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A robust approach that centers on carbonyl imidazole chemistry was used to synthesize a triple-stimuli-responsive degradable block copolymer labeled with acetal, disulfide, and o-nitrobenzyl groups exhibiting acid, reduction, and light responses.

Exploration of effective approaches that allow for the synthesis of smart block copolymers and their nanoassemblies exhibiting enhanced drug release upon stimuli-responsive degradation is in huge d...

The impact of styrene–butadiene–styrene (SBS) and maleated styrene–ethylene–butylene–styrene (SEBS-g-MA) weight ratios was studied on the microstructure and ultimate performance of PP/PBT/(SBS + SEBS-g-MA) (70/15/15) blends. Morphological observations revealed a gradual change in the dispersions state of modifier domains from isolated phases to stack formation and then to encapsulation morphology as the SEBS-g-MA proportion was steadily increased. This was accompanied by improved blend homogeneity and finer dispersion of PBT domains (a drop in particle size from ~ 3 μm to ~ 0.3 μm) with increase of SEBS-g-MA concentration in the rubbery fraction of the blend. The alteration of morphology was manifested in macroscopic mechanical properties of the blends. Young’s modulus declined (~ 20%) whereas yield stress (~ 17%), tensile strength (~ 16%), and tensile ductility (~ 210%) were steadily enhanced with increase of SEBS-g-MA concentration in the rubbery fraction of the blend. The notched Izod impact strength also monotonically rose (~ 150%) as SBS:SEBS-g-MA weight ratio was reduced. The improvement of mechanical properties of the blends was attributed to improved blend compatibility and interfacial adhesion followed by more homogeneous mixing state between blend components upon progressive replacement of SBS component with SEBS-g-MA phase. The crystalline- and phase structure of the blends were studied by DCS and DMTA analyses, respectively and correlated with the blend composition and morphology. The impact-fractured surface of the toughened blends was examined and the deformation mechanisms were clarified. Increased resistance against particle debonding along with the development of microvoids induced by rubber phase was responsible for the enhanced impact fracture energy of these blends.

The effects of processing conditions were studied on the phase morphology and mechanical properties of the polypropylene/polybutylene terephthalate (PP/PBT) blends toughened by styrene-butadiene triblock copolymer thermoplastic elastomers. Highly toughened PP-based blends that exhibited increased impact strength (seven- to ninefold) and little loss of stiffness (

Polycystic ovary syndrome (PCOS) is one of the most prevalent polygenic endocrine disorders in reproductive-age women. Genistein is a soy-isolated phytoestrogen and isoflavone with antioxidant, anti-inflammatory, estrogenic, and antineoplastic activity. This systematic review aimed to investigate the therapeutic effects and mechanisms of actions of genistein in PCOS. The present study was conducted according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. We searched PubMed, Scopus, Embase, and Google Scholar databases up to February 2022 using relative keywords. Studies published in English evaluated genistein's effects on PCOS, and its related symptoms were considered. Out of 298 records screened, only 13 articles met the inclusion criteria: Nine animal and 4 human studies. The results of the current study indicated that genistein supplementation may effectively improve PCOS-related symptoms by decreasing insulin resistance and anthropometric indices, improving ovarian morphology and regulating reproductive hormones, and reducing oxidative stress and inflammation by influencing biological pathways. According to the current literature, genistein may diminish the dues of PCOS. Therefore, this study shows that genistein can be considered an effective agent. in reducing the complications of PCOS. However, further studies are recommended for a broad conclusion on the exact mechanism of genistein in PCOS patients.

Chronic pruritus is one of the most common conditions in dermatology and a common manifestation in many systemic diseases. Since the etiology of chronic pruritus remains somewhat unknown, hence, conventional medications may not always show a good therapeutic response. This finding has led both investigators and patients to use herbal and complementary remedies for its treatment. The aim of this study was to review clinical trials in which herbal and complementary medicine was used in the control and treatment of chronic pruritus.In this study, we reviewed related articles in this domain, from 2000 to 2020. The search involved electronic databases including PubMed, Scopus, Web of Science, Cochrane, Google Scholar, and SID databases using the keywords "pruritus," "itch," "herb," "complementary medicine," "traditional medicine," "integrative medicine," and their related MeSH terms. Finally, we extracted the pertinent information from these articles and summarized the results.The findings of this study showed that 17 clinical trials have been conducted till date in order to evaluate the efficacy of herbal remedies and complementary medicines in the treatment of chronic pruritus. Herbal remedies including turmeric, Fumaria parviflora, Avena sativa, capsaicin, sweet almond oil, peppermint oil, violet oil, vinegar, as well as manual therapies including aromatherapy, auricular acupressure, and acupuncture, were significantly effective in the treatment of chronic pruritus.There are only a few studies published on the therapeutic efficacy of herbal remedies and complementary medicine in the treatment of chronic pruritus. Some have shown promising results. Therefore, more evidence-based studies are needed in order to determine if herbal remedies and complementary medicine could be an effective alternative or adjuvant treatment modality in chronic pruritus.

