Explore chapters and articles related to this topic
The Modification of Lysine
Published in Roger L. Lundblad, Chemical Reagents for Protein Modification, 2020
Succinic anhydride has also proved useful in the modification of lysine.41 Modification of lysine residues with succinic anhydride results in charge reversal. Reaction with succinic anhydride frequently results in the dissociation of multimeric proteins and has also been used to “solubilize” insoluble proteins. Meighen and co-workers42 have produced a “variant” form of bacterial luciferase through reaction with succinic anhydride. The succinylated protein retained the dimeric subunit structure of the native enzyme. By complementation experiments involving the mixing/hybridization of the modified and native enzyme, it was determined that succinylation of bacterial luciferase resulted in the inactivation of the α-subunit without markedly affecting the function of the β-subunit. Shetty and Rao43 studied the reaction of succinic anhydride with arachin. In this study, reaction of the protein was performed in 0.1 M sodium phosphate, pH 7.8, with the pH maintained over the course of the reaction by the addition of 2.0 M NaOH. The extent of modification was determined by reaction of the unmodified primary amino groups on the protein with trinitrobenzenesulfonic acid (see below). With a 200:1 molar excess of succinic anhydride, 82% of the available amino groups were succinylated with concomitant dissociation of the subunits of this protein. The reaction of chymotrypsinogen with succinic anhydride has been studied.44 In these experiments, the reaction was performed under ambient conditions in 0.05 M sodium phosphate, pH 7.5. During the course of the reaction the pH was maintained at 7.5 by the addition of 1.0 M NaOH. Chymotrypsinogen (1 g) was dissolved in the sodium phosphate buffer and 50 mg of succinic anhydride was added over a 30-min period. Under these conditions, 8 of the 14 lysine residues were modified. A related reaction involves the trimesylation of amino groups in proteins (see Figure 7).45 This reaction involves the modification of the protein with di(trimethysilyethyl)trimesic acid. Removal of the blocking groups results in an extremely polar derivative. The procedure is suggested to have value in the solubilization of membrane proteins.
NanoMIL-100(Fe) containing docetaxel for breast cancer therapy
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Mahsa Rezaei, Alireza Abbasi, Reyhaneh Varshochian, Rassoul Dinarvand, Mahmood Jeddi-Tehrani
All chemicals in this work were purchased from commercial vendors and were applied without further purification. FeCl3.6H2O (Merck), 1,3,5-Benzene carboxylic acid or trimesic acid (1,3,5-BTC, Merck), hydroflouric acid (HF, Chem-Lab), nitric acid (HNO3, Merck), dichloromethane (DCM), docetaxel (DTX, Sanofi), polysorbate 80 (Merck), hydrochloric acid (HCl, Merck), dimethyl sulphoxide (DMSO, Merck) and HPLC-grade methanol and acetonitrile were provided from DaeJung. Also, foetal bovine serum (FBS), 3–(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), penicillin, 0.25% trypsin-ethylenediaminetetraacetic acid (EDTA) and Dulbecco's modified eagle medium (DMEM) cell culture medium were all purchased from Sigma–Aldrich (St. Louis, MO). MCF-7 human breast adenocarcinoma cells were obtained from national cell bank of Iran (NCBI).
One-pot synthesis of Eu-MOFs for bioimaging and drug delivery
Published in Drug Development and Industrial Pharmacy, 2021
Qian Zhang, Jun Li, Wen Zu, Haisen Yang, Yuewu Wang
SEM was used to assess the morphological characteristics of prepared Eu-MOFs and Eu-MOFs/PTX, revealing them to exhibit a uniform particle size and to be highly dispersed, with a topographic appearance similar to that of a sea urchin (Figure 2(A,C)). When the small molecule drug PTX was loaded into these Eu-MOFs, their morphology was unchanged (Figure 2(B,D)), and they retained their original crystal structure as suggested by the associated XRD patterns (Figure 3). These particles were synthesized to serve as biomimetic drug delivery systems (BDDSs), as such nanocarrier platforms have been shown to exhibit low immunogenicity and good targeting efficiency. The sea urchin-like Eu-MOFs polymer spines are thought to promote its better availability and prolonged in vivo circulation, making such MOFs of greater value in the context of antitumor treatment [37]. Appropriate drug carrier selection is vital to overcome the poor solubility of many small molecule compounds in aqueous solutions. The fluorescent properties of these Eu-MOFs were also robust, highlighting their potential utility in fluorescent bioimaging applications. XRD analyses also confirmed that our Eu-MOFs and Eu-MOFs/PTX had been synthesized successfully. Evidently, PTX loading had almost no impact on the crystalline integrity, as evidenced by the fact that the dominant peaks in the XRD spectrum of Eu-MOFs/PTX were well correlated with those of the Eu-MOFs pattern (Figure 3). Eu-MOF FT-IR spectra were additionally generated (Figure 4), with 1,3,5-trimesic acid (H3BTC) exhibiting characteristic peaks at 1453 and 1399 cm−1 consistent with the asymmetric and symmetric stretching vibrations of –COOH (Figure 4(A)), while the 1108 cm−1 peak was attributable to the C–H vibration of the aromatic rings. The Eu(NO3)·6H2O spectra additionally exhibited a peak at 1047 cm−1 attributable to NO3– stretching vibrations (Figure 4(B)). As the FT-IR spectra of prepared Eu-MOFs exhibited these characteristic H3BTC and Eu(NO3)·6H2O peaks, this confirmed that we had successfully synthesized these nanocarriers (Figure 4(C)).