Self-assembly of H2S-responsive nanoprodrugs based on natural rhein and geraniol for targeted therapy against Salmonella Typhimurium

Salmonellosis is a globally extensive food-borne disease, which threatens public health and results in huge economic losses in the world annually. The rising prevalence of antibiotic resistance in Salmonella poses a significant global concern, emphasizing an imperative to identify novel therapeutic agents or methodologies to effectively combat this predicament. In this study, self-assembly hydrogen sulfide (H2S)-responsive nanoprodrugs were fabricated with poly(α-lipoic acid)-polyethylene glycol grafted rhein and geraniol (PPRG), self-assembled into core-shell nanoparticles via electrostatic, hydrophilic and hydrophobic interactions, with hydrophilic exterior and hydrophobic interior. The rhein and geraniol are released from self-assembly nanoprodrugs PPRG in response to Salmonella infection, which is known to produce hydrogen sulfide (H2S). PPRG demonstrated stronger antibacterial activity against Salmonella compared with rhein or geraniol alone in vitro and in vivo. Additionally, PPRG was also able to suppress the inflammation and modulate gut microbiota homeostasis. In conclusion, the as-prepared self-assembly nanoprodrug sheds new light on the design of natural product active ingredients and provides new ideas for exploring targeted therapies for specific Enteropathogens. Graphical  illustration for construction of self-assembly nanoprodrugs PPRG and its antibacterial and anti-inflammatory activities on experimental Salmonella infection in mice.

Prolonged and Controllable Release of Doxorubicin Hydrochloride from the Composite Electrospun Poly(ε-Caprolactone)/Polyvinylpyrrolidone Scaffolds

Burst release, typical for the drug-loaded electrospun poly(ε-caprolactone) (PCL) scaffolds is unfavorable in case of cytostatics due to the toxic levels reached during the initial implantation period. In the present short communication, we report an unexpected ability of the composite scaffolds made of PCL and water-soluble polyvinylpyrrolidone (PVP) to provide long-term release of widely used anti-cancer drug doxorubicin hydrochloride (DOX-HCl). That effect was observed for electrospun DOX-HCl-loaded composite scaffolds based on PCL and PVP with various mass ratios (100/0, 95/5, 90/10, 75/25 and 50/50). After the morphology and water contact angle studies, it was concluded that PVP content has no effect on the average fiber diameter, while PVP content higher 10 wt. % changes the hydrophobic character of the scaffolds surface (water contact angle of 123.9 ± 3.5°) to superhydrophilic (water contact angle of 0°). Despite the dramatic change in water wettability, by high performance liquid chromatography (HPLC), it was revealed that the PVP content in the scaffolds reduces the DOX-HCl release rate under short (first hours) and long-term (during 1 month) exposure to phosphate buffer saline (PBS). These results are in good agreement with in vitro studies, in which the viability of HeLa cervical cancer cells was higher after 24 h of culture with scaffolds with high PVP content.

Synthesis approaches of amphiphilic copolymers for spherical micelle preparation: application in drug delivery

The formation of polymeric micelles in aqueous environments through the self-assembly of amphiphilic polymers can provide a versatile platform to increase the solubility and permeability of hydrophobic drugs and pave the way for their administration. In comparison to various self-assembly-based vehicles, polymeric micelles commonly have a smaller size, spherical morphology, and simpler scale up process. The use of polymer-based micelles for the encapsulation and carrying of therapeutics to the site of action triggered a line of research on the synthesis of various amphiphilic polymers in the past few decades. The extended knowledge on polymers includes biocompatible smart amphiphilic copolymers for the formation of micelles, therapeutics loading and response to external stimuli, micelles with a tunable drug release pattern, etc. Different strategies such as ring-opening polymerization, atom transfer radical polymerization, reversible addition-fragmentation chain-transfer, nitroxide mediated polymerization, and a combination of these methods were employed to synthesize copolymers with diverse compositions and topologies with the proficiency of self-assembly into well-defined micellar structures. The current review provides a summary of the important polymerization techniques and recent achievements in the field of drug delivery using micellar systems. This review proposes new visions for the design and synthesis of innovative potent amphiphilic polymers in order to benefit from their application in drug delivery fields.