Nitric oxide (NO) plays a critical role as an important signaling molecule for a variety of biological functions, particularly inhibiting cell proliferation or killing target pathogens. To deliver active radical NO gaseous molecule whose half-life is a few seconds in a stable state, the design and development of effective exogenous NO supply nanocarriers are essential. Additionally, the delivery of desired drugs with NO can produce synergistic effects. Herein, we report a new approach that allows for the fabrication of dual ultrasound (US)/glutathione (GSH)-responsive perfluorocarbon (PFC) nanodroplets for the controlled release of model drug and passive release of safely incorporated NO. The approach centers on the synthesis of a disulfide-labeled amphiphilic block copolymer and its use as a GSH-degradable macromolecular emulsifier for oil-in-water emulsification process of PFC. The fabricated PFC nanodroplets are colloidally stable and enable the encapsulation of both NO and model drugs. Encapsulated drug molecules are synergistically released when ultrasound and GSH are presented, while NO molecules are passively but rapidly released. Our preliminary results demonstrate that the approach is versatile and can be extended to not only GSH-responsive but also other stimuli-responsive block copolymers, thereby allowing for the fabrication of broad choices of stimuli-responsive (smart) PFC-nanodroplets in aqueous solution for dual delivery of drug and NO therapeutics.

We demonstrate microfluidic manufacturing of glutathione (GSH)-responsive polymer nanoparticles (PNPs) with controlled

Drug delivery via block copolymer nanoassemblies has been widely viewed as an efficient way to augment therapeutic efficiency of anticancer drugs for cancer therapy. Acid-degradable block copolymer-based nanoassemblies are promising intracellular candidates for tumor-targeting drug delivery as they exhibit enhanced release of encapsulated drugs through their dissociation (or disintegration) upon cleavage of acid-labile linkages in response to a tumor's acidic environment (pH = 4.2–6.7). Furthermore, degradation of the self-assemblies via acid-catalyzed hydrolysis can be tuned with a choice of various available acid-labile linkages. This review summarizes recent advances in the synthesis and disassembly of acid-cleavable block copolymers for controlled drug delivery. Strategies to integrate acid-labile covalent linkages in block copolymers at different locations, as in micelle cores and core/corona interfaces are particularly focused upon. Additionally, elegant strategies that allow for the synthesis of dual acid/reduction, acid/light, acid/enzyme-degradable block copolymer systems with cleavable linkages in single or dual locations are discussed.

Atopic dermatitis (AD) and psoriasis are chronic inflammatory diseases that have significant skin complications.The purpose of this systematic study was to evaluate the evidence obtained from human studies on the effects of hydrotherapy, spa therapy, and balneotherapy in psoriasis and atopic dermatitis.The present systematic review was conducted according to the guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statements. Also, for this study databases such as Embase, PubMed, Scopus ProQuest, and sciences direct database were searched from the beginning to April 2021.All human studies that examined the effect of balneotherapy, spa therapy, and hydrotherapy on psoriasis and atopic dermatitis were published in the form of a full article in English. In the end, only 22 of the 424 articles met the criteria for analysis. Most studies have shown that balneotherapy, spa therapy, and hydrotherapy may reduce the effects of the disease by reducing inflammation and improving living conditions. In addition, the results of the Downs and Black score show that seven studies received very good scores, three studies received good scores, nine studies received fair scores, and three studies received poor scores.The results of studies also showed that hydrotherapy leads to an improvement in the PASI score index. Nevertheless, more clinical trials are needed to determine the mechanism of action of hydrotherapy on these diseases.

