Modification of a polyethersulfone membrane with a block copolymer brush of poly(2-methacryloyloxyethyl phosphorylcholine-co-glycidyl methacrylate) and a branched polypeptide chain of Arg–Glu–Asp–Val

Polyethersulfone (PES) has good thermal stability, superior pH, chlorine tolerance, and excellent chemical resistance; however, the hydrophilicity and biocompatibility of PES need to be improved for its real applications. In this study, we report a surface modification method for the preparation of a functional PES membrane with hydrophilic polymer chains (MPC and GMA) via surface-initiated electrochemically-mediated atom-transfer radical polymerization (SI-eATRP) technology, and the Arg–Glu–Asp–Val polypeptide groups (REDV) were immobilized onto the modified membrane by a ring-opening reaction. XPS and SEM were used to analyze the chemical composition and morphology of the modified membrane surfaces, confirming that the hydrophilic polymer chains MPC and GMA and the polypeptide group REDV were successfully grafted onto the PES membrane surface. The static water contact angle decreased from 89° to 50–65°, and the hydrophilic property of the modified membrane was enhanced. The water flux increased from 4.29 L m⁻² h⁻¹ for the pristine PES membrane to 25 L m⁻² h⁻¹ for the modified membrane with PGMA chains grafted on it and REDV functional groups immobilized on it; note that the antifouling tests showed that all the modified membranes had the higher flux recovery ratio values (FRR) of above 80% than the pristine PES membrane (about 60%), and the APTT for the modified membrane increased from 46 s to 93 s, indicating that these modified membranes could be applied in the separation and blood purification fields.

A block copolymer involving chains of poly(2-methacryloyloxyethyl phosphorylcholine-co-glycidyl methacrylate) and Arg–Glu–Asp–Val was designed and used for modification of polymer membrane for applications in separation and blood purification field.     

Synthesis of biodiesel from waste cooking oil catalyzed by β-cyclodextrin modified Mg–Al–La composite oxide

In this study, Mg–Al–La composite oxide loaded with ionic liquid [Bmim]OH was used as a catalyst for the synthesis of fatty acid isobutyl ester (FAIBE) via transesterification between waste cooking oil and isobutanol. Mg–Al–La composite oxide was synthesized from the β-cyclodextrin (β-CD) intercalation modification of Mg–Al–La layered double hydroxides. The structure of the catalyst was characterized via XRD, BET and EDS. The results showed that the interlayer space of the catalyst was increased due to β-CD intercalation modification. The IL/CD–Mg–Al–La catalyst exhibited significant catalytic activity and regeneration performance in transesterification due to large interlayer space and strongly alkaline ionic liquid. The yield of FAIBE achieved was 98.3% under the optimum reaction condition and 95.2% after regeneration for six times. The viscosity–temperature curve of FAIBE was determined and the phase transition temperature was −1 °C. The pour point of FAIBE was only −10 °C, which exhibited excellent low temperature fluidity.

In this study, Mg–Al–La composite oxide loaded with ionic liquid [Bmim]OH was used as a catalyst for the synthesis of fatty acid isobutyl ester (FAIBE) via transesterification between waste cooking oil and isobutanol.     

Proton–deuterium exchange of acetone catalyzed in imidazolium-based ionic liquid–D2O mixtures

The reaction of the proton–deuterium exchange of acetone in imidazolium-based ionic liquid (IL)–deuterium oxide mixtures was studied in detail via NMR spectroscopy. Certain ILs exhibit considerable catalytic properties and contribute to the course of reaction up to the complete deuteration. The efficiency of deuterium exchange crucially depends on the features of ILs; the type of anion and chain length of cation. The linear secondary isotope effects on the NMR chemical shifts of the ¹³C atoms in acetone were observed depending on the deuteration level of the molecule.

The reaction of the proton–deuterium exchange of acetone in imidazolium-based ionic liquid (IL)–deuterium oxide mixtures was studied in detail via NMR spectroscopy.     

