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Plant Science Today (PST)

Research Articles

Early Access

Pectin micro-encapsulation of pretilachlor for smart herbicide delivery through biopolymer guided slow release

DOI
https://doi.org/10.14719/pst.11446
Submitted
25 August 2025
Published
22-12-2025

Abstract

Conventional pretilachlor formulation faces quick dissipation, leaching, and reduced efficacy. The present study aimed to synthesize encapsulated pretilachlor using pectin to achieve sustained release by optimising counter-ion solution and herbicide concentration. Pretilachlor was microencapsulated with 6 % pectin via ionotropic gelation using 2 % calcium chloride (CaCl2), barium chloride (BaCl2), zinc sulphate (ZnSO4) and zinc acetate as cross-linking baths. Herbicide concentrations of 0.5, 1.0 and 2.0 mL were evaluated. Morphological and encapsulation properties were characterized through phase contrast microscope, field emission scanning electron microscope (FESEM), Fourier transformed infra-red (FTIR) spectroscopy and EDS. Encapsulation efficiency and release profiles were determined via UV-Vis spectrophotometry and analysed using mathematical kinetic models. The extrusion of 6 % pectin solution into 2 % cross-linking baths produced beads of varying shapes, with BaCl2 yielding the most uniform and stable spherical microspheres. The mean diameter of the beads increased from 1.25 to 1.71 mm as pretilachlor concentration increased from 0.5 to 2.0 mL. Encapsulation efficiency and swelling percentage were highest at 0.5 mL concentration (69.4 % and 66.7 %), followed by 1.0 mL (64.04 % and 61.4 %) and 2.0 mL (59.36 % and 61.8 %), respectively. Structural analyses confirmed uniform encapsulation and stable microsphere formation and the encapsulated formulations exhibited a slow and sustained release pattern governed by first-order diffusion-controlled kinetics, in contrast to the rapid initial burst observed in the commercial formulation. Overall, encapsulating 0.5 mL of pretilachlor in 6 % pectin emerged as the most suitable treatment, offering improved encapsulation efficiency, higher swelling capacity and steady herbicide release for effective application.