Background Cichorium intybus is a rich source of terpenoids and phenolic compounds, one of the effective methods in managing and reducing the complications of chronic diseases such as diabetes mellitus. The purpose of this systematic review was to evaluate the evidence obtained from animal and human studies on the effects of chicory on metabolic indicators (such as inflammation, oxidative stress, blood sugar and dyslipidaemia) of diabetes mellitus. Materials and methods This systematic search was performed in ProQuest, PubMed, Google Scholar, Scopus, Cochrane Central Register of Controlled Trials, Embase and Science Direct databases and on articles published until August 2021. All of the animal studies and clinical trials included in this systematic review that assessed the effect of chicory on metabolic risk markers in diabetes were published in English language journals. Results Finally, amongst 686 articles, only 23 articles met the needed criteria for further analysis. Out of 23 articles, 3 studies on humans and 20 studies on animals have been carried out. Fifteen of the 19 studies that evaluated the effect of chicory on the glycaemic index showed that Cichorium intybus improved blood glucose index (it had no effect in two human studies and three animal studies). Ten of the 13 studies evaluating the effect of Cichorium intybus on lipid profiles showed that it improved dyslipidaemia. Also, all 12 studies showed that chicory significantly reduces oxidative stress and inflammation. Conclusion According to the available evidence, Cichorium intybus might improve the glycaemic status, dyslipidaemia, oxidative stress and inflammation. However, further studies are recommended for a comprehensive conclusion about the exact mechanism of chicory in diabetic patients.

Atom transfer radical polymerization (ATRP) of oligo(ethylene oxide) monomethyl ether methacrylate (OEOMA

and amis: Diabetes is one of the major medical problems, which can lead to damage to cells or organs in various parts of the body. Saffron as herbal medicine has contained several active ingredients, including safranal, flavonoids, crocetin, and crocin, which are effective in modulating oxidative stress and inflammation, which can play the main role in reducing the effects of diabetes. However, so far, the effect of saffron on diabetes inflammation has not been evaluated in the form of systematic review studies. The purpose of this systematic study was to evaluate the evidence obtained from in-vitro, animal, and clinical trials studies on the effects of saffron on inflammation in diabetes.The present systematic review was conducted according to the guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statements. In this systematic review, databases such as Embase, Pubmed, SCOPUS, ProQuest, and sciences direct database were searched from the beginning to February 2021. All eligible in-vitro, animal and human studies that examined the effect of saffron on inflammatory factors in diabetes were published in the form of a full article in English.In the end, only 20 of the 596 articles met the criteria for analysis. Of the 20 articles, 3 were in-vitro studies, 13 were animal studies, and 4 were human studies.The findings of this systematic study (Except for two studies) suggest that saffron supplementation with potential anti-inflammatory properties may reduce the expression of the inflammatory pathway and the production of inflammatory products in diabetes.

BACKGROUND: Polycystic ovary syndrome (PCOS) is a frequent medical condition characterized by both metabolic and reproductive disorders. Different pharmaceutical treatments have been proposed for PCOS. However, side effects of long-term treatments and their probable low efficacy have made complementary and alternative treatments a valuable option. Recent reports have indicated the increased use of complementary treatments. Herbal medicine, as part of complementary medicine, was find introduced in traditional Persian and Chinese medicine. Medicinal herbs have used for a long time in the treatment of gynecological and infertility problems of PCOS patients. In this study, we aimed to review herbal medicines used for PCOS worldwide. METHODS: PubMed, Embase, Cochrane, and Scopus databases were searched for clinical trials and Randomized Controlled Trials based on related keywords. Data were collected from 1990 to 2019. RESULTS: According to a multitude of studies, a wide spectrum of herbs can be used to improve various aspects of PCOS. Herbs such as Cinnamomum verum, Trigonella foenum-graecum L., and Vitex agnus-castus can impact on menstrual and ovulatory dysfunctions, obesity, insulin resistance, lipid-metabolism dysfunction, and androgen excess-related conditions. CONCLUSION: Some plants as natural remedies may have beneficial effects on improving different aspects of PCOS; but further studies are needed to investigate their mechanisms and safety.