Facile preparation of porous sheet–sheet hierarchical nanostructure NiO/Ni–Co–Mn–Ox with enhanced specific capacity and cycling stability for high performance supercapacitors

NiO, Ni–Co–Mn–O_x and NiO/Ni–Co–Mn–O_x on nickel foam substrates were prepared via a chemical bath deposition–calcination. The thermodynamic behavior was observed by TG/DTA. The chemical structure and composition, phase structure and microstructures were tested by XPS, XRD, FE-SEM and TEM. The electrochemical performance was measured by CV, GCD and EIS. The mechanism for formation and enhancing electrochemical performance is also discussed. Firstly, the precursors such as NiOOH, CoOOH and MnOOH grow on nickel foam substrates from a homogeneous mixed solution via chemical bath deposition. Thereafter, these precursors are calcined and decomposed into NiO, Co₃O₄ and MnO₂ respectively under different temperatures in a muffle furnace. Notably, NiO/Ni–Co–Mn–O_x on nickel foam substrates reveals a high specific capacity with 1023.50 C g⁻¹ at 1 A g⁻¹ and an excellent capacitance retention with 103.94% at 5 A g⁻¹ after 3000 cycles in 2 M KOH, its outstanding electrochemical performance and cycling stability are mainly attributed to a porous sheet–sheet hierarchical nanostructure and synergistic effects of pseudo-capacitive materials and excellent redox reversibility. Therefore, this research offers a facile synthesis route to transition metal oxides for high performance supercapacitors.

NiO, Ni–Co–Mn–O_x and NiO/Ni–Co–Mn–O_x on nickel foam substrates were prepared via a chemical bath deposition–calcination.     

Study on the synthesis and thermal stability of silicone resins reinforced by Si–O–Ph cross-linking

A novel silicone resin (SR-OH) containing phenolic hydroxyl (Ph–OH) groups was designed and synthesized via co-hydrolysis/condensation and catalytic hydrogenation. During the curing process, the cross-linking degree of the resin was further increased by the Si–O–Ph bonds formed by the reaction of the Ph–OH and terminal Si–OH groups. Thermogravimetric analysis (TGA) showed that the cured resin product exhibited excellent thermal and thermo-oxidative stability, which was much higher than that of a typical methyl phenyl silicone resin (SR-Ph). The temperature at which 5% weight loss occurs (T_d5) was up to 606 °C (nitrogen) and 542 °C (air), and its char yield at 800 °C was 91.1% and 85.3% in nitrogen and air, respectively. The significant improvement in thermal stability was mainly attributed to the formation of Si–O–Ph bonds which not only increases the cross-linking degree of the resin but also significantly prevents degradation by the ‘back-biting’ and oxidative cleavage.

A novel silicone resin (SR-OH) containing phenolic hydroxyl (Ph–OH) groups was designed and synthesized via co-hydrolysis/condensation and catalytic hydrogenation.     

Palladium-catalyzed intramolecular C–H arylation of 2-halo-N-Boc-N-arylbenzamides for the synthesis of N–H phenanthridinones

A palladium catalyzed synthesis of N–H phenanthridinones was developed via C–H arylation. The protocol gives phenanthridinones regioselectively by one-pot reaction without deprotection. It exhibits broad substrate scope and affords targets in up to 95% yields. Importantly, it could be applied for the less reactive o-chlorobenzamides.

Pd(t-Bu₃P)₂/KOAc proved to be a good combination for one-pot synthesis of N–H phenanthridinones with up to 95% yield.     

An approach to new chiral bicyclic imines and amines via Horner–Wadsworth–Emmons reaction

New chiral bicyclic imines, enamines and amines were prepared via Horner–Wadsworth–Emmons reaction of hexahydroquinoxalin-2(1H)-one-derived phosphonate, as the source of a phosphonate carbanion, and a wide range of structurally diverse carbonyl substrates. The simplicity of the synthetic protocol, high selectivity, and broad substrate scope are the main advantages of the presented methodology.

New chiral cyclic imines and enamines were prepared via HWE reaction, with selectivity dependent on the carbonyl substrate.     

Design,synthesis and in silico screening of benzoxazole–thiazolidinone hybrids as potential inhibitors of SARS-CoV-2 proteases

