Efficiency Of Singlet Oxygen Research Articles

Artificial Light-Harvesting Systems with a Three-Step Sequential Energy Transfer Mechanism for Efficient Photocatalytic Minisci-Type Late-Stage Functionalization.

The natural process of photosynthesis involves a series of consecutive energy transfers, but achieving more steps of efficient energy transfer and photocatalytic organic conversion in artificial light-harvesting systems (ALHSs) continues to pose a significant challenge. In the present investigation, a range of ALHSs showcasing a sophisticated three-step energy transfer mechanism is designed, which are meticulously crafted using pillar[5]arene (WP[5]) and p-phenylenevinylene derivative (PPTPy), utilizing host-guest interactions as energy donors. Three distinct types of fluorescent dyes, namely Rhodamine B (RhB), Sulforhodamine 101 (SR101), and Cyanine 5 (Cy5), are employed as acceptors of energy. Starting from PPTPy-2WP[5], energy is sequentially transferred to RhB, SR101, and Cy5, successfully constructing a multi-step continuous energy transfer system with high energy transfer efficiency. More interestingly, as energy is progressively transferred, the efficiency of superoxide anion radical (O2 •-) generation gradually increased, while the efficiency of singlet oxygen (1O2) generation decreased, achieving the transformation from type II photosensitizer to type I photosensitizer. Furthermore, in order to fully utilize the energy harvested and reactive oxygen species (ROS) obtained, the ALHSs employ a multi-step sequential energy transfer process to enhance Minisci-type alkylation reactions with aldehydes through photocatalysis for late-stage functionalization in an aqueous environment, achieving a 91% yield.

Rational Design, Synthesis, and Evaluation of Rofecoxib-Based Photosensitizers for the NIR Imaging and Photo-Oxidization of Aβ Aggregates.

The photo-oxidation of amyloid-β (Aβ) protein catalyzed by Aβ-targeting photosensitizers shows high potential in treating Alzheimer's disease (AD). Herein, we report the first example of photosensitizers based on the rofecoxib scaffold, in which rational introduction of the electron-absorbing pyridinium/quinolinium moiety to the skeleton of rofecoxib could not only extend the absorption and emission wavelengths but also increase the efficiency of singlet oxygen (1O2) production. The emission wavelengths of R-S-MP, R-S-MC, and R-S-MQ are red-shifted to 860 nm, which might benefit the NIR imaging of Aβ aggregates with low photoscattering and autofluorescence. In addition, R-S-MP can identify Aβ plaques in brain sections of AD mice and detect abnormal viscosity environments, facilitating the pathological study of Alzheimer's disease. Most importantly, upon complexation with Aβ plaques, R-S-MP and R-S-MC could produce high singlet oxygen (1O2) under light irradiation, which can achieve the specific photo-oxidation of Aβ protein. Our optimized photosensitizers could change the conformation of β-rich Aβ protein and enhance its clearance through the lysosomal pathway, leading to the reduction of the Aβ-mediated neurotoxicity. All these excellent characteristics of our dual-functional photosensitizers for simultaneous imaging and photo-oxidation of Aβ aggregates suggest their promising prospects in pathological research in AD.

PH modulates efficiency of singlet oxygen production by flavin cofactors.

Flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN) are frequently used interchangeably in the catalysis of various reactions as part of flavoenzymes because they have the same functional component, the isoalloxazine ring. However, they differ significantly in their conformational properties. The inclusion of two planar rings in the structure of FAD greatly increases the range of possible conformations compared to FMN. An exemplary instance of this is the remarkable disparity in singlet oxygen efficiency production, Φ Δ, between FMN and FAD. Under neutral pH conditions, FAD has low photosensitizing activity with Φ Δ ∼ 0.07 while FMN demonstrates high photosensitizing activity with Φ Δ ∼ 0.6. Both adenine rings and isoalloxazine in FAD contain pH titratable groups. Through comprehensive analysis of the kinetics of the transient absorbance of the triplet state and the phosphorescence of singlet oxygen from FAD and FMN, we determined the correlation between different conformational states and the pH-dependent generation of singlet oxygen. Based on our findings, we may deduce that within the pH range of pH 2 to pH 13, only two out of the five potential structural states of FAD are capable of efficiently producing singlet oxygen. There are two open conformations: (i) an acidic FAD conformation with a protonated adenine ring, which is around 10 times more populated than the neutral open FAD conformation, and (ii) a neutral pH FAD conformation, which is significantly less populated. The FAD conformer with a protonated adenine ring at acidic pH generates singlet oxygen with approximately 50% efficiency compared to the constantly open FMN at neutral pH. This may have implications for singlet oxygen synthesis in acidic environments.