References

  1. 1. Hasanuzzaman M, Mohsin SM, Bhuyan MB, Bhuiyan TF, Anee TI, Masud AAC, et al. Phytotoxicity, environmental and health hazards of herbicides: challenges and ways forward. In: Prasad MNV, editor. Agrochemicals detection, treatment and remediation. Elsevier; 2020. p. 55–99. https://doi.org/10.1016/B978-0-08-103017-2.00003-9
  2. 2. Brar AS. Environmental and health impacts of herbicide overuse: a review. Journal of Agric Sustain. 2020;15(3):112–30.
  3. 3. Maheswari ST, Ramesh K. Herbicide persistence in soil and water: ecological consequences. Environ Pollut Res. 2018;25(4):321–35.
  4. 4. Ofosu R, Agyemang ED, Márton A, Pásztor G, Taller J, Kazinczi G. Herbicide resistance: managing weeds in a changing world. Agronomy. 2023;13(6):1595. https://doi.org/10.3390/agronomy13061595
  5. 5. Mitra B, Patra K, Bhattacharya PM, Ghosh A, Chowdhury AK, Dhar T, et al. Efficacy of pre- and post-emergence herbicide combinations on weed control in no-till mechanically transplanted rice. Cogent Food Agric. 2022;8(1):2139794. https://doi.org/10.1080/23311932.2022.2139794
  6. 6. Sairamesh K, Rao A, Subbaiah G, Rani PP. Bio-efficacy of sequential application of herbicides on weed control, growth and yield of wet seeded rice. J Weed Sci. 2015;47:201–12.
  7. 7. Campos EV, Ratko J, Bidyarani N, Takeshita V, Fraceto LF. Nature based herbicides and micro-/nanotechnology fostering sustainable agriculture. ACS Sustain Chem Eng. 2023;11(27):9900–17. https://doi.org/10.1021/acssuschemeng.3c02282
  8. 8. Seng CT. Inhibition of pre-emergent herbicide on weedy rice under flooded and saturated soil conditions in rice. Sains Malays. 2024;53(7):1525–32. https://doi.org/10.17576/jsm-2024-5307-04
  9. 9. RajaRajeswari R, Sathiyanarayanan S, Ramesh A, Ayyappan S. Evaluation of bioavailability of residues of pretilachlor in soil and water under paddy cropping condition and their influence onLemna gibba. J Agric Environ. 2013;14:102–10. https://doi.org/10.3126/aej.v14i0.19790
  10. 10. Chaudhary A, Venkatramanan V, Kumar Mishra A, Sharma S. Agronomic and environmental determinants of direct seeded rice in South Asia. Circ Econ Sustain. 2023;3(1):253–90. https://doi.org/10.1007/s43615-022-00173-x
  11. 11. Chen G, Liu Q, Zhang Y, Li J, Dong L. Comparison of weed seedbanks in different rice planting systems. Agron J. 2017;109(2):620–8. https://doi.org/10.2134/agronj2016.06.0348
  12. 12. Rathika S, Ramesh T, Shanmugapriya P. Weed management in direct seeded rice: a review. Int J Chem Stud. 2020;8(4):925–33. https://doi.org/10.22271/chemi.2020.v8.i4f.9723
  13. 13. Kaur P, Kaur P, Bhullar M. Persistence behaviour of pretilachlor in puddled paddy fields under subtropical humid climate. Environ Monit Assess. 2015;187(8):524. https://doi.org/10.1007/s10661-015-4756-3
  14. 14. Busi R. Resistance to herbicides inhibiting the biosynthesis of very long-chain fatty acids. Pest Manag Sci. 2014;70(9):1378–84. https://doi.org/10.1002/ps.3746
  15. 15. Hashim M, Singh V, Singh K, Dhar S, Pandey U. Weed management strategies in direct seeded rice: a review. Agric Rev. 2024;45(2):258–65. https://doi.org/10.18805/ag.R-2245
  16. 16. Chen H, Liu X, Deng S, Wang H, Ou X, Huang L, et al. Pretilachlor releasable polyurea microcapsules suspension optimization and its paddy field weeding investigation. Front Chem. 2020;8:826. https://doi.org/10.3389/fchem.2020.00826
  17. 17. Kumar N, Kumar R, Shakil N, Das T. Nanoformulations of pretilachlor herbicide: preparation, characterization and activity. J Sci Ind Res. 2016;75:676–80.
  18. 18. Sowmiya S, Hemalatha M, Joseph M. Assessment of encapsulated herbicide for sustained release, weed control and crop productivity as a tool for agroecosystem biosafety. Plant Sci Today. 2024;11:5681. https://doi.org/10.14719/pst.5681
  19. 19. Juneja R, Kaur M. Overview on pectin and its pharmaceutical uses. Int J Innov Res Eng Manag. 2022;1:353–6. https://doi.org/10.55524/ijirem.2022.9.1.72
  20. 20. Yadav P, Pandey P, Parashar S. Pectin as natural polymer: an overview. Res J Pharm Technol. 2017;10(4):1225–9. https://doi.org/10.5958/0974-360X.2017.00219.0
