METHODS

• Excised human abdominal skin samples of 500-µm thickness were pretreated with a 1440-nm 
laser with 80 microscopic treatment zones (MTZ)/cm2 (1.2 W), 1440-nm laser with 320 MTZ/cm2 
(3 W), 1927-nm laser with 320 MTZ/cm2 (1 W), or received no pretreatment (Table 1)

Table 1. Experimental Parameters

• Following laser pretreatment, 10% ascorbic acid (Obagi®, Long Beach, CA; 2010 formulation) 
was applied, and permeation was measured up to 24 hours after application (Figure 1)

• Samples were filtered and analyzed using high-performance liquid chromatography to measure 
topical permeation and retention for laser-treated samples and untreated controls

• Total uptake was calculated as the sum of the normalized cumulative permeation and 
retention in each sample

• Average total uptake was compared between laser-treated samples and untreated controls to 
determine the uptake enhancement ratio

Figure 1. Study design for testing uptake of topicals on skin tissue. 

PBS, phosphate-buffered saline.

RESULTS
Permeation

• Pretreatment with the 1927-nm laser with 320 MTZ/cm2 enhanced permeation of 10% ascorbic 
acid at 24 hours posttreatment relative to other pretreatments and untreated control (Figure 2)

Figure 2. Cumulative permeation of 10% ascorbic acid after laser pretreatment. 

Values are mean ± standard deviation. MTZ, microscopic treatment zones.

Uptake

• Pretreatment with the 1927-nm laser with 320 MTZ/cm2 enhanced uptake by >4 times 
compared to the 1440-nm laser with 320 MTZ/cm2 (7.8 vs 1.8 mg/cm2; Table 2) 

 – Compared to the 1440-nm laser with 80 MTZ/cm2 (0.5 mg/cm2), uptake was enhanced by >15 times
 – Compared to untreated control (0.2 mg/cm2), uptake was enhanced by >33 times

• Pretreatment with the 1440-nm laser with 320 MTZ/cm2 was associated with 
 – >3-times greater uptake compared to the 1440-nm laser with 80 MTZ/cm2 (1.8 vs 0.5 mg/cm2)
 – >7-times greater uptake compared to untreated control (1.8 vs 0.2 mg/cm2)

Table 2. Uptake Ratios of 10% Ascorbic Acid

SYNOPSIS

• The stratum corneum forms a vital protective barrier along the outer layer of the skin, but also prevents optimal uptake of topical formulations1

• Lasers can facilitate better penetration and absorption of topicals by disrupting the stratum corneum and tight junctions in the epidermis2

• Non-ablative lasers generally target dermal tissue and largely spare the stratum corneum, which minimizes overall thermal side effects and postprocedural recovery time, while fractionation further 
reduces postprocedural downtime3,4

• The relationship between topical uptake and laser device settings, such as wavelength, peak power, and spot density, must be quantified to optimize treatment benefits

Enhanced Uptake of 
10% Ascorbic Acid After 
1440-nm or 1927-nm 
Non-ablative Fractional 
Diode Laser Treatment

Jordan V. Wang, MD, MBE, MBA1; Paul M. Friedman, MD1,2;  Adarsh Konda, PharmD3; Catherine Parker, NP, MSN4; Roy G. Geronemus, MD1
1Laser & Skin Surgery Center of New York, New York, NY; 2Dermatology and Laser Surgery Center, Houston, TX; 3Bausch Health US, LLC, Bridgewater, NJ; 4Solta Medical, Bothell, WA 

OBJECTIVE
• To quantify uptake of 10% ascorbic acid 

following pretreatment with low-power  
1440-nm or 1927-nm non-ablative fractional 
diode lasers (Clear + Brilliant® laser system; 
Solta Medical, Bothell, WA) with varying 
treatment densities

CONCLUSIONS
• In this ex vivo analysis, the greatest 

enhancement of 10% ascorbic acid uptake  
was seen with 1927-nm pretreatment at  
320 MTZ/cm2 and 1.0 W, compared to  
1440-nm wavelengths at varying wattage  
and treatment densities

• This provides a foundation for clinical studies 
on laser-enhanced uptake of ascorbic acid and 
other topicals, which can allow clinicians to 
better understand the relationship between 
quantifiable uptake enhancement and patient-
centered outcomes

Presented at the 2021 Fall Clinical Dermatology Conference • October 21-24, 2021 • Las Vegas, NV, and Virtual

Funding information: This study was sponsored by Solta Medical. Medical writing support was provided by MedThink 
SciCom and funded by Solta Medical. 

Disclosures: JVW is an investigator for Solta Medical. PMF serves on the advisory board and speaker bureau for Solta Medical.  
AK and CP are employees of and may hold stock or stock options in Solta Medical. RGG is an investigator and advisory board 
member for Solta Medical.

References: 1. Lee et al. Eur J Pharm Sci. 2016;92:1-10. 2. Machado et al. Aesthetic Plast Surg. 2021;45:1020-1032. 3. Friedman et 
al. J Drugs Dermatol. 2020;19:s3-s11. 4. Farkas et al. Aesthet Surg J. 2013;33:1059-1064.

Figure 1

Sample & refill

500-µm skin graft

Topical formulation

PBS solution w/ 0.2% sodium azide

Donor chamber

Permeation/Diffusion chamber
Stir bar

Stir rotation

Parameter Setting
Device wavelength, nm 1440 1440 1927
Spot density, MTZ/cm2 80 320 320
Peak power, W 1.2 3 1
Spot size, µm 130 130 130
Pulse energy, mJ 9 9 9
MTZ, microscopic treatment zones.

1440 nm (80 MTZ/cm2) 1440 nm (320 MTZ/cm2) 1927 nm (320 MTZ/cm2)
Control 2.18 ± 0.55 x 7.75 ± 2.02 x 33.61 ± 0.02 x
1440 nm (80 MTZ/cm2) — 3.56 ± 0.70 x 15.45 ± 0.02 x
1440 nm (320 MTZ/cm2) — — 4.34 ± 0.07 x
Values are mean ± root mean square. MTZ, microscopic treatment zones.

-1

1

3

5

7

9

0 5 10 15 20 25 30

C
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 m
g/

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Time, hours

Control
KOVAR-1435nm
TUSCANY-1435nm
TUSCANY-1927nm

Control
1440 nm (80 MTZ/cm2)
1440 nm (320 MTZ/cm2)
1927 nm (320 MTZ/cm2)

7.44

1.47
0.40
0.14