Design and Synthesis of Mixed Halogenated Subphthalocyanines for Lysosome-Targeted Photodynamic Therapy

doi:10.6023/A26040099

Abstract

Photodynamic therapy (PDT) is a promising targeted tumor treatment strategy, and developing high-performance photosensitizers is crucial for its advancement. As excellent macrocyclic photosensitive dyes, subphthalocyanines (SubPcs) show great application potential in tumor PDT. In this study, four low-symmetry SubPc derivatives with gradient fluoro-chloro substitution (SubPc 4~7) were prepared via a one-pot method. Combined with theoretical calculations, the regulatory effects of halogen substitution on their photophysical and antitumor properties were systematically investigated. The results showed that increasing chlorine substitution ratio led to progressive redshifts in both absorption and fluorescence emission wavelengths. Fluorescence quantum yield was negatively correlated with singlet oxygen quantum yield, and the cumulative heavy-atom effect of multiple chlorine atoms effectively promoted intersystem crossing, thereby enhancing photosensitization capability. These derivatives exhibited good optical stability in aqueous environments and could target lysosomes of tumor cells to generate reactive oxygen species. In vitro experiments confirmed that SubPc 4 achieved a tumor cell killing rate of 82%. In vivo mouse models and tissue section analysis further verified its potent antitumor efficacy in PDT. This study provides an important experimental basis for the application of SubPc derivatives in targeted photodynamic antitumor therapy.

Key words: photodynamic therapy, subphthalocyanine, halogen substitution, singlet oxygen, lysosome targeting

Cite this article

Enze Zhang, Jihua Tian, Yinuo Shen, Shaohong Zeng, Yemei Wang, Fenfen Zheng. Design and Synthesis of Mixed Halogenated Subphthalocyanines for Lysosome-Targeted Photodynamic Therapy[J]. Acta Chimica Sinica, 2026, 84(9): 1442-1451.

Export EndNote|Reference Manager|ProCite|BibTeX|RefWorks

share this article

Fig. & Tab. 11

Scheme 1. The synthesis route for compounds SubPcs 4~7

Figure 1. (a) The UV absorption spectra of compounds SubPcs 4~7; (b) The fluorescence emission spectra of compounds SubPcs 4~7

Figure 2. Cyclic voltammograms of compounds SubPc 4 (a), SubPc 5 (b), SubPc 6 (c), and SubPc 7 (d) in dichloromethane

	E_ox/V	E_red/V			E_R^a	H-L (V)^b
	E_ox/V	1st	2nd	3rd	E_R^a	H-L (V)^b
4	1.77	－1.43	－1.60	－2.23	0.17	3.20
5	1.70	－1.40	－1.59	－2.20	0.19	3.10
6	1.70	－1.40	－1.69	－2.20	0.29	3.10
7	1.67	－1.40	－1.56	－2.18	0.16	3.07

Table 1. Half-wave potential (V vs. SCE) of SubPcs 4~7 in CH2Cl2 containing 0.1 mol/L TBAP

Figure 3. MO energy level diagrams of F12-SubPc, Cl12-SubPc and SubPcs 4~7

Figure 4. Fluorescence images of SubPcs 4~7 uptake by 4T1 cells for 4 h, the scale bar is 10 μm

Figure 5. (a) UV absorption spectrum of DPBF at 412 nm using SubPc 4 as photosensitizer; (b) Testing the singlet oxygen generation capability of SubPc 4

		氟原子数	氯原子数	Φ_△/%	Φ_F/%
4	Cl₁₀SubPc	—	10	59.29	17.25
5	Cl₈SubPc	—	8	41.56	19.99
6	F₄Cl₄SubPc	4	4	35.81	28.45
7	F₈Cl₂SubPc	8	2	19.73	32.59

Table 2. F/Cl atom counts and the corresponding singlet-oxygen yield (Φ△) and fluorescence yield (ΦF) of SubPcs 4~7

Figure 6. CLSM images of DCFH staining after 580~590 nm laser irradiation of SubPcs 4~7 in 4T1 cells, the scale bar is 50 μm

Figure 7. (a) In vitro phototoxicity and dark toxicity of SubPc 4 against 4T1 cells evaluated by MTT assay. Cells were incubated with various concentrations of SubPc 4 (2.5, 5.0, 10.0, 20.0, 50.0 μg/mL) for 24 h, followed by irradiation with a 560~580 nm laser (0.5 W/cm2) for 10 min (phototoxicity group) or maintained in the dark (dark toxicity group). Data are presented as mean±SD (n=3). (b) Dose-response curve fitted from the phototoxicity data in (a) and the corresponding half‑maximal inhibitory concentration. (c) Calcein-AM and PI double-staining images of 4T1 cells treated with PBS and SubPc 4 before and after 560~580 nm laser irradiation. The scale bar is 100 µm

