Hyperbranched Block Copolymers Research Articles

High-flux and chlorine-resistant nanofiltration membrane fabricated via phase inversion using polysulfone-b-polyglycerol hyperbranched block copolymer

The nanofiltration (NF) membranes having excellent chlorine resistance and sufficient perm-selectivity are highly desired in drinking water treatment and other applications. Herein, a novel block copolymer NF membrane with superior chlorine resistance, especially high water permeance was prepared via phase inversion, using a tailor-made polysulfone-block-hyperbranched polyglycerol (PSf-b-hPG) material. The fabricated PSf-b-hPG NF membrane shows an extremely thin separation layer with a thickness of around 80 nm and a high overall porosity of 65 %, thanks to the structural advantage of hyperbranched hydrophilic hPG segments and the unique feature of the PSf-b-hPG casting solution of possessing a very low viscosity at a high solid content. The membrane exhibits an effective pore diameter of 1.6 nm, and the molecular weight cut-off (MWCO) was around 4 kDa. The membrane displayed extremely high pure water permeance of 34 LMH/bar as well as a satisfactory Na2SO4 rejection of 74 %. Moreover, the membrane exhibits superior chlorine resistance with no change in separation performance when challenged with 36,000 ppm∙h chlorination intensity and also maintains a stable Na2SO4 rejection and water permeance during the 14 h NF test. Our results suggest the NF membrane prepared by PSf-b-hPG has superior chlorine resistance and high water permeance, and is capable of efficiently removing sulfate from drinking water or others.

Cavitation-Mediated Fracture Energy Dissipation in Polylactide at Rubbery Soybean Oil-Based Block Copolymer Interfaces Formed via Reactive Extrusion.

Here, we spearhead a new approach to biopolymer impact modification that demonstrates superior performance while maintaining greater than 99% compostability. Using soybean-based monomers, a virtually untapped resource in terms of commercial volume and overall cost, a series of hyperbranched block copolymers were synthesized and melt-processed with poly(l-lactide) (PLA) to yield impact resistant all-polymer composites. Although PLA impact modification has been treated extensively, to date, the only practical solutions have relied on non-compostable petroleum-based rubbers. This study illustrates the activity of energy dissipation mechanisms such as cavitation, classically relegated to well-entangled petroleum-based rubbers, in poorly entangled hyperbranched soybean-based rubbers. Furthermore, we present a complete study of the mechanical performance and morphology of these impact modified PLA composites. The significance of combining deformation theory with a scalable green alternative to petroleum-based rubbers opens up a potential avenue for cheap compostable engineering thermoplastics.

Efficient Synthesis and Self-Assembly of Segmented Hyperbranched Block Copolymers via RAFT-Mediated Dispersion Polymerization Using Segmented Hyperbranched Macro-RAFT Agents

Efficient Synthesis and Self-Assembly of Segmented Hyperbranched Block Copolymers via RAFT-Mediated Dispersion Polymerization Using Segmented Hyperbranched Macro-RAFT Agents

Polyester-Polysiloxane Hyperbranched Block Polymers for Transparent Flexible Materials.

Highly transparent flexible silicone elastomers are useful for certain stretchable electronics and various types of smart devices. Polyester–polysiloxane hyperbranched block copolymers are synthesized by ring-opening polymerization of octamethylcyclotetrasiloxane initiated by macromolecular lithium alkoxide. Treatment of these copolymers with tetraethoxysilane and dibutylin dilaurate at room temperature gives the corresponding transparent elastic materials. The transparency of the materials can reach 90% (700–800 nm), and the starting thermal decomposition temperatures of the materials are higher than 330 °C. Very interestingly, though the highest tensile strength of the material prepared is about 0.48 MPa, the elongation at break can reach 778–815%. The results will inspire us to develop highly transparent flexible silicone materials by designing copolymers of silicone materials and hyperbranched polymers.