Hybrid molecules in the recent years have gained significant importance in drug research as promising therapeutic agents. We report a novel combination of two such bioactive scaffolds (benzoxazole and 4-thiazolidinone B–T hybrids) as inhibitors of SARS-CoV-2. The study uses an in silico approach to identify the potential of B–T hybrids as possible inhibitors of the SARS-CoV-2 proteases. Molecular docking was employed to identify the interactions of B–T hybrids with the two proteases – 3CLp (the 3-chymotrypsin-like protease) and PLp (the papain-like protease). Docking results of the screened 81 hybrids indicated that BT10 and BT14 interacted with the catalytic dyad residue of 3CLp (Cys145) with the best binding energy. MD simulations revealed that BT10 formed stable interactions via 4 hydrogen bonds with the catalytic site residues of 3CLp. In the case of PLp, BT27 and MBT9 interacted with the catalytic triad residue of PLp (His272) with high binding energy. MD simulations demonstrated that the reference drug Tipranavir relocated to the thumb region of the protease whereas BT27 remained in the active site of PLp stabilized by 2 hydrogen bonds, while MBT9 relocated to the BL2 loop of the palm region. The MM-PBSA and interaction entropy (IE) analysis indicated that BT14 exhibited the best ΔG (of −6.83 kcal mol⁻¹) with 3CLp, while BT27 exhibited the best ΔG (of −7.76 kcal mol⁻¹) with PLp. A four-step synthetic procedure was employed to synthesize the B–T hybrids starting from ammonium thiocyanate. The short-listed compounds in the case of 3CLp were synthesized and characterized using IR, NMR, and HRMS spectroscopic techniques.

A novel combination of two bioactive scaffolds – benzoxazole and 4-thiazolidinone (B–T hybrids) as potential inhibitors of SARS-CoV-2.     

Enhanced hydrogen storage properties of 1.1MgH2–2LiNH2–0.1LiBH4 system with LaNi5-based alloy hydrides addition

Significant improvements in the hydrogen sorption properties of the Li–Mg–N–H system have been achieved by adding a small amount of LiBH₄. Herein, the hydrogen storage properties of the 1.1MgH₂–2LiNH₂–0.1LiBH₄ system are further enhanced by addition of LaNi₅-based (LaNi_3.8Al_0.75Mn_0.45, LaNi_4.5Mn_0.5, LaNi₄Co) alloy hydrides. The refinement of the Li–Mg–B–N–H particles and the metathesis reaction are facilitated by adding LaNi₅-based alloy hydrides during the ball milling process. The addition of LaNi₅-based alloy hydrides can enhance the hydrogen sorption kinetics, reduce the dehydrogenation temperature and promote a more thorough dehydrogenation of the Li–Mg–B–N–H system. The LaNi₅-based alloy hydrides are involved in hydrogen de/hydrogenation reaction. Among the three alloys, LaNi_4.5Mn_0.5 makes the most obvious improvement on the reaction kinetics, and the dehydrogenation peak temperature is reduced by 12 °C, while the activation energy is reduced by 11% with 10 wt% LaNi_4.5Mn_0.5 addition. The weakening of the N–H bond and the homogeneous distribution of the LaNi₅-based alloy hydrides in the Li–Mg–B–N–H composite have important roles in the reduction of the desorption barrier and the kinetics enhancement.

The weakening of N–H bond and the homogeneous distribution of LaNi₅-based alloy hydrides in the Li–Mg–B–N–H composite enhance its hydrogen storage properties.     

Au–Ag and Pt–Ag bimetallic nanoparticles@halloysite nanotubes: morphological modulation,improvement of thermal stability and catalytic performance

In this study, Au–Ag and Pt–Ag bimetallic nanocages were loaded on natural halloysite nanotubes (HNTs) via galvanic exchange based on Ag@HNT. By changing the ratio of Au to Ag or Pt to Ag in exchange processes, Au–Ag@HNT and Pt–Ag@HNT with different nanostructures were generated. Both Au–Ag@HNT and Pt–Ag@HNT systems showed significantly improved efficiency as peroxidase-like catalysts in the oxidation of o-phenylenediamine compared with monometallic Au@HNT and Pt@HNT, although inert Ag is dominant in the composition of both Au–Ag and Pt–Ag nanocages. On the other hand, loading on HNTs enhanced the thermal stability for every system, whether monometallic Ag nanoparticles, bimetallic Au–Ag or Pt–Ag nanocages. Ag@HNT sustained thermal treatment at 400 °C in nitrogen with improved catalytic performance, while Au–Ag@HNT and Pt–Ag@HNT maintained or even had slightly enhanced catalytic efficiency after thermal treatment at 200 °C in nitrogen. This study demonstrated that natural halloysite nanotubes are a good support for various metallic nanoparticles, improving their catalytic efficiency and thermal stability.

Bimetallic Au–Ag@HNT and Pt–Ag@HNT nanocages showed significantly improved efficiency in the oxidation of o-phenylenediamine as peroxidase-like catalyst compared with corresponding monometallic nanoparticles.     

