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S. Prakash,
N. Haridharan,
- Research Scholar, Department of Chemistry, Vel Tech Rangarajan Dr. Sagunthala R&D Institute of Science and Technology, Avadi, Chennai, Tamil Nadu, India
- Professor, Department of Chemistry, Vel Tech Rangarajan Dr. Sagunthala R&D Institute of Science and Technology, Avadi, Chennai, Tamil Nadu, India
Abstract
Amphiphilic block copolymers have attracted considerable interest in pharmaceutical and biomedical applications, including controlled drug release, gene delivery, and biomolecular sensing. In this study, fluorescent amphiphilic block copolymers were designed to facilitate interactions with biological molecules such as DNA and antiviral agents, enabling their behavior to be monitored through fluorescence spectroscopy. Two novel block copolymers, poly(methyl methacrylate) – b – poly(dimethylaminoethyl methacrylate – co – naphthyl methacrylate) [PMMA-b-P(DMAEMA-co-NMA)] and poly(styrene) – b – poly(tert-butyl acrylate – co – naphthyl methacrylate) [PS-b-P(t-BA-co-NMA)], were synthesized successfully via atom transfer radical polymerization (ATRP) using Copper(I) Bromide (CuBr) as catalyst and N,N,N′,N″,N″-pentamethyldiethylenetriamine (PMDETA) as ligand. To establish steroid functionality into the polymer architecture, a steroid-based initiator has been prepared by reacting ergosterol with 2-bromoisobutyryl bromide. Gel permeation chromatography (GPC), proton nuclear magnetic resonance (1H NMR), Fourier-transform infrared (FTIR), and UV–Visible spectroscopy was utilized to characterize the synthesized polymers. The monomer conversion and the increasing in molecular weight were revealed by polymerization kinetics which indicated controlled polymer growth. The fluorescence characteristics of the block copolymers were investigated, and their self-assembly into micellar structures in aqueous media was confirmed. Furthermore, DNA-binding studies demonstrated that the steroid-containing block copolymers exhibited progressive fluorescence quenching with increasing DNA concentration (1–10 µg), suggesting effective polymer–DNA interactions and supporting the formation of self-assembled nanostructures.
Keywords: Living radical polymerization, ATRP, Fluorescent polymers, DNA, Amphiphilic block copolymer, Steroid.
References
[1] L. Dinan and R. Lafont, “Effects and applications of arthropod steroid hormones (ecdysteroids) in mammals,” J Endocrinol, vol. 191, no. 1, pp. 1–8, Jun. 2006, doi: 10.1677/joe.1.06900.
[2] T. Spelsberg, A. Goldberger, J. Hora, M. Horton, and B. Littlefield, “Characterization of the Nuclear Binding Sites (Acceptor Sites) for a Steroid Receptor,” in Gene Regulation by Steroid Hormones III, A. K. Roy and J. H. Clark, Eds., New York, NY: Springer New York, 1987, pp. 111–136. doi: 10.1007/978-1-4612-4686-2_8.
[3] E. K. Galanov, G. K. Kostyuk, M. V. Mukhina, I. D. Kostrov, and R. I. Mel’nik, “Study of phase transformations in various cholesteric liquid crystals,” J Struct Chem, vol. 17, no. 4, pp. 599–603, Jul. 1977, doi: 10.1007/BF00753446.
[4] R. B. Umamaheshwari and N. K. Jain, “Receptor-mediated targeting of lipobeads bearing acetohydroxamic acid for eradication of Helicobacter pylori,” Journal of Controlled Release, vol. 99, no. 1, pp. 27–40, Sep. 2004, doi: 10.1016/j.jconrel.2004.06.006.
[5] G. Satchanska, S. Davidova, and P. D. Petrov, “Natural and Synthetic Polymers for Biomedical and Environmental Applications,” Polymers, vol. 16, no. 8, Apr. 2024, doi: 10.3390/polym16081159.
[6] “Glycosylation: mechanisms, biological functions and clinical implications | Signal Transduction and Targeted Therapy.” Accessed: Jul. 02, 2026. [Online]. Available: https://www.nature.com/articles/s41392-024-01886-1
[7] “Various biological functions of carbohydrate chains learned from glycosyltransferase-deficient mice – PMC.” Accessed: Jul. 02, 2026. [Online]. Available: https://pmc.ncbi.nlm.nih.gov/articles/PMC7445053/
[8] C. L. Reading, “Carbohydrate Structure, Biological Recognition, and Immune Function,” in The Biology of Glycoproteins, R. J. Ivatt, Ed., Boston, MA: Springer US, 1984, pp. 235–321. doi: 10.1007/978-1-4684-7464-0_5.
[9] S. Liu, “The Future of Free Radical Polymerizations,” Chem. Mater., vol. 36, no. 4, pp. 1779–1780, Feb. 2024, doi: 10.1021/acs.chemmater.4c00312.
[10] D. T. Gentekos, R. J. Sifri, and B. P. Fors, “Controlling polymer properties through the shape of the molecular-weight distribution,” Nat Rev Mater, vol. 4, no. 12, pp. 761–774, Dec. 2019, doi: 10.1038/s41578-019-0138-8.