Degradable and cationic long-subchain hyperbranched block copolymers with well-defined block subchain: Synthesis, characterization and degradation

Self-assembly of long-subchain hyperbranched block copolymer (hyperblock) could achieve a novel micelle with multiple hydrophobic cores (multi-core micelle), while the hydrophobic components are generally consecutive in the core or shell of an independent conventional assembly. However, only a few studies focus on the synthetic methods and structure–property relationship of hyperblock. In this work, a degradable and cationic hyperblock with well-defined block subchain was prepared via seesaw-type macromonomer strategy. To improve the control of block subchain structure, degradable and pre-cationic block macromonomer with one alkynyl group in the chain middle and two azide groups at both chain ends, i.e. alkynyl-(PLA-b-PBocAEA-N3)2, was deliberately designed and synthesized via the combination of ring-opening polymerization, atom transfer radical polymerization and azidation. After “click” polymerization, degradable and pre-cationic hyperblock of lhb-(PLA-b-PBocAEA) were achieved, which is further modified with PEG and confirmed the degradation property. Finally, degradable and cationic hyperblock lhb-(PLA-b-PAEA)-g-PEG was obtained by deprotection of amino groups. All the intermediates and products were confirmed by NMR, FT-IR and GPC measurements.

Effect of block sequence of hyperbranched block copolymers on the aggregation behavior, drug solubilization and release property

Two hyperbranched block copolymers H904 and H90R4 which were the same in chemical composition but different in block sequence were synthesized by anionic polymerization. Commercially X shaped Tetronic block copolymers T904 and T90R4 were selected for comparison. The effect of block sequence on the aggregation behaviors of these four copolymers were studied by surface tension, transmission electron microscopy, steady-state fluorescence and dynamic light scattering. Compared with H904 and T904, higher critical aggregation concentration, the greater hydrophobicity and smaller size of the aggregates were the characteristics of the reverse sequence copolymers H90R4 and T90R4. The ability of copolymer aggregates to encapsulate and in vitro release of a hydrophobic drug olmesartan medoxomil (OM) were also evaluated. The smaller size of H90R4 and T90R4 aggregates resulted in much lower drug solubilization. However, the more tightly packing of H90R4 and T90R4 aggregates led to a stronger interaction between OM and aggregates, so the release of OM from H90R4 and T90R4 were slower. Besides, H904 and H90R4 spontaneously formed vesicles in aqueous solution, while T904 and T90R4 formed micelles. The block order and hyperbranched architecture of the block copolymers had great effects on their aggregation behavior, drug solubilization and release property.

Optimization of bioreducible micelles self‐assembled from amphiphilic hyperbranched block copolymers for drug delivery

ABSTRACTDendritic polymers‐based unimolecular micelles with enhanced stability are attractive carriers. However, the preparation of dendrimers or dendrons with higher generation remains substantially synthetic challenge due to the increased steric hindrance, multistep and tedious preparation, and low yields. The adoption of Boltorn H40, a commercially available dendritic polymer of Boltorn family containing multiple hydroxyl groups with various functionalities as a dendrimer‐based starting core template for the generation of hyperbranched polymers, offers a straightforward solution to address this problem. To develop universal strategies toward H40‐based amphiphilic block copolymers, the “grafting from” and “grafting to” approaches were both applied in this study. The reduction‐insensitive block copolymers, H40‐b‐poly(ɛ‐caprolactone)‐b‐poly(oligo(ethylene glycol) monomethyl ether methacrylate) (H40‐b‐PCL‐b‐POEGMA), were synthesized by “grafting from” including sequential ring‐opening polymerization (ROP) and atom transfer radical polymerization (ATRP). The core structure and the polymer composition of the nonreducible amphiphilic hyperbranched block copolymers were optimized toward better properties and performance for drug delivery applications, and H40‐PCL15‐b‐POEGMA23 was screened as the best polymer construct relative to H20‐PCL15‐b‐POEGMA23 and H40‐PCL15‐b‐POEGMA32 in terms of micelle stability and drug loading capacity. Therefore, the reducible H40‐b‐PCL‐SS‐POEGMA with an identical core and polymer composition to that of H40‐PCL15‐b‐POEGMA23 was further prepared by “grafting to” using click coupling between H40‐PCL‐azide and P(OEGMA)‐alkyne. The delivery efficacy evaluated by an in vitro cytotoxicity study revealed that the resulting DOX‐loaded reducible micelles of H40‐PCL15‐SS‐POEGMA23 produced greater cytotoxicity in cancer cells than in normal cells and macrophages, therefore, are promising carriers for anticancer drug delivery. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1383–1394