Near-infrared hemicyanine photosensitizer for targeted mitochondrial viscosity imaging and efficient photodynamic therapy

As a severe threat to human health, cancer has always been one of the most significant challenges facing the medical field. However, there is currently no effective technology or method to diagnose and treat cancer simultaneously. Therefore, developing a new approach that integrates diagnosis and treatment holds promise as a means of achieving personalized and precise cancer therapy. In this study, we developed a novel dual-functional near-infrared mitochondrial-targeted photosensitizer, Hcy-I, which is capable of simultaneously monitoring cellular viscosity and specifically targeting mitochondria for photodynamic therapy. Compared with traditional hemicyanine dyes, the introduction of iodine atoms in Hcy-I enhanced spin–orbit coupling (SOC) and promoted the intersystem crossing (ISC) rate, thereby increasing the efficiency of singlet oxygen (1O2) generation. In vitro experiments demonstrated that Hcy-I exhibited high sensitivity to viscosity variations and efficiently generated 1O2 under 638 nm laser irradiation, with an 1O2 quantum yield of up to 48.9 %. Cell experiments further revealed that this photosensitizer could effectively target mitochondria for photodynamic therapy, disrupting mitochondrial membrane potential and inducing cell death. When treated with Hcy-I at a concentration of 0.8 µM, the survival rate of HepG-2 cells was only 13 %. These results suggested that Hcy-I had the potential to integrate cancer diagnosis and treatment. The research not only promotes the development of photodynamic thereby technology, but also opens up new avenues for the diagnosis and treatment of cancer.

Synthesis of non-peripheral phthalocyanine sensitizers and investigation of the effect of ultrasound-light stimulus synergy on singlet oxygen production

The high singlet oxygen production capacity and other unique properties of phthalocyanines allow these compounds to be widely used as sensitizers in photodynamic therapy (PDT) and sonodynamic therapy (SDT) in the treatment of cancer. Sono-photodynamic therapy (SPDT), which uses a combination of light and sound stimulation together and has a very high therapeutic effect compared to PDT, is an increasingly important new method for cancer treatment. Published studies on the application of non-peripherally phthalocyanines in SPDT are limited in the literature. With this in mind, in this study, the synthesis and characterization of novel non-peripherally tetra-substituted (4-tert-butylbenzyl)oxy) metal-free (2), Mg(II) (3), Zn(II) (4), and In(III)CI (5) phthalocyanines and their potential as a sono-photosensitizer in SPDT applications as well as PDT applications were determined. Comparative photochemical and sono-photochemical studies showed that the singlet oxygen quantum yields of the synthesised phthalocyanine compounds were calculated as 0.027, 0.22, 0.29 and 0.32 for 2, 3, 4 and 5 respectively, by photochemical studies using only light irradiation, while these values increased to 0.11, 0.28, 0.58 and 0.64 for 2, 3, 4 and 5 respectively, by sono-photochemical studies after the synergistic effect of light and ultrasound. These results showed that the combined use of ultrasound waves and light as a stimulation method exhibited a more effective therapeutic effect compared to light stimulation alone. According to the singlet oxygen efficiency, it was shown that the presence of a metal ion on the phthalocyanine ring increased the singlet oxygen production in both methods.

Optimization of quinolinium-carbazole theranostics for the improved photooxidation of β-amyloid aggregates with the variation of conjugation site

Alzheimer’s disease (AD), the most prevalent neurodegenerative condition, is characterized by a gradual decline in cognitive function and memory loss. Presently, it ranks as the fifth leading cause of death worldwide. Photodynamic therapy, with its operational flexibility, noninvasive approach, and high spatial and temporal resolution, has emerged as an innovative therapeutic method, enhancing therapeutic efficacy and minimizing systemic toxicity. In this work, we have designed two donor-π-acceptor (D-π-A) type photosensitizers targeting amyloid, differing in the donor and acceptor junction sites. Surprisingly we found that by altering the junction site of the donor and acceptor from the 2-position to the 3-position of carbazole, the binding affinity and singlet oxygen efficiency of compound 3-QM16 improved compared to compound 2-QM16. This modification facilitated β-amyloid imaging and photooxidative therapy. Our study might shed light on the further optimization of the photooxidation performance of photosensitizers on misfolded proteins.

