Exhibit 10.6


 


October 9, 2020


 


Applied DNA Sciences, Inc. (the “Company”)


Attn: Chief Financial Officer


50 Health Sciences Drive


Stony Brook, New York 11790


 


Re:         Securities Purchase Agreement,
dated July 16, 2019, between the Company and Dillon Hill Capital, LLC (the “Holder”) and Secured Convertible Note,
dated as of July 16, 2019 by the Company, in favor of Holder.


 


Dear Beth Jantzen,


 


Reference is made to (i) Securities
Purchase Agreement, dated July 16, 2019, between the Company, Holder and certain other Buyers (as defined in the Purchase
Agreement) (as amended, restated, supplemented or otherwise modified from time to time and in effect on the date hereof the “Purchase
Agreement”), (ii) Secured Convertible Note, dated as of July 16, 2019, by the Company in favor of the Holder (as
amended, restated, supplemented or otherwise modified from time to time and in effect on the date hereof, the “Note”),
(iii) Security Agreement, dated as of October 19, 2018, by the Company in favor of Delaware Trust Company (the “Collateral
Agent”) (the “Company Security Agreement”), (iv) Guaranty and Security Agreement dated as of October 19,
2018, by APDN (B.V.I) Inc. (the “Guarantor”) in favor of the Collateral Agent (as amended, restated, supplemented or
otherwise modified from time to time and in effect on the date hereof, the “Guarantor Security Agreement”), (v) Intellectual
Property Security Agreement, dated October 19, 2018, by the Company in favor of the Collateral Agent (“Company IP Security
Agreement”) and (vi) Intellectual Property Security Agreement dated as of October 19, 2018, by the Guarantor in
favor of the Collateral Agent (as amended, restated, supplemented or otherwise modified from time to time and in effect on the
date hereof, the “Guarantor IP Security Agreement”). Capitalized terms used but not otherwise defined herein shall
have the meanings given them in the Securities Purchase Agreement.


 


The Company has informed the Holder that
the Company intends to repay the Note and the obligations thereunder (the “Obligations”). The amount due and payable
under the Note on October 9, 2020 (the “Target Date”) which includes principal and accrued but unpaid interest
(the “Payoff Amount”) is $1,665,581.


 


Wire instructions:          [Intentionally
omitted.]


 


Holder and Collateral Agent agree that
upon Holder’s receipt of the full referenced amount above, (i) all of the obligations and liabilities of the Company
and the Guarantor under the Note, the Purchase Agreement, any security agreement, any guaranty agreement (including without limitation
the Company Security Agreement, the Guarantor Security Agreement, the Company IP Security Agreement, and the Guarantor IP Security
Agreement) and any other documents and instruments related thereto (“Documents”) will be automatically satisfied in
full, (ii) the Note and other Documents will be automatically terminated and of no further force or effect (other than any
provisions or terms of the Documents (including inchoate indemnity obligations) that are specified in any such agreement as surviving
that respective agreement’s termination, which shall continue to survive notwithstanding the foregoing), (iii) all liens,
mortgages and other security interests in or on the Company, the Guarantor, or any of the Company’s or Guarantor’s
assets or properties shall be automatically released and be of no further force or effect with no further action on our part, (iv) Collateral
Agent authorizes the Company and its respective agents and assignees to file termination statements of all UCC financing statements
and/or mortgages filed by the Collateral Agent covering the assets of the Company or Guarantor securing the Obligations, and (v) Collateral
Agent shall promptly return all original collateral in its possession to the Company or the Company’s designee. Upon the
Company’s request from time to time, Collateral Agent and Holder shall promptly execute and deliver such additional lien
and/or mortgage releases as may be necessary or requested to effectively terminate or evidence the termination of any and all of
Collateral Agent’s liens, mortgages and other security interests on any of the assets and properties of the Company.


 






    


     


    

 


This
letter agreement shall be governed by the laws of the State of New York.


 


This letter agreement may be executed in
any number of and by different parties hereto on separate counterparts, all of which, when so executed, shall be deemed an original,
but all such counterparts shall constitute one and the same agreement. Any signature executed and delivered by a party by facsimile
or electronic transmission (including email transmission of a PDF image or an electronic signature complying with the U.S. federal
ESIGN Act of 2000, e.g., docusign.com) shall be deemed to be an original signature hereto.


 


	 	Sincerely,
	 
	 	By:	/s/ Bruce Grossman
	 	Name:	 Bruce Grossman
	 	Title:	Chief Executive Officer
	 	 	Dillon Hill Capital, LLC 

200 Business Park Drive
    

Suite 306 
	 	 	Armonk, NY 10504
	 	
	 	By:	 /s/ Benjamin Hancock
	 	Name:	 Benjamin Hancock
	 	Title:	 Assistant Vice President
	 	 	Delaware Trust Company 

251 Little Falls Dr.

 Wilmington, DE 19808