[11] H. R. Lamontagne and B. H. Lessard, “Nitroxide-Mediated Polymerization: A Versatile Tool for the Engineering of Next Generation Materials,” ACS Appl. Polym. Mater., vol. 2, no. 12, pp. 5327–5344, Dec. 2020, doi: 10.1021/acsapm.0c00888.
[12] S. Harrisson, R. Whitfield, A. Anastasaki, and K. Matyjaszewski, “Atom transfer radical polymerization,” Nat Rev Methods Primers, vol. 5, no. 1, p. 2, Jan. 2025, doi: 10.1038/s43586-024-00370-y.
[13] P. Krys and K. Matyjaszewski, “Kinetics of Atom Transfer Radical Polymerization,” European Polymer Journal, vol. 89, pp. 482–523, Apr. 2017, doi: 10.1016/j.eurpolymj.2017.02.034.
[14] S. Kotha, N. K. Gupta, and S. Ansari, “One-pot thiol-free synthetic approach to sulfides, and sulfoxides selectively,” RSC Adv., vol. 12, no. 39, pp. 25154–25162, Sep. 2022, doi: 10.1039/d2ra04872h.
[15] H. Lee, Y. Lee, N. Kim, and M. J. Park, “Polymer chain-end chemistry: Unlocking next-generation functional materials,” Progress in Polymer Science, vol. 168, p. 102003, Sep. 2025, doi: 10.1016/j.progpolymsci.2025.102003.
[16] M. Kamigaito, T. Ando, and M. Sawamoto, “Metal-Catalyzed Living Radical Polymerization,” Chem. Rev., vol. 101, no. 12, pp. 3689–3746, Dec. 2001, doi: 10.1021/cr9901182.
[17] M. Sun, G. Szczepaniak, S. Dadashi-Silab, T.-C. Lin, T. Kowalewski, and K. Matyjaszewski, “Cu-Catalyzed Atom Transfer Radical Polymerization: The Effect of Cocatalysts,” Macromolecular Chemistry and Physics, vol. 224, no. 3, p. 2200347, 2023, doi: 10.1002/macp.202200347.
[18] H. Liu, V. A. Maugein, and D. M. Haddleton, “Radical polymerisation and thiol–ene post-polymerisation functionalisation of terpenoid acrylates in conventional and renewably sourced organic solvents,” Polym. Chem., vol. 15, no. 28, pp. 2862–2872, Jul. 2024, doi: 10.1039/d4py00340c.
[19] X. Luo et al., “Biomass-derived carbon dots for the initiation of conventional radical and ATRP-based photopolymerization processes,” Nat Protoc, vol. 20, no. 12, pp. 3695–3721, Dec. 2025, doi: 10.1038/s41596-025-01210-3.
[20] H. Zhong, B. Zhao, and J. Deng, “Synthesis and Application of Fluorescent Polymer Micro- and Nanoparticles,” Small, vol. 19, no. 26, p. 2300961, 2023, doi: 10.1002/smll.202300961.
[21] S. Wei, Z. Zhang, Y. Xu, D. Dang, and R. Zeng, “Covalent Installation of Fluorophores into Polyethylene: Synthesis, Characterization, and Applications,” Macromolecules, vol. 57, no. 8, pp. 3595–3603, Apr. 2024, doi: 10.1021/acs.macromol.4c00381.
[22] H. Xu, W. Zhang, and M. Wang, “Bioinspired Fluorescent Polymers: Synthesis, Processing, and Applications†,” Chinese Journal of Chemistry, vol. 41, no. 4, pp. 458–468, 2023, doi: 10.1002/cjoc.202200493.
[23] S. Gao et al., “Albumin tailoring fluorescence and photothermal conversion effect of near-infrared-II fluorophore with aggregation-induced emission characteristics,” Nat Commun, vol. 10, no. 1, p. 2206, May 2019, doi: 10.1038/s41467-019-10056-9.
[24] J. Larson et al., “The Use of Dansyl Chloride to Probe Protein Structure and Dynamics,” International Journal of Molecular Sciences, vol. 26, no. 2, Jan. 2025, doi: 10.3390/ijms26020456.
[25] S. Milles et al., “Organization of fluorescent cholesterol analogs in lipid bilayers — Lessons from cyclodextrin extraction,” Biochimica et Biophysica Acta (BBA) – Biomembranes, vol. 1828, no. 8, pp. 1822–1828, Aug. 2013, doi: 10.1016/j.bbamem.2013.04.002.
[26] S. Biswas, P. Rajdev, A. Banerjee, and A. Das, “Mitochondria-targeting nanostructures from enzymatically degradable fluorescent amphiphilic polyesters,” Nanoscale, vol. 17, no. 10, pp. 5732–5742, Mar. 2025, doi: 10.1039/d4nr04696j.
[27] F. Li, J. Tang, J. Geng, D. Luo, and D. Yang, “Polymeric DNA hydrogel: Design, synthesis and applications,” Progress in Polymer Science, vol. 98, p. 101163, Nov. 2019, doi: 10.1016/j.progpolymsci.2019.101163.