Development of a fast curing tissue adhesive for meniscus tear repair

Isocyanate-terminated adhesive amphiphilic block copolymers are attractive materials to treat meniscus tears due to their tuneable mechanical properties and good adhesive characteristics. However, a drawback of this class of materials is their relatively long curing time. In this study, we evaluate the use of an amine cross-linker and addition of catalysts as two strategies to accelerate the curing rates of a recently developed biodegradable reactive isocyanate-terminated hyper-branched adhesive block copolymer prepared from polyethylene glycol (PEG), trimethylene carbonate, citric acid and hexamethylene diisocyanate. The curing kinetics of the hyper-branched adhesive alone and in combination with different concentrations of spermidine solutions, and after addition of 2,2-dimorpholinodiethylether (DMDEE) or 1,4-diazabicyclo [2.2.2] octane (DABCO) were determined using FTIR. Additionally, lap-shear adhesion tests using all compositions at various time points were performed. The two most promising compositions of the fast curing adhesives were evaluated in a meniscus bucket handle lesion model and their performance was compared with that of fibrin glue. The results showed that addition of both spermidine and catalysts to the adhesive copolymer can accelerate the curing rate and that firm adhesion can already be achieved after 2 h. The adhesive strength to meniscus tissue of 3.2–3.7 N was considerably higher for the newly developed compositions than for fibrin glue (0.3 N). The proposed combination of an adhesive component and a cross-linking component or catalyst is a promising way to accelerate curing rates of isocyanate-terminated tissue adhesives.

Construction and properties of hyperbranched block copolymer with independently adjustable hetero-subchains

Construction and properties of hyperbranched block copolymer with independently adjustable hetero-subchains

Architecture‐controlled synthesis of redox‐degradable hyperbranched polyglycerol block copolymers and the structural implications of their degradation

ABSTRACTWe have successfully synthesized a series of redox‐degradable hyperbranched polyglycerols using a disulfide containing monomer, 2‐((2‐(oxiran‐2‐ylmethoxy)ethyl)disulfanyl) ethan‐1‐ol (SSG), to yield PSSG homopolymers and hyperbranched block copolymers, P(G‐b‐SSG) and P(SSG‐b‐G), containing nondegradable glycerol (G) monomers. Using these polymers, we have explored the structures of the hyperbranched block copolymers and their related degradation products. Furthermore, side reaction such as reduction of disulfide bond during the polymerization was investigated by employing the free thiol titration experiments. We elucidated the structures of the degradation products with respect to the architecture of the hyperbranched block copolymer under redox conditions using 1H NMR and GPC measurements. For example, the degradation products of P(G‐b‐SSG) and P(SSG‐b‐G) are clearly different, demonstrating the clear distinction between linear and hyperbranched block copolymers. We anticipate that this study will extend the structural diversity of PG based polymers and aid the understanding of the structures of degradable hyperbranched PG systems. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 1752–1761

Chain Architecture as an Orthogonal Parameter To Influence Block Copolymer Morphology. Synthesis and Characterization of Hyperbranched Block Copolymers: HyperBlocks

For block copolymers there is usually a strong correlation between the copolymer composition (volume fraction of each block) and the resulting solid state morphology. However, for a variety of potential applications, e.g., semipermeable membranes or templates, it might be desirable to vary the microphase morphology independently of copolymer composition. The use of chain branching is an additional and orthogonal parameter to influence morphology, independently of composition, and we explore for the first time the impact of a long-chain, hyperbranched architecture on the microphase-separated, solid state morphology of branched block copolymers. To this end, a series of functionalized linear ABA (polystyrene–polyisoprene–polystyrene) triblock copolymers (macromonomers), hyperbranched ABA triblock copolymers (HyperBlocks), and blends of HyperBlocks with a commercially available linear ABA triblock copolymeric thermoplastic elastomer were prepared. Moreover, the “macromonomer” approach is the only feasible route to prepare hyperbranched block copolymers. The solid state morphology of the resulting materials was investigated by a combination of transmission electron microscopy (TEM) and small-angle X-ray scattering (SAXS) which showed a dramatic impact of the chain architecture on the resulting morphology. While the linear ABA triblock copolymers showed the expected microphase-separated morphology with long-range order dependent upon composition, no long-range order was observed in the HyperBlocks. Instead, the HyperBlocks revealed a microphase-separated morphology without long-range lattice order, irrespective of macromonomer composition or molecular weight. Furthermore, when HyperBlocks were subsequently blended with a commercially available linear ABA triblock copolymer (Kraton D1160), the HyperBlock appeared to impose a microphase-separated morphology without long-range lattice order upon the linear copolymer even when the HyperBlock is present as the minor component in the blend at levels as low as 10 wt %.