  21. 21. Pavithran P, Marimuthu S, R Chinnamuthu C, Lakshmanan A, Bharathi C, Kadhiravan S. Synthesis and characterization of pectin beads for the smart delivery of agrochemicals. Int J Plant Soil Sci. 2021;33(22):136–55. https://doi.org/10.9734/ijpss/2021/v33i2230691
  22. 22. Higuchi T. Mechanism of sustained-action medication. Theoretical analysis of rate of release of solid drugs dispersed in solid matrices. J Pharm Sci. 1963;52(12):1145–9. https://doi.org/10.1002/jps.2600521210
  23. 23. Korsmeyer RW, Gurny R, Doelker E, Buri P, Peppas NA. Mechanisms of solute release from porous hydrophilic polymers. Int J Pharm. 1983;15(1):25–35. https://doi.org/10.1016/0378-5173(83)90064-9
  24. 24. Dash S. Kinetic modeling on drug release from controlled drug delivery systems. Acta Pol Pharm. 2010;67(3):217–23.
  25. 25. Paarakh MP, Jose PA, Setty CM, Peterchristoper G. Release kinetics - concepts and applications. Int J Pharm Res Technol. 2018;8(1):12–20.
  26. 26. Lee BB, Chan ES. Calcium pectinate beads formation: shape and size analysis. J Eng Technol Sci. 2014;46(1):78-92. https://doi.org/10.5614/j.eng.technol.sci.2014.46.1.5
  27. 27. Kumar S, Bhanjana G, Sharma A, Dilbaghi N, Sidhu M, Kim KH. Development of nanoformulation approaches for the control of weeds. Sci Total Environ. 2017;586:1272–8. https://doi.org/10.1016/j.scitotenv.2017.02.138
  28. 28. Vijayamma R, Maria HJ, Thomas S, Shishatskaya EI, Kiselev EG, Nemtsev IV, et al. A study of the properties and efficacy of microparticles based on P(3HB) and P(3HB/3HV) loaded with herbicides. J Appl Polym Sci. 2022;139(10):51756. https://doi.org/10.1002/app.51756
  29. 29. Mummasani A, Marimuthu S, Balachandar D, Radhamani S, Bharathi C, Gowtham G, et al. Microencapsulation and characterization of diclosulam in xanthan gum-based polymeric system for smart delivery of herbicide in crop production. Int J Environ Clim Change. 2022;12(11):1811–24. https://doi.org/10.9734/ijecc/2022/v12i1131167
  30. 30. Maiti S, Dey P, Banik A, Sa B, Ray S, Kaity S. Tailoring of locust bean gum and development of hydrogel beads for controlled oral delivery of glipizide. Drug Deliv. 2010;17(5):288–300. https://doi.org/10.3109/10717541003706265
  31. 31. Grayson ACR, Cima MJ, Langer R. Molecular release from a polymeric microreservoir device: influence of chemistry, polymer swelling and loading on device performance. J Biomed Mater Res A. 2004;69(3):502–12. https://doi.org/10.1002/jbm.a.30019
  32. 32. Issa R, Akelah A, Rehab A, Solaro R, Chiellini E. Controlled release of herbicides bound to poly[oligo(oxyethylene) methacrylate] hydrogels. J Control Release. 1990;13(1):1–10. https://doi.org/10.1016/0168-3659(90)90069-6
  33. 33. Forni F, Vandelli MA, Cameroni R. Influence of drug loading level on drug release and dynamic swelling of crosslinked gelatin microspheres. J Microencapsul. 1992;9(1):29–39. https://doi.org/10.3109/02652049209021220
  34. 34. Liao R, Ren S, Yang P. Quantitative fractal evaluation of herbicide effects on the water-absorbing capacity of superabsorbent polymers. J Nanomater. 2014;2014:905630.
  35. 35. Yun P, Devahastin S, Chiewchan N. Microstructures of encapsulates and their relations with encapsulation efficiency and controlled release of bioactive constituents: a review. Compr Rev Food Sci Food Saf. 2021;20(2):1768-99. https://doi.org/10.1111/1541-4337.12701
  36. 36. Kumar S, Nehra M, Dilbaghi N, Marrazza G, Hassan AA, Kim K. Nano based smart pesticide formulations: emerging opportunities for agriculture. J Control Release. 2019;294:131–53. https://doi.org/10.1016/j.jconrel.2018.12.012
  37. 37. Deepika R, Girigoswami K, Murugesan R, Girigoswami A. Influence of divalent cation on morphology and drug delivery efficiency of mixed polymer nanoparticles. Curr Drug Deliv. 2017;15(5):652–7. https://doi.org/10.2174/1567201814666170825160617
  38. 38. Chang M, Stride E, Edirisinghe M. Nano-organized shells and their application in controlled release. Ther Deliv. 2011;2(10):1247–57. https://doi.org/10.4155/tde.11.94
  39. 39. Boothroyd CB, Moreno MS, Duchamp M, Kovács A, Monge N, Morales GM, et al. Atomic resolution imaging and spectroscopy of barium atoms and functional groups on graphene oxide. Ultramicroscopy. 2014;145:66–73. https://doi.org/10.1016/j.ultramic.2014.03.004