[28] A. Krishnan, S. Roy, and S. Menon, “Amphiphilic block copolymers: From synthesis including living polymerization methods to applications in drug delivery,” European Polymer Journal, vol. 172, p. 111224, Jun. 2022, doi: 10.1016/j.eurpolymj.2022.111224.
[29] U. Chatterjee, S. K. Jewrajka, and B. M. Mandal, “The amphiphilic block copolymers of 2-(dimethylamino)ethyl methacrylate and methyl methacrylate: Synthesis by atom transfer radical polymerization and solution properties,” Polymer, vol. 46, no. 24, pp. 10699–10708, Nov. 2005, doi: 10.1016/j.polymer.2005.09.045.
[30] P. V. Ivchenko, “Controlled Polymerization,” Polymers, vol. 15, no. 6, Mar. 2023, doi: 10.3390/polym15061379.
[31] S. Li et al., “Synthesis of PAN with adjustable molecular weight and low polydispersity index (PDI) value via reverse atom transfer radical polymerization,” Designed Monomers and Polymers, vol. 22, pp. 180–186, Oct. 2019, doi: 10.1080/15685551.2019.1678557.
[32] M. Vicevic, K. Novakovic, and K. Boodhoo, “Free-Radical Polymerization of Styrene: Kinetic Study in a Spinning Disc Reactor (SDR),” Front. Chem. Eng., vol. 3, Apr. 2021, doi: 10.3389/fceng.2021.661498.
[33] Z. Li et al., “A controlled synthesis method of alkyl methacrylate block copolymers via living anionic polymerization at ambient temperature,” RSC Adv., vol. 9, no. 28, pp. 16049–16056, May 2019, doi: 10.1039/c9ra01577a.
[34] “Evaluating Polymerization Methods and Deprotection Strategies for Making Water Soluble Poly(acrylic acid) with Hydrolyzable Breaking Points – Däbritz – 2025 – Macromolecular Chemistry and Physics – Wiley Online Library.” Accessed: Jul. 02, 2026. [Online]. Available: https://onlinelibrary.wiley.com/doi/10.1002/macp.202500080?msockid=0b775ca167fc69df0acd4af5669e686c
[35] “Rapid and Quantitative De-tert-butylation for Poly(acrylic acid) Block Copolymers and Influence on Relaxation of Thermoassociated Transient Networks | Macromolecules.” Accessed: Jul. 02, 2026. [Online]. Available: https://pubs.acs.org/doi/10.1021/acs.macromol.8b01440?__cf_chl_f_tk=wFseF4Cbi3qIKpKHPX.ngyTqrhWB5517UhefB8pJpF0-1782970740-1.0.1.1-_C525bU7yShHWsNeHfHFB2WkZZVbeFcSjNL52DOQErk
[36] C. M. Penso, E. M. S. Castanheira, M. C. Paiva, and L. M. Gonçalves, “Polymer Sorting Through Fluorescence Spectra,” Bioengineering, vol. 12, no. 7, Jun. 2025, doi: 10.3390/bioengineering12070708.
[37] G. K. V. Saraiva et al., “Characterization of PMMA-b-PDMAEMA aggregates in aqueous solutions,” Colloid Polym Sci, vol. 297, no. 4, pp. 557–569, Apr. 2019, doi: 10.1007/s00396-019-04482-w.
[38] Y. Liu, Y. Liu, F. Feng, and W. Wang, “Self-Assembly of Block Copolymers to Prepare Advanced Materials with Hierarchical Functional Nanostructures,” Nanomanufacturing, vol. 5, no. 4, Nov. 2025, doi: 10.3390/nanomanufacturing5040018.
[39] “DNA−Block Copolymer Conjugates | Journal of the American Chemical Society.” Accessed: Jul. 02, 2026. [Online]. Available: https://pubs.acs.org/doi/full/10.1021/ja0156845
[40] M. Khan, “Polymers as Efficient Non-Viral Gene Delivery Vectors: The Role of the Chemical and Physical Architecture of Macromolecules,” Polymers, vol. 16, no. 18, Sep. 2024, doi: 10.3390/polym16182629.
[41] J. Lietard, D. Ameur, and M. M. Somoza, “Sequence-dependent quenching of fluorescein fluorescence on single-stranded and double-stranded DNA,” RSC Adv., vol. 12, no. 9, pp. 5629–5637, Feb. 2022, doi: 10.1039/d2ra00534d.
[42] R. Kalinova, P. Videv, S. Petrova, J. Doumanov, and I. Dimitrov, “Poly(2-(dimethylamino)ethyl methacrylate)-Grafted Amphiphilic Block Copolymer Micelles Co-Loaded with Quercetin and DNA,” Molecules, vol. 29, no. 11, May 2024, doi: 10.3390/molecules29112540.

Journal of Polymer & Composites
| Volume | 14 | |
| 05 | ||
| Received | 14/07/2026 | |
| Accepted | 30/07/2026 | |
| Published | 12/08/2026 | |
| Publication Time | 29 Days |