Synthesis of hyperbranched polymers and hyperbranched block copolymers through “A2 + B3” click reaction

Long-chain hyperbranched and hyperbranched block polymers were synthesized through Cu catalyzed azide-alkyne cycloaddition (CuAAC) of A2 macromonomers with two alkyne groups and B3 coupling reagent with three azide groups. Polystyrene (PSt) homopolymers and block copolymers of styrene and butyl acrylate (P(St-b-BA-b-St)) with two alkyne groups were obtained via reversible addition-fragmentation chain transfer (RAFT) polymerization using a RAFT agent with two alkyne groups, S, S′-bis(α, α′-dimethyl – α″-propargyl acetate) trithio carbonate (BPTTC). Besides, the hyperbranched block copolymers were also prepared through the successive RAFT polymerization of BA with the hyperbranched PSt as RAFT agents. The evidence of 1H NMR, IR and GPC-Viscosity-MALLS measurements conformed the structure of the polymers. Dpws, the ratio of the weight average molecular weights of the hyperbranched polymers to those of the macromonomers, reached above 60 at most, calculated from MALLS measurement, which showed a high degree of the coupling reaction. The degree of branched of the hyperbranched polymers kept on increasing with the reaction time, according to the branching factor, g′.

Hyperbranched block copolymer from AB2 macromonomer: Synthesis and its reaction‐induced microphase separation in epoxy thermosets

ABSTRACTIn this contribution, we reported the synthesis of a hyperbranched block copolymer composed of poly(ε‐caprolactone) (PCL) and polystyrene (PS) subchains. Toward this end, we first synthesized an α‐alkynyl‐ and ω,ω′‐diazido‐terminated PCL‐b‐(PS)2 macromonomer via the combination of ring‐opening polymerization and atom transfer radical polymerization. By the use of this AB2 macromonomer, the hyperbranched block copolymer (h‐[PCL‐b‐(PS)2]) was synthesized via a copper‐catalyzed Huisgen 1,3‐dipolar cycloaddition (i.e., click reaction) polymerization. The hyperbranched block copolymer was characterized by means of 1H nuclear magnetic resonance spectroscopy and gel permeation chromatography. Both differential scanning calorimetry and atomic force microscopy showed that the hyperbranched block copolymer was microphase‐separated in bulk. While this hyperbranched block copolymer was incorporated into epoxy, the nanostructured thermosets were successfully obtained; the formation of the nanophases in epoxy followed reaction‐induced microphase separation mechanism as evidenced by atomic force microscopy, small angle X‐ray scattering, and dynamic mechanical thermal analysis. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 368–380

Synthesis and characterization of hyperbranched amphiphilic block copolymers prepared via self‐condensing RAFT polymerization

ABSTRACTFour families of hyperbranched amphiphilic block copolymers of styrene (Sty, less polar monomer) and 2‐vinylpyridine (2VPy, one of the two more polar monomers) or 4‐vinylpyridine (4VPy, the other polar monomer) were prepared via self‐condensing vinyl reversible addition‐fragmentation chain transfer polymerization (SCVP‐RAFT). Two families contained 4VPy as the more polar monomer, one of which possessing a Sty‐b‐4VPy architecture, and the other possessing the reverse block architecture. The other two families bore 2VPy as the more polar monomer and had either a 2VPy‐b‐Sty or a Sty‐b‐2VPy architecture. Characterization of the hyperbranched block copolymers in terms of their molecular weights and compositions indicated better control when the VPy monomers were polymerized first. Control over the molecular weights of the hyperbranched copolymers was also confirmed with the aminolysis of the dithioester moiety at the branching points to produce linear polymers with number‐average molecular weights slightly greater than the theoretically expected ones, due to recombination of the resulting thiol‐terminated linear polymers. The amphiphilicity of the hyperbranched copolymers led to their self‐assembly in selective solvents, which was probed using atomic force microscopy and dynamic light scattering, which indicated the formation of large spherical micelles of uniform diameter. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 1310–1319

Construction and Properties of Hyperbranched Block Copolymer with Independently Adjustable Heterosubchains

