Synthesis of water-soluble polyamidoamines for biomedical applications. II. Polymers possessing intrachain-type secondary amino groups suitable for side-chain attachment

1993 ◽  
Vol 50 (3) ◽  
pp. 393-401 ◽  
Author(s):  
Gregg Caldwell ◽  
Eberhard W. Neuse ◽  
Andreas Stephanou
2015 ◽  
Vol 13 (39) ◽  
pp. 9969-9976 ◽  
Author(s):  
Ichiro Hayakawa ◽  
Tomomi Nakamura ◽  
Osamu Ohno ◽  
Kiyotake Suenaga ◽  
Hideo Kigoshi

(+)-Halichonine B and its analogues were synthesized, and their biological activities were evaluated. It was revealed that the secondary amino groups in the side chain portion are important for the strong cytotoxicity of halichonine B and that the N11-prenyl group is unimportant.


2020 ◽  
Vol 9 (1) ◽  
pp. 1118-1136
Author(s):  
Zhenjia Huang ◽  
Gary Chi-Pong Tsui ◽  
Yu Deng ◽  
Chak-Yin Tang

AbstractMicro/nano-fabrication technology via two-photon polymerization (TPP) nanolithography is a powerful and useful manufacturing tool that is capable of generating two dimensional (2D) to three dimensional (3D) arbitrary micro/nano-structures of various materials with a high spatial resolution. This technology has received tremendous interest in cell and tissue engineering and medical microdevices because of its remarkable fabrication capability for sophisticated structures from macro- to nano-scale, which are difficult to be achieved by traditional methods with limited microarchitecture controllability. To fabricate precisely designed 3D micro/nano-structures for biomedical applications via TPP nanolithography, the use of photoinitiators (PIs) and photoresists needs to be considered comprehensively and systematically. In this review, widely used commercially available PIs are first discussed, followed by elucidating synthesis strategies of water-soluble initiators for biomedical applications. In addition to the conventional photoresists, the distinctive properties of customized stimulus-responsive photoresists are discussed. Finally, current limitations and challenges in the material and fabrication aspects and an outlook for future prospects of TPP for biomedical applications based on different biocompatible photosensitive composites are discussed comprehensively. In all, this review provides a basic understanding of TPP technology and important roles of PIs and photoresists for fabricating high-precision stimulus-responsive micro/nano-structures for a wide range of biomedical applications.


RSC Advances ◽  
2015 ◽  
Vol 5 (116) ◽  
pp. 96189-96193 ◽  
Author(s):  
Markus Bender ◽  
Kai Seehafer ◽  
Marlene Findt ◽  
Uwe H. F. Bunz

We report the Pd-catalyzed synthesis of six new water soluble, alternating poly(p-phenylene-ethynylene-p-pyridinylene-ethynylene) (abcb-alternating) copolymers and one poly(p-pyridinyleneethynylene).


2001 ◽  
Vol 675 ◽  
Author(s):  
Jeong-Seo Park ◽  
Han-Chang Kang ◽  
Kurt E. Geckeler

ABSTRACTAs [60]fullerene is a very hydrophobic macromolecule, there have been a number of attempts to make it more hydrophilic for biomedical applications. By attaching hydrophilic moieties such as poly(oxyethylene)(POE) chains and cyclodextrin molecules to [60]fullerene, novel water-soluble and biocompatible materials have been successfully prepared [1,2].The synthesis of novel macrocyclic fullerene conjugates which are water-soluble is reported. The telechelic fullerene derivatives have been prepared via addition reaction of POE-based arms with covalently bonded β-cyclodextrin (CD) to [60]fullerene. To this end, a mono-tosylated CD derivative has been prepared in pyridine and then reacted with an amino-functional POE in the presence of triethylamine. The subsequent reaction of [60]fullerene with the hydrophilic POE-conjugated CD-derivative yielded the macrofullerene after separation and purification procedures.The macrocyclic [60]fullerene derivatives obtained were soluble in water and characterized by UV-VIS and FT-IR spectroscopy as well as light scattering measurements and thermogravimetric analysis.


