conjugates.

A novel and cost-effective 2,4-dinitrophenyl hydrazine derived from Schiff base 1-benzylidine-2-(2,4-dinitrophenyl) hydrazine ( L) was designed and characterized using various spectroscopic techniques. The interaction between L and bovine serum albumin (BSA) has been carried out using UV–Vis and fluorescence spectroscopy, DSC, SEM, and molecular docking methods. The phosphate buffer ($\mathrm{\text{pH}}=7.4$) solution of BSA showed fluorescence emission maxima at 342nm. Upon addition of L to the BSA solution, it quenched the fluorescence emission at 342nm. The quenching of the fluorescence emission is due to the formation of a complex between L and BSA. The binding constant was calculated from the fluorescence titrations and found to be $6.745\times 10^6$M${}^{-1}$. Further, molecular docking analysis was carried out to establish the binding between L and BSA.