Dextran-doxorubicin prodrug nanoparticles conjugated with CD147 monoclonal antibody for targeted drug delivery in hepatoma therapy

Antibody-drug conjugates (ADCs) are a class of tumor cell-targeting drugs that have developed rapidly in recent years. From the perspective of further improving ADC targeting and developing natural macromolecules as drug carriers, it is still challenging and necessary to try new targeted drug delivery modalities. In this study, we have developed an antibody-modified prodrug nanoparticle based on biomacromolecule dextran (DEX) to delivery antitumour drug doxorubicin (DOX). Firstly, oxidized dextran (ODEX) and DOX were bonded to yield ODEX-DOX via Schiff base reaction, which can self-assemble into nanoparticles (NPs) carrying some aldehyde groups. Subsequently, the amino groups of CD147 monoclonal antibody were bound to the aldehyde groups on the surface of ODEX-DOX NPs, resulting in acid-responsive and antibody-modified CD147-ODEX-DOX NPs with relatively small particle size and high DOX loading. FT-IR, UV-Vis, HPLC, and ¹H NMR were used to demonstrate the successful synthesis of polymer prodrug ODEX-DOX NPs and antibody-modified nanomedicine CD147-ODEX-DOX NPs. Dynamic light scattering (DLS) was used to evaluate the stability and the pH responsiveness of ODEX-DOX NPs in different media and tumour microenvironment. The in vitro total release content of DOX reached approximately 70% in PB 5.0 buffer solution after 103 h. Furthermore, the in vivo antitumour efficacy and biodistribution experiments confirmed that CD147-ODEX-DOX NPs could significantly inhibit the growth of HepG2 tumour. All of the results indicate that this acid-sensitive nanomedicine has higher safety and targeting effects. It promises to be an ideal strategy for future targeted drug delivery systems and anticancer therapies.

Construction of hyperbranched polysiloxane-based multifunctional fluorescent prodrug for preferential cellular uptake and dual-responsive drug release

Hyperbranched polymers hold great promise in nanomedicine for their controlled chemical structures, sizes, multiple terminal groups and enhanced stability than linear amphiphilic polymer assemblies. However, the rational design of hyperbranched polymer-based nanomedicine with low toxic materials, selective cellular uptake, controlled drug release, as well as real-time drug release tracking remains challenging. In this work, a hyperbranched multifunctional prodrug HBPSi-SS-HCPT is constructed basing on the nonconventional aggregation-induced emission (AIE) featured hyperbranched polysiloxanes (HBPSi). The HBPSi is a biocompatible AIE macromolecule devoid of conjugates, showing a high quantum yield of 17.88% and low cytotoxicity. By covalently grafting the anticancer drug, 10-hydroxycamptothecin (HCPT), to the HBPSi through 3,3'-dithiodipropionic acid, HBPSi-SS-HCPT is obtained. The HBPSis demonstrate obvious AIE features and it turned to aggregation-caused quenching (ACQ) after grafting HCPT owing to the FRET behavior between HBPSi and HCPT in HBPSi-SS-HCPT. In addition to on-demand HCPT release in response to changes in environmental pH and glutathione, a series of in vitro and in vivo studies revealed that HBPSi-SS-HCPT exhibits enhanced accumulation in tumor tissues through the enhanced permeation and retention (EPR) effect and preferential cancer cell uptake by charge reversal, thus resulting in apoptotic cell death subsequently. This newly developed multifunctional HBPSi-SS-HCPT prodrug provides a biocompatible strategy for controlled drug delivery, preferential cancer cell uptake, on-demand drug release and enhanced antitumor efficacy.