Author(s):  
Rajiv Sharma ◽  
Vikram Jeet Singh ◽  
Pooja A Chawla

Background: The platinum (II) complexes as anticancer agents have been well explored for the development of novel analogs. Yet, none of them achieved clinical importance in oncology. At present, anticancer compounds containing platinum (II) complexes have been employed in the treatment of colorectal, lung, and genitourinary tumors. Among the platinum-based anticancer drugs, Cisplatin (cis-diamine dichloroplatinum (II), cis-[Pt(NH3)2Cl2]) is one of the most potent components of cancer chemotherapy. The nephrotoxicity, neurotoxicity and ototoxicity, and platinum compounds associated resistant cancer are some major disadvantages. Objective: With the rapidly growing interest in platinum (II) complexes in tumor chemotherapy, researchers have synthesized many new platinum analogs as anticancer agents that show better cytotoxicity, and less off-target effects with less cellular resistance. This follows the introduction of oxaliplatin, water-soluble carboplatin, multinuclear platinum and newly synthesized complexes, etc. Method: This review emphasizes recent advancements in drug design and development, the mechanism of platinum (II) complexes, their stereochemistry, current updates, and biomedical applications of platinum-based anticancer agents. Conclusion: In the last few decades, the popularity of platinum complexes as potent anti-cancer agents has risen as scientists have synthesized many new platinum complexes that exhibit better cytotoxicity coupled with less off-target effects.


2021 ◽  
Author(s):  
Salim Albukhaty ◽  
Hassan Al-Karagoly ◽  
alireza allafchian ◽  
Seyed Amir Hossein Jalali ◽  
Thair Alkelabi ◽  
...  

Abstract Electrospun polyvinyl alcohol and Tragacanth Gum were used to develop nanofibrous scaffolds containing poorly water-soluble beta-sitosterol. Different Concentration and Ratio of Polymeric composite: (10%) of β-S concentration in (PVA) 8 %, (TG) 0.5%, and 1% respectively were added, prepared and electrospun. The methods have included four parameters (Solution concentration, feeding rate, voltage, and distance of the collector to the tip of the needle) for designing and compared the nanofibers' average diameters. The nanofibers collected were identified via SEM, FTIR, and XRD measurements. A contact angle measurement described the hydrophilicity of the scaffold. MTT test was assessed for obtained nanofibers by using L929 normal fibroblast cells. The %age of mechanical strength, porosity, and deterioration of the scaffolds was well discussed. The average nanofibre ranged from 63 ± 20 nm to 97 ± 46 nm in diameters. The nanofibers loaded with β-S were freely soluble in water and displayed a short release lag time. The dissolution was related to an immediate dissolution, submicron-level recrystallization of β-S with sufficient conditions for nanofibers for L929 cell culture that could be used in biomedical applications. It concluded that electrospinning is a promising technique for poorly water-soluble β-S formulations that could be used in biomedical applications.


1988 ◽  
Vol 55 (4) ◽  
pp. 585-596 ◽  
Author(s):  
Anna Polychroniadou

SummaryA simple, rapid and sensitive spectrophotometric assay was developed and evaluated for monitoring proteolysis during cheese ripening, based on the fact that α-amino groups released by hydrolysis of cheese proteins react with trinitrobenzenesulphonic acid to form products that absorb strongly at 420 nm. A linear relationship was shown to exist between A420 and concentration of free α amino groups up to 0·5 HIM (r = 0·999, 38 df, P < 0·001). Repeatability of the method was satisfactory. The coefficient of variance was 0·53% for amino acid solutions and 1·19% for cheese extracts. Average recovery of glycine added to the cheese was 104 ± 2·9%. A comparison of the above method with that of determination of water-soluble N to total N ratio showed that there was good agreement between these two methods of assessment of proteolysis in cheese (r = 0·857, 32 df, P < 0·001). Mainly Feta and Teleme cheese were examined, but a similar correlation was obtained with hard Greek cheeses. Analytical conditions of the procedure are discussed.


Sign in / Sign up

Export Citation Format

Share Document