Epoxy adhesives are prone to brittle failure and thermal degradation. Nanotechnology allows for developing advanced epoxy adhesives, but attempt to design high-performance epoxy adhesives must be made by starting inexpensive trials in micron scales by the use of recycled and waste materials. Phenolic resin, recycled tire powder, and alumina microfillers were systematically mixed here as epoxy toughening agent and modulus/strength modifier, respectively. Incorporation of phenolic resin to epoxy compensated for low thermal stability. Taguchi experimental design was used to study the main effects of waste tire powder, alumina microparticles, and phenolic resin contents on tensile, single-lap joint and thermogravimetric properties of epoxy adhesive. The results suggest that addition of 40 wt. % alumina microparticles, 15 wt. % recycled tire powder, and 30 wt. % phenolic resin to epoxy led to a drastic rise of ca. 80% in the lap shear strength with respect to the neat epoxy. Microscopic analyses unraveled blocking mechanism for cracking, as evidenced by a deviation in crack growth pathway at the vicinity of alumina microparticles. A considerable increase of ca. 34 °C in degradation peak temperature of epoxy was also noticeable. The outcome of this work enlightened future perspective on nanostructured epoxy adhesives.

Silicone elastomer coatings are known for their softness and high elongation properties, but not for faithful service over time because of their inadequate adhesion, thermal, and mechanical properties. Addition of nanofillers to silicone would be the solution to such long-standing shortcomings, but yet there is a little guarantee of success because of silicone crosslinking being significantly hindered by filler incorporation. In this work, well-cured 3D silicone networks are formed by peroxide curing in the presence of pristine and silane-functionalized halloysite nanotubes (HNTs). Nanofillers are incorporated into silicone at different loadings and the curing potential of the resulting nanocomposite coatings are evaluated by dimensionless indexes of T* and ΔH* calculated from nonisothermal differential scanning calorimetry. Regardless of the content and surface chemistry of the HNTs, silicone nanocomposite was outstandingly cured by peroxide thanks to reactive surface of nanofillers. Overall, ΔH* value of ≈ 2 was indicative of a two-fold rise in the amount of heat release in silicone nanocomposites whatever heating rate. Moreover, T* values obtained were slightly lower than 1, a signature of an unhindered curing. The excellence of facilitated crosslinking brought about by the use of HNTs was featured by an improved polymer-filler interaction, which seems promising for coating applications.

Smart nanoassemblies based on well-controlled block copolymers degradable in response to dual endogenous stimuli, particularly acidic pH and glutathione (reduction) found in tumor tissues and cancer cells, are promising candidates as tumor-targeting drug delivery nanocarriers. Here, we report an approach to develop dual acid/reduction-degradable block copolymer nanoassemblies having acid-cleavable ketal linkages at core/corona interfaces and disulfide pendants in micellar cores, thus attaining dual stimuli responses at dual locations. The approach employing reversible addition–fragmentation chain transfer (RAFT) polymerization with a newly synthesized poly(ethylene glycol)-based macro-RAFT agent labeled with a ketal linkage (PEG-ketal-RAFT, P4) allows for the synthesis of a well-controlled block copolymer (P5) composed of a hydrophilic PEG block connected through a ketal linkage with a hydrophobic methacrylate block having pendant disulfide linkages. The amphiphilic nature of P5 ensures the fabrication of nanoassemblies loaded with doxorubicin (a clinically used anticancer drug) through aqueous micellization. Not only the cleavage of the ketal linkages in endosomal or lysosomal pH sheds coronas at interfaces, but also the reductive cleavage of pendant disulfides to the corresponding thiols in the presence of cellular glutathione causes a change in the hydrophobic/hydrophilic balance in micelle cores. These dual acid/reduction responses that occurred at dual locations lead to the synergistic and accelerated drug release, compared with single response at single location. These results, combined with in vitro cell culture experiments including cell viability and cellular uptake, demonstrate the versatility of dual location dual acidic pH/reduction-responsive degradation in the development of tumor-targeting intracellular drug delivery vehicles for cancer chemotherapy.

Epoxy resins can be cured with a wide variety of curing agents such as amines and anhydrides, but anhydride curing would be more favorable for research purpose because of epoxy-anhydride curing taking place slowly at room temperature. Incorporation of natural nanosized minerals into epoxy is of environmental importance. Halloysite nanotubes (HNTs) display chemical properties similar to those of silica and alumina, and hydroxyl groups positioned somewhere in between or at the edge of HNTs layers give them potential to participate in epoxy ring-opening. Curing epoxy/anhydride systems containing HNTs at various concentrations (0.5, 1 and 2 wt.% based on 100 parts by weight of epoxy) via nonisothermal differential scanning calorimetry at three heating rates (5, 10 and 15 °C.min−1) is discussed here to study the effect of HNTs concentration on epoxy-anhydride curing reactions. The extent of crosslinking reaction was promoted at 0.5 and 1 wt.% of HNTs as a result of participation of hydroxyl groups of HNTs in epoxide ring-opening, while at 2 wt.% of HNTs a hindered curing was the case, which has been speculated on account of probable deactivation of anhydride curing agent by the internal surface of HNTs pursued by anhydride molecules diffusion into the lumen of HNTs.