A novel MnO–CrN nanocomposite based non-enzymatic hydrogen peroxide sensor

A MnO–CrN composite was obtained via the ammonolysis of the low-cost nitride precursors Cr(NO₃)₃·9H₂O and Mn(NO₃)₂·4H₂O at 800 °C for 8 h using a sol–gel method. The specific surface area of the synthesized powder was measured via BET analysis and it was found to be 262 m² g⁻¹. Regarding its application, the electrochemical sensing performance toward hydrogen peroxide (H₂O₂) was studied via applying cyclic voltammetry (CV) and amperometry (i–t) analysis. The linear response range was 0.33–15 000 μM with a correlation coefficient (R²) value of 0.995. Excellent performance toward H₂O₂ was observed with a limit of detection of 0.059 μM, a limit of quantification of 0.199 μM, and sensitivity of 2156.25 μA mM⁻¹ cm⁻². A short response time of within 2 s was achieved. Hence, we develop and offer an efficient approach for synthesizing a new cost-efficient material for H₂O₂ sensing.

A MnO–CrN composite was obtained via the ammonolysis of the low-cost nitride precursors Cr(NO₃)₃·9H₂O and Mn(NO₃)₂·4H₂O at 800 °C for 8 h using a sol–gel method.     

In situ high pressure neutron diffraction and Raman spectroscopy of 20BaO–80TeO2 glass

The short-range structure of 20BaO–80TeO₂ glass was studied in situ by high pressure neutron diffraction and high pressure Raman spectroscopy. Neutron diffraction measurements were performed at the PEARL instrument of the ISIS spallation neutron source up to a maximum pressure of 9.0 ± 0.5 GPa. The diffraction data was analysed via reverse Monte Carlo simulations and the changes in the glass short-range structural properties, Ba–O, Te–O and O–O bond lengths and speciation were studied as a function of pressure. Te–O co-ordination increases from 3.51 ± 0.05 to 3.73 ± 0.05, Ba–O coordination from 6.24 ± 0.19 to 6.99 ± 0.34 and O–O coordination from 6.00 ± 0.05 to 6.69 ± 0.06 with an increase in pressure from ambient to 9.0 GPa. In situ high pressure Raman studies found that the ratio of intensities of the two bands at 668 cm⁻¹ and 724 cm⁻¹ increases from 0.99 to 1.18 on applying pressure up to 19.28 ± 0.01 GPa, and that these changes are due to the conversion of TeO₃ into TeO₄ structural units in the tellurite network. It is found that pressure causes densification of the tellurite network by the enhancement of co-ordination of cations, and an increase in distribution of Te–O and Ba–O bond lengths. The original glass structure is restored upon the release of pressure.

The short-range structure of 20BaO–80TeO₂ glass was studied in situ by high pressure neutron diffraction and high pressure Raman spectroscopy.     

The pioneering role of metal–organic framework-5 in ever-growing contemporary applications – a review

MOF-5 with a Zn(ii) cluster and terephthalic acid is a distinctive porous material among the metal–organic frameworks (MOFs), with unique physical, chemical and mechanical properties. MOF-5 based composites possess ample applications in modern chemistry. Huge surface area, suitable pore dimensions and scope of tunability make MOF-5 noteworthy in advanced materials. The extensive features of MOF-5 provided an opportunity for researchers to explore atomic/molecular scale materials. Various MOF-5 based composites have been designed with revamped properties appropriate to the application by altering and fabricating MOF-5 in situ or using a post-synthetic approach. Surface modification via the dispersion and impregnation of active substances into the pores of MOF-5 enhances its applicability. The boundless topologies and morphologies of MOF-5 combined with other chemical entities has provided opportunities in various fields, including catalysis, gas storage and sensors. The present review illuminates the leading role of MOF-5 and its composites in contemporary applications based on the current literature in heterogeneous catalysis, H₂ and CO₂ storage and sensors.

MOF-5 with a Zn(ii) cluster and terephthalic acid is a distinctive porous material among the metal–organic frameworks (MOFs), with unique physical, chemical and mechanical properties.     