Supramolecular Polymeric Prodrug Micelles for Efficient Anticancer Drug Delivery

Polymeric prodrugs have attracted great interest in the field of antitumor drug delivery owing to its integrated advantages of prodrugs and nanoparticles. However, the ambiguous chemical composition of polymeric prodrugs...

Recent applications of electrical, centrifugal, and pressurised emerging technologies for fibrous structure engineering in drug delivery, regenerative medicine and theranostics

Advancements in technology and material development in recent years has led to significant breakthroughs in the remit of fiber engineering. Conventional methods such as wet spinning, melt spinning, phase separation and template synthesis have been reported to develop fibrous structures for an array of applications. However, these methods have limitations with respect to processing conditions (e.g. high processing temperatures, shear stresses) and production (e.g. non-continuous fibers). The materials that can be processed using these methods are also limited, deterring their use in practical applications. Producing fibrous structures on a nanometer scale, in sync with the advancements in nanotechnology is another challenge met by these conventional methods. In this review we aim to present a brief overview of conventional methods of fiber fabrication and focus on the emerging fiber engineering techniques namely electrospinning, centrifugal spinning and pressurised gyration. This review will discuss the fundamental principles and factors governing each fabrication method and converge on the applications of the resulting spun fibers; specifically, in the drug delivery remit and in regenerative medicine.

Zwitterionic Nanogels and Microgels: An Overview on Their Synthesis and Applications

Zwitterionic polymers by virtue of their unique chemical and physical attributes have attracted researchers in recent years. The simultaneous presence of positive and negative charges in the same repeat unit renders them of various interesting properties such as superhydrophilicity, which has significantly broadened their scope for being used in different applications. Among polyzwitterions of different architectures, micro- and/or nano-gels have started receiving attention only until recently. These 3D cross-linked colloidal structures show peculiar characteristics in context to their solution properties, which are attributable either to the comonomers present or the presence of different electrolytes and biological specimens. In this review, a concise yet detailed account is provided of the different synthetic techniques and application domains of zwitterion-based micro- and/or nanogels that have been explored in recent years. Here, the focus is kept solely on the "polybetaines," which have garnered maximum research interest and remain the extensively studied polyzwitterions in literature. While their vast application potential in the biomedical sector is being detailed here, some other areas of scope such as using them as microreactors for the synthesis of metal nanoparticles or making smart membranes for water-treatment are discussed in this minireview as well.

CD147 Monoclonal Antibody Targeted Reduction-Responsive Camptothecin Polyphosphoester Nanomedicine for Drug Delivery in Hepatocellular Carcinoma Cells

In the treatment of tumor-targeted small-molecule anti-cancer drugs, antibody-mediated therapies, especially for antibody-drug conjugates (ADCs), have revealed great latent force. However, the therapeutic drugs provided by ADCs possess limitation. Considering that the combination of antibodies and nano-drugs can broaden their applicability in the field of tumor treatment, herein, we developed an antibody conjugated polymeric prodrug nanoparticles SAE-PEG-b-PBYP-ss-CPT for targeted camptothecin (CPT) delivery to liver tumor cells. The diblock copolymer was composed of PEG and biodegradable polyphosphoester (PBYP) containing alkynyl groups in the side chain. A derivative of CPT (CPT-ss-N₃) was bonded to the PBYP via "click" reaction. The diethyl squarate (SAE) in the terminal of PEG chain was used as a functional group to bond with CD147 monoclonal antibody (CD147 mAb). The particle size and size distribution of the both nanoparticles, with antibody binding (namely CD147-CPT NPs) and without antibody (abbreviated as CPT-loaded NPs), were measured by dynamic light scattering (DLS). The morphologies of both two kinds of nanoparticles were observed by transmission electron microscope (TEM). The results of X-ray photoelectron spectroscopy (XPS) showed that CD147 mAb had been coupled to the surface of CPT-loaded NPs. Endocytosis test indicated that CD147-CPT NPs had higher uptake rate and accumulation in HepG2 cells than those of CPT-loaded NPs without antibodies, due to CD147 mAb can specifically bind to CD147 protein overexpressed in HepG2 cells. We establish a method to bond monoclonal antibodies to anti-cancer polymeric prodrugs, and endow biodegradable polymeric prodrugs with precise targeting functions to liver cancer cells.