High Singlet Oxygen Generating Benzothienyl‐[b]‐fused BODIPY Nanoaggregates and Photoinduced Apoptosis in Human Carcinoma

AbstractHeavy atom free organic materials absorbing in red to near infrared (NIR) region are potential candidates as photosensitizers (PS) in photodynamic therapy (PDT). PDT relies on many factors and one of them is singlet oxygen generation ability of PS in aqueous medium. In this contribution, we report the synthesis of a new PS i. e., 8‐thienyl bisbenzothieno‐[b]‐fused‐boron‐dipyrromethene (BT‐[b]‐fused BODIPY). This PS shows absorption (λabs) at ~650 nm in toluene while in its water‐dispersible nanoaggregates it is found at ~764 nm. Nanoaggregates of BT‐[b]‐fused BODIPY demonstrated dual advantages, (i) facilitating PS release in the cellular system and (ii) sharply enhanced singlet oxygen efficiency ( ~48 %) in aqueous medium. Intracellular reactive oxygen species (ROS) generation was confirmed by 2′,7′‐dichlorodihydrofluorescein diacetate (DCFDA) assay in A549 cells. In vitro photocytotoxic studies of BT‐[b]‐fused BODIPY are carried out in different carcinomas i. e., MCF‐7 and A549 cells. It has zero dark cell toxicity while half maximal inhibitory concentration (IC50) in MCF‐7 is found to be low (6.08±1.1) μM and 7.41±1.9 μM in A549 on 15 min light exposure. These nanoaggregates induce apoptosis in cancer cells on light irradiation thereby proving it to be a potential PS for PDT.

FRET‐Amplified Singlet Oxygen Generation by Nanocomposites Comprising Ternary AgInS2/ZnS Quantum Dots and Molecular Photosensitizers

AbstractAntibacterial photodynamic therapy (a‐PDT) has emerged as a promising non‐invasive therapeutic modality that utilizes the combination of a photosensitive agent, molecular oxygen, and excitation light to generate reactive oxygen species (ROS), demonstrating remarkable activity against multidrug‐resistant bacterial infections. However, the effective use of conventional photosensitizers is significantly limited by a number of their shortcomings, namely, poor water solubility and low selectivity. Herein, we present a novel biocompatible water‐soluble nanocomposite based on hydrophobic tetraphenylporphyrin (TPP) molecules and hydrophilic ternary AgInS2/ZnS quantum dots incorporated into a chitosan matrix as an improved photosensitizer for a‐PDT. We demonstrated that TPP molecules could be successfully transferred into chitosan solution while remaining primarily in the form of monomers, which are capable of singlet oxygen generation. We performed a detailed analysis of the Förster resonance energy transfer (FRET) between quantum dots and TPP molecules within the nanocomposite and proposed the mechanism of the singlet oxygen efficiency enhancement via FRET.

Fluorescent protein chromophores modified with aromatic heterocycles for photodynamic therapy and two-photon fluorescence imaging.

In this paper, three fluorescent protein chromophore analogs PFPAr (PFPP, PFPC, and PFPT) were synthesized and proved to be useful for photodynamic therapy and two-photon fluorescence imaging. By adding five- or six-membered aromatic heterocycles to the photosensitizer PFP, we obtained three fluorescent protein photosensitizers PFPAr with better performances. As a demonstration, compared with the reported photosensitizer PFP, photosensitizer PFPP exhibits larger emission wavelengths (701 nm) and achieves a slight enhancement in the efficiency of singlet oxygen (ΦΔ = 23%). Notably, PFPP can perform good two-photon fluorescence imaging with an 800 nm femtosecond laser in zebrafish. In in vitro cytotoxicity assays, PFPP shows good phototoxicity (IC50 = 4.12 μM) and acceptable dark toxicity (cell viability assay >90%). The reactive oxygen imaging experiments and AO/EB double staining assay indicate that PFPP can generate singlet oxygen to eliminate A-549 tumor cells effectively with photoexcitation of 460 nm blue light (20 mW cm-2). Furthermore, PFPP can label the lysosomes of tumor cells with high specificity for lysosomes (Pearson's correlation coefficient of 0.91). Thus, our study demonstrated that the rational introduction of aromatic heterocycles into fluorescent protein photosensitizers can effectively enhance the key parameters of photosensitivity and pave the way for further two-photon photodynamic therapy.