Facile fabrication and low-temperature bonding of Cu@Sn–Bi core–shell particles for conductive pastes

The rapid development of flexible wearable electronics arouses huge demand for low-temperature sintering metal inks applied to temperature-sensitive substrates. The high sintering temperature and easy oxidation limited the application of Cu-based pastes. A two-step method involving liquid co-reduction and heat ripening was developed to synthesize Cu@Sn–Bi core–shell particles. The thickness of Sn–Bi shells can be flexibly adjusted via changing the mass ratio of Cu to Sn–Bi. The volume resistivity of printed circuits using Cu@Sn–Bi pastes solidified at 200 °C was as low as 481 μΩ cm, which increased by 11.8% after an aging process at 190 °C for 6 h. The outstanding stability in a harsh environment would attribute to the effective protection of Sn–Bi alloy shells. This work suggests a new pathway toward the low-temperature bonding and anti-oxidation of Cu particles as conductive fillers, which can be widely applied to the additive manufacturing of flexible wearable electronics.

Cu@Sn–Bi core–shell particles were synthesized and used as conductive fillers of ink applied to flexible printed circuits. This work provides new insights into the low-temperature bonding and anti-oxidation protection of Cu-based conductive pastes.     

Donor moieties with D–π–a framing modulated electronic and nonlinear optical properties for non-fullerene-based chromophores

Herein, a series of non-fullerene-based substantial chromophores (FHD1–FHD6) with a D–π–A framework was designed from a synthesized non-fullerene compound (FH) via structural tailoring with various donor moieties. The FH and its designed derivatives were optimized with frequency analysis at the M06/6-311G (d,p) level to confirm their true minima on potential energy surfaces. These optimized geometries were utilized to perform further analyses, such as absorption, natural bonding orbital (NBO), frontier molecular orbital (FMO), and nonlinear orbital (NLO) analyses at the aforesaid level. Quantum chemical study revealed that all the designed chromophores exhibited a lower band gap than that of the parent molecule with the exception of FHD3. Furthermore, density of states (DOS) analysis supported the findings from the FMO study, and this agreement revealed that the efficient charge was transferred from the HOMO to the LUMO. The NBO investigations disclosed that all the compounds comprised donor moieties with positive charges and acceptors having negative charges. Interestingly, π-conjugated linkers were also found with positive charges, showing an effective donating property. These NBO findings explicated that FHD1–FHD6 exhibited an efficient push–pull mechanism. The λ_max values of the designed chromophores were observed to be greater than the reference compound. The average polarizability 〈α〉, first hyperpolarizability (β_tot), and second hyperpolarizability 〈γ〉 values of FHD2 were found to be 2.170 × 10⁻²², 3.150 × 10⁻²⁷, and 4.275 × 10⁻³² esu, respectively, while all the other derivatives had been reported in the relevant range. Efficient NLO data revealed that FH-based derivatives may contribute significantly toward NLO technology.

Herein, a series of non-fullerene-based substantial chromophores (FHD1–FHD6) with a D–π–A framework was designed from a synthesized non-fullerene compound (FH) via structural tailoring with various donor moieties.     

Preparation and characterization of lauric acid–stearic acid/expanded perlite as a composite phase change material

Rapid energy consumption stimulates the development of energy-saving materials. In this work, the L–S eutectic mixture used as a PCM was compounded with EP via vacuum adsorption to synthesize LS/EP CPCM. The maximum mass adsorption rate of EP on L–S is determined to be 70% via leakage experiments. The microscopic morphology, chemical, and crystal structure were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD), respectively. The phase change properties were measured by differential scanning calorimetry (DSC). The melting temperature of LS/EP is 37.79 °C, with a latent heat of 126.05 J g⁻¹, and it has a crystallinity of over 90%. The thermal decomposition was evaluated by TGA. The initial decomposition temperature is 132.20 °C for LS/EP. In addition, the results of accelerated phase change cycling experiments showed that LS/EP CPCM has good reliability.

(1) The maximum mass adsorption rate of EP on L–S is 70%. (2) The melting temperature of LS/EP is 37.79 °C, with latent heat of 126.05 J g⁻¹, and it has a crystallinity of over 90%. (3) LS/EP CPCM has good thermal stability and reliability.     