Reduction-Responsive Anticancer Nanodrug Using a Full Poly(ethylene glycol) Carrier

Poly(ethylene glycol) (PEG) is applied extensively in biomedical fields because of its nontoxic, nonimmunogenic, and protein resistance properties. However, the strong hydrophilicity of PEG prevents it from self-assembling into an amphiphilic micelle in water, making it a challenge to fabricate a full-PEG carrier to deliver hydrophobic anticancer drugs. Herein, a paclitaxel (PTX)-loaded nanodrug was readily prepared through self-assembly of PTX and an amphiphilic PEG derivative, which was synthesized via melt polycondensation of two PEG diols (i.e., PEG₂₀₀ and PEG_10k) and mercaptosuccinic acid. The full PEG component endows the nanocarrier with good biocompatibility. Furthermore, because of the core cross-linked structure via the oxidation of mercapto groups, the nanodrug can be selectively disassociated under an intratumor reductive microenvironment through the reduction of disulfide bonds to release the loaded PTX and kill the cancer cells while maintaining high stability under the extratumor physiological condition. Additionally, it was confirmed that the nanodrug not only prolongs the biocirculation time of PTX but also possesses excellent in vivo antitumor efficacy while avoiding side effects of free PTX, for example, liver damage, which is promising for delivering clinical hydrophobic drugs to treat a variety of malignant tumors.

Blood circulation stable doxorubicin prodrug nanoparticles containing hydrazone and thioketal moieties for antitumor chemotherapy

Prodrug nanoparticles with cleavable moieties sensitive to intracellular stimuli have drawn great attention on cancer chemotherapy. Herein, a reactive oxygen species (ROS)-responsive doxorubicin prodrug mPEG-Phe-TK-Phe-hyd-DOX was synthesized, in which hydrophilic methoxy poly(ethylene glycol) (mPEG) and hydrophobic anticancer drug doxorubicin (DOX) were conjugated with hydrazone (hyd) and ROS-responsive thioketal (TK) moieties. The ROS-responsiveness of prodrug was confirmed by proton nuclear magnetic resonance (¹H NMR) and dynamic light scattering (DLS). Unexpectedly, the results of in vitro drug release indicated that the hydrazone bond of prodrug nanoparticles was insensitive to pH, which may be due to the strong hydrophobicity, π-π interactions and cation-π interactions jointly inhibited the hydrolysis of hydrazone bonds under acidic conditions. The cellular uptake and in vitro anticancer study showed that ROS-responsive prodrug nanoparticles exhibited faster cellular uptake and better anticancer efficacy. The in vivo experiments showed that the ROS-responsive prodrug nanoparticles had comparable antitumor efficacy with free anticancer drug DOX and reduced organ toxicity. Our results provide novel idea of successfully design multi-stimuli-responsive nano-drug carrier.

A biodegradable CO2-based polymeric antitumor nanodrug via a one-pot surfactant- and solvent-free miniemulsion preparation

In the present study, low molecular weight poly(propylene carbonate) (PPC, Mn = 3500), a biodegradable liquid polymer easily prepared from carbon dioxide (CO2), was modified into poly(propylene carbonate)diacrylate (PPC-DA) by acylation, and methoxy poly(ethylene glycol) (mPEG) was modified into methoxy poly(ethylene glycol) acrylate (mPEG-A). Using PPC-DA as the dispersant to dissolve hydrophobic doxorubicin (DOX) and the initiator, and with mPEG-A as the co-monomer and polymerisable surfactant, a biodegradable nanodrug with excellent biocompatibility was prepared by shear emulsification polymerization without surfactants or organic solvent residues. The nanodrug can be efficiently endocytosed by tumor cells and can rapidly release doxorubicin triggered by the acidic endosomal pH. As evidenced by experiments in tumor-bearing mice, such a nanodrug is stealthy during blood circulation, and targets tumor sites with high efficiency. Moreover, this nanodrug is more effective and less toxic than free doxorubicin. This study provides a green and versatile approach for preparing biodegradable nanodrugs via a simple and efficient process. Moreover, this study extends the applications of CO2 based polymers in the biomedical field, promoting the development of CO2 polymerization fixation.