Acid-degradable (or acid-cleavable) polymeric nanoassemblies have witnessed significant progress in anti-cancer drug delivery. However, conventional nanoassemblies designed with acid-cleavable linkages at a single location have several challenges, such as, sluggish degradation, undesired aggregation of degraded products, and difficulty in controlled and on-demand drug release. Herein, a strategy that enables the synthesis of acid-cleavable nanoassemblies labeled with acetaldehyde acetal groups in both hydrophobic cores and at core/corona interfaces, exhibiting synergistic response to acidic pH at dual locations and thus inducing rapid drug release is reported. The systematic analyses suggest that the acid-catalyzed degradation and disassembly are further enhanced by decreasing copolymer concentration (i.e., increasing proton/acetal mole ratio). Moreover, incorporation of acid-ionizable imidazole pendants in the hydrophobic cores improve the encapsulation of doxorubicin, the anticancer drug, through π-π interactions and enhance the acid-catalyzed hydrolysis of acetal linkages situated in the dual locations. Furthermore, the presence of the imidazole pendants induce the occurrence of core-crosslinking that compensates the kinetics of acetal hydrolysis and drug release. These results, combined with in vitro cell toxicity and cellular uptake, suggest the versatility of the dual location acid-degradation strategy in the design and development of effective intracellular drug delivery nanocarriers.

In this study, the effect of hybrid reinforcement comprising silica nanoparticles (SNPs) and a blend of equal percentages of acrylamide-modified waste tire powder and polyethylene terephthalate (PET) on mechanical, thermal stability, and microstructure of the epoxy-phenolic adhesive was assessed using tensile test, TGA, and FESEM tests, respectively. To investigate the adhesion features, the formulated adhesive was applied in lap joint bonding of a stainless steel 316L to epoxy resin/carbon fiber composite. Based on the tensile test results, adding 10 wt.% modified waste tire powder- PET blend and 1 wt.% SNPs to the epoxy-phenolic adhesive increased the tensile strength, modulus, and the toughness of the dumbbell-shaped samples by 65.24%, 58.95% and 98.80% as compared with the neat epoxy-phenolic adhesive, respectively. Furthermore, the highest improvement of shear strength, modulus, and toughness in the steel-composite single lap joint was observed in the sample containing 10 wt.% modified waste tire powder-PET blend and 0.5 wt.% SNPs of 237.22%, 25.64%, and 279.66%. TGA results also indicated that the addition of 10 wt.% PET powder and 1 wt.% SNPs enhanced the initial decomposition temperature, maximum decomposition temperature, and residue char by 5.94°C, 3.64°C, and 59.45% respectively. The images of the fracture surface of the optimal samples in the tensile test showed that the debonding of nanoparticles, plastic void growth, and deviation from the main crack path are among the major mechanisms in the increase of the toughness of the samples.

The development of heterogeneous covalent adaptable networks (CANs) embedded with carbon nanotubes (CNTs) that undergo reversible dissociation/recombination through thermoreversibility has been significantly explored. However, the carbon nanotube (CNT)-incorporation methods based on physical mixing and chemical modification could result in either phase separation due to structural incompatibility or degrading conjugation due to a disruption of π-network, thus lowering their intrinsic charge transport properties. To address this issue, the versatility of a macromolecular engineering approach through thermoreversibility by physical modification of CNT surfaces with reactive multidentate block copolymers (rMDBCs) is demonstrated. The formed CNTs stabilized with rMDBCs (termed rMDBC/CNT colloids) bearing reactive furfuryl groups is functioned as a multicrosslinker that reacts with a polymaleimide to fabricate robust heterogeneous polyurethane (PU) networks crosslinked through dynamic Diels-Alder (DA)/retro-DA chemistry. Promisingly, the fabricated PU network gels in which CNTs through rMDBC covalently embedded are flexible and robust to be bendable as well as exhibit self-healing elasticity and enhanced conductivity.

