A method to obtain the thermal parameters and the photothermal transduction efficiency in an optical hyperthermia device based on laser irradiation of gold nanoparticles

Abstract

Optical hyperthermia systems based on the laser irradiation of gold nanorods seem to be a promising tool in the development of therapies against cancer. After a proof of concept in which the authors demonstrated the efficiency of this kind of systems, a modeling process based on an equivalent thermal-electric circuit has been carried out to determine the thermal parameters of the system and an energy balance obtained from the time-dependent heating and cooling temperature curves of the irradiated samples in order to obtain the photothermal transduction efficiency. By knowing this parameter, it is possible to increase the effectiveness of the treatments, thanks to the possibility of predicting the response of the device depending on the working configuration. As an example, the thermal behavior of two different kinds of nanoparticles is compared. The results show that, under identical conditions, the use of PEGylated gold nanorods allows for a more efficient heating compared with bare nanorods, and therefore, it results in a more effective therapy.

Insight into the Effect of Stabilizers on Anticancer and Antibacterial Activity of AgBiS2 Nanomaterial

“…It is worth mentioning that few crystalline nanoparticles reported in the literature exhibited a good PTT effect [1,5] . These results also demonstrate the importance of HMDS‐assisted method to obtain surfactant‐free nanoparticles to acquire a more active photothermal agent [5,46–51] …”

“…The excited PTT agent undergoes vibrational relaxation through non‐radiative decay, releasing the energy as heat, which is transferred to the cancer cells. The cells die when the temperature of the tissue is increased above 46 °C due to protein denaturation and plasma membrane destruction [5,46–51] . The photothermal effect of sf‐AgBiS 2 and PEG‐AgBiS 2 (20 μg/ml each) was measured at various time using an 808 nm NIR laser (power=650 mW) for 3–10 min (Figure 5).…”

“…The cells die when the temperature of the tissue is increased above 46 °C due to protein denaturation and plasma membrane destruction. [5,[46][47][48][49][50][51] The photothermal effect of sf-AgBiS 2 and PEG-AgBiS 2 (20 μg/ml each) was measured at various time using an 808 nm NIR laser (power = 650 mW) for 3-10 min (Figure 5). It was found that the temperature of sf-AgBiS 2 reached to a maximum 53.3 °C after 10 min of radiation and 43.9 °C with 3 min exposure was.…”

High-quality manufacturing method of complicated castings based on multi-material hybrid moulding process

“…The measured densities of the fi ve moulding sands are shown in Table 2. Specific heat capacity and thermal conductivity of the moulding sands were measured using a transient method (laser method) [7][8][9] . Interfacial heat transfer coeffi cient of the moulding sands has been measured using heat conduction temperature measurement method [10] .…”

Перспективы Применения Наночастиц Золота, Серебра И Оксида Железа Для Повышения Эффективности Химиотерапии Опухолевых Новообразований

“…Èäåÿ íàãðåâà çîëîòûõ íàíî÷àñòèö ëàçåðíûì èçëó-÷åíèåì ÈÊ-äèàïàçîíà ñ öåëüþ ëîêàëüíîãî òåðìè÷åñêîãî ïîâðåaeäåíèÿ êëåòîê áûëà ïðåäëîaeåíà â 2003 ã. Ê. Ïèòñèëëèäèñîì [108].  ïîñëåäóþùåì áûëà ïîêàçàíà âîçìîaeíîñòü ïðèìåíÿòü ìåòîä äëÿ ëîêàëüíîãî ðàçðóøåíèÿ îïóõîëåâûõ êëåòîê [109]. Îäíàêî âñå ýêñïåðèìåíòàëüíûå èññëåäîâàíèÿ ïî ïðèìåíåíèþ ãèïåðòåðìèè íàíî÷àñòèö çîëîòà îñóùåñòâëÿþòñÿ in vitro, òàê êàê äëÿ íàãðåâà íàíî÷àñòèö çîëîòà íà äëèíå âîëíû ïëàçìîííîãî ðåçîíàíñà èõ íåîáõîäèìî îáëó÷àòü ëàçåðíûì èçëó÷åíèåì ñ äëèíîé âîëíû îêîëî 520 íì, à èçëó÷åíèå ñ òàêîé äëèíîé âîëíû ïðàêòè÷åñêè íå ïðîõîäèò â áèîëîãè÷åñêóþ òêàíü.…”