Microneedles vs. Other Transdermal Technologies
Boris Stoeber, Raja K Sivamani, Howard I. Maibach in Microneedling in Clinical Practice, 2020
While volumes of up to 250 µL have been delivered (75), these result in more damage to surrounding and deeper skin tissues. Volumes in the nanoliter range minimize damage and splashback (76). Jang and colleagues used an ER:YAG laser to induce a microjet for controlled delivery of epidermal growth factor and human growth hormone (77, 78). A 250-µs laser pulse generated vapour bubbles and downstream shockwaves that propelled the API solution through a nozzle forming a microjet that penetrated the skin. The device was designed with two compartments to prevent any detrimental thermal effects to the API, and to separate the laser-ablation process from the skin. The microjet velocities between 23.0 ± 4.0 and 50.6 ± 1.6 m/s delivered a maximum of 2100 ± 28 nL and minimum of 358 ± 14 nL (an approximately 5.8-fold increase). Delivery of epidermal growth factor and human growth hormone in porcine skin was achieved, as determined by gene expression of keratinocyte laminin and fibroblast elastin respectively. There was no significant difference in gene expression for laser energies of 408 and 816 mJ and two different drug concentrations of 10 and 100 ng/mL suggesting the laser energy caused minimal thermal damage to the API. Continued development of liquid jet injector systems may continue to offer improvements in delivery control with minimal tissue damage, but will need to be achieved at low cost and complexity.
Blocks of Nerves of the Trunk
Bernard J. Dalens, Jean-Pierre Monnet, Yves Harmand in Pediatric Regional Anesthesia, 2019
Parasternal and posterior approaches are more prone to lead to pneumothoraces. The occurrence of this complication depends upon the site of puncture. It also depends upon the experience of the anesthesiologist. In a series of 10,941 (adult) patients, Moore1 reported a frequency of only 0.07% clinically significant pneumothoraces. The use of a jet injector has been recommended for preventing this complication, but the procedure has not been evaluated in children.29,30
Injection therapy for nail disorders
Archana Singal, Shekhar Neema, Piyush Kumar in Nail Disorders, 2019
A needle-free jet injector, such as derm-o-jet or port-o-jet, can also be used. There is less injection pain, but it is not recommended owing to the difficulty in sterilizing the apparatus. Also, there is theoretical possibility of transferring infection from one patient to the next with the gun due to splash-back of blood on to the instrument and the physician.7
Advances in subcutaneous injections: PRECISE II: a study of safety and subject preference for an innovative needle-free injection system
Published in Drug Delivery, 2021
E. Lynne Kelley, Richard H. Smith, Gillian Corcoran, Sandra Nygren, Mary V. Jacoski, Andrea Fernandes
Autoinjectors simplify at-home self-injection of medications, but although hidden, they still contain a needle. Additionally, autoinjectors require the user to press and hold the device against the skin for up to 15 seconds, and larger volumes can require up to 30 seconds (Schneider et al. 2020). Over the past several years, technologies that use needle-free injection methods have been developed to address the challenges associated with injection pain and needle anxiety. A spring-loaded reusable jet-injector has demonstrated positive data for vaccine delivery, although use has been limited to trained healthcare professionals (de Menezes Martins et al. 2015; Basu et al. 2021). Among the newest devices is the Portal PRIME needle-free jet injection system (Portal Instruments, Inc., Cambridge, MA). Where previousneedle-free injection systems relied on mechanical spring-based or gas-based approaches to achieve the high pressure required to eject at a velocity necessary to pierce the skin, the lack of real-time control limited their application for medications that require larger volumes and those with higher viscosity (Taberner et al. 2012). The Portal PRIME needle-free injector delivers a narrow stream of medication through the skin in less than half a second using technology that controls and modifies the fluid velocity in real time by employing a feedback control loop connected to an electro-mechanical actuator that generates the force needed to inject the fluid.
Poxvirus-based vector systems and the potential for multi-valent and multi-pathogen vaccines
Published in Expert Review of Vaccines, 2018
Natalie A. Prow, Rocio Jimenez Martinez, John D. Hayball, Paul M. Howley, Andreas Suhrbier
Avoiding needles has a series of inherent advantages [99,100] and a number of needle-free vaccination strategies are being developed (Table 5). Smallpox vaccines were usually given using a process of scarification, which involves using a bifurcated needle (which holds a droplet of the vaccinia vaccine) pressed several times into the skin (deep enough to evoke a trace of blood after 15–30 s) [101]. A multi-dose jet injector (‘Press-o-Jet’) was also developed in 1955 for needle-free delivery of smallpox vaccines [102]. rMVA vaccines are usually given via a needle using the intramuscular route (or the subcutaneous route), although the percutaneous route has also worked in preclinical studies [103]. Vet Jet™ delivery of Purevax® represents the first licensed needle-free delivery of a recombinant poxvirus vaccine, with Stratis jet injection of MVA in phase 2 human clinical trials. Other technologies include needle-free intradermal delivery of solid dissolvable vaccine formulations (ImplaVax™) (Table 5). Clearly of considerable value would be systems that provide both lyophilization, solidification, or dry coating technologies that reduce cold chain requirements combined with needle-free delivery. Progress in this field may also open new avenues for multi-vaccine co-delivery, with ‘dry vaccines’ potentially overcoming some of the hurdles associated with simple mixing of multiple liquid vaccines.
Needle-free jet injection of insulin glargine improves glycemic control in patients with type 2 diabetes mellitus: a study based on the flash glucose monitoring system
Published in Expert Opinion on Drug Delivery, 2021
Xiaocen Kong, Menghui Luo, Ling Cai, Peng Zhang, Rengna Yan, Yun Hu, Huiqin Li, Jianhua Ma
The results of the survey feedback indicated that most patients preferred the conventional insulin pen over the jet injector. However, the jet injector and insulin pen showed similar levels of patient convenience for operation, satisfaction, acceptance and injection pain scores. The patient preference might be related to the short period over which the jet injector was used. In addition, the patients in this study generally tolerated insulin pen injections without obvious discomfort, consequently feeling no need to change the mode of injection. Future studies are necessary to reveal the tolerability of the jet injector after personal experience in daily clinical practice for sufficient duration.
Related Knowledge Centers
- Chorionic Gonadotropin
- Diabetes
- Epidermis
- Hepatitis B
- Vaccination
- Insulin
- Injection
- Syringe
- Intradermal Injection
- Time-Lapse Microscopy