Table 3 A comprehensive overview of the advantages and disadvantages of strategies aimed at overcoming light penetration challenges in deep tumor phototherapy

Spontaneous luminescent nanomaterials

Chemiluminescent NP

Not required

1). Not limited by external excitation sources.

2). Can induce a more prolonged therapeutic process.

1). Weak luminescence intensity, resulting in generally lower PDT efficiency upon excitation.

2). Inability to adjust the power and duration of the light source.

3). Potential damage to normal tissues.

4). Chemical luminescent materials such as luminol may cause damage to biological components like DNA.

Bioluminescent NP

Not required

Cerenkov luminescence-excited PDT

Not required

NIR light-excited phototherapy

Upconversion NP

NIR light

1). NIR has good tissue penetration depth.

2). High chemical stability.

3). Tunable surface chemistries.

1). The penetration limit of NIR does not exceed 1 cm.

2). UCNPs have relatively low quantum yields.

3). NIR irradiation may cause thermal damage.

4). UCNPs are typically non-degradable.

5). The FRET efficiency between UCNPs and PS needs to be further improved.

Non-photo-induced dynamic therapy

RDT

x-ray

1). X-rays have good tissue penetration capability.

2). Combining radiotherapy and PDT can further enhance the treatment efficacy.

1). Low light conversion efficiency and low ROS generation.

2). Repeated X-ray exposure can cause severe radiation damage to normal tissues.

3). Requires special materials.

4). Scintillators have potential cytotoxicity.

SDT

Ultrasound

1). Ultrasound has deep tissue penetration (>10 cm).

2). Ultrasound is widely used in clinical settings.

1). Ultrasound parameters are closely related to treatment efficacy, but there is currently no unified standard for ultrasound parameters.

2). The toxicity and biocompatibility of sonosensitizers require further extensive research and confirmation.

MDT

Microwave

Microwaves have stronger penetration capability.

1). Microwave energy is too low to effectively induce ROS production.

2). Research is still in its early stages and requires further study to confirm its effectiveness.

Wireless PDT

Light

1). Facilitating thorough excitation of photosensitizers in deep tissues.

2). Controllable wavelength and dosage of the excitation source.

1). Surgical procedures are required for implantation and removal, which may cause side effects.

2). Long-term biocompatibility needs further validation after implantation.

3). Implantation may induce thermal effects on surrounding normal tissues.

4). Adverse immune reactions in the body may occur.