Photodynamic Eradication of Pseudomonas aeruginosa with Ru-Photosensitizers Encapsulated in Enzyme Degradable Nanocarriers.

The development of new approaches for the treatment of the increasingly antibiotic-resistant pathogen Pseudomonas aeruginosa was targeted by enhancing the effect of local antimicrobial photodynamic therapy (aPDT) using poly(ethylene glycol)-block-poly(lactic acid) (PEG114-block-PLAx) nanocarriers that were loaded with a ruthenium-based photosensitizer (PS). The action of tris(1,10-phenanthroline) ruthenium (II) bis(hexafluorophosphate) (RuPhen3) encapsulated in PEG114-block-PLAx micelles and vesicles was shown to result in an appreciable aPDT inactivation efficiency against planktonic Pseudomonas aeruginosa. In particular, the encapsulation of the PS, its release, and the efficiency of singlet oxygen (1O2) generation upon irradiation with blue light were studied spectroscopically. The antimicrobial effect was analyzed with two strains of Pseudomonas aeruginosa. Compared with PS-loaded micelles, formulations of the PS-loaded vesicles showed 10 times enhanced activity with a strong photodynamic inactivation effect of at least a 4.7 log reduction against both a Pseudomonas aeruginosa lab strain and a clinical isolate collected from the lung of a cystic fibrosis (CF) patient. This work lays the foundation for the targeted eradication of Pseudomonas aeruginosa using aPDT in various medical application areas.

Application of comparative sonochemical, photochemical, and sono-photochemical methods to obtain new silicon phthalocyanine with high singlet oxygen efficiency

Nowadays, non-invasive and nontoxic therapy methods are preferred to treat diverse types of cancer. Sono-photodynamic therapy (SPDT) is one of these alternative methods, combining the properties of PDT (photodynamic therapy) and SDT (sonodynamic therapy) and resulting in a higher singlet oxygen generation. The efficiency of this method is increased by synthesizing a complex with enhanced photochemical properties to use as a sensitizer. Phthalocyanines, especially with added derivatives holding diamagnetic metals such as Si4+, are often compounds used in PDT studies owing to their efficient yields of singlet oxygen formation. In this study, 4‑hydroxy-7-methoxyquinoline silicon phthalocyanine was synthesized and its anti-cancer therapy effect rates were calculated and compared by photochemical and sono-photochemical methods in DMSO. This research will help the studies that aim to obtain high singlet oxygen efficiency in therapeutic methods.

Obtaining new silicon phthalocyanines as sensitizers with high singlet oxygen efficiency using the combined effect of light and ultrasound

This study focused on the synthesis of innovative silicon phthalocyanines featuring halogen substituents and explored novel approaches to cancer therapy, focusing on photodynamic therapy (PDT), sonodynamic therapy (SDT), and sono-photodynamic therapy (SPDT), trying to achieve increased singlet oxygen generation. For this purpose, 2-Chloro-4-methylphenol and 2-Bromo-4-methylphenol silicon phthalocyanines were synthesized and their sonochemical, photochemical and sono-photochemical abilities were measured and compared. By employing various analytical methods, including spectroscopic techniques, the compounds' behavior and reactivity were thoroughly examined. With the recorded measurements resulting in significantly high quantum yields, this research sheds light on the potential utility of the achieved sensitizers in combatting cancer through novel therapeutic avenues.

Inverse Opal Photonic Hydrogels for Blue‐Edge Slow Photon‐Enhanced Photodynamic Antibacterial Therapy

AbstractPhotodynamic therapy is promising for combating bacteria by reactive oxygen species. However, the therapeutic efficiency of photodynamic antibacterial therapy (PDAT) is largely hindered by limited photon absorption and the low quantum yield of photosensitizers. Herein, a novel light‐harvesting platform is designed by decorating photosensitizer chlorine e6 (Ce6) into an inverse opal photonic hydrogel (Ce6/IOPG) framework for efficient light utilization to enhance PDAT. It is shown that the generating efficiency of singlet oxygen (1O2) can be tuned by the relative positions of the photonic bandgap (PBG) of IOPG and the absorption band of Ce6. The coupling of the slow photon effect with the efficient dispersion of Ce6 allows for a maximum generation of 1O2 of approximately 69.5‐fold and markedly enhances PDAT activity upon low light irradiation when the blue edge of PBG overlaps with the absorption band of Ce6. Particularly, slow photons at the blue edge show advantages in improving 1O2 generation compared to those at the red edge. The variation in 1O2 generation by altering the incident angle of light provides direct evidence for the slow photon effect in Ce6/IOPG. This work provides insights into blue‐edge slow photons in photodynamic enhancement and offers an advisable design principle for efficient antibacterial therapy.