Figure 8. Photodynamic therapy efficacy and biosafety evaluation of SubPc 4 in tumor-bearing mice. Groups: PBS＋Laser, SubPc 4 alone, and SubPc 4 ＋Laser. Laser irradiation: 560~580 nm, 0.5 W/cm2, 10 min. (a) Representative photographs of excised tumors; (b) Body weight changes of mice; (c) Statistical comparison of excised tumor weights; (d) Tumor volume growth curves; (e) H&E staining of tumor tissues, The scale bar is 50 µm; (f) H&E staining of heart, liver, spleen, lung, and kidney (Data are shown as mean±SD), The scale bar is 50 µm

References 31

[1]	Cramer G. M.; Cengel K. A.; Busch T. M. Cancer Res. 2022, 82, 534.
[2]	Cai Y.-Y.; Chai T.; Nguyen W.; Liu J.-Y.; Xiao E.-H.; Ran X.; Ran Y.-P.; Du D.; Chen W.; Chen X.-Y. Sig. Transduct. Target. Ther. 2025, 10, 115. doi: 10.1038/s41392-025-02140-y
[3]	Raab O. Z. Biol. 1900, 39, 524.
[4]	Lipson R. L.; Baldes E. J. Arch. Dermatol. 1960, 82, 508. doi: 10.1001/archderm.1960.01580040026005
[5]	Mei J.; Hong Y.-N.; Lam J. W. Y.; Qin A.-J.; Tang Y.-H.; Tang B.-Z. Adv. Mater. 2014, 26, 5429. doi: 10.1002/adma.v26.31
[6]	Yu Q.-S.; Qi C.; Gu S.-X.; Yang X.-D.; Jiang Q.; Wei R.-B.; Shi P.-F. Acta Chim. Sinica 2025, 83, 579 (in Chinese). doi: 10.6023/A24120380
	(于千水, 戚聪, 顾顺心, 杨欣达, 姜琴, 魏荣斌, 施鹏飞, 化学学报, 2025, 83, 579.) doi: 10.6023/A24120380
[7]	Li J.-Q.; Huang Y.-Q.; Ding G.-D.; Zhang R.; Liu X.-F.; Fan Q.-L.; Huang W. Acta Chim. Sinica 2025, 83, 1324 (in Chinese). doi: 10.6023/A25050141
	(李佳启, 黄艳琴, 丁桂第, 张瑞, 刘兴奋, 范曲立, 黄维, 化学学报, 2025, 83, 1324.) doi: 10.6023/A25050141
[8]	Zhang Y.-Q.; Zhan C.; Gong Y.; Lu F.; Fan Q.-L. Acta. Chim. Sinica. 2024, 82, 1226 (in Chinese). doi: 10.6023/A24090286
	(张雨琦, 占辰, 贡祎, 陆峰, 范曲立, 化学学报, 2024, 82, 1226.) doi: 10.6023/A24090286
[9]	Huang Y.-Q.; Luo J.-W.; Li J.-Q.; Zhang R.; Liu X.-F.; Fan Q.-L.; Huang W. Acta Chim. Sinica 2024, 82, 1 (in Chinese). doi: 10.6023/A23100472
	(黄艳琴, 罗集文, 李佳启, 张瑞, 刘兴奋, 范曲立, 黄维, 化学学报, 2024, 82, 1.)
[10]	Li Y.; Wang W.; Zhang Y.-T.; Xiao S.-Z.; Lan H.-C.; Geng P. Acta Chim. Sinica 2024, 82, 443 (in Chinese). doi: 10.6023/A24010035
	(李燕, 王玮, 张毓婷, 肖述章, 兰海闯, 耿鹏, 化学学报, 2024, 82, 443.) doi: 10.6023/A24010035
[11]	Zhang S.-H.; Yang N.-L.; Zhao H.-T.; Sun S.-M.; Chen P.-D.; Cheng C.-W.; Wang C.-J.; He W.-W.; Zhang L.-F.; Cheng L.; Cheng Z.-P. Adv. Funct. Mater. 2026, 36, e13920.
[12]	Ritz J. M.; Khakimzhan A.; Dalluge J. J.; Noireaux V.; Puchner E. M. J. Am. Chem. Soc. 2025, 147, 7588. doi: 10.1021/jacs.4c16907
[13]	Niu P.-Y.; Dai J.-L.; Wang Z.-Y.; Wang Y.-Y.; Feng D.-X.; Li Y.-Y.; Miao W.-J. Pharmaceuticals 2022, 15, 156. doi: 10.3390/ph15020156