Multifunctional Polymeric Prodrug with Simultaneous Conjugating Camptothecin and Doxorubicin for pH/Reduction Dual-Responsive Drug Delivery

Amphiphilic polymeric prodrugs show improved therapeutic indices with respect to traditional hydrophobic anticancer drugs because these prodrugs can self-assemble into nanoparticles, prolong the circulation of drugs in the blood, improve the accumulation of drugs in the disease site, reduce the side effects of drugs, and achieve therapeutic effect. Here, we describe a novel pH/reduction dual-responsive polymeric prodrug, abbreviated as CPT- ss-poly(BYP_{- hyd-DOX}- co-EEP), with simultaneous conjugating camptothecin (CPT) and doxorubicin (DOX), wherein BYP and EEP represent two cyclic phosphate monomers, respectively, that is, 2-(but-3-yn-1-yloxy)-2-oxo-1,3,2-dioxaphospholane and 2-ethoxy-2-oxo-1,3,2-dioxaphospholane. This prodrug was prepared through a polyphosphoester-DOX conjugate using a CPT derivative (CPT- ss-OH) as the initiator. CPT is linked to the terminal of polyphosphoester via disulfide carbonate, which is easy to break up under intracellular reductive environment and release the parent CPT, whereas DOX was efficiently incorporated onto the pendants of polyphosphoester through a hydrazone bond (- hyd-), which would be cleaved in the intracellular acidic medium. We show that the stable prodrug nanoparticles formed by self-assembly could release CPT and DOX simultaneously in the tumor microenvironment. The results of MTT assay demonstrate that the prodrug, which binds two antitumor drugs simultaneouly, has the properties of dual pH/reduction sensitiveness, biocompatibility, biodegradability, and effective tumor therapy.

Zwitterionic shielded polymeric prodrug with folate-targeting and pH responsiveness for drug delivery

Zwitterionic polymers are a class of polymers that acts as both Lewis base and Lewis acid in solution. These polymers not only have excellent properties of hydration, anti-bacterial adhesion, charge reversal and easy chemical modification, but also have characteristics of long-term circulation and suppress nonspecific protein adsorption in vivo. Here, we describe a novel folate-targeted and acid-labile polymeric prodrug under the microenvironment of tumor cells, abbreviated as FA-P(MPC-co-PEGMA-BZ)-g-DOX, which was synthesized via a combination of reversible addition-fragmentation chain transfer (RAFT) copolymerization, Schiff-base reaction, Click chemistry, and a reaction between the amine group of doxorubicin (DOX) and aldehyde functionalities of P(MPC-co-PEGMA-BZ) pendants, wherein MPC and PEGMA-BZ represent 2-(methacryloyloxy)ethyl phosphorylcholine and polyethylene glycol methacrylate ester benzaldehyde, respectively. The polymeric prodrug could self-assemble into nanoparticles in an aqueous solution. The average particle size and morphologies of the prodrug nanoparticles were observed by dynamic light scattering (DLS) and transmission electron microscopy (TEM), respectively. We also investigated the in vitro drug release behavior and observed rapid prodrug nanoparticle dissociation and drug release under a mildly acidic microenvironment. The methyl thiazolyl tetrazolium (MTT) assay verified that the P(MPC-co-PEGMA-BZ) copolymer possessed good biocompatibility and the FA-P(MPC-co-PEGMA-BZ)-g-DOX prodrug nanoparticles showed higher cellular uptake than those prodrug nanoparticles without the FA moiety. The results of cytotoxicity and the intracellular uptake of non-folate/folate targeted prodrug nanoparticles further confirmed that FA-P(MPC-co-PEGMA-BZ)-g-DOX could be efficiently accumulated and rapidly internalized by HeLa cells due to the strong interaction between multivalent phosphorylcholine (PC) groups and cell membranes. This kind of multifunctional FA-P(MPC-co-PEGMA-BZ)-g-DOX prodrug nanoparticle with combined target-ability and pH responsiveness demonstrates promising potential for cancer chemotherapy.

