Steroid-Based Supramolecular Systems and their Biomedical Applications: Biomolecular Recognition and Transportation

In this chapter, the biomedical application of steroid-based compounds at “beyond the molecule”—supramolecular level—is reviewed. The renewable and economic natural steroid compounds could be employed as building blocks in the design and construction of steroid-based supramolecular systems. The specific physicochemical features (size, shape, topology, hydrophobicity, chemical modifiability, etc.) and biological properties (biocompatibility, biodegradability, bioaffinity, etc.) could be integrated into functional supramolecular systems by chemical synthesis, modification and intermolecular interactions (such as hydrogen bonding, π-π stacking, van der Waals forces, inclusion interactions, chiral interactions, electrostatic interactions, and so on). The steroid-based (supra)molecules could be employed for molecular recognition and/or be self-assembled into various functional supramolecular assemblies for biomedical applications. The specific physicochemical and biological properties, good biocompatibility, and biological activity endow the steroid-based supramolecular systems good feasibility to be employed in biomolecular recognition/sensing and biomolecular transportation (gene/drug delivery). The examples in this chapter are exemplificative of the transformation of natural steroid-based compounds into functional steroid-based supramolecular systems through molecular and supramolecular engineering technology, moreover, which may inspire the systematic study of natural product-based supramolecular (nano)materials toward future pharmaceutical and biomedical industry

Chemical sensors towards environmental toxic molecule monitoring: fluorescent probes for detection of thiophenol

Thiophenols, a family of important industrial chemicals, is highly toxic for aquatic organisms and human beings. Developing new chemical sensors with the merit of fast, low cost, portable, selective and sensitive, as well as visualizable signal output for efficient detection of thiophenols, is highly desirable. This spotlight article reviewed and discussed the current trend and statement of thiophenols-specific fluorescent probes. Moreover, the future outlook in this field was also stated.info:eu-repo/semantics/publishedVersio

A dual-analytes responsive fluorescent probe for discriminative detection of ClO− and N2H4 in living cells

Hydrazine (N2H4) and ClO− are very harmful for public health, hence it is important and necessary to monitor them in living cells. Herein, we rationally designed and synthesized a dual-analytes responsive fluorescent sensor PTMQ for distinguishing detection of N2H4 and ClO−. PTMQ underwent N2H4-induced double bond cleavage, affording colorimetric and green fluorescence enhancement with good selectivity and a low detection limit (89 nM). On the other hand, PTMQ underwent ClO−-induced sulfur oxidation and displayed red fluorescence lighting-up response towards ClO− with good selectivity, rapid response (<0.2 min) and a low detection limit (58 nM). Moreover, PTMQ was successfully employed for in-situ imaging of N2H4 and ClO− in living cellsinfo:eu-repo/semantics/publishedVersio

Green polymers toward nanobiotechnology(I): synthesis of glycopolypeptides and their analogues

Harnessing natural-based renewable molecular resources to construct functional synthetic green polymers is a promising research frontier at the interface of sustainable/green chemistry, polymer chemistry and nanobiotechnology. As natural glycoprotein mimics/analogues and biocompatible building blocks of nanobio- materials, synthetic functional glycopolypeptides and their structural/functional analogues have attracted great attentions in recent years. This mini-perspective article reviewed current synthetic strategies and methods of glycopolypeptides and their analogues. The pros and cons of the synthesis protocols were discussed, moreover, possible future perspectives in this field were also stated.info:eu-repo/semantics/publishedVersio

A fast responsive chromogenic and near-infrared fluorescence lighting-up probe for visual detection of toxic thiophenol in environmental water and living cells

Thiophenols as high toxic environmental pollutants are poisonous for animals and aquatic organisms. Therefore, it is indispensable to monitor thiophenols in the environment. Herein, a novel near-infrared fluorescent probe was developed for the detection of thiophenols, which was easily prepared by one-step coupling of 2,4-dini trobenzenesulfonyl chloride with Nile blue. The probe showed a significant near infrared (∼675 nm) fluores cence “turn-on” response to thiophenols with some good features including chromogenic reaction, high sensi tivity and selectivity, fast response, near-infrared emission along with low detection limit (1.8 nM). The probe was employed to rapidly and visually determine thiophenols in several industrial wastewaters with good re coveries (90–110%). Moreover, this probe has been demonstrated good capability for imaging thiophenol in HeLa cellsinfo:eu-repo/semantics/publishedVersio

A selective cascade reaction-based probe for colorimetric and ratiometric fluorescence detection of benzoyl peroxide in food and living cells

A novel colorimetric and ratiometric fluorescent probe (Cou-BPO) was readily prepared for specific detection of harmful benzoyl peroxide (BPO). The probe Cou-BPO reacted with BPO via a selective oxidation cleavage-induced cascade reaction of the pinacol phenylboronate group, which resulted in an observable colorimetric and ratiometric fluorescence response towards BPO with a fast response time (o15 min) and a low detection limit (56 nM). For practical application, facile, portable and sensitive test paper of Cou-BPO has been prepared for visual detection of BPO. Furthermore, we employed Cou-BPO as a probe to determine BPO in food samples and living cells.info:eu-repo/semantics/publishedVersio