A novel diaxially silicon phthalocyanine sensitizer for the generation of high efficiency singlet oxygen in photochemical and sono-photochemical studies

Cancer that is caused by unregulated proliferation and growth of cells in different organs and tissues throughout the body, is one of the most common, difficult to treat and deadly diseases of the century. While photodynamic therapy (PDT) method was primarily used in the treatment of cancer disease, sonodynamic therapy (SDT) method was then utilized as an alternative solution and finally sono-photodynamic therapy (SPDT) treatment was developed as the combination of these two therapeutic methods. Ultrasound waves have the ability to penetrate deep into tissues, allowing SDT and SPDT to reach and treat tumors located in deeper regions. The importance of these studies lies in their potential for non-invasive treatment, enhanced therapeutic efficacy, selective targeting, develop novel photosensitizers, deep tissue treatment, versatility in combination therapy, and their contribution to research and development in the field of therapeutic ultrasound and PDT. Today, the use of phthalocyanine complexes, known as sensitizers that can produce high amounts of reactive oxygen, is becoming increasingly important in these therapeutic methods. To achieve this objective, a novel silicon phthalocyanine derivative with bromo‑naphthoxy substitution was synthesized and subjected to characterization through various spectroscopic methods including elemental analysis, FT-IR, UV–Vis, MALDI-TOF MS, and 1HNMR. Photophysical, photochemical and sono-photochemical properties of the new complex were studied and analyzed. While the singlet oxygen efficiency in PDT method was found as ФΔ=0.78 in DMSO, ФΔ=0.69 in DMF, it was figured out in SPDT method as ФΔ=0.94 in DMSO and ФΔ=0.81 in DMF. This data shows that the new phthalocyanine compound is a good photosonosensitizer candidate that can be used in both PDT and SPDT methods.

Comparing Singlet Oxygen Generation of Schiff Base Substituted Novel Silicon Phthalocyanines by Sonophotochemical and Photochemical Applications.

Although the sonophotodynamic method has an effective therapeutic outcome for anticancer treatment compared with the photodynamic method, there are not enough related studies in the literature and this study aims to contribute to the development of sonophotodynamic studies. For this purpose, the Schiff base substituted silicon phthalocyanines were designed and synthesized as effective sensitizer candidates and the photophysicochemical and sonophotochemical features of the phthalocyanines were examined to increase singlet oxygen efficiency. The calculated ΦΔ values indicate that the contribution of substituent groups improved the production of singlet oxygen compared with silicon (IV) phthalocyanine dichloride (SiPcCI2 ) and also the sonophotochemical applications increased the singlet oxygen yields. The ΦΔ values (ΦΔ =0.76 for axially bis-{4-[(E)-(pyridin-3-ylimino)methyl]phenol} substituted silicon (IV) phthalocyanine (2a), 0.68 for axially bis-4-[(E)-{[(pyridin-3-yl)methyl]imino}methyl]phenol substituted silicon (IV) phthalocyanine (2b) in photochemical study) reached to ΦΔ =0.98 for 2a, 0.94 for 2b in sonophotochemical study. This article will enrich the literature on increasing singlet oxygen yield.

In Situ Embedding Hydrogen‐Bonded Organic Frameworks Nanocrystals in Electrospinning Nanofibers for Ultrastable Broad‐Spectrum Antibacterial Activity

AbstractIn the event of a public health crisis, highly effective and sustainable antimicrobial materials and equipment will be urgently needed. Here, the preparation is reported by electrospinning of broad‐spectrum antibacterial nanofibers embedded in a photoactive hydrogen‐bonded organic framework (HOF) of rod‐like nanocrystals ≈60 nm in length. The resulting HOF@PVDF‐HFP nanofibers maintain excellent tensile and breathability characteristics while shielding HOF nanocrystals against acid and alkali corrosion. A series of nanofibers embedded with different amounts and types of HOF nanocrystals are prepared to optimize their efficiency of singlet oxygen (1O2) generation. The 0.5 wt.% HOF‐101‐F@PVDF‐HFP nanofibers exhibit the most efficient 1O2 generation that is enhanced by a factor of almost 2 when compared with the HOF‐101‐F microcrystalline powder. The HOF@PVDF‐HFP nanofibers are demonstrated to highly effectively kill pathogens, including viruses, bacteria, and fungi in 30 min under ambient light conditions.