One-Pot Synthesis of pH/Redox Responsive Polymeric Prodrug and Fabrication of Shell Cross-Linked Prodrug Micelles for Antitumor Drug Transportation

Shell cross-linked (SCL) polymeric prodrug micelles have the advantages of good blood circulation stability and high drug content. Herein, we report on a new kind of pH/redox responsive dynamic covalent SCL micelle, which was fabricated by self-assembly of a multifunctional polymeric prodrug. At first, a macroinitiator PBYP- ss- iBuBr was prepared via ring-opening polymerization (ROP), wherein PBYP represents poly[2-(but-3-yn-1-yloxy)-2-oxo-1,3,2-dioxaphospholane]. Subsequently, PBYP- hyd-DOX- ss-P(DMAEMA- co-FBEMA) prodrug was synthesized by a one-pot method with a combination of atom transfer radical polymerization (ATRP) and a Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction using a doxorubicin (DOX) derivative containing an azide group to react with the alkynyl group of the side chain in the PBYP block, while DMAEMA and FBEMA are the abbriviations of N, N-(2-dimethylamino)ethyl methacrylate and 2-(4-formylbenzoyloxy)ethyl methacrylate, respectively. The chemical structures of the polymer precursors and the prodrugs have been fully characterized. The SCL prodrug micelles were obtained by self-assembly of the prodrug and adding cross-linker dithiol bis(propanoic dihydrazide) (DTP). Compared with the shell un-cross-linked prodrug micelles, the SCL prodrug micelles can enhance the stability and prevent the drug from leaking in the body during blood circulation. The average size and morphology of the SCL prodrug micelles were measured by dynamic light scattering (DLS) and transmission electron microscopy (TEM), respectively. The SCL micelles can be dissociated under a moderately acidic and/or reductive microenvironment, that is, endosomal/lysosomal pH medium or high GSH level in the tumorous cytosol. The results of DOX release also confirmed that the SCL prodrug micelles possessed pH/reduction responsive properties. Cytotoxicity and cellular uptake analyses further revealed that the SCL prodrug micelles could be rapidly internalized into tumor cells through endocytosis and efficiently release DOX into the HeLa and HepG2 cells, which could efficiently inhibit the cell proliferation. This study provides a fast and precise synthesis method for preparing multifunctional polymer prodrugs, which hold great potential for optimal antitumor therapy.

A reactive oxygen species–responsive prodrug micelle with efficient cellular uptake and excellent bioavailability

Stimuli-responsive polymeric drug delivery systems are of great interest in anticancer research. Here, a reactive oxygen species (ROS)–responsive prodrug was prepared by thioketal linkage of poly(ethylene glycol) (PEG) and the anticancer drug doxorubicin (DOX).

Polyphosphoester-Camptothecin Prodrug with Reduction-Response Prepared via Michael Addition Polymerization and Click Reaction

