Biomedical applications and prospects of temperature‐orchestrated photothermal therapy

Abstract

Photothermal therapy (PTT) has been regarded as a promising strategy considering its advantages of high inherent specificity and a lower invasive burden. Since the photothermal killing of cells/bacteria showed different patterns of death depending on the varying temperature in PTT, the temperature change of PTT is vital to cell/tissue response in scientific research and clinical application. On one hand, mild PTT has received substantial attention in the treatment of cancer and soft/hard tissue repair. On the other hand, the high temperature induced by PTT is capable of antibacterial capacity, which is better than conventional antibiotic therapy with drug resistance. Herein, we summarize the recent developments in the application of temperature-dependent photothermal biomaterials, mainly covering the temperature ranges of 40-42°C, 43-50°C, and over 50°C. We highlight the biological mechanism of PTT and the latest progress in the treatment of different diseases. Finally, we conclude by discussing the challenges and perspectives of biomaterials in addressing temperatureorchestrated PTT. Given a deep understanding of the interaction between temperature and biology, rationally designed biomaterials with sophisticated photothermal responsiveness will benefit the outcomes of personalized PTT toward various diseases.

Photo‐Controllable Smart Hydrogels for Biomedical Application: A Review

“…[221] PTT is a therapeutic strategy that converts light energy into heat energy to ablate tumors, and temperatures are most commonly used between 43 and 50 °C, because the permeability of blood vessels and cell membranes will be significantly increased at lower temperatures in this range, and rapid irreversible cell damage will occur at higher temperatures. [222][223][224][225] Traditional PTT intravenous PTA, on the other hand, has limited biocompatibility and non-targeted accumulation, which might result in unanticipated adverse effects on healthy tissues and organs. Additionally, because PTAs may not effectively accumulate at the site of the lesion, cancer cells might not be entirely removed, which could result in tumor recurrence.…”

“…[ 102,103 ] It is frequently used in tumor therapy because a moderate local temperature increase (45–50 °C) can increase blood vessel and cell membrane permeability and cause rapid irreversible cell damage through exogenous or endogenous mitochondrial apoptosis pathway death at higher temperatures in this range. [ 27,104,105 ] Bacteria can be destroyed by protein denaturation, cell membrane damage, DNA breakage, and other mechanisms when the local temperature surpasses 53 °C, which is beneficial for the healing of infected wounds and can effectively prevent bacterial growth. [ 106–108 ]…”

Self-healing hydrogels for bone defect repair

“… 205 Thus, the combination of PTT with chemotherapy, photodynamic therapy, or immunotherapy may improve efficacy and reduce side effects. 206 Matheny performed a prospective, randomized, controlled, blinded clinical trial to evaluate the safety and efficacy of a novel self-crosslinked HA hydrogel. This hydrogel was compared with carboxymethylcellulose viscous foam in terms of promoting healing after ethmoidectomy.…”

Biocompatible Polymer‐Modified Nanoplatform for Ferroptosis‐Enhanced Combination Cancer Therapy

“…To achieve effective tumor ablation, a high temperature of above 50 °C is usually required for PTT monotherapy. [57] Liu et al explored a nanomotors (PHPF NMs) with hemin and-Fc -depositing on the surface of bowlshaped polydopamine (PDA) for PTT and FT. [58] Owing to the superior photothermal conversion capacity of PDA, PHPF NMs could rapidly elevate the tumor temperature by ≈20 °C within 10 min of 808 nm laser irradiation (1.6 W cm −2 ). The photothermia could accelerate the release of hemin and -Fc from PHPF NMs, which further reacted with endogenous H 2 O 2 to increase •OH generation and consumed GSH for the FT-PTT.…”