A trifunctional initiator with one alkyne, one hydroxyl, and one bromine group was used to construct Br-polystyrene-alkyne-poly(ε-caprolactone)-OH (Br–PS–≡–PCL–OH) diblock copolymer precursor with one terminal alkyne group located at the junction between the two blocks. Further bromination and azidation substitution of the precursor led to a seesaw-type macromonomer azide-polystyrene-alkyne-poly(ε-caprolactone)-azide (N3–PS–≡–PCL–N3). Subsequently, novel hyperbranched copolymers [HB-(PS-b-PCL)n] with independently adjustable PS and PCL branching subchains were prepared by “click” chemistry. All of the linear precursors and hyperbranched copolymers were characterized by FT-IR, 1H NMR, and GPC with triple detectors in detail. It was found that such hyperbranched copolymers are self-similar objects; namely, their intrinsic viscosities ([η]) are scaled to the weight-average molar masses (Mw) as [η] ∼ Mwν, where ν = 0.45 ± 0.01 and 0.48 ± 0.01 for the longer and shorter PS block, respectively. Moreover, the study on the crystallization behavior of unfractionated and fractionated HB-(PS-b-PCL)n copolymers indicated both the crystal size and the degree of crystallinity decrease with the PS subchain length and the overall degree of polymerization, and the remaining oligomer and macromonomer components could facilitate the crystallization of the unfractionated sample. Finally, it was found that the degree of crystallinity decreases dramatically when the weight fraction of fractionated hyperbranched copolymer in macromonomer/hyperbranched copolymer blend films exceeds ∼67%, indicating that the uncrystallizable hyperbranched chains may impose some extra restriction on the crystallization of the macromonomer chains.

PH-responsive unimolecular micelles self-assembled from amphiphilic hyperbranched block copolymer for efficient intracellular release of poorly water-soluble anticancer drugs

Novel unimolecular micelles from amphiphilic hyperbranched block copolymer H40-poly(ε-caprolactone)-b-poly(acrylic acid)-b′-methoxy poly(ethylene glycol)/poly(ethylene glycol)-folate (i.e., H40-PCL-b-PAA-b′-MPEG/PEG-FA (HCAE-FA)) as new multifunctional nanocarriers to pH-induced accelerated release and tumor-targeted delivery of poorly water-soluble anticancer drugs were developed. The hydrophobic core of the unimolecular micelle was hyperbranched polyester (H40-poly(ε-caprolactone) (H40-PCL)). The inner hydrophilic layer was composed of PAA segments, while the outer hydrophilic shell was composed of PEG segments. This copolymer formed unimolecular micelles in the aqueous solution with a mean particle size of 33nm, as determined by dynamic light scattering (DLS) and transmission electron microscopy (TEM). To study the feasibility of micelles as a potential nanocarrier for targeted drug delivery, we encapsulated a hydrophobic anticancer drug, paclitaxel (PTX), in the hydrophobic core, and the loading content was determined by UV–vis analysis to be 10.35wt.%. In vitro release studies demonstrated that the drug-loaded delivery system is relatively stable at physiologic conditions but susceptible to acidic environments which would trigger the release of encapsulated drugs. Flow cytometry and fluorescent microscope studies revealed that the cellular binding of the FA-conjugated micelles against HeLa cells was higher than that of the neat micelles (without FA). The in vitro cytotoxicity studies showed that the PTX transported by these micelles was higher than that by the commercial PTX formulation Tarvexol®. All of these results show that these unique unimolecular micelles may offer a very promising approach for targeted cancer therapy.

The synthesis and solution properties of hyperbranched polyglycerols modified with hexafluorobutyl acrylate

A series of well-defined fluorinated hyperbranched block copolymers poly(glycerol)-b-poly(hexafluorobutyl acrylate) (PG-b-PHFBA) were prepared by atom transfer radical polymerization (ATRP) of 2,2,3,4,4,4-hexafluorobutyl acrylate (HFBA) in THF, using bromoester-terminated hyperbranched polyglycerol (PG-g-Br) as a macroinitiator. 1H NMR, 13C NMR, 19F NMR, GPC, FT-IR were employed to characterized the molecular structure of PG-b-PHFBA. The surface properties and micellization behavior of the copolymers in ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]) was studied by surface tension measurements and dynamic light scattering (DLS). The results showed that the copolymers in ILs could depress surface tension in a manner analogous to aqueous solutions, and the γCMC and critical micelle concentration (CMC) of the multiarm copolymers decreased with the increase of the PHFBA arm length. The DLS results demonstrated that the copolymer formed unimolecular micelles in ILs at the lower concentration, and two kinds of aggregates with Dh 0.7–3nm and 100–500nm were detected at higher concentrations.