Polyphosphoesters (PPEs), as potential candidates for biocompatible and biodegradable polymers, play an important role in material science. Various synthetic methods have been employed in the preparation of PPEs such as polycondensation, polyaddition, ring-opening polymerization, and olefin metathesis polymerization. In this study, a series of linear PPEs has been prepared via one-step Michael addition polymerization. Subsequently, camptothecin (CPT) derivatives containing disulfide bonds and azido groups were linked onto the side chain of the PPE through Cu(I)-catalyzed azidealkyne cyclo-addition "click" chemistry to yield a reduction-responsive polymeric prodrug P(EAEP-PPA)-g-ss-CPT. The chemical structures were characterized by nuclear magnetic resonance spectroscopy, gel permeation chromatography, Fourier transform infrared, ultraviolet-visible spectrophotometer, and high performance liquid chromatograph analyses, respectively. The amphiphilic prodrug could self-assemble into micelles in aqueous solution. The average particle size and morphology of the prodrug micelles were measured by dynamic light scattering and transmission electron microscopy, respectively. The results of size change under different conditions indicate that the micelles possess a favorable stability in physiological conditions and can be degraded in reductive medium. Moreover, the studies of in vitro drug release behavior confirm the reduction-responsive degradation of the prodrug micelles. A methyl thiazolyl tetrazolium assay verifies the good biocompatibility of P(EAEP-PPA) not only for normal cells, but also for tumor cells. The results of cytotoxicity and the intracellular uptake about prodrug micelles further demonstrate that the prodrug micelles can efficiently release CPT into 4T1 or HepG2 cells to inhibit the cell proliferation. All these results show that the polyphosphoester-based prodrug can be used for triggered drug delivery system in cancer treatment.

Stimuli-responsive polymers and their applications

Responsive polymer-based materials are capable of altering their chemical and/or physical properties upon exposure to external stimuli. This review highlights their use for sensing and biosensing, drug delivery, and artificial muscles/actuators.

Dual-responsive core-crosslinked polyphosphoester-based nanoparticles for pH/redox-triggered anticancer drug delivery

The paper focuses on the preparation of biodegradable pH/redox dual-responsive core-crosslinked nanoparticles loaded with dual anticancer drugs PTX and DOX via synergetic electrostatic as well as hydrophobic interactions and their further application in tumor chemotherapy.

New Insight into a Cancer Theranostic Probe: Efficient Cell-Specific Delivery of SN-38 Guided by Biotinylated Poly(vinyl alcohol)

An optically modulated "turn-on" theranostic prodrug TP1 has been explored and formulated with biotinylated poly(vinyl alcohol) (biotinPVA) to obtain desired pharmacokinetics. TP1, consisting of the antineoplastic camptothecin analogue SN-38, and the fluorescent dye rhodol green have been covalently conjugated through a disulfide bond. Glutathione triggering the release of drug and fluorophore has been well established by UV-vis measurements through mass spectral analysis in physiological conditions. The biocompatible biotinPVA formulated prodrug (PTP1) showed remarkably higher stability against blood serum and cell-specific activation in contrast to that of TP1. Significantly, PTP1 permits monitoring of the delivery and release of well-known topoisomerase I inhibitor SN-38 by modulating fluorescence signal at λ_em 550 nm within intracellular milieus. Moreover, theranostic probe PTP1 exhibited dose-dependent antiproliferative activity against receptor-positive HeLa cells, whereas it did not show such an effect against receptor-negative NIH3T3 cells. Finally, the cell-specific antiproliferative activity of PTP1 via the apoptotic pathway is an efficient approach in cancer theranostics. Thus, futuristic PTP1 could be a promising agent in which diagnostic and prognostic data will be monitored synergistically.

Injectable camptothecin conjugated hydrogels with simultaneous drug release and degradation

Novel injectable camptothecin conjugated hydrogels with simultaneous drug release and degradation properties were prepared, which show significant cytotoxicity to HepG2 cells, and could be a potential candidate for intratumor drug delivery.

Redox-responsive, core-crosslinked degradable micelles for controlled drug release

We developed novel redox-responsive, core-crosslinked micelles (CCLMs) via a simple, one-step click chemistry reaction.

A co-delivery system based on a reduction-sensitive polymeric prodrug capable of loading hydrophilic and hydrophobic drugs for combination chemotherapy

A reduction-sensitive polymeric prodrug PEG-b-PMPMC-g-PTX was designed. The self-assemblies of polymeric prodrug could deliver drugs with different action mechanisms into tumor cells, leading to the apoptosis of tumor cells effectively.