[14]	Wang L.-C.; Mei A.-Q.; Li N.; Ruan X.-H.; Sun X.; Cai Y.; Shao J.-J.; Dong X.-C. Chinese Chem. Lett. 2024, 35, 108974. doi: 10.1016/j.cclet.2023.108974
[15]	Labella J.; Torres T. Trends Chem. 2023, 5, 353. doi: 10.1016/j.trechm.2023.02.003
[16]	Lavarda G.; Labella J.; Martínez-Díaz M. V.; Rodríguez-Morgade M. S.; Osuka A.; Torres T. Chem. Soc. Rev. 2022, 51, 9482. doi: 10.1039/d2cs00280a pmid: 36354343
[17]	Demuth J.; Gallego L.; Kozlikova M.; Machacek M.; Kucera R.; Torres T.; Martinez-Diaz M. V.; Novakova V. J. Med. Chem. 2021, 64, 17436. doi: 10.1021/acs.jmedchem.1c01584 pmid: 34813305
[18]	Garcia-Calvo J.; Chen X.-X.; Sakai N.; Matile S.; Torres T. Phys. Chem. Chem. Phys. 2024, 26, 4759. doi: 10.1039/D3CP05476D
[19]	Casellas N. M.; Dai G.-L.; Xue E. Y.; Fonseca A.; Ng D. K. P.; Garcia-Iglesias M.; Torres T. Chem. Commun. 2022, 58, 669. doi: 10.1039/D1CC05977G
[20]	Bodedla G. B.; Ke S.-Y.; Cao Y.-B.; Zhang L.-J.; Wong W.-Y. J. Mater. Chem. C 2026, 14, 119. doi: 10.1039/D5TC03743C
[21]	Gotfredsen H.; Thiel D.; Greissel P. M.; Chen L.; Krug M.; Papadopoulos I.; Ferguson M. J.; Nielsen M. B.; Torres T.; Clark T.; Guldi D. M.; Tykwinski R. R., J. Am. Chem. Soc. 2023, 145, 9548. doi: 10.1021/jacs.2c13353
[22]	Chan J. Y. M.; Kawata T.; Kobayashi N.; Ng D. K. P. Angew. Chem. Int. Ed. 2019, 58, 2272. doi: 10.1002/anie.v58.8
[23]	Skvortsov I. A.; Nikitin I. A.; Lazovskiy D. A.; Stuzhin P. A. Dyes Pigm. 2022, 202, 110282. doi: 10.1016/j.dyepig.2022.110282
[24]	Skvortsov I. A.; Chufarin A. E.; Zaitsev M. V.; Kirakosyan G. A.; Stuzhin P. A. Asian J. Org. Chem. 2023, 12, e202300425.
[25]	Kovkova U. P.; Skvortsov I. A.; Khodov I. A.; Efimov S. V.; Zhabanov Y. A.; Somov N. V.; Liang X.; Pakhomov G. L.; Stuzhin P. A. J. Porphyrins Phthalocyanines 2023, 27, 600. doi: 10.1142/S1088424623500542
[26]	Zhou S.-T.; Lv X.-J.; Li M.-H.; Gao Z.-J.; Tu S.-N.; Qiao S.-S.; Mo M.-J.; Tang X.; Wang Y.-M.; Sun S.-S. Molecules 2023, 28, 725. doi: 10.3390/molecules28020725
[27]	Labella J.; Momblona C.; Klipfel N.; Kanda H.; Kinge S.; Nazeeruddin M. K.; Torres T. J. Mater. Chem. C 2021, 9, 16298. doi: 10.1039/D1TC02600C
[28]	Tejerina L.; Labella J.; Martínez‑Fernández L.; Corral I.; Martínez‑Díaz M. V.; Torres T. Chem. Eur. J. 2021, 27, e202101991.
[29]	Tejerina L.; Martinez-Diaz M. V.; Torres T. Org. Lett. 2019, 21, 3275.
[30]	Arabei S. M.; Pershukevich P. P.; Belkov M. V.; Gladkov L. L.; Tabolich A. A.; Solovyov K. N.; Skvortsov I. A.; Stuzhin P. A. Spectrochim. Acta A 2023, 303, 123254.
[31]	Necedova M.; Magdolen P.; Fülöpova A.; Cigan M.; Zahradník P.; Filo J. Dyes Pigm. 2016, 130, 24. doi: 10.1016/j.dyepig.2016.03.001

混合卤代亚酞菁的设计合成及其溶酶体靶向光动力治疗研究