A simple strategy to prepare a layer-by-layer assembled composite of Ni–Co LDHs on polypyrrole/rGO for a high specific capacitance supercapacitor

A facile and novel electrode material of nickel–cobalt layered double hydroxides (Ni–Co LDHs) layered on polypyrrole/reduced graphene oxide (PPy/rGO) is fabricated for a symmetrical supercapacitor via chemical polymerization, hydrothermal and vacuum filtration. This conscientiously layered composition is free from any binder or surfactants which is highly favorable for supercapacitors. The PPy/rGO serves as an ideal backbone for Ni–Co LDHs to form a free-standing electrode for a high-performance supercapacitor and enhanced the overall structural stability of the film. The well-designed layered nanostructures and high electrochemical activity from the hexagonal-flakes like Ni–Co LDHs provide large electroactive sites for the charge storage process. The specific capacitance (1018 F g⁻¹ at 10 mV s⁻¹) and specific energy (46.5 W h kg⁻¹ at 464.9 W kg⁻¹) obtained for the PPy/rGO|Ni–Co LDHs symmetrical electrode in the current study are the best reported for the two-electrode system for PPy- and LDHs-based composites. The outstanding performance in the prepared LBL film is a result of the LBL architecture of the film and the combined effect of redox reaction and electrical double layer capacitance.

A facile and novel electrode material of nickel–cobalt layered double hydroxides (Ni–Co LDHs) layered on polypyrrole/reduced graphene oxide (PPy/rGO) is fabricated for a symmetrical supercapacitor via chemical polymerization, hydrothermal and vacuum filtration.     

Iodine-mediated C–N and N–N bond formation: a facile one-pot synthetic approach to 1,2,3-triazoles under metal-free and azide-free conditions

A novel strategy towards the synthesis of 1,4-disubstituted 1,2,3-triazoles via C–N and N–N bond formation has been demonstrated under transition metal-free and azide-free conditions. These 1,2,3-triazoles were obtained in a regioselective manner from commercially available anilines, aryl alkenes/aryl alkynes and N-tosylhydrazines using I₂ under O₂ atmosphere. Broad substrate scope, milder reaction conditions, good to moderate yields and clean protocol are the notable features of the method. Moreover, this protocol is amenable for the generation of a library of medicinally important key building blocks.

A novel strategy towards the synthesis of 1,4-disubstituted 1,2,3-triazoles via C–N and N–N bond formation has been demonstrated under transition metal-free and azide-free conditions.     

Synthesis and photoinitiated thiol–ene reactions of exo-mannals – a new route to C-β-d-mannosyl derivatives

Syntheses of acyl protected exo-mannal derivatives were developed starting from O-peracylated mannopyranoses via the corresponding anhydro-aldose tosylhydrazones under modified Bamford–Stevens conditions. The synthesis of analogous O-peralkylated (benzylated and isopropylenated) derivatives was carried out from pyranoid and furanoid mannonolactones using methylene transfer reagents. Photoinitiated thiol–ene additions of these exo-mannals resulted in the corresponding C-(mannopyranosyl/mannofuranosyl)methyl sulfides in medium to good yields with exclusive regio- and β(d) stereoselectivities.

A synthetic procedure was elaborated for O-peracylated exo-mannals. Thiol-ene additions to pyranoid and furanoid exo-mannals gave mannosylmethyl sulfide type adducts with exclusive regio- and β(d)-stereoselectivities including disaccharide mimetics.     

Study on montmorillonite–chlorhexidine acetate–terbinafine hydrochloride intercalation composites as drug release systems

This paper focuses on the intercalation of chlorhexidine acetate (CA) and terbinafine hydrochloride (TBH) into montmorillonite as sustained release drug carriers. The intercalation compounds were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and thermogravimetric analysis (TGA). The basal spacing of montmorillonite increased from 1.23 to 2.97 nm. It was confirmed that CA and TBH molecules were well-stabilized in the interlayer space of clay via mono-, double or triplicate layer stacking. The adsorption amounts and molecular structures of CA and TBH appeared to depend on the cation exchange capacity of MMT, which in turn, tailored the drug release patterns. In vitro release tests of MMT–CA–TBH in 0.9 wt% NaCl solution at 37 °C show a biphasic and sustained profile of CA and TBH ion release. After release, dissolution–diffusion kinetic models were fitted. The mechanism of MMT–CA–TBH release is probably due to surface diffusion and bulk diffusion via ionic exchange of MMT ions on or in the MMT with ions in the NaCl solution. The in vitro release experiments revealed that CA and TBH were released from MMT steadily, depending on the cooperation between the drugs themselves and the electrostatic interactions between the drugs and MMT. It was found that the cross-linking ratio increased due to a decrease in the free volume available for diffusion.

This paper focuses on the intercalation of chlorhexidine acetate (CA) and terbinafine hydrochloride (TBH) into montmorillonite as sustained release drug carriers.