Covalent organic frameworks (COFs), synthesized from organic monomers, are porous crystalline polymers. Monomers get attached through strong covalent bonds to form 2D and 3D structures. The adjustable pore size, high stability (chemical and thermal), and metal-free nature of COFs make their applications wider. This review article briefly elaborates the synthesis, types, and applications (catalysis, environmental Remediation, sensors) of COFs. Furthermore, the applications of COFs as biomaterials are comprehensively discussed. There are several reported COFs having good results in anti-cancer and anti-bacterial treatments. At the end, some newly reported COFs having anti-viral and wound healing properties are also discussed.

The pH-sensitive polymeric matrix of basil seed gum (BSG), with two different monomers, such as acrylic acid (AA) and N, N-Methylene-bis-acrylamide (MBA), was selected to use in hydrogels preparation through a free radical copolymerization technique using potassium per sulfate (KPS) as a cross linker. BSG, AA and MBA were used in multiple ratios to investigate the polymer, monomer and initiator effects on swelling properties and release pattern of captopril. Characterization of formulated hydrogels was done by FTIR, DSC/TGA, XRD and SEM techniques to confirm the stability. The hydrogels were subjected to a variety of tests, including dynamic swelling investigations, drug loading, in vitro drug release, sol–gel analyses and rheological studies. FTIR analysis confirmed that after the polymeric reaction of BSG with the AA monomer, AA chains grafted onto the backbone of BSG. The SEM micrographs illustrated an irregular, rough, and porous form of surface. Gel content was increased by increasing the contents of polymeric gum (BSG) with monomers (AA and MBA). Acidic and basic pH effects highlighted the difference between the swelling properties with BSG and AA on increasing concentration. Kinetic modelling suggested that Korsmeyer Peppas model release pattern was followed by the drug with the non-Fickian diffusion mechanism.

The current study reports the fabrication of co-combination gel using Pregabalin and Withania coagulans fruit extract to validate its effectiveness for neuropathic pain in chronic constriction injury (CCI) rat models. Three topical gels were prepared using Carbopol 934 through a pseudo-ternary phase diagram incorporating the Pregabalin (2.5%), Withania coagulans extract (2%), and co-combination of both Pregabalin (2.5%) and Withania coagulans extract (2%). Gels were characterized. FTIR showed a successful polymeric network of the gel without any interaction. The drug distribution at the molecular level was confirmed by XRD. The AFM images topographically indicated the rough surface of gels with a size range from 0.25 to 330 nm. DSC showed the disappearance of sharp peaks of the drug and extract, showing successful incorporation into the polymeric network of gels. The in vitro drug release of co-combination gel was 73% over 48 h. The mechanism of drug release by combination gel was Higuchi+ fickian with values of n (0.282) and R² (0.947). An in vivo study for pain assessment via four methods: (i) heat hyperalgesia, (ii) cold allodynia, (iii) mechano-hyperalgesia, and (iv) dynamic mechano-allodynia, confirmed that topical treatment with co-combination gel reduced the pain significantly as indicated by the p value: R1 (p < 0.001), R2 (p < 0.001), R3 (p < 0.015), and R4 (p < 0.0344). The significance order was R2 (****) > R1 (***) > R3 (**) > R4 (*) > R5 (ns).

The rapid progression in biomaterial nanotechnology apprehends the potential of non-toxic and potent polysaccharide delivery modules to overcome oral chemotherapeutic challenges. The present study is aimed to design, fabricate and characterize polysaccharide nanoparticles for methotrexate (MTX) delivery. The nanoparticles (NPs) were prepared by Abelmoschus esculentus mucilage (AEM) and chitosan (CS) by the modified coacervation method, followed by ultra-sonification. The NPs showed much better pharmaceutical properties with a spherical shape and smooth surface of 213.4–254.2 nm with PDI ranging between 0.279–0.485 size with entrapment efficiency varying from 42.08 ± 1.2 to 72.23 ± 2.0. The results revealed NPs to possess positive zeta potential and a low polydispersity index (PDI). The in-vitro drug release showed a sustained release of the drug up to 32 h with pH-dependence. Blank AEM -CS NPs showed no in-vivo toxicity for a time duration of 14 days, accompanied by high cytotoxic effects of optimized MTX loaded NPs against MCF-7 and MD-MBA231 cells by MTT assay. In conclusion, the findings advocated the therapeutic potential of AEM/CS NPs as an efficacious tool, offering a new perspective for pH-responsive routing of anticancer drugs with tumor cells as a target.

Mimosa pudica seed mucilage (MPM) is composed of glucuronoxylan, which is a swellable, pH-responsive and non-toxic biomaterial. Herein, we aimed to extract MPM from M. pudica seeds (MP seeds) to ascertain optimization of extraction conditions to get highest yield by response surface methodology, via Box-Behnken design (RSM-BBD). MPM was extracted from MP seeds by a hot water extraction method. The effects of four different parameters on the extraction yield of MPM were evaluated: pH of the extraction medium (1–10), seed/water contact time (1–12 h), the temperature of extraction medium (30–90 °C), and seed/water ratio (1:5–1:35 w/v). The maximum yield of MPM obtained by Design-Expert software was 10.66% (10.66 g/100 g) at pH 7, seed/water contact time of 6 h, extraction temperature of 50 °C, and seed/water ratio of 1:20 w/v. The p values of ANOVA were found to be less than 0.0001, which indicated that the extraction yield of MPM was significantly affected by all the study parameters. The results revealed that pH and extraction temperature were the most significant factors affecting the yield of MPM. MPM in compressed tablet form showed pH-responsive on–off switching behavior at pH 7.4 and 1.2 in a reversible manner. MPM in compressed tablet form sustained the release of itopride for 16 h following a super case-II transport mechanism and zero-order release kinetics.

Combinations of polymers can improve the functional properties of microspheres to achieve desired therapeutic goals. Hence, the present study aimed to formulate Prunus armeniaca gum (PAG) and sodium alginate microsphere for sustained drug release. Blended and coated microspheres were prepared using the ionotropic gelation technique. The effect of polymer concentration variation was studied on the structural and functional properties of formulated microspheres. FTIR, XRD, and thermal analysis were performed to characterize the microspheres. All the formulations were well-formed spherical beads having an average diameter from 579.23 ± 07.09 to 657.67 ± 08.74 μm. Microspheres entrapped drugs within the range 65.86 ± 0.26–83.74 ± 0.79%. The pH-dependent swelling index of coated formulations was higher than blended. FTIR spectra confirmed the presence of characteristic peaks of entrapped Tramadol hydrochloride showing no drug-polymer interaction. In vitro drug release profile showed sustained release following the Korsmeyer-Peppas kinetic model with an R² value of 0.9803–0.9966. An acute toxicology study employing the oral route in Swiss albino mice showed no signs of toxicity. It can be inferred from these results that blending PAG with sodium alginate can enhance the stability of alginate microspheres and improve its drug release profile by prolonging the release time.