Combining Ring-Opening Multibranching and RAFT Polymerization: Multifunctional Linear–Hyperbranched Block Copolymers via Hyperbranched Macro-Chain-Transfer Agents

The synthesis of a hyperbranched macro-chain-transfer agent for RAFT polymerization of functional methacrylate or methacrylamide monomers was achieved by selectively attaching one single CTA onto hyperbranched polyglycerol dendron analogues. The combination of ring-opening multibranching polymerization of glycidol and subsequent RAFT polymerization of the hyperbranched macro-chain-transfer agents created a new route to a variety of multifunctional linear–hyperbranched block topologies. All linear–hyperbranched block copolymers could be synthesized with controlled molecular weight (Mn = 3.2–43.7 kg/mol) and low polydispersity (PDI = 1.15–1.34). As first examples for this universal approach, we present block copolymer syntheses with thermoresponsive methacrylate (tri(ethylene glycol) methyl ether methacrylate) and biocompatible methacrylamide (2-hydroxypropylmethacrylamide). Because of the presence of dithiobenzoate esters at the end of each linear polymer chain end, selective end-group modification with fu...

Gold Nanocluster-Conjugated Amphiphilic Block Copolymer for Tumor-Targeted Drug Delivery

Two kinds of core-shell structured multifunctional nanocarriers of gold nanoclusters (Au NCs) as core and folate (FA)-conjugated amphiphilic hyperbranched block copolymer as shell based on poly(L-lactide) (PLA) inner arm and FA-conjugated sulfated polysaccharide (GPPS-FA) outer arm (Au NCs-PLA-GPPS-FA) were synthesized for targeted anticancer drug delivery. The structure and properties of Au NCs-PLA-GPPS-FA copolymers were characterized and determined by ¹H NMR spectrum, FT-IR spectra, dynamic light scattering (DLS), fluorescence spectroscopy, and transmission electron microscopic (TEM) analyses. The anticancer drug, camptothecin (CPT) was used as a hydrophobic model anticancer drug. In vitro, two kinds of the nanocarriers presented a relatively rapid release in the first stage (up to 1 h) followed by a sustained release period (up to 15 h), and then reached a plateau at pH 5.3, 7.4, and 9.6. The release results indicated that CPT release from two kinds of the nanocarriers at pH 9.6 was much greater than that at both pH 5.3 and 7.4. The cytotoxicity studies showed that the CPT-loaded nanocarriers provided high anticancer activity against Hela cells. Furthermore, nanocarriers gained specificity to target some cancer cells because of the enhanced cell uptake mediated by FA moiety. The fluorescent images studies showed that the nanocarriers could track at the cellular level for advance therapy. The results indicated that the Au NCs-PLA-GPPS-FA copolymers not only had great potential as tumor-targeted drug delivery carrier, but also had an assistant role in the treatment of cancer.

Core–shell nanocarriers with ZnO quantum dots-conjugated Au nanoparticle for tumor-targeted drug delivery

Core–shell structured multifunctional nanocarriers (NCs) of ZnO quantum dots-conjugated gold nanoparticles (Au NPs) as core and amphiphilic hyperbranched block copolymer as shell were synthesized for targeted anticancer drug delivery. The amphiphilic hyperbranched block copolymer contained poly(l-lactide) (PLA) inner arm and folate (FA)-conjugated a sulfated polysaccharide from Gynostemma pentaphyllum Makino (GPPS-FA) outer arm. The structure and properties of core–shell structured multifunctional nanocarriers were characterized and determined by UV–visible spectra, FT-IR spectra, X-ray diffraction (XRD), fluorescence spectroscopy and TEM analyses. The release results indicated that camptothecin (CPT) release from NCs at pH 7.4 was much greater than that at pH 5.3. The cytotoxicity studies showed that both the blank NCs and the CPT-loaded NCs provided high anticancer activity against Hela cells. Furthermore, nanocarriers gained specificity to target model cancer cells in this study due to the enhanced cell uptake mediated by FA moiety. The results indicated that the NCs not only had great potential as tumor-targeted drug delivery nanocarrier, but also had an assistant role in the treatment of cancer.