Properties of a rubber/clay nanocomposite coating depend on rubber network formed in the presence of clay platelets. Not surprisingly, however, a few is known about the state of cure in silicone nanocomposites. In this work, nanoclay flakes are modified with trifunctional silane, fully characterized, and then added to silicone coatings. The resulting nanocomposites are underwent nonisothermal differential scanning calorimetry (DSC) varying heating regime. Fourier-transform infrared spectrophotometry, X-ray diffractometry, and thermogravimetric analysis (TGA) techniques were employed to quantify grafting reaction efficiency and thermal stability of modified nanoclay. Cure characteristics of nanocomposites (exothermal peak temperature as well as cure enthalpy) containing pristine and silane-modified nanoclays were discussed in terms of clay content under different DSC heating rates. The mysterious state of cure in silicone/clay nanocomposite coatings was unraveled and then explained by solving curing puzzle for silicone/clay systems through comparison between newly defined T* and ΔH* dimensionless indexes dedicated to the crosslinked nanocomposite networks with respect to blank silicone coating. The progressive/diffusional crosslinking and complete/partial/imperfect curing were respectively evaluated by analyzing fluctuations in T* and ΔH* values, where the effects of clay content and surface chemistry were satisfactorily quantified.

Background: Traditional Persian Medicine (TPM) has a history of almost 10,000 years with practice and experience aspects. The existing information and experiences of physicians such as Avicenna clearly show the vast amount of knowledge in the classification and treatment of pathogenic worms. The aim of this paper was the description of the various types of helminths along with their treatment in medieval Persia and comparing them with new medical findings. Materials and Methods: We searched main Traditional Persian Medical and pharmacological texts about etiology, manifestation, diagnosis and treatment of worms in the human digestive system and the out come was compared with the data extracted from modern medical sources. A list of medicinal plants was also extracted from traditional pharmacological books and the anthelmintic properties of these plants were checked in Google Scholar, Scopus, PubMed and Ulrich's databases. Results: The results show the existence of theories on pathogenicity, physiopathology, symptoms and the classification of worms in TPM. TPM philosophers have divided worms into four groups and there is not great difference between old Persian and Modern classification. The old Persian scholars have explained a treatment procedure using a list of 48 medicinal plants and the anthelmintic effect of 23 plants have been shown in modern medicine studies. Conclusion: This study shows a more in-depth and thorough classification of pathogenic worms, their pathogenicity, symptoms and treatments in Traditional Persian Medical compared to Greek Medicine so that old Persian classification may be the base of modern taxonomy. More clinical trials are suggested for the efficacy and safety of these plants.

Poly(vinyl alcohol) (PVA) hydrogel membranes were prepared through three different preparation methods including freeze-thawing (FT), solution casting (SC) followed by thermal annealing, and phase separation (PS). The prepared hydrogels were characterized by Fourier transform-infrared spectroscopy, X-ray diffractometry, and scanning electron microscopy. Nitrofurazone (NFZ) was then loaded in the hydrogels. FT and SC methods led to obtaining dense membranes, while PS method resulted in an asymmetric one. The effects of hydrogel preparation method on water absorption, gel fraction, water vapor and oxygen permeabilities, bacterial barrier, tensile properties, and drug release profiles were investigated. The water vapor permeability of the hydrogel prepared through PS method was about 1.5 times higher than those obtained through FT and SC methods. Gel formation in PS method is probably responsible for the highest degree of crystallinity, and consequently the maximum gel fraction for the corresponded membrane. The elongation-at-break for this membrane in wet state was 41% higher than that made by FT method and 18% greater than that of SC method. Membranes prepared by all three methods showed excellent barrier property against bacterial penetration during 1 week. The results showed that PS membrane could control the release of NFZ more effectively as compared with the other two samples.

Acid-responsive degradable nanoassemblies self-assembled from amphiphilic block copolymers with acid-labile linkages have been extensively explored as effective intracellular drug delivery vehicles for chemotherapy. They degrade in tumoral and endo/lysosomal acidic environments (pH = 4.0–6.9), leading to enhanced/controlled release of encapsulated or conjugated drug molecules. In particular, imine (C=N) and its family of benzoic imine, hydrazone, and oxime are promising acid-labile linkages owning to their facile synthesis and tunable acid-responsive degradation. This review summarizes the recent advances in the design and synthesis of imine-bearing block copolymers and their nanoassemblies in three typical forms as self-assembled nanoassemblies, core-crosslinked nanogels, and polymer-drug conjugates. Numerous synthetic strategies to synthesize effective nanoassemblies with different numbers and locations of imine linkages are focused to elucidate their disassembly mechanism and enhanced drug release in acidic tumor environments.