Polysaccharide-based nanomedicines for cancer immunotherapy: a review

Cancer immunotherapy is an effective antitumor approach through activating immune systems to eradicate tumors by immunotherapeutics. However, direct administration of “naked” immunotherapeutic agents (such as nucleic acids, cytokines, adjuvants or antigens without delivery vehicles) often results in: (1) an unsatisfactory efficacy due to suboptimal pharmacokinetics; (2) strong toxic and side effects due to low targeting (or off-target) efficiency. To overcome these shortcomings, a series of polysaccharide-based nanoparticles have been developed to carry immunotherapeutics to enhance antitumor immune responses with reduced toxicity and side effects. Polysaccharides are a family of natural polymers that hold unique physicochemical and biological properties, as they could interact with immune system to stimulate an enhanced immune response. Their structures offer versatility in synthesizing multifunctional nanocomposites, which could be chemically modified to achieve high stability and bioavailability for delivering therapeutics into tumor tissues. This review aims to highlight recent advances in polysaccharide-based nanomedicines for cancer immunotherapy and propose new perspectives on the use of polysaccharide-based immunotherapeutics.info:eu-repo/semantics/publishedVersio

Application of Zebrafish as a Model for Anti-Cancer Activity Evaluation and Toxicity Testing of Natural Products

Developing natural product-based anti-cancer drugs/agents is a promising way to overcome the serious side effects and toxicity of traditional chemotherapeutics for cancer treatment. However, rapid assessment of the in vivo anti-cancer activities of natural products is a challenge. Alternatively, zebrafish are useful model organisms and perform well in addressing this challenging issue. Nowadays, a growing number of studies have utilized zebrafish models to evaluate the in vivo activities of natural compounds. Herein, we reviewed the application of zebrafish models for evaluating the anti-cancer activity and toxicity of natural products over the past years, summarized its process and benefits, and provided future outlooks for the development of natural product-based anti-cancer drugs

Microfluidic-Based Cationic Cholesterol Lipid siRNA Delivery Nanosystem: Highly Efficient In Vitro Gene Silencing and the Intracellular Behavior

Safe and efficient delivery of small interfering RNA (siRNA) is essential to gene therapy towards intervention of genetic diseases. Herein, we developed a novel cationic cholesterol lipid derivative (CEL) in which cholesterol hydrophobic skeleton was connected to L-lysine cationic headgroup via a hexanediol linker as the non-viral siRNA delivery carrier. Well-organized CEL/siRNA nanocomplexes (100–200 nm) were prepared by microfluidic-assisted assembly of CEL and siRNA at various N/P ratios. The CEL and CEL/siRNA nanocomplexes have lower cytotoxicity compared with bPEI25k. Delightfully, we disclosed that, in Hela–Luc and H1299–Luc cell lines, the micro-fluidic-based CEL/siRNA nanocomplexes exhibited high siRNA transfection efficiency under both serum-free condition (74–98%) and low-serum circumstances (80–87%), higher than that of lipofectamine 2000. These nanocomplexes also showed high cellular uptake through the caveolae/lipid-raft mediated endocytosis pathway, which may greatly contribute to transfection efficiency. Moreover, the time-dependent (0–12 h) dynamic intracellular imaging demonstrated the efficient delivery to cytoplasm after lysosomal co-localization. The results indicated that the microfluidic-based CEL/siRNA nanosystems possessed good stability, low cytotoxicity, high siRNA delivery efficiency, rapid cellular uptake and caveolae/lipid raft-dependent internalization. Additionally, this study provides a simple approach for preparing and applying a “helper lipid-free” cationic lipid siRNA delivery system as potential nanotherapeutics towards gene silencing treatment of (tumor) diseases

Self‐assembly of cholesterol‐Doxorubicin and TPGS into Prodrug‐based nanoparticles with enhanced cellular uptake and Lysosome‐dependent pathway in breast cancer cells

Developing new easy-to-prepare functional drug delivery nanosystems with good storage stability, low hemotoxicity, as well as controllable drug delivery property, has attracted great attention in recent years. In this work, a cholesterol-based prodrug nanodelivery system is prepared by self-assembly of cholesterol-doxorubicin prodrug conjugates (Chol-Dox) and tocopherol polyethylene glycol succinate (TPGS) using thin-film hydration method. The Chol-Dox/TPGS assemblies (molar ratio 2:1, 1:1, and 1:2) are able to form nanoparticles with average hydrodynamic diameter of ≈140–214 nm, surface zeta potentials of ≈−24.2–−0.3 mV, and remarkable solution stability in 0.1 m PBS, 16 days). The Chol-Dox/TPGS assemblies show low hemotoxicity and different cytotoxicity profiles in breast cancer cells (MCF-7 and MDA-MB-231), which are largely dependent on the molar ratio of Chol-Dox and TPGS. The Chol-Dox/TPGS assemblies tend to enter into MCF-7 and MDA-MB-231 cells through non-Clathrin-mediated multiple endocytosis and lysosome-dependent uptake pathways, moreover, these nanoassemblies demonstrate lysosome-dependent intracellular localization, which is different from that of free DOX (nuclear localization). The results demonstrate that the Chol-Dox/TPGS assemblies are promising cholesterol-based prodrug nanomaterials for breast cancer chemotherapy. Practical Applications: This work demonstrates a lipid prodrug-based nanotherapeutic system. Herein the Chol-Dox/TPGS nanoassemblies could serve as promising and controllable cholesterol-based prodrug nanomaterials/nano-formulations for potential breast cancer chemotherapy.info:eu-repo/semantics/publishedVersio