Rose bengal-decorated rice husk-derived silica nanoparticles enhanced singlet oxygen generation for antimicrobial photodynamic inactivation.

The online version contains supplementary material available at 10.1007/s10853-023-08194-z.

Fractional dependence of the free energy of activation on the driving force of charge transfer in the quenching of the excited states of substituted phenanthroline homoleptic ruthenium(ii) complexes in aqueous medium.

The photophysical characteristics of some homoleptic ruthenium(ii) phenanthroline derivatives are investigated in aqueous medium. The lifetimes of the excited 3MLCT state of the studied complexes were found to be very sensitive to the type of the substituents on the phenanthroline ligand and were found to increase from about 0.96 μs in case of the parent [Ru(Phen)3]2+ complex to 2.97 μs in case of [Ru(DPPhen)3]2+. The transient absorption spectra of the current set of complexes were studied also in aqueous medium. Quenching of the excited 3MLCT states of the studied complexes by molecular oxygen were studied and quenching rate constants were found to be in the range 1.02-4.83 × 109 M-1 s-1. Values of singlet oxygen quantum yields were found to be in the range 0.01 to 0.25, and the corresponding efficiencies of singlet oxygen thereby produced, f T Δ, were in the range 0.03-0.52. The mechanism by which the excited 3MLCT state is quenched by oxygen is discussed in light of the spin statistical factor rate constants and the competition between charge transfer and non-charge transfer quenching pathways. The partial charge transfer parameters, p CT, were obtained and found to be about 0.88 for all complexes except for complexes with f T Δ values lower than 0.25. The correlation of the activation free energies ΔG ≠ of the exciplexes formation with the driving force for charge transfer, ΔG CET, gives a charge transfer character of the exciplexes of about 35.0%.

Synthesis of axially Schiff base new substituted silicon phthalocyanines and investigation of photochemical and sono-photochemical properties

Sono-photodynamic therapy, which show a very high therapeutic effect compared to photodynamic therapy, is a newer method for anticancer treatments. However, unlike Photodynamic therapy (PDT), the number of studies measuring the efficiency of singlet oxygen for the Sono-photodynamic therapy (SPDT) method is quite insufficient in the literature. Therefore, this study aimed to synthesis novel axially substituted silicon (IV) phthalocyanines containing imine groups with improved photochemical properties and then reported the efficiency of singlet oxygen by both of photochemical and sono-photochemical studies. According to the results, the substituent group increased the singlet oxygen yield of silicon (IV) phthalocyanine dichloride and the sono-photochemical effect increased the singlet oxygen yields (ΦΔ=0.35 for 2a, 0.69 for 2b in photochemical study, 0.78 for 2a, 0.97 for 2b in sono-photochemical study).This article may pave the way to achieve high singlet oxygen efficiency.

Polymer-coated calcium peroxide nanoparticles as an oxygen self-supplying platform for enhanced photodynamic therapy

Photodynamic therapy, employing photosensitizer catalysis to convert oxygen into cytotoxic reactive species upon light irradiation, holds high promise in tumor therapy due to its high selectivity and non-invasiveness. However, the anticancer efficacy is greatly limited by the hypoxia microenvironment of tumor tissue. Herein, we report an oxygen self-supplying nano-platform for photodynamic therapy, which is fabricated by calcium peroxide nanoparticles with surface modification of a copolymer, PMPS-b-P(NIPAAm-co-VBRB) by silanization. In this system, calcium peroxide nanoparticle acts as an oxygen donor while PMPS-b-P(NIPAAm-co-VBRB) plays the role of photosensitizer and can stabilize shell of calcium peroxide nanoparticles. The resultant polymer-coated nanoparticles have a uniform size of 228 nm measured by dynamic light scattering. The polymer-coated calcium peroxide nanoparticles show greater production efficiency of singlet oxygen to deplete 1,3-diphenylisobenzofuran than PMPS-b-P(NIPAAm-co-VBRB) upon the exposure to the LED@520 nm. The result demonstrates that the polymer-coated calcium peroxide nanoparticles are effective for oxygen generation and hold potential to enhance the efficacy of photodynamic therapy.