  40. 40. Jejurikar A, Lawrie GA, Martin DJ, Grøndahl L. A novel strategy for preparing mechanically robust ionically cross-linked alginate hydrogels. Biomed Mater. 2011;6:025010. https://doi.org/10.1088/1748-6041/6/2/025010
  41. 41. Rosales TK, Fabi JP. Pectin-based nanoencapsulation strategy to improve the bioavailability of bioactive compounds. Int J Biol Macromol. 2022;229:11–21. https://doi.org/10.1016/j.ijbiomac.2022.12.292
  42. 42. Evy Alice Abigail M. Biochar-based nanocarriers: fabrication, characterization, and application as 2,4-dichlorophenoxyacetic acid nanoformulation for sustained release. 3 Biotech. 2019;9:317. https://doi.org/10.1007/s13205-019-1829-y
  43. 43. Kyomugasho C, Christiaens S, Shpigelman A, Van Loey AM, Hendrickx ME. FT-IR spectroscopy, a reliable method for routine analysis of the degree of methyl esterification of pectin in different fruit- and vegetable-based matrices. Food Chem. 2015;176:82–90. https://doi.org/10.1016/j.foodchem.2014.12.033
  44. 44. Filippov M, Shkolenko GA, Kohn R. Determination of the esterification degree of the pectin of different origin and composition by the method of infrared spectroscopy. Chemicke Zvesti. 1978;32 (2):218-22.
  45. 45. Rodsamran P, Sothornvit R. Microwave heating extraction of pectin from lime peel: characterization and properties compared with the conventional heating method. Food Chem. 2019;278:364–72. https://doi.org/10.1016/j.foodchem.2018.11.067
  46. 46. Cabaniss SE, McVey IF. Aqueous infrared carboxylate absorbances: aliphatic monocarboxylates. Spectrochim Acta A Mol Biomol Spectrosc. 1995;51(13):2385–95. https://doi.org/10.1016/0584-8539(95)01479-9
  47. 47. Mitra S, Werling KA, Berquist EJ, Lambrecht DS, Garrett-Roe S. CH mode mixing determines the band shape of the carboxylate symmetric stretch in Apo-EDTA, Ca²+-EDTA, and Mg²+-EDTA. J Phys Chem A. 2021;125(22):4867-81. https://doi.org/10.1021/acs.jpca.1c03061
  48. 48. Canteri MH, Renard CM, Le Bourvellec C, Bureau S. ATR-FTIR spectroscopy to determine cell wall composition: application on a large diversity of fruits and vegetables. Carbohydr Polym. 2019;212:186–96. https://doi.org/10.1016/j.carbpol.2019.02.021
  49. 49. Hansen PE, Vakili M, Kamounah FS, Spanget-Larsen J. NH stretching frequencies of intramolecularly hydrogen-bonded systems: an experimental and theoretical study. Molecules. 2021;26(24):7651. https://doi.org/10.3390/molecules26247651
  50. 50. Smith B. The big review IV: hydrocarbons. Spectroscopy. 2025;40(1):16-9. https://doi.org/10.56530/spectroscopy.vt7783b7
  51. 51. Instanano. FTIR functional group search [Internet]. Instanano; 2025 [cited 2025 Apr 2]. Available from: https://instanano.com/all/characterization/ftir/ftir-functional-group-search/
  52. 52. Chen XiaoTing CX, Wang TongXin WT. Preparation and characterization of atrazine-loaded biodegradable PLGA nanospheres. J Integr Agric. 2019;18(5):1035–41. https://doi.org/10.1016/S2095-3119(19)62613-4
  53. 53. Sahoo S, Manjaiah K, Datta S, Ahmed Shabeer T, Kumar J. Kinetics of metribuzin release from bentonite-polymer composites in water. J Environ Sci Health B. 2014;49(8):591–600. https://doi.org/10.1080/03601234.2014.911578
  54. 54. Belmokhtar FZ, Elbahri Z, Elbahri M. Preparation and optimization of agrochemical 2,4-D controlled release microparticles using designs of experiments. J Mex Chem Soc. 2018;62(1). https://doi.org/10.29356/jmcs.v62i1.579
  55. 55. Grillo R, Rosa A, Fraceto L. Poly(ε-caprolactone) nanocapsules carrying the herbicide atrazine: effect of chitosan-coating agent on physicochemical stability and herbicide release profile. Int J Environ Sci Technol. 2014;11(6):1691–700.
  56. 56. Sopeña F, Cabrera A, Maqueda C, Morillo E. Controlled release of the herbicide norflurazon into water from ethylcellulose formulations. J Agric Food Chem. 2005;53(9):3540–7. https://doi.org/10.1021/jf048007d
  57. 57. Stloukal P, Kucharczyk P, Sedlarik V, Bazant P, Koutny M. Low molecular weight poly(lactic acid) microparticles for controlled release of the herbicide metazachlor: preparation, morphology and release kinetics. J Agric Food Chem. 2012;60(16):4111–9.

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